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Gear / Technical Help => Recording Gear => Topic started by: justme on November 02, 2021, 11:16:53 PM
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Rode is realising an interesting universal USB interface based on the iOS only SC-6L.
The AI-micro is I’ll be usable for pretty much anything with USB.
https://rode.com/interfaces-and-mixers/ai-micro
Specs: https://edge.rode.com/pdf/page/1871/modules/4638/AI-Micro_datasheet.pdf
https://rode.com/blog/all/introducing-the-ai-micro-ultra-compact-dual-channel-interface
Key Features of the AI-Micro
- Ultra-compact dual-channel interface for recording high-quality audio on computers and mobile devices
- Compatible with virtually any microphone with a 3.5mm output, including RØDE VideoMics, lavaliers, wireless systems, and stereo microphones
- Auto-sensing inputs for connecting TRS or TRRS microphones
- High-power headphone output for crystal-clear, zero-latency audio monitoring and playback
- Connects seamlessly to computers, smartphones and tablets via its universal USB output (USB-A, USB-C and Lightning cables supplied)
- Compatible with the entire RØDE app suite for expanded features and functionality, on-the-go configuration, and broadcast-quality recording on any device
- Designed and made in RØDE’s state-of-the-art facilities in Sydney, Australia
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$70 bucks for this. I'll grab one once they're available. Game changer if it works as described.
"The device features two 3.5mm inputs for independently recording via a pair of microphones, and one of these inputs can automatically detect when a single stereo microphone is used instead." From techradar
https://www.techradar.com/news/rodes-new-ai-micro-turns-your-phone-into-a-portable-audio-recording-studio
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I wonder what the plug-in power voltage is? I couldn't find that anywhere.
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Probably 3v or so. I would assume that you'll need a battery box.
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Tiny, inexpensive, made by a reputable company...
We have come a long way in the less than 20 years I've been recording.
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https://www.youtube.com/watch?v=9_jt8PRrzOs&ab_channel=R%C3%98DEMicrophones
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Very interesting. What phone app would you use to adjust and monitor record levels?
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Very interesting. What phone app would you use to adjust and monitor record levels?
This would certainly work https://www.rode.com/software/reporter_app but I'm curious as well about compatibility with other apps especially Android.
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100dB of dynamic range, versus e.g. 142dB on a MixPre. My guess is that this was intended for dialogue/interviews/Zoom, where I expect a tiny interface would be a nice upgrade over stock laptop/phone hardware, but classical music at least would benefit from more dynamic range.
Also, it maxes out at 48kHz---again, great for dialogue/Zoom/interviews (and obviously great if you have the very best top shelf equipment) but most of us want more on a cheap interface for music.
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I've just ordered this to go with my shiny new highly expensive DJI Action 2 video camera. Unlike most such small cameras, this one doesn't use a proprietary interface for getting audio into its USB C port, but anything that works with Android or PC will do. I've used it with a audio technica ATR2x-USB interface, and it also works with the Zoom F1 and H1N and no doubt the rest. The camera itself has remarkable built in mics - 4 of them - which provide almost a binaural immersive sound. It's like a Zoom H2N in a way, except it does excellent video as well. I think the Rode interface will be somewhat larger than the camera...
I'll report on how this goes in due course. Mics will be Roland binaural or Sennheiser stereo shotgun.
Thanks to the OP for the heads-up!
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I just pre-ordered one from Sweetwater. Let us know how it goes for you, Ozpeter. B&H says availability is the end of December.
If this works out, I'll have an ultra low profile setup. MKE2 (from the gopro deal, permanently mounted in hat) > homemade "ugly" battery box > Rode AI-Micro > phone
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I ordered from a company about 25 minutes away, express delivery. They sent it from a warehouse in another state, parcel post, delivery might take until the end of next week! Grrr. Meanwhile I checked a local high-end video equipment sales company ten minutes away and they have it in stock... so I'm due to collect one from there this afternoon, and I hope to get a video online very soon. It will mainly be concerned with interfacing with the DJI Action 2 but of course I'll also do a quick test with Android and iPhone devices too.
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Bad news... Rode have stuffed this up. It's a fantastic device except - when you connect a stereo mic and configure it appropriately in the app, it only works on the left channel, unless it is a self powered mic. In other words, the plug in power is only supplied to one capsule. Doh. So it won't work with my Roland binaural mics, for instance, which was probably my prime reason for purchase. I have yet to check it with a voltmeter, but I'm 99% sure that's what they have done. I had a long talk on the phone with a Rode tech person and he was puzzled, so they may not realise what they have done because... Rode don't sell stereo mics needing PiP as far as I know. But let's face it, every portable recorder on the planet supports such stereo mics, so really they can't say people don't need it.
At least it does work with my DJI Action 2 camera...
[Edit - plug in power does appear on both sides, so now I'm puzzled as to why it won't work with stereo mics. I think it was 2.8 volts. Same voltage shows when using mono mics on the mono configured inputs.]
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Apologies if I misread your post - Have you tested it with stereo microphones using external power (like a battery box)?
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I've tested it with a Sennheiser stereo shotgun which has its own battery, and it's fine with that.
https://youtu.be/gZPbYP3TYK4
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Briefly, if you connect a PiP stereo mic to a 3.5mm > 3.5mm female>female adapter and then to a Rode SC11 splitter lead to channels 1 & 2 - so it thinks it's got two mono mics connected for stereo input - it works. I'[m hoping the Rode will fix this with a FW update...
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Peter, have you tested the Reporter app much? I'm wondering if there is a time limit.
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No, sorry, I've mainly been using it for video with the Action 2 camera.
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My unit was shipped yesterday. Hopefully I will be able to test it soon.
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The unit just arrived and upon plugging it in, it automatically connected to the Rode app I had preinstalled. I used the output of my baby nbox into input 1 and it was recognized as a stereo input once I selected it on the app.
The app has 24 db of gain and records at either 24 bit 48khz or compressed 48khz 128, 256, or 320kbps mp3. Optional high pass filters are at 75 and 150 hz.
