Success Rolling Opamps in EE Minimax DAC


I'll try to reign in my nearly unbridled enthusiasm for a recent uber-economical tweak, rolling Opamps in the Eastern Electric Minimax DAC.

On encouragement of Chris and Melissa Owens from Clarity Cable I swapped them out (note; this voids the warranty!), with resounding success. A more powerful upgrade per dollar in decades of messing with systems and tweaks does not come to mind.

My brief instructional discussion on this experience appears at Dagogo.com

http://dagogo.com/View-Article.asp?hArticle=841
douglas_schroeder
Doug, you have my nomination for the audiophile "tease of the year" award for 2011 (so far).

Have you ever considered writing for Stereophile?

;)
Njs, Wow, I'm in the lead early on! But don't worry, someone will post/write a hyperbolic, way over the top declaration which will far surpass mine. I'm glad some people are finding I'm not overstating the cause for excitement.

Part of the "teaser" issue is that this project stretched out over time more than I thought it would. Initially I thought it would be one article, one experience. However, it's been developing into a more comprehensive study of the effects of Opamps, so I'm keeping interest alive until all the parts of the Audio Blast are in place. It would be a shame to have what I consider a breakthrough and have it sit unnoticed.

I haven't thought much about writing for an audiophile print magazine. Perhaps I should start one. ;)
Thanks for all you time and effort. Cant wait to hear the news considering I just placed an order for one (very first DAC for my new jolida tube int. amp). For the meantime, I will be enjoying it when I do get it.

Doug, what tube are you using with you DAC?
At the moment I'm not using anything exotic, just the stock 12AU7 tube. The reason is that for testing Opamps I felt it would be far more beneficial to use the stock unit's tube as opposed to an alternative. If I use the stock unit in testing Opamps the results are applicable universally, versus for a subset of those who roll tubes.

I've got a couple others but no time now to work with them post-Opamp rolling.
i own the minimax dac. i have several nos tubes. i believe that if you use the tube gain stage, you bypass the opamp. is this correct ?

if this is correct, it may be more productive of your time to tunr the dac with a tube rather than try to find a suitable opamp.

also, if i am correct isn't the absence of an opamp preferable to the presence of an op amp ??