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Author Topic: miniDSP AmbiMIK-1 Ambisonic Mic  (Read 2652 times)

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Offline MIQ

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miniDSP AmbiMIK-1 Ambisonic Mic
« on: May 09, 2020, 04:45:34 PM »
I saw this new ambi mic from miniDSP this week.  Wondered if anyone else was checking it out?  Connects directly via USB cable.  https://www.minidsp.com/products/acoustic-measurement/ambimik-1  It looks neat.

127dBSPL Max

DIRAC software for conversions.  B format or Binaural outputs.

VST plugin with unique calibration.



Offline IronFilm

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #1 on: June 23, 2020, 10:43:10 AM »
That was an emotional rollercoaster:

EXCITEMENT! "This is a very affordable ambisonics mic"

disappointment.... "oh dear, it is a USB mic"

Offline Gutbucket

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #2 on: June 23, 2020, 12:01:59 PM »
Wondering if it can be used directly into a phone..
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Offline WiFiJeff

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #3 on: June 23, 2020, 01:09:04 PM »
Wondering if it can be used directly into a phone..

From the specs:

USB Audio   
Linux/OSx/Android Driverless

ASIO compatible driver for Windows

iOS support with USB camera adaptor  (This is how the output of the new Sonosax M2D2 goes into an iPhone.  But what recorder app will do 4 channel 32 bit up to 192 kHz??)

However the VST plugin that controls it is only Windows/Mac.

??

Offline MIQ

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #4 on: June 24, 2020, 09:54:51 PM »

But what recorder app will do 4 channel 32 bit up to 192 kHz??)


Auria will do 24/96 multi-channel on the iPad but I don't know if it will recognize the AmbiMIK-1. 

I still don't see much multi-channel audio (beyond stereo) on the iPhone yet.  The Mofonix app I use for in ear monitor mixing will create multi-channel mixes on the iPhone but its tight if you are looking at more than one mix.  Looks better on an iPad.  Doesn't record yet.

https://mofonix.com/mofonix-app.html
« Last Edit: June 24, 2020, 10:00:16 PM by MIQ »

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #5 on: June 24, 2020, 11:07:07 PM »
its really difficult to do more than a few channels on ios lightning connector due to bus power limitations
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Offline MIQ

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #6 on: June 25, 2020, 12:13:05 AM »
its really difficult to do more than a few channels on ios lightning connector due to bus power limitations

I don't think Core Audio (the audio engine in Apple products) has any channel limitations for the lightning connector and the processors in most phones these days are plenty powerful to do many channels of audio.  If you get the $40 Apple camera connection kit with the charger port, buss power is not an issue at all.  I run 24 channels in, 24 out, with my Motu Ultralight Mk4 connected to an iPad or iPhone running the Mofonix App almost every day without any issues.  The buss powers the iPad, the Motu plugs into the wall.  You could power the iPad with a USB battery supply connected to the camera kit if you really wanted to, but you still need to plug the Motu into the wall or find another way to power it. 
« Last Edit: June 25, 2020, 12:21:00 AM by MIQ »

Offline jerryfreak

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #7 on: June 25, 2020, 12:18:22 AM »
that motu doesnt look bus-powered to me. theres a 15V DC jack on the back
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Offline MIQ

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #8 on: June 25, 2020, 12:23:32 AM »
Yes I noted that, but that's how the device is powered.  I can't change that.  It's not the lightning connector that reduces the channel count is my point.  If you want to be battery powered with multi-channel audio on an iOS device you can do it.  It's not the lightning connector holding it back.

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #9 on: June 25, 2020, 12:35:23 AM »
Yes I noted that, but that's how the device is powered.  I can't change that.  It's not the lightning connector that reduces the channel count is my point.  If you want to be battery powered with multi-channel audio on an iOS device you can do it.  It's not the lightning connector holding it back.

again, bus power was the only limitation that i mentioned. im not aware of any 4 channel bus-powered devices

there are numerous devices like the motu that dont require bus power and work with OS
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Offline MIQ

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #10 on: June 25, 2020, 01:00:01 AM »
Sure, using the USB buss as a power source for the audio interface is not going to take you very far.  Are you expecting the iPhone or iPad to power your multi-channel interface? 

My point is that enabling multi-channel data on the lightning connector doesn't have anything to do with the buss power limitations.  As you noted, powering a multi-channel device with P48, a bunch of LEDs etc from USB power using the same lightning connector is not possible since it can't support that kind of power draw.