I will test it soon as a backup rig but the test file I made earlier pulled up as a stereo file in Audacity. My only worry right now is with phone battery life - I may get a cheap android just for recording in the near future. Also, I don't like that you have to export your recordings to the cloud. I need to find where in the file system it is saving them so I can export manually.
https://imgur.com/a/WSoP6YG
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I have tested the device and it works well as long as you keep the screen up. However, on my S9+, once I tap the power button to turn off the screen, the levels drop dramatically and seconds later completely shut off. I do not want to keep the screen on while the device is in my pocket and there is no lock option to use while doing so.
I sent in a service request to Rode but this does not bode well for the device.
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I will try to test mine in this respect. Have you tried different recording apps?
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I will try to test mine in this respect. Have you tried different recording apps?
I have tried pretty much all of them on Google Play. The only one that works correctly with the stereo mode is Rode Reporter. Even the Shure Motiv app will not recognize the stereo pair.
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As memory serves me, one of my two phones won't record in stereo from USB-C, the other will. I really must retest to remind myself.
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Coming back to this...I just got a new iphone so I thought I would try it out before I absolutely hit the return deadline.
This thing works like a charm with Apogee Metarecorder, recognizing the stereo input and all. All of the problems I was having before are nonexistent now. I tested it with my Videomic Stereo and with a 3.5mm out from my Mixpre 6 and it recognized stereo on both with no dropouts or volume adjustments when the phone went to sleep.
I have a show coming up on Saturday that I will try and get some samples at.
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I'm glad you finally got a good result!
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I'm glad you finally got a good result!
Thank you. I think Android is too finicky for them to bother perfecting...
Bias on these is 2.8v on both channels.
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I've tested this at a few shows now using the stereo out on my mixpre and it's done a really nice job with Metarecorder app. If you want to get into streaming or want a super low-pro recording option and have a battery box, I would definitely recommend this piece of gear.
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I actually joined taperssection to give this review of the AI-Micro, since this thread is where I learned about the device.
This is a fairly in depth review, and might save a few people from having to email Røde support, which takes forever, and they really don't answer more than a few questions, just the ones that are directly related to them selling stuff, they don't even answer specific feature or device or software questions. But they do answer, eventually, but save yourself the bother, this is roughly what I have found so far:
For TRS stereo powered microphones, like Sound Professional Binaurals, going into a battery box, you need the Røde SC11 splitter TRS male > L/R TRS male cable. I tried it without it, and as Ozpeter notes, got only one channel of the stereo. Røde's documentation is slightly wrong because they say a powered mic won't work at all, this is not correct, one channel works. And both with the splitter Y cable. I believe you can use other true trs > L/R splitter trs male cables, but I have so far not been able to find any except the Røde one. That's a good quality cable, but at least 2x too long for my needs. If you use trs binaural mics, then just consider the cable as part of the purchase price, which brings it up to $95 US currently. I don't believe they offer trs female > trs male l/r cables, which might matter on some battery boxes, means you'll need one more adapter.
Battery box works fine in this setup, as long as everything is TRS in and out.
I also tested an adapter cable TRS male > TRRS male and that didn't work at all, no output from the Røde, in case someone thinks that is worth trying, it's not.
To set the input configuration, you have to use the Røde Connect app, plugin the device to phone or computer, select the configuration you want, which is:
1. merged: (input 1, 2 merged into mono)
2. split: inputs 1, 2 forming stereo in - this is what you want for TRS stereo powered male in.
3. stereo input 1: I think this may only work with Røde microphones, or a specific configuration, that supports TRS or TRRS it says, auto detect. This is the one that gives only 1 channel with powered stereo trs mics.
Disable all high pass filters etc, those are only intended for stuff like podcasting.
You can also disable the live monitoring feature in the headphone out, that's useful I think since unless you are doing live monitoring while recording, that's just extra processing being done by the preamp, so disabling it is probably a good option for most recording situations, means the circuits do less work, would turn off at least part of the the DAC circuits I assume.
The levels I don't believe matter since the audio recording software will change those anyway.
The usb device will retain this setting if you use other audio recording software on your phone or other usb input device, but you have to use the Connect app to set these values initially. It's easy to verify it's working and set correctly on your recording software since if it's not, only 1 channel will work, or it will show as mono.
Also, it's worth updating the device firmware when you get it, first thing. You can do that on the Connect app too. Bugs that actually impact recording might have been fixed, so worth having current firmware.
I suspect the failure to handle powered stereo TRS in is a hardware, not firmware, issue, and is likely to not be changed in the future, though you never know, if you keep emailing them about this lack, maybe one day they will reconsider, but not if this is what works on their stereo mics.
Since the Røde Connect software seems to have problems with screen off behaviors, I never tested that at all, not interested in losing a recording due to undocumented behaviors of unknown software which was clearly not written for live music recording situations. I run it into an android phone with USB Audio Recorder Pro, which works well, stereo inputs recognized, all works fine. The only small glitch I can find is that USB Audio Recorder Pro does not seem to retain the bit depth setting from previous selection, so you have to remember to set it to 24 bits if you want to do 24 bit recording before you start each recording session, it seems to default to 16 bits on start/detection. That audio app also records direct to FLAC, which is nice, saves room, and leverages the essentially free cpu/battery/storage on your phone, which is there anyway. Only real downside is app gain sliders are very fiddly/sensitive, but you can use a double tap mode to manually type in the db value, but that takes longer per channel, and there is no global gain slider, just per channel. I find this awkward to use in a live recording setting.
It's worth also noting that if you have a decent phone, you have massively more compute power available than any external recording device has, more storage, and more battery life/capacity. Recording life is massive, I have never noticed any significant battery charge drop recording with this app, maybe 5% or something for 3 hours, it's negligible. Leaving the screen or bluetooth on uses much more battery than the recording software itself when recording does.
Important: I had a crash once on this software while recording and taking pictures with the phone. Their docs say to turn off all networking, bluetooth, etc, and to not use the phone for anything else when recording. Airplane mode, that is, including bluetooth, and no camera. This is correct, I can confirm that you can suffer a crash if you don't observe this warning. The phone should only be recording, nothing else.
