PrimaLuna Dialogue Premium Preamplifier. DESTROYS SPEAKERS!!

" This failure was most likely due to the system or something in the home.  That's all there is to that. "

Dear Mr. Deal, 
I wonder what, in my home, we can blame, for the failure of your pre amps.

Perhaps it was my beige coloured walls that upset your PrimaLuna's, could that be?
I know, it was probably my green carpet that did it!
No wait, I got it, it was those NASTY Martin Logan/Bryston components,
that's what pissed off your PrimaLuna's!

OK, I have spoken my mind, I will let the Audiogon community draw their own conclusions from what has been written in this thread.

Mr. Kevin Deal, I am speaking to you personally.
In conversing with you on the phone, several times, you can across as 
sincere.

Therefore, I am taking you at your word, that my TWO pre amps were 
FLUKES, and that YOU HAVE NOT HAD ANY OTHER failures, of a similar nature to mine.

I am giving you the benefit of the doubt, as I do not believe you would 
deliberately mislead me, as well as other PrimaLuna owners.

And with that, I consider this issue closed.

Mr. Deal, I wish you well, and good fortune going forward.

George

Thank you. 

George- Unfortunately, it's possible/probable that some of what you have dealt with is caused by living on the bleeding edge.  Sometimes, extracting that last bit of performance comes at the expense of some reliability.  One of my engineering colleagues once told me that there are three variables in every project: cost, quality/performance, and schedule.  When you specify two of them, they dictate the third.  Although I have absolutely zero technical knowledge of circuitry and electrical engineering, of all of the supposed experts that have commented so far, I find Almarg's analysis to be persuasive.  And that leaves aside the circumstantial evidence that the same part failed in the same unusual way, twice in a row.  That, to me, strongly suggests some kind of unusual interaction among the component parts of the system. 

Anyways, the retailer, distributors, and manufacturers involved all stepped up.  You've been made whole.  It's the very rare manufacturer of anything at all that provides warranty coverage for consequential damages. In my recollection, virtually every warranty I've ever taken the time to read expressly rules out such coverage.  You're out some time to replace some circuit boards.  If a fuse blows, do you expect someone to compensate you for the time it takes to replace it?  The other option, I imagine, was for you to pay for shipping the speaker back to ML.  I think you lucked out by having a manufacturer willing to take a chance that you would be able to make that swap yourself without doing other damage, which based on all of the available evidence, you would have then blamed on ML. 

Has anyone actually validated the OP's failures are as stated? Does anyone have eyes on a bad cap?

Best,

E

At the end of the day it will be hilarious if the actual issue  was the amps. I'm not sure the OP can even tell if he had DC or not.

Has anyone else validated his claimed root cause analysis?

Best,

E