Motu Microbook II is 4 channel in "bus powered" but I think you still have to plug it into another USB port to give it enough power.  https://motu.com/products/motuaudio/microbook


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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #11 on: June 25, 2020, 01:15:25 AM »
Sure, using the USB buss as a power source for the audio interface is not going to take you very far.  Are you expecting the iPhone or iPad to power your multi-channel interface? 

no, hence the post. I'm quite impressed that it can power 2 condenser mics a gain stage, and an ADC like with the d:vice, but thats nearing the limit of the power available
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Offline MIQ

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #12 on: June 25, 2020, 01:31:24 AM »
Yea d:vice is really neat.  I wish I could afford one.  ;D  This thread’s Ambi Mic with built in electrets and a2ds integrated inside the mic may have a chance of being buss powered like the d:vice. 

Offline Len Moskowitz (Core Sound)

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #13 on: July 13, 2020, 10:50:09 AM »
It's a first-order, generically calibrated microphone. For $349.

With a bit of luck, as a microphone it'll perform slightly better than the Zoom H3-VR recorder, but without the integral recorder. The Zoom retails for $249.
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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #14 on: July 13, 2020, 01:52:22 PM »
Len,

When you write "generically calibrated mic", what does that mean?

Offline Len Moskowitz (Core Sound)

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #15 on: July 14, 2020, 11:15:40 AM »
"Generically calibrated" is the opposite of "individually calibrated."

Ambisonic microphones work on principles that depend on the very small differences between their capsules, plus a bunch of other factors. In this case and for the Zoom H3-VR, just because a microphone has four capsules mounted on a tetrahedral mount, that doesn't mean that it will work well.

It turns out that every microphone capsule is different. They might all meet the manufacturer's specifications, but those specifications have ranges of variation, and those variations are incredibly important for ambisonic microphones.

There are also other sources for variations in addition to the capsules.

Calibration is the process that measures the variations and provides corrections for them.

Because it takes time and equipment and manpower to test each of the capsules and then match them into sets, and because it costs money to test each assembled ambisonic microphone to develop correction files for each complete microphone, the manufacturers compromise. They make the assumption that all of their capsules are sufficiently matched, and all of their assembled microphones are sufficiently identical to use a single generic calibration correction.

From the beginning the assumptions are wrong. And as the microphones age, the assumptions get even worse. You're still stuck with the original generic calibration.

That's why each ambisonic microphone needs to be individually calibrated, and supplied with its own correction file. And as it ages, it will need to be re-calibrated.

Ideally, each set of capsules should be matched for a bunch of specifications - not just frequency response and/or sensitivity. And then when they're assembled into the microphone mount, each microphone should be measured so that its performance can be corrected with an individual calibration file.

All Core Sound OctoMics and TetraMics are individually calibrated. We recommend re-calibration every two to three years, depending on application. We offer a recalibration service for our microphones.

(We also offer an initial calibration service for other manufacturers' ambisonic microphones, including those from Rode, Sennheiser and the old Soundfield.)



« Last Edit: July 14, 2020, 12:46:03 PM by Len Moskowitz (Core Sound) »
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Offline MIQ

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #16 on: July 14, 2020, 12:34:58 PM »
Hi Len,

I appreciate you taking the time to explain that.  When they state that they worked to create a "VST plugin specifically calibrated for the ambiMIK-1 with over 1200 measurements", they are talking about taking measurements of the mics in development and applying those measurements/calibrations to all the mics they produce, regardless of the slight differences in the individual capsules actually being assembled. 

I've read a fair bit about mic calibration, even the old Soundfield design (I'm a big fan of Gerzon), and can see how the costs could quickly get out of hand for a budget minded product.  As usual, the more accurate you get, the more time and money it takes. 

Offline Len Moskowitz (Core Sound)

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #17 on: July 14, 2020, 12:39:57 PM »
When they state that they worked to create a "VST plugin specifically calibrated for the ambiMIK-1 with over 1200 measurements", they are talking about taking measurements of the mics in development and applying those measurements/calibrations to all the mics they produce, regardless of the slight differences in the individual capsules actually being assembled. 

Yes. And the variations in mounting the capsules in the capsule mount. And the effects of the cables behind the capsules on the venting of the capsules. And others.