I'm not actually clear about the comment above re 48 khz not 'being enough', that yields 24khz frequency response, which is probably a solid 8 khz above what anyone here can hear, and 4khz above what the best human can hear, and almost certainly the max of what most mics in a live setting can capture, so it's hard to understand what would be lost by not having 96 or 88.2 khz sampling rates, for the master, particularly in live recording situations. In post, yes, those might have utility, but not in the recording itself. Unless all the digital audio stuff xiph.org etc publish is wrong, and all their resources are wrong, which I honestly doubt. It's certainly not a realworld negative. 48 khz was a good sampling rate choice I think, covers native video sampling rates, native Opus sampling rate, and isn't that big a difference in recorded file size from 44.1, but avoids the up/down sampling math issues of 44.1 khz.
I'd say the Røde so far is checking all the boxes, the 24 bit gives enough headroom for > 120 dB recording situation (which is already too loud), drops the noise floor a bit I believe as well, which was my main reason to want to check it out. Also makes clipping less likely, and minor gain level errors matter less, which was an issue I was hitting with 16 bit now and then.
Also I'm assuming they use a better preamp internally than most generic usb audio devices, almost none of which support stereo mic ins anyway, which can make a difference.
It's also tiny, and has basically perfect inputs (except for not handling powered stereo TRS in, which would be nice), and offers very flexible cabling options. I was able to significantly shrink the physical bulk of my cabling with this device.
I haven't done enough recordings with this yet to get a feel for if the preamp quality matters in the real world, to me, the mics are going to matter more almost certainly, but it doesn't hurt having what is probably decent ADC chips, hopefully decent anyway. The price to me suggests a few steps up from standard USB audio devices. I'd been initially looking at something higher end like Dragonfly USB audio devices to see if I could find a better ADC preamp type thing, but I was surprised to find they don't support Mic in, let alone stereo usb mic in. So the Røde seems like a good step up for micro recording preamps.
There's kind of a lull in shows I want to record so I won't be able to really get a feel for this device for a month or two, but so far the setup and shrinking and quality boost seem to be everything I had hoped for. Initial impression made me decide to upgrade my mics, since the preamp will almost certainly not be the problem anymore in the chain.
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Thanks for your detailed comments on this little device - I've not got much to add because one way or another I've not had a chance or need to use mine much. But it's worth having in the 'toolbox'. As for sampling frequencies and perceptable audio quality - well, that's been a matter of intensive discussion for a great many years, so... I'm not going there! But I guess I could say that at 73 years old, my ears are past caring!
I'm sorry that you didn't have a good experience with Rode support - personally I found them to be really helpful and motivated, but that was dealing from Australia with the Australian branch of an Australian company, which probably smoothed things out somewhat.
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Companies can decide for themselves what priority to give support. You can delay 1, 2 weeks, then respond to only 1 of maybe 6 questions, the one involving selling something you make, or you can, as Sound Professionals recently did, answer within 12 hours, on the weekend, and answer 6 questions completely and accurately. I then can decide who to support in the future based on this experience, so that's up to the companies, not me. It's the rare person who will ever complain or be turned off by getting prompt responses that are complete, so that's a sort of basic decision you make as a business. Needless to say, Sound Professionals rang up a sale a few days later, and, not satisfied with their initial excellent support, found a way to be even better after my order. I don't believe I ever received a response to my follow up response, which, oddly, Røde themselves had requested. Thus my conclusion, don't waste your time. This is their decision, not mine, to be clear.
For a corporation that want's to reduce support expenses, all they have to do is make better documentation, that is complete and robust, it's a basically one time expense per item if it's well done, with occasional updates. I think all the questions i had could have been handled by better documentation.
But I always buy from cottage industries if I can, the experience is almost always far superior, since you're usually dealing with a very small group of people, sometimes just one person, who seriously cares about what they do, not someone on the job, salaried, under pressure to meet deadlines etc.
On a technical level, I would like to find, if available, the actual real tech specifications on the AI-Micro, all I found was the generic consumer stuff, which is not really that useful. But it's a rare USB audio device maker in this price range that supplies that type of specifications, but it would be actually useful so we could compare much higher end audio preamps like MixPre or whatever with the AI-Micro, though my view is, once you get to decent quality, the inherent dirtiness of the audio in a live recording environment makes such subtle things largely irrelevant. Probably better to test better mics at that point, which is what I am doing for my next recordings.
If one had money to burn, one could pop open the case of the AI-Micro to find out what chips they are using, which you could then find the specs of online, but unless you were going to use the guts to make a hybrid battery box/preamp usb device, that would be an expensive learning experience.
There are probably not that many ADC chip makers in this price range is my guess, and stereo 24-48 capable ones even fewer, which would lead me to speculate that either the AI-Micro is using something usually found in higher end preamps, or is using something from lower end ones, would be nice to know. Or it's an actual midrange one made just for this type of device. Or a full system on chip type thing, I'd be curious to find out what's inside one.
But I completely agree with one of the original observations in this thread, it's amazing to look at the quality vs price today vs the past, I suspect strongly that nothing portable, and maybe even nothing analog at all, could match something like this little AI-Micro in the past. With no real specs, that's just speculation though. With a phone doing the recording, you're talking about running a literal super computer equivalent in the past in your pocket, with a portable battery that lasts 1, 2 days, and storage capacity in the days, not hours. And almost no degradation from one end of the digital chain to the other, that is, once it hits the ADC, it's just bytes streaming through circuits.
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Is this Rode AI-Micro soundwise a huge improvement compared to the previous type SC6-L ?
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I doubt it.
https://edge.rode.com/pdf/page/1864/modules/4708/sc6-lik_datasheet.pdf
https://edge.rode.com/pdf/page/1871/modules/4638/AI-Micro_datasheet.pdf
As you can see, you can't really compare any values between the two datasheets, but unless they got a new ADC chip for AI-Micro, I would not be surprised if it's the same chip inside. This also depends on the age of the SC6 device, if it's much older, it probably has a different chip, but that's just a guess. Microchips tend to get better for the same price, if it's an old device, it's not a terrible bet that the chips in AI-Micro are better, but they could be exactly the same for all we know.
