Can't seem to monitor on 2.3.0

Hi folks,

I’m trying to use Audacity to digitize some quad recordings. For input I am using a Behringer UMC404 four channel A/D D/A. Output is a Marantz AV7005 over HDMI with a GeForce GT 730 card.

I can play quad recordings from FLAC through the Marantz with FooBar.

I can connect to the UMC404 and see levels in the “VU” meters in Audacity, and I can play two channels of a four channel recording back through the Marantz from Audacity.

What I can’t figure out how to do is monitor through the Marantz while recording from the Behringer. Any ideas what I’m missing here? The Start Monitoring option if I right-click on the meter is greyed out.


OK. I found the software playthrough option. Unfortunately, if I enable this, I then get either invalid device, or invalid sample rate, when trying to record four channels with WASAPI. If I switch to Windows Direct, I can record two channels and monitor, but I need to record four channels…

Look in the Windows Sound Control Panel and check that both the recording and playback UMC404 devices are set to the same sample rate, and that it matches the “Project Rate” in Audacity (bottom left corner of the main Audacity window). Then try starting a new project (shut down Audacity and restart), and record with WASPI, and record and monitor via the UMC404.

Does that help?

Doesn’t help, I’m afraid.

It’s not even a question of changing sample rates, as the Marantz does support up to 192K, and it plays through just fine if I use Windows DirectSound.

I have gotten into a number of situations where Audacity is just doing Invalid Sample Rate for no apparent reason, and closing it and retrying the same steps works on the second or third try. It also locked up once, and another time acted like it had launched a modal dialog somewhere off screen, so I had to kill it.

For now, I’ll try to get by without monitoring. I can monitor the front two channels through the ADC with headphones, so that’s somewhat useful.

That did not help. I seem to having a couple of different types of problems, though, which usually result in either a sample rate error or a device open error. Closing and reopening Audacity and doing the same things often works.

One thing that might be exacerbating this is that my HDMI playback connection is to my AV prepro, which I also use for source of some recordings… not through HDMI, but when I switch the preamp to Phono to record from an LP, my HDMI connection goes away, since that’s no-longer the input the preamp is looking at.

I also had Audacity actually lock up on me a couple of times. Once completely frozen, and once where it acted like it had a modal dialog open but not accessible on either display. (Just a bonk sound whenever I tried to click anywhere in the app window).

I did manage to get a four channel album recorded… but ended up with some dropouts in one place about a third of the way in. I’ll have to do that track again. Monitoring for that wasn’t as much of an issue since the preamp was playing the record as well as routing it to the SQ decoder which was feeding the ADC. For other sources, though, I’ll probably just use the headphone monitor in the ADC itself.

OK, you’ve confused me :confused:

What is your set-up in detail? Fill in the gaps and correct me where I’m wrong…

  • You have a home built mini-tower computer.
  • It has an on-board Intel sound card that you don’t use.
  • You have a Behringer UMC404 connected via USB. You wish to use this for 4 channel recording.
  • When you say “preamp”, you are referring to the “Behringer UMC404”.
  • You have 4 XLR hydrophonic microphones which you are using to make a quadraphonic recording of being inside a fish tank.
  • You have a GeForce GT 730 video card with DVI-D, HDMI, and VGA outputs.
  • You have your main display monitor connected to the GeForce GT 730 via DVI-D, and a secondary display connected via VGA.
  • You have a Marantz AV7005 which is connected to the HDMI output of the GeForce GT 730.
  • You use the Marantz AV7005 as your audio output device, and would like to use it with 4 channel output but you can settle for 2 channel output as you know that Audacity does not support playing more than 2 channels.
  • When you say “AV prepro”, you are referring to the Marantz AV7005.
  • When you say “SQ decoder”, you are referring to the Marantz AV7005.
  • You want to record 4 channels simultaneously with Audacity, via the Behringer UMC404, while simultaneously monitoring what you are recording via the Marantz AV7005. You are aware that even if you get this to work, there will be these limitations:
  • Playback limited to 2 channels (stereo)
    • There will be a bit of delay between the signal going in, and the sound coming out because there is no hardware route between the input device and the output device
  • You are not concerned about hearing other tracks play while recording - you only want to record 4 tracks.
  • So far you have been unable to monitor the recording when recording from the Behringer UMC404 as input and the Marantz AV7005 as output.