Some of the "slight differences in the individual capsules" are not slight. Some are quite large and significant.
« Last Edit: July 14, 2020, 12:45:18 PM by Len Moskowitz (Core Sound) »
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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #18 on: July 14, 2020, 12:50:56 PM »
Len, how do you know for certain whether or to what extent other manufacturers calibrate the capsules for their ambisonic mics?  Or what those manufactures' internal specs are for the capsules they use in their ambisonic mics?
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Offline Len Moskowitz (Core Sound)

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #19 on: July 14, 2020, 01:05:18 PM »
Len, how do you know for certain whether or to what extent other manufacturers calibrate the capsules for their ambisonic mics?  Or what those manufactures' internal specs are for the capsules they use in their ambisonic mics?

We buy their mics and test them. As they do for ours.

We know that all the manufacturers match their capsules. Some do a better job than others. Some clearly don't test other important specifications. None of them calibrate completely assembled microphones, except perhaps one, and we think that they don't do a very good job. Almost all use a generic calibration.

In one case a generic calibration is warranted because they use MEMS elements as capsules; they are reliably long-term stable. They're noisy though.

The rest of the manufacturers use standard electret capsules. No matter how tightly matched they are during manufacture, two years (or less) downstream they've drifted.

One microphone manufacturer provides individual calibrations that correct for sensitivity variations only. They buy their capsules (they don't manufacture them) and presumably decided that correcting errors is less expensive than sorting for tightly matched capsules. They don't provide individual calibrations for the assembled microphones.

If you really want to know how good an ambisonic microphone is, look at its decoded polar directivity patterns - for example on a tetrahedral first-order microphone, look at the B-format's omni and the figure-8 channels . If they don't publish them, ask them why.

If they publish a frequency response specification, does it provide tolerances? If not, it's not real - it's a marketing specification. (Individual calibration allows for roughly two more octaves of bass.)

« Last Edit: July 14, 2020, 07:38:47 PM by Len Moskowitz (Core Sound) »
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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #20 on: August 23, 2020, 03:33:34 PM »
disappointment.... "oh dear, it is a USB mic"

Is there something generally wrong with USB mics?

@all others:

Couldn't we simply agree that it isn't as good as microphones made by Core Sound, because obviously nothing could ever be, and carry on with discussing the AmbiMIK-1?

Not everybody needs a Ferrari to drive to work. Not even everybody wo could afford one, let alone the rest of us.

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Offline MIQ

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #21 on: August 23, 2020, 10:53:02 PM »
Ralph I don't think there is anything "wrong" with USB mics.  I imagine most of the tapers here are not interested in using them because the makers of these mics usually make compromises in performance that tapers are not interested in living with.  Max SPL, polar response, self noise are compromised in many of these mics to reach a price point.  They are not aspirational mics that most people dream of owning someday.  With that said, I think they will continue to get better and the cost/performance trade-offs will not be so severe.  Len's mics cost more because he is striving for better performance at a slightly higher price point.  I wouldn't say Len's mics are at Ferrari price points.  It still costs a certain amount of money to make a quality product at low volume. 

The Senn Ambeo is $1300  https://www.sweetwater.com/store/detail/AMBEO--sennheiser-ambeo-vr-microphone?mrkgadid=3341927511&mrkgcl=28&mrkgen=gpla&mrkgbflag=0&mrkgcat=studio&recording=&acctid=21700000001645388&dskeywordid=92700046934908799&lid=92700046934908799&ds_s_kwgid=58700005285215127&ds_s_inventory_feed_id=97700000007215323&dsproductgroupid=744089619784&product_id=AMBEO&prodctry=US&prodlang=en&channel=online&storeid=&device=c&network=g&matchtype=&locationid=9030049&creative=353564234315&targetid=aud-374460618936%3Apla-744089619784&campaignid=2005216453&gclid=Cj0KCQjwp4j6BRCRARIsAGq4yMGHS2fgU0PoxqvxdcWzFwUZk5Z7rxDrfNSyOXYmGMyRIFDt1FbBgaYaAj-vEALw_wcB&gclsrc=aw.ds


The Rode NT-SF1 is $1000
https://www.americanmusical.com/rode-nt-sf1-soundfield-true-condenser-ambisonic-mic-kit/p/ROD-NTSF1?src=Y0802G00SRCHCAPN&adpos=&scid=scplpROD+NTSF1&sc_intid=ROD+NTSF1&gclid=Cj0KCQjwp4j6BRCRARIsAGq4yMHhSpNHZ7EvDorOYe2-uGTa46pgUu_fM_VIkgu9r15_fObgO4yE-dAaAqAjEALw_wcB