This is the kind of thing that it's virtually impossible to actually AB test since you'd have to be recording from the same mics at the same time at the same show through the two ADC devices via splitters out of the battery box at exactly the same levels to actually determine if there was any audible difference. The only difference I could see in specs is that it appears to say that the SC6-L is powered via iphone TRRS out, but iphone doesn't have those anymore so that might be an error. But if it's not a USB/USB or lightning/lightening connector, and is actually not going direct to USB type connection, but is being translated back to non digital audio before being sent to the phone, then there could be a significant difference. The AI-Micro definitely is pure usb to usb, meaning it's not being translated back to analog audio after the inputs hit the device, which is what you want, since otherwise you inject a DAC on the device, and another ADC on the phone, which is not good. But Rode doesn't give you much to go on in their docs, so I'm just guessing.
My guess is you'd never hear a difference though if both are sending digital data to the phone. For me, I just assumed that it was likely the AI-Micro uses a better ADC chip than my previous preamp device, since it costs 2x more, and output 24/48 instead of 16/44.1, making it somewhat likely that the chips in the Rode are better quality than what I was using previously. It would be nice to not guess but to actually know, but that's asking too much from what are essentially mid priced consumer devices not really intended for this type of recording purpose I suspect.
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Thanks for sharing your thoughts on this subject! Just down I came across this on the rode website:
https://rode.com/en/interfaces-and-mixers/ai-series/ai-micro
“ While similar in design and concept to the SC6-L, the AI-Micro has a few key updates that make it far more versatile, including a universal USB output for use with Android smartphones and tablets (and iOS devices with a Lightning port like the SC6-L), as well as computers. It has also enhanced inputs for use with a wider range of microphones and is compatible with the RØDE app suite for accessing advanced features, on-the-go configuration, and broadcast-quality recording on any device.”
Nothing about sound quality improvements so maybe indicating this is basically the same unit . So the biggest change must be that it’s not limited for use with Apple devices only
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That was my suspicion. The reality of actual chip making is that it costs a lot of money to design and implement and fab a chip, and smaller companies are very unlikely to be getting custom chips made, they go to the same probably shenzen based wholesalers everyone else goes to, and put together their stuff based on what is available at that time. I found it odd that the actual listed specs on the two devices didn't match in type or or syntax, but used different terms with different numbers, making it basically impossible to really compare them.
I like the very compact packaging of it, and it has better specs from what I can see from a similar device, the Boya DM20, which bottoms at 45hz, but has the same 16/24 48khz capability. Overall the specs make me think the Rode are roughly what they claim, decent quality and probably better than generic average, but with a few significant unknowns, which some simple documentation updates could easily resolve. It's odd to see audio equipment companies not list standard audio data however, but documentation is tedious, lol, but much less so if you get paid to do it.
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There may be a real issue with the Rode AI-Micro, I need to do some more testing, but I tried it last night with some new gear, and it appears it may possibly be engaging some type of limiter internally, though I can't be positive about that. It could also be the recording software, maybe, but hard to determine without that sound pressure level. I'll post back if I find anything conclusive. I can say that USBAudioRecorder Pro can't be used with more sensitive microphones because it only has positive, not negative, gain, which leads to massive clipping, or what should be clipping but is being flattened by something just prior to that point. I'll try to pin this down to either the rode or the software if I can.
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>but I tried it last night with some new gear, and it appears it may possibly be engaging some type of limiter internally, though I can't be positive about that
:o that would be a bad feature
Please keep us updated !
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Damn. I wonder when it was kicking in?
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If otherwise it would have all overloaded, it is still better than a failed recording. Sounds like you need some kind of pad between those mics and the rode.
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I just tested mine out with the Rode Reporter app. Close to clipping, I didn't notice any limiting and was easily able to push it a bit further into brickwalling.
Have you tried it out with the Apogee Metarecorder app? I've had good test recordings patching out from my Mixpre 6 using that app.
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Appreciate the responses. I first want to give the USB Audio Recorder Pro guys some credit, i've sent a few emails trying to track down the source of the issue, and they have answered several emails promptly with actual attempts to get to the root of the issue on their part. Which is particularly noteworthy since he told me this morning no changes in usb audio recorder have happened since october 2021, since they have largely shifted development to their DAW, Evolution.
They say that USB Audio Recorder Pro, which is also the engine for their DAW's USB audio input, does no processing on the incoming usb signal beyond converting it to the selected codec type.
So unless Android is doing something horrible, that seems to rule out the recording app.
The USB Audio Recorder guy also said that RegForge II while it pretends to offer a negative gain control, actually all that does internally is drop the gain on the clipped signal, so it no longer appears to be going into the red, but it's not actually doing what it appears to be doing.
I found a way to test at adequate db levels (mics 1 foot from speaker cranked REALLY loud, lol), that gets me into clipping territory, am going to check.
One thing I can already say is that the Andrea Electronics USB Audio device is delivering FAR lower output levels than the Rode. I tested both just now at 0db gain with the same source at the same volume, and there was a large difference in levels between the two, so all is not as it appears here. I am afraid that the Rode may be applying some type of real processing internally to the signals, which would make it a huge no go for live recording.
This issue appeared because I am testing these mics:
MS-BMC-3 – Ultra-low noise Binaural microphones
Pickup Pattern: Omnidirectional
Frequency Range: 20 Hz – 20,000 Hz +/-1dB
Sensitivity: -32dB ±3dB @ 94dB SPL
S/N Ratio (1kHz, 94 dB input, A-weighted): 75dB
Self Noise: 19 dB SPL
Maximum SPL at 12vdc: 120dB
Dynamic Range: 119dB, 1 kHz at Max SPL
Impedance: 2.2 kOhms
Voltage range – 2vdc – 12vdc (48v on XLR version)
Current draw: 500 µA
Which are a big jump in sensitivity and s/n ratio, and dynamic range.
