Siemens EL 34

@jjss49 "...where i did most of my el34 based listening back in the late 80’s, with early big proacs, spendors, quads, maggie mg iii-a’s".

While I had to move on to different amps/ouput tubes for my main custom speakers 93db/6ohm, aside from triode amps which I no longer own, el34 is still one of my favs. Since my friend who owned the rm9mkii passed on, I don’t think I’ve heard a better musical el34 based amp since. It did get warm and he did go through tubes, usually working to keep a backup supply.

@jjss49 would be interested in learning if you have ever come across another amp that comes close to or beats tine rm9mkii - in your opinion. I do prefer adjustable bias, and amps with top shelf transformers. I do see many of the smaller converted amps some custom builders do, kinda dinky w/baby transformers. I do keep my eyes out for something substantial for a 3rd amp in both stereo and mono amps for EL34s and not referring to smaller transformer amps. I do run QS Mono 120s (big quality transformers) now with KT120s and certain caps and cables I like to try and recapture some of that EL34 sound, yet its not the same type of sultry EL34 sound the rm9mkii and one of my former and larger Cary amps produced.

I might even try to source a custom scratch builder who can build to a higher spec, using the transformers and higher quality bits I want - for a robust EL34 keeper amp. We can take it offline on msg if needed. Thx.

I recently sold my RM9 MK2, despite many telling me to never sell it.  Next to a VAC 70/70 Signature (eight 300B's in push/pull), it was the best amp I've owned.  Time will tell if I regret it.  I have a pair of Quicksilver KT Mono's with KT-150's on order... so I'm hoping they will scratch my itch and quell any regrets I may have in selling the RM9 MK2.

@pdreher I have a pair of Quicksilver KT Mono's with KT-150's on order... so I'm hoping they will scratch my itch and quell any regrets I may have in selling the RM9 MK2.

Thanks for making the correlation and for sharing this update. For one, the KT Monos will run cooler. These Monos should sound quieter, with a darker background.  One thing to note fwiw, KT150s in my QS amps took 200-300hrs to settle in, relax, whatever..before the tone I was looking for started showing up. Some people say they are more linear.  I wanted something closer to EL34s, so I removed the KT150s and now running KT120s, a little more rolled off on top. Will be interested in your assessment after 200hrs on the KT150s in your QS amps.  

@decooney  another benefit to the QS is I'll only be swapping out four power tubes vs. eight power tubes in the RM9 MK2.

Good to know I should expect a 200-300 hour break-in before the KT150's are settled in.  

FYI, there is a Quicksilver Audio group on face book and an EE audiophile there who used to work for QS about 30 yrs ago remarked this about his new KT monos:

KT Monos w KT170s is what I’ve been running for the last 5 months and I’m loving the match. One thing I can say is that you must experiment w bias level. It seems that the KT150s are more forgiving on bias setting. Surprisingly to me, the difference appears in the upper mids and highs and not the bass for the KT170s.

With high gain selected KT170s they can be run in the 60W Monos and that’s not such a great match. More listening to do, as always…