The Core Sound Tetra is $825
https://www.core-sound.com/TetraMic/12.php

The mini DSP mic is $325
https://www.minidsp.com/products/acoustic-measurement/ambimik-1

Seems like there's room for a few manufacturers at different price points.  Get what you can afford and start using it.  Just don't expect them to all have the same performance.  Is there something else you want to know about the miniDSP?  I think it looks cool for an affordable ambi mic.  I also really like the DIRAC guys from working with them in the past, so I posted it here.  I bet it works well, but I've never played with one.  If no one wants to buy it yet, not even me, I guess we don't have much to say.
« Last Edit: August 24, 2020, 02:28:28 AM by MIQ »

Offline fotoralf.be

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #22 on: August 24, 2020, 06:07:44 AM »
I don't see why a microphone with a digital output is necessarily of inferior quality. BOM wise, there shouldn't be much difference between four good quality analog output stages and a decent ADC with four channels. Incorporating the necessary correction for an ambisonic array in a digital output configuration should be easier and more predictable than having the signal go through the user's analog preamps and ADCs of unknown make, specs and quality and then doing the correction in the computer after goddess knows what's happened on the way there.

Yes, most USB microphones currently on the market are low-end products but there is no rule saying they need to be. Certainly not from the technical side.

Having said this, I think there should be a future digital interface other than USB allowing a synchronised connection of several digital microphones without timing problems. Not so much a problem with an ambisonic mic that will mostly be used on its own.

BTW the price here in Europe is around 650 USD. The usual margin of 3 percent our importers scrape their meagre living from...

Ralf
« Last Edit: August 24, 2020, 10:05:37 AM by fotoralf.be »
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Offline DSatz

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #23 on: August 24, 2020, 01:11:02 PM »
Until/unless I become aware of a reason to think otherwise, basically I consider USB mikes to be fine for podcasting, on-line meetings and casual tracking, but nothing more. I'm probably biased from the early days of USB (1.0 and 1.1), but I simply don't trust a USB connection to handle (say) 24-bit two-channel audio at 48 kHz without ever dropping any samples. To the best of my knowledge, the basic scheme of the interface has no provision for guaranteeing any particular, required level of availability, bandwidth and buffering to a given peripheral.

I assume that newer versions with higher maximum data rates are "better" in that one has better luck with them in general--but I simply don't know for a fact that my signals will get through to the computer (or whatever) unchanged, so I don't consider USB a suitable type of interface for serious recording.

Again, subject to my finding out that things have changed fundamentally ...

« Last Edit: August 24, 2020, 01:12:53 PM by DSatz »
music > microphones > a recorder of some sort

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #24 on: August 24, 2020, 01:30:54 PM »
...but I simply don't trust a USB connection to handle (say) 24-bit two-channel audio at 48 kHz without ever dropping any samples.

You mean all those USB computer audio interfaces delivering multiple channels at 48 kHz/24 bit  and some even at higher rates all don't work correctly? Or is this a special phenomenon that only occurs with USB microphones?

What kind of digital connection would you recommend for transferring the digitised audio from analog microphones into a computer?

Ralf 
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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #25 on: August 24, 2020, 08:46:15 PM »
DSatz,

I am with you for USB microphones, which are often inexpensive and have who-knows-what for ADCs in there.  The majority of them still max out at 16/48, though there are a few that do better nowadays.

As far as USB being a reliable interface for recording, I think the newer spec versions of USB are totally reliable.  The new MOTU M2 interface I currently use uses USB 3.1 type C, and it has been nothing but rock-solid for me.  As long as you are on at least USB 2.0, you have plenty of room for multichannel, high-bitrate recording.  Look at some of the video reviews from Julian Krause for some good technical analyses of these newer interfaces.

There are many high-quality USB interfaces out there that are using the newer specs.  If the 10 gb/s of USB 3.1 gen2 isn't enough for you, there is Thunderbolt 3, which will do 40 gb/s but your selection will become smaller.