Signal To Noise Ratio: 60 dB, kHz at Pa
– Dynamic Range: 81dB
– Frequency Response: 20- 20,000 Hz
– Open Circuit Sensitivity: -42 dB (5.6 mV) re 1V at Pa
– Maximum Input Sound Level: 110 dB SPL, kHz at 1% T.H.D.
– Flat frequency response
– Omni-directional pickup pattern
those SP-BMC-12 mics did not cause any issues with the Rode and levels in a live setting, but they are much less sensitive so I assume the voltages are simply lower. I wanted something that could handle higher sound pressure levels due to some issues I had recently where the club levels were simply radically too high (deaf sound engineer issue, too loud almost always means they are losing their hearing)
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DavidPuddy I was actually going to ask for suggestions of other recorder apps to try, all the ones I tried are absolutely awful . Apogee appears to be IOS only however. But it sounds roughly similar to USB Audio Recorder Pro, but if they aren't developing usb audio recorder pro any longer that suggests a worrying prospect that there might not be any usable alternatives for Android, unless someone can suggest one? Testing these things is really time consuming, and it's very hard to hit the actual sound pressure levels of a club in a home system, so I can only approach the levels, I can't quite hit them. Can you generate clipped master audio file, wav or flac, recording from the Rode? Particularly massively clipped/red lined.
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grawk, no the recordings is totally failed, something simply flattened the clipping, it sounds horrible, and the only logical suspect is the Rode unfortunately at this point since USB Audio Recorder Pro confirms they are not doing any active processing on the incoming usb stream. it was absolutely flatlining in the red during the recording, and the audio should have appeared as almost all red in Audacity, for example, that is, clipped, but it was totally flattened, which means I couldn't even readily see it was clipped then pushed down probably .1 or .2 db to be just under 0. This is how I tend to fix mild clipping too, but I don't want unknown circuits of unknown quality running inside unknown software to be making this decision for me, it's almost by definition going to be doing a worse job than any real audio program would do in post.
I could see it right away on the wave forms, they were massively flattened, as a recording, it's what I would call 'for completists only'.
Any hint on the pad approach?
Currently I do not trust the Rode, at least not until I can really pin this down.
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This failure is very difficult to track down.
One of the set of questions I did NOT get an answer to from Rode was specifically about what is running in their usb device and what is not, that is ambiguous, it might be running some effects, or those might be running in their recording app, they didn't answer that question so it's uncertain. I asked twice, and that's enough.
I think because there are too many variables, I may need to go another local live show, ideally loud, and try this again with the Andrea USB device, and see if the problem persists, including deliberately clipping a section so I can see what happened to the wave form.
The only positive was I was really just going to record this show to test the new gear, and I didn't like the bands that much anyway, so it wasn't a loss like losing a real band I really want to capture, but it did send huge red flags up for me that something is not what it appears.
The problem seems to be that a lot of these devices are aiming at non audio types, podcasters/youtubers seems to the target market, so they are really dumbing down their docs and their interfaces, to a somewhat absurd level in my opinion. Which makes it really difficult to figure out what is going on.
My fear is that the Rode is actually compressing the signal, not just limiting it, which actually would be what many youtubers would want, but not as a default you can't switch off.
But I am mystified, because every time I've pushed usb audio recorder pro into the red, it's resulted in clipping on the master audio file, but this time it was smashed against the red max line, and the audio is totally unclipped, but massively compressed.
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Maybe a 3.5 mm female coupler and one of those 3.5 mm cables pads that they use for cameras might work to bring down the signal. 20db pad and boost in post?
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I'm about 80% sure that the Rode is doing active processing on the audio.
Keeping in mind I didn't touch the position of the mics, and the same recording software was used in both cases, there is a fairly radical difference in the frequency analysis of the two sample recordings.
The Rode is definitely flattened in terms of spectrums, and actually sounds almost tinny compared to what I believe is a fairly neutral Andrea usb device.
There appears maybe to be an active bass cut in the Rode, not sure, but records at -14db at 79hz vs the andrea 58hz at -8 db, which if I remember my digital audio right, means the bass peaks not only in a different range, but at about 1/2 the voltage/db.
I could not drive either into clipping range however, maybe if push my system a bit more and move the mics closer to the speakers I can get it there to see if I can activate that compression.
Basically, in this simple test, with everything roughly the same except the usb audio devices, the andrea sounds like the recording I was recording, and the rode sounds like crap. Literally, there's no need to do a real ab test on it, the rode is definitely altered, and I believe at higher sound pressure levels is doing even more active stuff.
This was exactly the question their support guy would not answer, and I believe now I can see why he totally avoided answering it.
While the 48khz and 24 bit is nice, until I can get it actually verified what is going on with the Rode, I'm not going to use it in a live setting except for testing.
I think what I'll do is bring both a test show, and record about half a set of the same band with both so I can compare.
But so far my suspicions appear to be confirmed, I think maybe rode is too focused on their target youtuber audience and has done some really nasty stuff in their device. Wish I didn't have to guess, would have been easier if they had just answered the questions, but currently I'm considering this a no go.
Not conclusive, but the first true ab test I've just run delivers beyond terrible results, this would instantly pass the 10/10 abx tests hydrogen audio people want to see, I don't even have to bother testing it at all it's so obvious.
This type of testing is difficult to do however, and there may be some other factor involved, but this difference I see/hear cannot come from Android, the recording software, the mics, since they are the same in both cases.
I'll maybe do another test with their rode connect and reporter apps to confirm/deny, but it's also possible that rode is doing something that only their apps control, and it's not defined in the usb output data, which again makes this device a no go because I don't want a usb audio device to be running any logic beyond converting the stuff with ADC to digital format.
This is however the risk with all these consumer type usb audio devices, their target audience are normal consumers whose ears can be easily tricked by basic audio manipulations into thinking the usb device sounds 'better' when it's just a bit of audio foolery running.
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I tried a test with Rode Reporter as well, but discovered that their fondness for removing any real technical data from the interface makes it almost impossible to do a true comparison.
