Designing headphone EQ with VituixCAD

[dcibel]

Here it is. You are just looking at the overall gains?

View attachment 185103

Since you have peak of nearly 6dB in that response, just make sure that whatever EQ system you use has an overall attenuation of -6dB so that your EQ stays under 0dBFS to avoid digital clipping.

 

[radix]

Since you have peak of nearly 6dB in that response, just make sure that whatever EQ system you use has an overall attenuation of -6dB so that your EQ stays under 0dBFS to avoid digital clipping.

My understanding of the RME ADI-2 DAC is it takes the EQ gain into consideration when it picks its gain reference level to ensure there is enough headroom. Thanks for the tip.

 

[storing]

My understanding of the RME ADI-2 DAC is it takes the EQ gain into consideration when it picks its gain reference level to ensure there is enough headroom

Doesn't look like that's exactly what happens, but effect is the same: there should be enough headroom for 'normal' EQ. See e.g. https://forum.rme-audio.de/viewtopic.php?id=33773 where this is mentioned on the topic

Does this mean that the ADI-2 with Auto Ref Level effectively applies pre(post?)amp gain - highest gain from PEQ+B/T+Loudness ?
It’s more simplistic:
ADI-2s internal signal processing is done with 42 bit resolution, this is 12 bit or 108 dB more resolution than the audio signal itself contains.
24 dB of this extra dynamic range is used for internal headroom, enough to prevent clipping by i.e. PEQ level boosts.
The Volume control is the final step, and Auto Reference Level does the calculations for you so you can go up to 0 dBr Volume without clipping the DAC chip.

With “Auto Reference Level” disabled, you’d need to watch the Post FX Level Meter to avoid clipping, and manually select you Reference Level - not recommend!
I tried this when I first got my ADI-2, it’s not convenient and distracts from the music.

....

Auto Reference Level calculates the highest gain through the audio frequency range.
This value is used to calibrate the dBr (r = reference) value for the volume control.
0 dBr then is the highest volume that doesn‘t clip the DAC chip.

 

[storing]

But what i actually came here for: had this post stored to look back to when I had time, so that was today, tested everything mentioned and this works pretty well actually. Thanks @dcibel !

Question: are there other ways to get 'SPL traces' into the software apart from scanning an image? It's neat it can do that, but e.g. AutoEQ already has CSV files with the raw response for instance, any way to load that directly somehow?

 

[dcibel]

Scanning an image is actually the least preferred method, VituixCAD is meant to be used with real measured data from systems like ARTA, REW, SoundEasy, Clio, etc.

So you can import any csv / frd type of data, or complete IR to FR processing using impulse response exported directly from ARTA, REW, etc.

For the csv files you have, try simply loading directly to the driver response. Connect driver to source in the crossover to view the response. May need to rename to .txt

 

[storing]

May need to rename to .txt

Spot on, thanks

 

[radix]

I'm posting my vituixcad file for the DT770 which has the RME 5+2 equalizer chain. I've also included the DT770 SPL file created via the process described in this thread. Hopefully this should make it easier for someone else to try the RME 5+2 chain.

usage note: the Vituix project file (.vxp) uses an absolute path to the SPL file, so you'll need to fix that on the Drivers tab to point it to the right location.