There's MADI and Dante, but those are really overkill unless you have very high track counts or need to go long distances.
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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #26 on: August 24, 2020, 09:33:27 PM »
There's not a locking USB connector, is there? 
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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #27 on: August 24, 2020, 10:37:33 PM »
Until/unless I become aware of a reason to think otherwise, basically I consider USB mikes to be fine for podcasting, on-line meetings and casual tracking, but nothing more. I'm probably biased from the early days of USB (1.0 and 1.1), but I simply don't trust a USB connection to handle (say) 24-bit two-channel audio at 48 kHz without ever dropping any samples. To the best of my knowledge, the basic scheme of the interface has no provision for guaranteeing any particular, required level of availability, bandwidth and buffering to a given peripheral.

I assume that newer versions with higher maximum data rates are "better" in that one has better luck with them in general--but I simply don't know for a fact that my signals will get through to the computer (or whatever) unchanged, so I don't consider USB a suitable type of interface for serious recording.

Again, subject to my finding out that things have changed fundamentally ...

I'm pretty sure even the old USB standards are capable of bit perfect audio.  Check this out: https://thewelltemperedcomputer.com/Intro/SQ/USB_SPDIF.htm
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Offline fotoralf.be

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #28 on: August 25, 2020, 04:04:38 AM »
There's not a locking USB connector, is there?

Not on this microphone from the look of it but Neutrik make several versions:

https://www.neutrik.com/en/search?q=usb

Ralf
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Offline WiFiJeff

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #29 on: August 25, 2020, 11:21:16 AM »
I was playing around with the Zylia ZM-1 for about a year prior to the Covid lockdown.  This is a 3rd order ambisonic mic using MEMS capsules, 19 channels at 24 bit/48 kHz, over USB to a pocket computer (or more recently a dedicated ZR-1 recorder).  Most of the mixing I was doing was only first order, comparing it to my Josephson C700S which is basically a native B format first order mic without the Z channel (as long as the orchestra isn't throwing violins over your head this is fine, for me).  I did use Reaper with the Zylia Studio Pro plugin to produce "virtual" directional mics, a very neat trick. The next generation of MEMS mics may make this a killer app, for now the C700S is the serious mic.  But the ability of USB to handle 19 channels of 24/48 has not been an issue that I have found.

Jeff

Offline DSatz

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #30 on: August 29, 2020, 08:44:19 AM »
My posting above was based mainly on what I learned at an AES presentation about USB for professional audio, back when USB was around the 1.1 version level. It wasn't highly regarded for professional audio at that point, but not mainly because of bandwidth per se. Even then the bandwidth was sufficient for some applications. But that sufficiency was based on uninterrupted good conditions--mainly, on not using the same computer for anything else or putting any other peripherals on the same USB bus (sorry, that's redundant the way "ATM machine" is redundant).

The USB protocol for host devices had no provisions for catering to peripherals with a specific throughput that MUST be available under all conditions, e.g. even if the host computer is unusually busy, or if other peripheral devices on the same bus also raise high demands. USB was designed to handle as much data as it could, given the demands from all attached devices and the availability of CPU cycles and memory from its host device (PC or whatever). It was designed to "fail gracefully" when those demands exceeded the available bandwidth, so that if circumstances didn't allow it to convey certain information, it would carry on without locking up or requiring user intervention. To put it another way, it was designed to conceal its failures rather than communicate them.

For a number of years most high-quality professional audio equipment that was designed for connection to PCs used proprietary option cards that plugged in to the host computer's motherboard. That was expensive and required a lot of extra development time, not to mention the inconvenience of opening one's computer to plug the card in (and the fact that laptops were thus ruled out). Clearly USB, FireWire and other similar protocols would be preferable if/when they were up to the task. There was enormous market pressure to switch over to them, ready or not.

Fast forward to today; I've got ~15 USB 2.x or 3.x devices attached to my PC, many via two outboard "hubs". There are at least four independent host devices on the motherboard of this computer. So each hub is subject to contention among the devices attached to it, over which I have no control nor even any way of monitoring; each bus is subject to contention among the devices attached to it, over which I have no control nor even any way of monitoring, and each host device on the motherboard, likewise. The Windows device manager doesn't identify these peripherals in a useful way nor show the overall layout of hosts vs. peripherals to let me balance the loads among the available buses. Maybe I have always had 20 times more available bandwidth as I have ever needed; maybe internal buffering on the peripheral side is always enough to get through the rough spots that I happen to have; maybe on a good day everything has sufficient margin, but during certain tasks it doesn't. I couldn't tell you, because the system is designed to keep on functioning at a reduced level of performance rather than complain. And reduced performance in this case means ignoring a peripheral that is asking for attention that can't be granted at that moment.