Their gain slider appears to not be connected to the internal gain of the usb device on reporter, which I confirmed by running it without the rode device, at which point it records from the internal phone mics, and the gain slider isn't related at all to the main gain sliders of the usb device.
When I tried recording at 0 gain to test this it basically almost shut all the audio off, so it's not doing the same thing as the external recording app is doing.
I also believe that what rode says about using rode connect to disable or enable the bass cut is not correct, because it appears that the bass cut is active unless you are in the rode app.
All this makes this way too untrustworthy to ever use on on an important recording, so I think I'm going to give the rode a pass, and accept that the red flags I got from support failures were because of these issues, at least as a working hypothesis for now.
The configurations are far too barren as well to really figure anything more deep out, I couldn't even find where it stores its audio files, the only way to find them was to export them via the share/copy, then copy to a directory. RecForge had similar absurd behaviors by the way. In my view, these are toys, not real tools, at least that is my current conclusion.
If there's something I'm missing, chip in and correct, but currently I am not going to risk any recording with the rode, at least not until all these questions are conclusively answered. I don't trust this device.
I'm starting to wonder if some audio oddities I had in a recording that should have been quite stellar recently with the rode and my old mics may have been related to some of these issues, but I'm not going to take a chance recording a band that may only come once in 2 or 3 years, or longer, with this device until all these questions are totally clarified.
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One more test: same recording, same mic position, this time with the rode reporter app, with usb gain set to 0, as with the other two tests, and the recording gain set to 100%, which I believe emulates the recording settings I did on the other tests.
The result: absolutely shockingly horrifying. Beyond belief. complete garbage recording.
Note that their vu meter thing is very poorly made, in keeping with the toylike nature of their app, and basically only is green, and below it, is a graph sort of thing that shows where the red line is. The fact they couldn't even figure out how to make a standard green/yellow/red type vu bar is in a sense all I need to see.
The recording is radically compressed, and appears to be using some type of logic that kicks in the compression actively, but there are simply too many unknowns, so I'm steering clear of this device, until at least they publish clear statements about what does and does not happen internally with their device, both with their own software, and with 3rd party tools.
I believe I can confirm that the bass cut did not happen with the rode software but all kinds of other horrific things do happen, which means that their docs to use rode connect to disable bass cut are false and untrue, at least that's my tentative conclusion.
This one had promise and was worth I think testing, but I am avoiding consumer toys like this in the future, but there was no way to know this without testinig it, so I think not a bad $80 spent, because if it worked as advertised, it would have been close to perfect, but these results are so radically unpredictable I can't consider this a safe tool to use for actual recording purposes.
I suspect most of these issues can be resolved with a firmware update (I'm using the latest firmware) because these are mostly software related problems, not hardware, so if they would accept feedback and fix this, in the future, this device might become useful and usable, but not as currently programmed in their firmware.
I'm glad I tested this more, but these results are so awful that I have to conclude this device is only intended to be used in the closed loop rode system, with rode mics, and rode software. If you get better results, there may be some other variables, but make sure you have the latest firmware updates, it's easy to install them, because they could have created these issues recently, just like they could fix them with future updates.
I do want to give a nod to Sound Professionals, who gave awesome support, as did USB Audio Recorder Pro, so I know where my money is going in the future.
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Maybe a 3.5 mm female coupler and one of those 3.5 mm cables pads that they use for cameras might work to bring down the signal. 20db pad and boost in post?
Am I missing something, brother doomed? Have you tried an attenuator cable on the input, as fireonshakedownstreet suggests? ???
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yes, the problem is with the actual device, its doing something to the audio, I just tested that today and it's almost certainly corrupting the audio. The higher the input levels, the worse the corruption. Though it's not for sure yet, I am also going to test it straight into a real system with Audacity as the recording tool to see what happens there, just to rule out Android itself. But USB Audio Recorder Pro guys told me they make their own usb driver, so ideally, android is not involved, but it's hard to know with those types of closed systems.
My current guess is that the 'AI' in AI-Micro stands for their attempt to have 'smart' sound processing, and that attempt simply should be terminated with a firmware update.
It's not a question at this point of adding a pad, anything I send into that device corrupts, I verified it with an ab test against a known good usb audio device I've used previous to the Rode. Since that test was done on my home system, which can't reach those clipping sound pressure levels, I was able to see what the device does basically on its own, and it is bad. The only thing I want a usb audio ADC to do is convert the incoming analog, convert it to digital, then send that down the usb to its destination. Much more than that is going on, and their docs appear to be wrong, or they messed up the firmware, so shutting off the high pass filter in their app does not appear to be shutting it off for the 3rd party audio tool.
I can't guess what is being done on that device, but I won't trust it for anything until either they issue a real firmware fix for these issues, and make it work correctly with non Rode software, including disabling any and all active processing of the audio.
The device is also putting out roughly 10db more than my previous usb audio interface I'd used with good success, and how or why that can happen is beyond me, since both are receiving the same input signals during testing. I don't know the ins and outs of this type of device design so I don't know where the issues are really sourced, but i'm not risking any show I want to actually record on such an unpredictable device.
I'm going to test the revised setup at the same venue on saturday, that will tell me pretty absolutely if it was the rode at fault since I'll be removing that from the setup, though I may bring it and swap during a band I don't care about's set, just so I can get a really accurate comparison at the same venue on the same night.
I'll post an update after that test, but these things aren't easy to track down conclusively, but right now, most of my suspicion is on the rode, because it's doing things that should not be happening, and they are verifiable and readily measurable. It's possible that they messed up the firmware, but I don't really see how, since I tried this recording on their own app, to the same results. Which suggests this is intentional, and someone's notion of a good idea. I'm also suspecting the initial reasons they didn't answer my questions twice about this stuff is they don't actually want to admit what they are doing, though that's just a guess.
One of the really terrifying things I saw, though I have to retest to make sure, is that during a roughly 30 second test recording, it was actually actively and dynamically adjusting the compression levels, you can actually hear it happen during the section, and see it in a wave editor. I believe that's the 'AI' part of the logic, though it's just a guess. But I don't want to push my speakers that hard much more, they don't like it, and neither do I, so I may just put this device away and let other people figure it out, and use something I know works.
