Topic: Rode AI-Micro Ultra-compact Dual-channel Interface

[doomed]

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.

[scottE]

Is this Rode AI-Micro soundwise a huge improvement compared to the previous type SC6-L ?

[doomed]

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.

[scottE]

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

[doomed]

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.

[doomed]

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.

[scottE]

>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

  that would be a bad feature

Please keep us updated !

[fireonshakedwnstreet]

Damn. I wonder when it was kicking in?

[grawk]

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.

[DavidPuddy]

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.

[doomed]

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)
===================
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.
===================
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.

===================
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.

[fireonshakedwnstreet]

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?

[doomed]

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.

[doomed]

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.

[doomed]

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.