Some of the devices that I attach via USB include disk drives. When copying files to and from them, the equipment and the operating system obviously follow strategies to make sure that bytes aren't dropped. But as users we can see that the data transfer speed is allowed to vary during such operations. When writing large numbers of small files to a drive, for example (especially a spindle drive rather than an SSD), everything slows way, way down as it must.

Now maybe in the meantime the USB standard has been developed in exactly the needed direction, so that a bus will configure itself when a certain class of peripheral device is attached, pre-allocating host resources on a basis that guarantees uninterrupted, error-free isochronous data transfer. There are apparently some elements of that in effect nowadays--but what do they add up to in practice with typical, current implementations, or with the arrangement that I have on my PC today? I don't happen to know the answer to that, other than "all the other kids are doing it, so it must be OK." And I'm just pointing out that yeah, maybe--but it's really strange not to know or even to have any way of knowing.

--best regards
« Last Edit: August 29, 2020, 08:57:21 AM by DSatz »
music > microphones > a recorder of some sort

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #31 on: August 29, 2020, 08:54:59 AM »
I've got ~15 USB 2.x or 3.x devices attached to my PC, many via two outboard "hubs".

And this is the computer you carry along for your recordings?

Ralf
Photography and industrial audioscapes from Western Europe. - Sound examples: http://aporee.org/maps/projects/fotoralf - Blog (German): http://the-real-fotoralf.blogspot.com

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #32 on: August 29, 2020, 09:03:30 AM »
Hi, Ralf. I stopped using a laptop for location recording about 15 years ago. At the time I was using a PCMCIA card that accepted 16-bit 44.1 kHz S/P-DIF input. It seemed to work, at least the way that I was using it. I was taken aback when very suddenly the PCMCIA (or "PC Card") interface was dropped by the industry like a hot potato.

But your question underlines the point--you wouldn't (in your right mind) attach any unnecessary peripherals to a computer that you want to use for recording, nor run any other programs at the same time, etc., because PCs (and Macs) aren't designed for "privileged" real-time data input.

--best regards
« Last Edit: August 29, 2020, 09:05:14 AM by DSatz »
music > microphones > a recorder of some sort

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #33 on: August 29, 2020, 09:19:24 AM »
Hi, Ralf. I stopped using a laptop for location recording about 15 years ago. At the time I was using a PCMCIA card that accepted 16-bit 44.1 kHz S/P-DIF input. It seemed to work, at least the way that I was using it.

Around ten years ago, I've used a EMU 1616M audio interface connected via a PCI Express card to what was then a top-of-the line laptop and that was the first and last time I've had hickups and dropouts while recording. 

Since, I've been using various USB and Firewire audio interfaces and never experienced any problems of the kind you appear to be afraid of. 

Looking at the bandwidths of USB 2, 3, and C as well as Firewire, Thunderbolt, and whatever might be next week's dernier cri, a 'privileged' real-time input just isn't a topic anymore.   

Ralf
Photography and industrial audioscapes from Western Europe. - Sound examples: http://aporee.org/maps/projects/fotoralf - Blog (German): http://the-real-fotoralf.blogspot.com

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #34 on: August 29, 2020, 03:10:00 PM »
The reason I have been playing around with the dedicated new ZR-1 recorder (which connects to the 19 channel ZM-1 mic also by USB connection) is that the dedicated Windows 10 micro-computer I was using, the Ockel Sirius A Pro, is fanless and deals with excess heat by slowing down processing speed.  Usually this has not been a problem, but once or twice it seems to have been the root of a recording error.  The slightly larger Chuwi Microbook I tried has a fan which is a bit too noisy.  Using a bigger, more capable, laptop is no advantage over the dedicated recorder for portability.  My problems do not seem in any way USB related, as far as I can tell.

Jeff

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #35 on: August 29, 2020, 03:13:32 PM »
Throughput rates, as I said, aren't my main concern; clearly those have gone through the roof, compared to the early days. It's the fact that the host isn't obliged to pay any attention whatsoever to a given peripheral in a given interval of time, if the load on the host during that interval is too severe for whatever reason.

