DRC Plugin


I need help about Volumio room correction DRC.

First, I would like to thank (in advance…) the developpers (@Balbuze): creating an inexpensive solution for room equalization using decoding capabilities of a Rasberry was just brilliant.

I am currently running Volumio DRC on a raspberry 3B and Allodigione ( coax outpout)
Downloading the plugin was piece of cake… However I am unable to get a sound whenever I use the plugin

I would like to make first a quick test without FIR. filter

  1. do I have to set up “allodigione through brutefir” in the settings? (Why the I2S box remains unselected, see question 3?)

  2. Why this bloody AdafruitAdafruitMaxxxx comes in DAC Model?

  3. Why I2S box is turned off after restart?

  4. to make a test is it ok to select “none” for the left and right filters?

  5. What is Dirac filter ?

  6. What is the recommended value for delay and the unit (ms) ?

  7. Is it ok to have the same filter, for left and right? I am using REW+UMIK to create filters

  8. What are the couple of recommeded values for taps (Filter size)/Sampling frequency

  9. My Allodigione is connected to a topping DX3 DAC what is the suitable output format?

I have also downloaded the tools.

  1. Is it a good idea to use the pink noise generator with REW software? ( I could sell my extra long USB wire :wink: ).
  2. What are the recommended values in the first box advanced settings for the number of taps and the sampling frequency when generating the pink noise?
  3. same questions with the option: “mesure with Rev <19”? I assume that Volumio generates a noise which covers the full range of frequencies (20-20 kHz) ?
  4. Can I convert a filter made with REW in a wave file, (using “export impulse response filters as wav” option), and implement it directly in DRC? it would be a great step forward !
  5. Do you plan to implement DRC as a native option in Volumio? I think it is a must!

Many thanks for the answers

hello! thanks! See answers below

I never tested with Allodigione…

No, whait is needed, is to have a working configuration of your DAC beforee enabling the plugin. If ok, enable the plugin, but do NOT try to change anything in Volumio (it should just display something like "allodigione through brutefir’


don’t worry about this. Do not change anything as explained above

Yes, None or Dirac brings no change in sound (sort of neutral filter). Demo filter will affect the sound.

This is a neutral (linear) filter use to test the config in brutefir

There is no recommended value. It depends on your speakers placement. If both are at equal distance from the listening point, let it to zero. In REW, the delay is indicated for each channel.

There is no chance that both speakers required the small correction. The room is not perfect, symetrical etc… You need one filter for each channel

On a RPI4 a 65535 filter is fine

The plugin should detect it. I recommende to reboot after you install the plugin

Yes, the idea is to play pink noise or sweep directly from the plugin to avoid to use long wire or complicated things

Pink noise is 44.1kHz

This REW ver <19 or >19. Nothing to do with frequency response.

Yes you can! You can just export the impulse (one per channel) as wav, place it in filtersource folder and select it in drc to generate filter.
You can get very good results in few clic. But the most important is to make a good measure. Compare sweep with a RTA measure in REW (a least 50 samples). You should get about the same response.
You can also generate filter with REW, have a look here : https://www.audiosciencereview.com/forum/index.php?threads/brutefir-for-volumio-now-supports-rew-eq-filters.7722/

In a short time, it will remain as a plugin, as few user need it… (most people invest in “HIGH RES FILE” or high quality dac or other hardware, but with a single good mic -100€) and DRC, you’ll get x100 a better result… my 2 cents :wink: )

Question for Balbuze -
Hello, and can I add my thanks for this fantastic plugin.
I have everything working but for one small issue, I am hoping you can help me.
My configuration is an RPi 3B and an Allo DigiOne HAT.
The Rpi is running Volumio 2.729.
I have installed latest DRC plugin v1.5.8
The Allo DigiOne sends SP/DIF signal to a Khadas Toneboard with latest v1.04 firmware.
Music is held on an SSD connected to one of the RPi USB sockets.
The RPi gets internet via wired LAN.
I have created my first room measurements using REW and converted them to FIR WAV format using rephase.
Copied the rephase output files to brutefir directory on the RPi and I can see and apply them in the plugin.
Music sounds GREAT!

My only problem. Long term I want to enable hardware volume control (bigger project).
Short term I would like to use software volume control (I know, not as good…).

After I switch on DRC plugin, playback mixer vol control is set to none. I can select and apply software volume control, Save the changes. Says it has worked (green popup) and on the playback window the volume control is enabled, I can set any volume setting, but it makes no difference to output, which is always at full volume whatever I set the control to.
Am I missing something obvious? Is there some way to get software volume control working?



does your DIGIONE support hw volume mixer without the plugin?
If yes, it is still used once the plugin is enabled, even if it appears as ‘none’. Do not try to change it.
If it does not support hw volume mixer, there is no way as the plugin does not work with softvol.

Hi Balbuze, thanks for getting back so quickly.
OK I will stop trying to get soft volume control to work, and move to my plan for hardware volume control.
The Allo Digione does not support hardware volume control.
The Khadas Tone Board does, but as it is downstream of the SPDIF output from the AlloDigione, Volumio does not know it is there, and cannot control it.
I’m intending to get one of these - https://www.diyaudio.com/forums/parts/298816-cheap-simple-relay-resistors-attenuator-rpi.html.

From reading the thread, I think I can take some taps off the RPi 40 pin connector to get the 5 connections this board needs (5v power, ground and 3 signal lines).
Will need some ribbon cable from the RPi to the ARA.
Then I can place it in the stereo analog feeds from the DAC to the Preamp.
If I then install the Volumio Plugin for the Allo Relay Attenuator, the Rpi sends commands to the ARA board to control the volume between DAC and Preamp.

It’ll be a fun project.

Thanks again for the awesome plugin. I think I still have loads to learn about room correction!