I can’t figure out this sentence in which you use generic terms to refer to three pieces of hardware:
“Monitoring for that wasn’t as much of an issue since the preamp was playing the record as well as routing it to the SQ decoder which was feeding the ADC.”

What is the “preamp”?
What is the “SQ decoder”?
What is the “ADC”
How are the preamp, SQ decoder, ADC, and the computer connected together?

Thanks, that made me smile.

Yes, it’s a home-built mini tower that has an on-motherboard sound card that I’m not using (and that I have disabled in BIOS). Externally I have a Rocksmith USB guitar cable, which I’m not using for this activity, and the UMC404HD connected over USB.

I am not using any microphones. I am using the UMC404HD to be able to record four channels simultaneously.

SQ is a matrix encoding format used mainly for four channel (Quadraphonic) recordings on LP vinyl discs. It was relatively popular in the first half of the 1970s. Its phase encoding of rear channel sum and difference information allows it to present a two channel playback from the disc that is pretty similar to the stereo mix, so that SQ records can play on non-SQ systems.

To decode the other two channels, an SQ decoder is used. Mine is an external box - a Lafayette SQ-W.

The preamp is the Marantz AV7005. It supports 7.1 audio with HDMI video switching. When fed through digital inputs, its onboard DACs can handle up to 24/192 signals, and it provides delay, level control, bass management, and some amount of room correction EQ. It also has one set of 7.1 analog inputs, but these do not provide any signal processing other than volume control - they are just fed fairly directly to the outputs.

So, my setup is that the PC is connected to the preamp by HDMI. The preamp is connected to the TV by HDMI, which provides my main PC “monitor” when the preamp is set to the PC input. For the recording signal here, I have a turntable connected to the preamp, with the tape loop sending the analog stereo signal to the SQ-W decoder. The four-channel analog output from the decoder goes to the four inputs (at line level) of the UMC404HD. The PC then gets the USB output from the UMC.

Challenges I have with this:

  1. To record from an LP, I need to switch the preamp to Phono. At that point, HDMI video from the PC is no-longer being routed to the TV. Currently I have a separate 22" monitor connected to the PC so I can run Audacity on that when I can’t view the main monitor/TV. I’d rather duplicate the desktop directly to the TV over DMI, but the nVidia card doesn’t seem to support that.

  2. In some cases I want to record other four channel inputs, like from a Quad 8-track deck. This would be fed directly into the UMC404HD, so, to monitor it, I would want to be able to feed the signal (at least a stereo mix-down of it) back to the preamp from Audacity (over HDMI).

  3. (Probably related to 2) At some point, Windows Update replaced the Behringer UMC404HD driver with Microsoft’s own. Their’s doesn’t support higher sample rates and was locked to 44.1. I installed the newest Behringer driver manually, but that now provides 2X2 inputs for WASAPI instead of 1X4. I then went back to their older (3.29) driver, and got the 1X4 input back, but, for some reason, it will not save a change to sampling rate in Control Panel. Whatever I select, even if it’s just after a reboot, Windows complains that the device is in use, and then does not seem to save the setting… leaving me stuck with 24/44.1.

I am currently working on building Audacity with ASIO support, to see if that fixes my sample rate problem, and hopefully corrects at least #3, and maybe #2 as well.

This problem with the Behringer UMC404HD drivers was also reported here: Installing ASIO in Audacity
It looks like they realised that they had problems with the multi-channel WDM driver, so replaced it with 2x stereo drivers (just my guess).

Perhaps adding a “manual HDMI switch” would solve this problem. (Equivalent to unplugging the PC from the pre-amp and connecting it directly to the TV).
Signal route:
Record deck → Pre-amp → SQ-W → UMC404HD → PC