As far as I can see (though admittedly I didn't dig deep--and deep in this case would be very deep), the facility for isochronous transfer in USB is on a strictly frame-by-frame basis. In other words the system can't drop bytes within frames, but entire frames can be dropped unless there's some additional protocol in place to cache and resend them if they're not received. Any mechanisms for guaranteed delivery of data, or clear indications of when that delivery fails, are completely foreign to the USB protocol.

I'm not arguing against the use of USB peripherals for audio; I'm just saying that I've always been wary of them. The development of such devices came from the consumer side, and there was a memorable period of configuration and performance headaches with such devices, which soured me on them. And I'm unaware of any fundamental change whereby a certain line was crossed, and now we can tell for sure that things are working 100% OK. I prefer protocols and connection methods that are designed from the start to work with a professional level of reliability, rather than being designed to try and get by without their failures being noticed--even though I'm sure they've become "probably OK to use" due to the gradual increase in host speed over the years, i.e. Moore's Law.

Admittedly I am an old curmudgeon (and was already a curmudgeon when I was younger; it's awkward being a teenage curmudgeon, let me tell you!), and I have a big resentment about the number of different, incompatible USB plugs, adapters and cables that I have to keep around--which I realize is the result of the the USB standards group's sincere best efforts. To say more would be to launch into a general criticism of the times we live in ...
« Last Edit: August 29, 2020, 03:25:14 PM by DSatz »
music > microphones > a recorder of some sort

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #36 on: August 29, 2020, 03:25:09 PM »
Then by all means stay away from recording with computers in general and especially under Windoze.

Ralf
Photography and industrial audioscapes from Western Europe. - Sound examples: http://aporee.org/maps/projects/fotoralf - Blog (German): http://the-real-fotoralf.blogspot.com

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #37 on: August 29, 2020, 03:41:12 PM »
Ralf, I know that you're mocking me to some extent, but I'll cheerfully go along with it. I never record directly to a computer via USB for exactly the reason I've given in this thread.

I realize that I left out a total horror show example of an experience I had that is directly "on point"--a completely ruined three-track recording session (to a laptop computer via a four-channel USB interface--"Quattro Pro" from Midiman / M Audio) that I didn't realize was ruined until I got home and tried to edit the files. There were increasingly large blocks of skipped samples after the first ~20 minutes or so of each file. I'd put that experience out of my mind, I guess. Nothing beyond those first ~20 minutes was retrievable. It was the worst technical failure in my fifty years of recording, unless I'm forgetting something else.

And OK, if there had to be a 20-minute limitation, if I'd known about it I could have worked within it. It would have been extremely awkward and frustrating, but the entire session wouldn't have been lost.  I had tested the equipment beforehand, of course, but it never occurred to me that there might be an increasing problem with longer takes, so my testing was limited to samples of a minute or two.

I'm currently in the midst of a huge archiving project, but all the real-time audio work takes place on audio equipment, ending up with a digital audio recorder that is nothing more and does nothing more. Then the stored result is physically moved over to a computer for final editing and processing. That makes the most sense to me--even if it's 99.x% sure that it would be OK to record directly to the computer and save the physical transfer of the stored files.

Also, I'm perfectly well aware that inside some of my recording equipment, microprocessors are doing digital signal processing. But they are designed so that the number of samples out = the number of samples in, with no wishing, hoping or begging involved.

--best regards
« Last Edit: August 29, 2020, 09:47:13 PM by DSatz »
music > microphones > a recorder of some sort

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #38 on: August 29, 2020, 03:50:53 PM »
If this saves your peace of mind then you're certainly welcome to it. And I'm being totally serious here.

Ralf
Photography and industrial audioscapes from Western Europe. - Sound examples: http://aporee.org/maps/projects/fotoralf - Blog (German): http://the-real-fotoralf.blogspot.com

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #39 on: August 30, 2020, 12:49:27 AM »
I too prefer "standalone" recorders.
If you don't mind running off AC power, the Behringer XR series of mixers works very well.
You can do a full mix, and also record either stereo or multi track.  Control remotely using a phone, iPad or laptop computer.
I too have played with laptops but always rely on standalone devices.  The last thing I need is boot or update problems at a live gig.
  Richard

Please DO NOT mail me with tech questions.  I will try to answer in the forums when I get a chance.  Thanks.

Sample recordings at: http://www.soundmann.com.

