Tuning the Sound Card DAC Correction Amp

I have seen many people ask how it's done, so I thought I would just throw this into a thread and hopefully get it stickied up there ^.

So, the basic tools you will need: A Digital Multimeter (Or an oscilloscope*), Small screw driver, a computer, and http://files.getdropbox.com/u/203420/max.zip

*(Though I don't have one so I will be explaining for the DMM, though using an oscilloscope should be pretty straight forward)

Tuning the Correction Amp:

Connect it to your computer, make sure it's properly installed and set on 6 or 8 channels in it's config (Doesn't matter which), and also your default sound device.

Don't play anything through the card, just let it idle while connected to USB, but connect your DMM/o'scope to output 1 and a G on the correction amp. Adjust the OFFSET pot untill it's at 0V, then move onto channel 2 and do the same thing (You can just use the same ground each time).

Then go back to channel 1, and play this file http://files.getdropbox.com/u/203420/max.zip in any media player AS LONG is it supports multi-channel output (most do).

Adjust the GAIN pot on channel 1 until you get 5V, then do channel 2, channel 3 and so on.

Then your done, maybe put a little blob of glue on the pots so they don't move accidentally, although sometimes if you switch computers, your voltages may change slightly, but the tolerance on components used are enough to allow this minor difference.

This should answer a few questions

Thanks Things! When I first attempted to tune my sound card DAC it took me 3 days to find that max.wav file.

I'm going to retune my amp and this helps. muchos gracias.

-Kendall

thanks Things! Drlava also wrote detailed instructions for us which he has allowed me to place in the tutorial. He developed the system, so he's the guy who would know the best way to tune them..