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That sound awful! Thanks for your work, doomed.
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I'd like to do more work on this in terms of more testing, but as mentioned, neither my ears nor my speakers like being pushed to that level. I'm glad I captured the two main tests clearly however.
The more I think about this, the more I believe that the 'AI' in AI-Micro stands for a horrific notion of trying to make the device 'sound good' to amateurs. Even the higher db output level fits in with that. I believe it was John Watkinson in his The Art of Digital Audio that noted that in listening tests, users almost always think the one that is 'louder' sounds 'better'. It could have been someone else, but same level of understanding. Compression on vocals also is a trick to bring things to sound 'good' in for example a youtube streamer's voice, etc.
I will however basically know for sure after this weekend, because it will be the same venue, same sound system, similar type of music, at least close enough, and a known recording spot. If the Andrea unit delivers with the new sensitive mics a totally fine recording, then there is no doubt.
It's my understanding that in a club setting, 96 db (aka, 16 bit) is all you need from noise floor to house sound pressure level at x distance, where x is far enough away to be reasonable, that is, your head isn't stuck into the cabinets, from stage speakers.
I need to get this totally solidified by next month because a real band that rarely comes is playing, at what are sure to be challenging sound pressure levels, so this all needs to be solid by then. Actually another guy is coming earlier too, and he almost never shows up playing live anymore. Saturday's show should show me all I need however since if that gets pushed into clipping territory I will have to look into getting a pad for these mics, which is/was a suggestion I appreciated, I probably didn't make that clear.
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To be honest, mine has been in a drawer for some months simply because, well, I don't think I actually needed it, and lack of functioning stereo input for PiP mics is a bit of a dealbreaker. But I'll see if I can test it in the next few days to see whether it too gives bad results with a beefy input. One thought is that Android devices can be surprisingly incompatible with external stuff (eg something might be fine with one phone but not with another phone, for no obvious reason) - have you tested it with another phone at all? Apologies if you've already mentioned that.
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Thank you.
Impressively solid testing and very valuable knowledge.
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justme, I wish I could do more testing, but if I posted screen shots of the two frequency graphs from the recordings, you'd instantly see the difference. Definitely not in the faux audiophile expert realm that is, 'the sound stage is more balanced and lean yet crystaline in clarity and presence' here, it's: one sounds like the recorded source, and one sounds like crap. With the graphs showing the corruptions clearly.
Ozpeter, one thing that USB Audio Recorder Pro does is they made their own usb audio driver, probably based off the Linux kernel's normal driver is my guess, they don't use the usb audio driver of Android. This is actually quite meaningful, because if that was not the case, then it could be different Android versions shipping different or varying usb audio drivers, which would certainly result in such issues. This usb driver and logic is used on their Evolution DAW as well, so it should be working for a while, I hope.
But you are quite right that this is unfortunately not 100% knowable since Android is something of a blackbox sadly, except for the fact I have done many fine recordings with the other usb device on the same phone at high db levels without a single issue like this, when I have gain too high, the recording clips, period. I cannot make the Rode clip. I've had issues at high db levels, but they are what you'd expect from either overloaded mics or overloaded circuits in battery box or elsewhere.
One reason I don't actually think it's even worth testing the other usb recording apps for android is they are all worse, worse interfaces, worse usabilty, worse documentation, some even try to force you sign up to their 'cloud' stuff (BandLab) so I couldn't even test those at all, but I assume they are as bad or worse. The dolby one was particularly terrible, which was a bit of a surprise, that one doesn't even pretend to not do dynamic processing, in fact they brag about it, and it's clearly not something that can be disabled.
I could test another round recording straight to a real computer, same tests, but as noted, my speakers just don't like going to just below small club levels, and blowing their woofers isn't worth it to me since I already see the non ambiguous data in the recordings I tested with.
Everything points to Rode making very bad decisions about their firmware, and also to a certain NIH (not invented here) attitude towards purchasers of their AI-Micro, since none of those filters or settings should be active in the first place when not going into a Rode app.
The clear presence of a bass cut as well means I can't even trust their own docs that say clearly that if you disable high pass filter in their app, it will disable it on the device for 3rd party apps as well, which does not appear to be the case. Or they messed up their firmware, and it's supposed to work, but doesn't, it is too hard to tell to be honest, and not one of these issues should exist on what is supposed to be a quality device.
I'm keeping my fingers crossed for a few things now:
* The old usb audio interface performs as expected (and given it's coming in around 10db or so under the Rode, which is roughly the range that was being redlined with the rode, I have good optimism there). I'll know this tomorrow.
* A serious usb DAC maker, like Dragonfly, decides it's worth making a quality stereo mic input ADC. This is unfortunately a very fringe requirement, so the market is clearly not very big, but I'm going to keep my eye out, as we see with Rode, the chips are there, but all that's needed is either for them to wake up and disable all their processing and deliver clean audio via a firmware update, or for another vendor to make a stereo 24/48 capable ADC using the same chips, unless the processing is built into the chips, which I suspect is not the case. There is nothing in the tech requirements at all that makes this not possible, so it's just a matter of someone doing it, and deciding there's enough market to make it worth it.
After this experience, I think I'd definitely bump up my maximum price I'd pay for such a device however.
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After the live test, I can confirm almost certainly that the AI in AI-Micro is, first, a nonsense marketing term, and second, points to processing triggered by difficult to determine events. This logic is either baked into the chips, or it's running in the operating system/audio software blob we call 'firmware', or possibly a combination of the two.
There's a few unknowns, first is if moving the gain slider to 0 is what triggers increasingly extreme processing, or if it's gain plus incoming voltage that triggers it. This can be determined by a lower volume test, which I'll do when I have the time.
In other words, if I can demonstrate to myself conclusively that the AI-Micro applies no processing at higher gain levels, say, +8-12db, then it could be used with an attenuator. Sound Professionals sells several options, which I will look into, but that would always require that you get it right to start in terms of the attenuation and the gain levels on the Rode.