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #40 on: August 30, 2020, 08:11:14 AM »
The reason I have been playing around with the dedicated new ZR-1 recorder (which connects to the 19 channel ZM-1 mic also by USB connection) is that the dedicated Windows 10 micro-computer I was using, the Ockel Sirius A Pro, is fanless and deals with excess heat by slowing down processing speed.  Usually this has not been a problem, but once or twice it seems to have been the root of a recording error.  The slightly larger Chuwi Microbook I tried has a fan which is a bit too noisy.  Using a bigger, more capable, laptop is no advantage over the dedicated recorder for portability.  My problems do not seem in any way USB related, as far as I can tell.

Jeff

IMHO, you need to get away from systems like that if you want quiet paired with solid performance.

I have been a quiet PC building enthusiast for many years now, back when it was relatively difficult to do so.  Now, you can make yourself something that is vanishingly quiet until it is under heavy load.  You start with a quality case that has thick, well-damped panels, and add large, low-RPM fans.  Then it's a matter of using a large CPU cooler with a large fan, and you can then set all of your power-saving settings in Windows to "high performance".

Here is my current system.  The video card fans and PSU fan stay off until there is heavy load, and the system and CPU fans are extremely quiet, staying under 500 RPM at low load.

FYI, I do NOT recommend liquid cooling.  Besides all of the hassle with those setups, they often require more fans than air cooling in order to get good flow through the radiator.  More importantly, the best air CPU coolers (Scythe, Noctua, etc.) actually outperform most liquid setups now.
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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #41 on: August 30, 2020, 08:52:34 AM »
I haven't been using Windows for the last two decades. Is there still the eternal fight for taming interrupts and the dark deamons in the underworld of the registry to get things running without hickups and conflicts?

Ralf
Photography and industrial audioscapes from Western Europe. - Sound examples: http://aporee.org/maps/projects/fotoralf - Blog (German): http://the-real-fotoralf.blogspot.com

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #42 on: August 30, 2020, 01:13:33 PM »
I haven't been using Windows for the last two decades. Is there still the eternal fight for taming interrupts and the dark deamons in the underworld of the registry to get things running without hickups and conflicts?

Ralf

Ha!  I remember those days.  I used to be a PC repair tech 20-25 years ago, and I had IRQ numbers and memory addresses memorized for common ports and hardware.

Thankfully, those days are long over.  No more manually resolving IRQ conflicts, and I rarely delve into the registry unless there is a very unique case.  Today, Windows "just works" for the most part, as the Mac ads used to say.  Actually, it tends to be a better choice than Mac for things like music production nowadays, as some of the most recent OSX updates have rendered some popular pro audio apps unusable, because of breaking the audio subsystem, removing 32-bit app capability, and such.

The biggest point against Windows 10 is that it is quite invasive of user privacy by default.  Fortunately, they have made it easier to disable most of that telemetry in recent versions.  I also run this on all of my systems to get rid of a lot of the pre-installed crap I don't use.
https://github.com/Sycnex/Windows10Debloater
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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #43 on: August 30, 2020, 04:06:29 PM »
Actually, it tends to be a better choice than Mac for things like music production nowadays, as some of the most recent OSX updates have rendered some popular pro audio apps unusable, because of breaking the audio subsystem, removing 32-bit app capability, and such.

*sigh*

I know. I'll be stuck with Mojave for years to come because I'm not ready to discard perfectly functioning hardware like my MOTU traveler Mk3.

Ralf
Photography and industrial audioscapes from Western Europe. - Sound examples: http://aporee.org/maps/projects/fotoralf - Blog (German): http://the-real-fotoralf.blogspot.com

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Re: miniDSP AmbiMIK-1 Ambisonic Mic
« Reply #44 on: August 30, 2020, 05:25:54 PM »
Actually, it tends to be a better choice than Mac for things like music production nowadays, as some of the most recent OSX updates have rendered some popular pro audio apps unusable, because of breaking the audio subsystem, removing 32-bit app capability, and such.

*sigh*

I know. I'll be stuck with Mojave for years to come because I'm not ready to discard perfectly functioning hardware like my MOTU traveler Mk3.

Ralf

It's really sad to see.  Apple used to be the platform for content creators.  Now it seems they no longer care about that segment of their user base.  The best way out from a customer standpoint would be if Apple stopped making desktops and laptops, and went 100% in on iOS devices.  Then, they could sell or license OSX to hardware companies who could build dedicated systems. 

Of course, this will never happen.
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