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I believe they are going to fix this in firmware so it just works.Excellent results! I hope this issue is made aware to and the instructions are available/accessible for all consumers as well
I believe they are going to fix this in firmware so it just works.Excellent results! I hope this issue is made aware to and the instructions are available/accessible for all consumers as well
I am thinking of getting one of these for DAC and amplifier measurements, can anyone think of a sub-$1K ADC that would be better performing for that purpose than this?
Michael
Nice loopback performance. Motu M4 can only achieve around -103dB THD+N. Can you repeat measurement and screen capture with dBc instead of dBV?Ended up impulse buying one of these as I figured even if it was only a small improvement over the MOTU M4 in terms of measurements the 10 channels of output + master volume control + SPDIF/TOSLINK inputs were enough to justify the purchase.
Overall pretty pleased with it despite a few quirks. I am a mac user and I first tried to use the interface without installing any additional software, in this configuration all outputs are set to -20 dB but you have no indication of this until you install the MOTU software! The level indicators will show full output but if you measure the output voltage you are only getting 0.86 V which is 10X less than the full output voltage of 8.6 V. Once I installed the MOTU software I was able to adjust this up to 0 dB.
From a measurement perspective at full output of 8.6V I found that using the back panel line inputs was best, here is a loop back at full output voltage from output channel 3 to line input channel 4.
View attachment 140223
For lower voltages I found that using the front panel microphone inputs was best, especially if the -20 dB pad was used with mic gain. Here is 2 V output with the -20 dB pad and +12 dB mic gain, output channel 3 to microphone input 2 (TRS to XLR).
View attachment 140224
Here is 4 V output with -20 dB pad and +6 dB mic gain, output channel 3 to microphone input 2 (TRS to XLR).
View attachment 140225
I also found that at least on my unit output channels 1-6 seem to perform a bit better than channels 7-10.
Michael
Nice loopback performance. Motu M4 can only achieve around -103dB THD+N. Can you repeat measurement and screen capture with dBc instead of dBV?
That seems largely unnecessary. According to Julian Krause (video posted a few posts up from yours), EIN is well in the green as-is, at -129.8 dBu(A) (150 ohm). As he says, you realistically have little over 1 dB to gain at best, plus you've got oodles of voltage gain available to begin with. Oh, and according to its specs, the DM1 actually has higher EIN (about -126.7 dBu(A) if you do the math).In this case would you still recommend the use of a mic activator (like the Se Electronics DM1 Dynamite, for instance) to boost the signal level for mics which do not require phantom power?
agreed, a mic activator is not necessary for this thing. Now, if you are interested in boutique preamps to *add* color, that's another story.That seems largely unnecessary. According to Julian Krause (video posted a few posts up from yours), EIN is well in the green as-is, at -129.8 dBu(A) (150 ohm). As he says, you realistically have little over 1 dB to gain at best, plus you've got oodles of voltage gain available to begin with. Oh, and according to its specs, the DM1 actually has higher EIN (about -126.7 dBu(A) if you do the math).
I might reconsider if you ever find yourself with a mic of less than 150 ohms worth of nominal impedance, but then you still need to select your mic activator carefully.
People have been doing some investigation of the innards if you know what to look for, including some tweaks (though instead of banishing the mains transformer from the device, I would rather have investigated what it's coupling into, either it's electrostatic and some shielding would be required or it's magnetic and there's a ground loop going on in the signal path or grounding scheme somewhere... I won't be surprised if it's not exactly AES48 compliant yet either).I would love to see how the 828mk1 measures. There was a lot of great music recorded with one of those (particularly electronic music where super quiet preamps aren't necessary).
I always test with generic class driver. The only exception is these pro interfaces where it is the norm to install their package to get the control software. Once there, I use their ASIO interface as well as otherwise people may question the results.@amirm, now that I think of it, it'd be nice for DAC tests to include a basic test with the generic UAC driver (UAC2 for Win 10, I think), to know about portability.
Instrument input is high-z input. So basically it's designed for high impedance source. Thus it means the noise from the source is dominant noise.Can an anyone please measure an RMS noise of an instrument input?
Would be interesting to know how it's compared to -116db of an rme babyface instrument input
Thanks.
Much appreciated
Depends on the pickups actually, also an audio interface noise floor can affect sound if using high gain apm sims.Instrument input is high-z input. So basically it's designed for high impedance source. Thus it means the noise from the source is dominant noise.
Only thing that matters is the immunity to interference. But normally the source is more vulnerable to interference like a guitar pickup.
As long it's good enough. I have tested several interfaces. There are horrible ones, eg low end m-audio. But once competent enough, there's little difference. Focusrite has been quite good imo so has RME and MOTU.Depends on the pickups actually, also an audio interface noise floor can affect sound if using high gain apm sims.
Anyway would be good to know.
Thanks
I know that MOTU has a bad reputation when it comes to linux support but I was able to set up a simple CamillaDSP configuration on a RPi 4 running Ubuntu server (5.11.0-1012-raspi kernel) for the ultralite mk5 and it was plug and play. Camilla recognized 18 channels of output and I was able to set up a simple 10 channel output configuration with no issues.
Will need to experiment more with the other inputs / outputs some more to make sure everything else works. Would really like to be able to setup a configuration with a TOSLINK or SPDIF input -> CamillaDSP -> 10 channel output.
Michael
Man, if the mk5 had remote volume control this RPi 4 + mk5 setup would be an absolute miniDSP killer. Way more flexible processing power and way better analog performance than something like a 4X10HD.
I use CamillaDSP's volume control, applied at the beginning of my pipeline. With 64-bit float computation and a 32-bit signal path, this should be as good as any volume control. Dither could also be applied at the end of the pipeline (going from 64-bit to 32-bit).
I use a FLIRC USB IR-receiver dongle on the Pi for the remote and a 7" LCD (non-touch) to display the volume level with a little Python script that communicates with CamillaDSP via websocket. So far I just have volume and mute working.
One thing I haven't investigated yet is whether the analog inputs (on the M4 in my case) can be routed thru CamillaDSP.