I recently picked up the Music Hall dac25.2 & in it's stock form I was pleasently surprised at how good it sounded. But being a tweaker I made a few changes. First I replaced the stock Russian EH 6922 tube with a Amperex NOS Bugle Boy...the difference was not subtle! Next up I replaced the stock op-amps with Burson dual HD op-amps...again the difference was not subtle. Those two DIY projects have literally transformed the dac. Now for my final project for the dac I'm looking for recommendations for replacing the 4 stock output caps. My budget is around 2-3 hundred. I'm all ears!
I have the same DAC and I run a Mazda 7308 tube, a DEXA clock, and I did the Burson's as well. You are correct, a complete transformation of the DAC and I have yet to hear something I like better.
I've not yet tackled upgrading the output caps, but I did try the diode mod and did not hear any change whatsoever.
For caps, I'd contact Parts Connexion by email and ask for suggestions. I got a lot of help from them when modding my DAC.
I posted a lot of my modding journey in this thread:
http://www.canuckaudiomart.com/forum/viewtopic.php?t=12887Good luck!