I'd say tentatively if you see significant red in your recording app VU meter, you can throw away the recording, it can't be fixed, and will be a full fail.
I've done a recording with the rode at lower input levels, and found some things I found to be odd, but didn't give it much thought at the time, since I thought it might have just been the room, but now I'm not so sure, those could have been milder applications of the dynamic processing going on.
Then there's that largely inexplicable roughly 10db or so boost applied to the digital usb output, which makes no sense unless you are trying to make it sound 'louder' to the person recording it.
I believe I can nail down a few of these questions crudely, but not with certainty, because if it's a progressive action, that is, gain controlled, or gain plus input voltage controlled, that would suggest that it's always applying it to some degree.
I would not use this device for any live recording until these questions can be unambiguously resolved.
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I believe the AI stands for audio interface, not artificial intelligence.
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Sounds plausible, though at least there would be an excuse for those behaviors if it meant Artificial Intelligence-Micro.
I'm slightly curious to see what it does under varying loads, so I'm going to run a few more tests on it, a/b'ing it with the reliable consistent interface, I'm actually curious to see what it does and how it does it, and if I can determine if there is a point where processing stops and straight audio comes through, or if there isn't.
Just to be sure I hadn't missed anything, I reread their main page, but nothing beyond a strong focus on podcasting etc appears.
I'm really hoping this changes (via maybe a firmware update) to be honest, because the device itself is very promising, but not as long as it tries to be 'smart' when not asked to be. But I think youtubers and podcasters are their primary target market, think dual mics in an interview or conversation setting, despite their pages mention repeatedly of 'high quality' sound etc.
Or it could just be a mistake and a failure to test adequately, hard to say really, too many unknowables which can only be determined via testing and analysis. which is kind of tedious to do, though educational.
I don't think AI was an accident in the naming though, every usb audio device out there ever has been an audio interface, but non have called themselves AI-xxxx, and none that I know of do this type of active processing.
Simple documentation of features would remove all the guesswork, but I'll plug away at it some more, but not in a live use setting.
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Rode calls them the AI series, and yeah, that might be a marketing play on artificial intelligence, but all they talk about is audio Interfaces. The predecessor that the AI-Micro is a smaller version of was the AI-1. Nothing suggesting any intelligence in them, other than "auto-sensing" TRS and TRRS.
https://rode.com/en/interfaces-and-mixers/ai-series
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Just a quick heads up, I was looking up the specs on the Andrea usb audio interface, and they are having an end of year half off sale, and also I discovered that they offer a stereo 1/8" mic only interface, no headphone out, no dac, with better specs. It's only $20 now (december 2022), but they only ship priority mail, at $10, so if you order 2 you'll get a much better deal. I've used their headphone/mic unit with very good success, and this one is better from what I can see. The headphone/mic one is also on sale, half off, about $20 too. You won't find a better deal than this ever on a stereo mic supporting usb audio interface that actually works.
I've never seen the 48khz supported so far on recording apps, but that may be simply because they don't know about this device, which is not common. Not that 48khz will do you any good with 20-20,000hz supporting mics.
https://shop.andreacommunications.com/usb-ma-premium-external-usb-microphone-adapter/
2 Channel Stereo
48K/44.1KHz/16K/8K
0-70°C
Supply Voltage: 4.5-5.5 VDC
Total Power Consumption: 120 mA
Bias Voltage: 2.2V via 3.3K Resistor
A/D Conversion Resolution: 16 bit
THD + N: -90 dB
Supply Bass Resistor: 2.2K ohm @ 3.3 VDC
Frequency Response: 20-20,000 Hz
Input Range: 0-1.25 Vms
Dynamic Range: 96 dB
Record Gain Range: -6 to 33 dB
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A small update in the Røde testing. I am frankly puzzled by my latest lower volume tests. I did another a/b recording, same source, same mic position, etc, between the AI-Micro and the Andrea SB-SA. You may recall that at high db levels, the AI-Micro is delivering almost 10db more output than the Andrea, making it unusable in a live setting without an attenuator / pad, so I expected to see similar results in normal listening level tests. Such was not the case. Whereas at high db levels, the AI-Micro had much higher output than the SB-SA, at lower levels, normal listening on stereo, the AI-Micro needs much MORE gain to match the rough recording levels. This is clearly impossible if this was a linear circuit, so it clearly isn't, which was already obvious from the original set of live and test case results.
As well as some other oddities which I honestly cannot understand or explain in terms of the normalized overall db levels per frequency range.
So this device is fairly radically unpredictable, whereas the SB-SA/SB-MA act totally linearly, utterly predictable, those clearly do no clever tricks to the audio at all, and are what they claim, a usb audio interface, period.
The AI-Micro is most definitely not linear, and is doing a lot of things I cannot explain or understand, and because of this, I view it as far too unpredictable to ever use in a real live setting where the recording matters. There's also the question of the bass cut apparently kicking in after being disabled in the Rode Connect app, which is supposed to disable it in the firmware, but as far as I can tell, that bass cut also seems to activate dynamically at higher db input levels, but it's all a guess.
One thing I was testing, which I was largely able to determine, is that the bass cut is activating at higher db input levels, and is not active at lower db input levels. But I'm not going to push my gear to find what point that kicks in automatically, and if it kicks in with an off/on manner, or if it kicks in progressively.
If this is not burned into the chips of the AI-Micro, this anomalous behavior could be fixed with a firmware update, and I hope it will be one day, but as it is, when a simple test fails to show any type of consistent behavior between db levels, that just makes the rode a no go for me. For what it's worth, from what I can see in the wave forms and frequency graphs, at lower db levels, the rode requires MORE db gain, not less, to match the levels of the SB-SA, the opposite, that is, of what happened at high db levels. The wave forms and frequency graphs at lower db levels do appear to roughly match, which was not the case at higher db levels, but I'm not going to subject my system to any more of those high db tests. There's also another odd difference which I simply do not understand and can't explain, so I may need to learn a bit more about what Audacity is showing me before commenting on that part. But it should not be there, if I understand the stuff right, which is not a given.