Music Reference RM9 - user comments please


I am considering of getting a used RM9 for my Merlin-TSM, can any user of the amp comments.
vintage
Pubul: I suspect that Roger gave you a set of matched tubes. In my experience, tube matching makes a huge positive difference in the sound. It sounds like you have ordered another set of KT-88s from another supplier. Will these be matched as well?
Roger's tubes are amazingly well matched in circuit. It really makes me question some of the folks out there selling "matched" pairs and quads. I won't name names but you do wonder if some of these tubes really are matched. Roger's are for sure. I ordered the Genalex from Jim McShane who seems to have a good reputation for taking care in matching tubes. They arrived last night, and I will run them tonight and check their bias in operation.
I installed the KT88s (Genalex from Jim McShane) and they bias perfectly (all within 5%) which is very encouraging. He seems to be really matching the sets. The Genelex sound great, but I'm going have to A/B for a while to see if I prefer them to Roger's - it may not matter one bit as the amp sound great with both. I think one can feel comfortable buying from either Roger or Jim - and of course Andy at Vintage Tube Services for NOS.
Well, I still own the Music Reference RM9 Special Edition, I still love it, and I don't think I will ever sell it. After a few years, I starting missing my RM10 MKIIs, and bought them again this week - if 35 watts is enough power, it gives the RM9SEs a run for their money (the RM9SEs are 5x$$$), but of course the RM9SEs will drive many more speakers, including tough loads (e.g., Theil). They look beautiful, the sound wonderful, and they appear to be made to outlast you. While perfer the Atma-sphere amps with my speakers (Merlin VSMs), there is no way I'm selling the MRs, they are amps you can live with as long as you still listen to music, and the only remorse is if you sell them.
Clio9, after a lot of experimenting, and too came to the conclusion that with my speakers, the EL34 approach worked best, though the KT88s were pretty darn good, and different sounding, a different amp with that tube change.
Well I bought another VAC amp a couple weeks ago that uses EL-34 tubes and still come to the same conclusion. In a recent conversation with Kevin Hayes he mentioned the VAC Auricle Musicblocs can be rewired to accept EL-34 tubes. I'm seriously considering having this done. Less power output, but with my speakers that should not be a problem.

I was very tempted to buy one of the RM-10 MKIIs that came up for sale recently. In hindsight I should have.
Anthony, there is another one up for sale. I bought the other. I think they will love your speakers.
I have some nice EL-84s to roll in that amp. I will listen to the RAM tubes first though. For 12AX7 I have some nice GE 5751s I'm going to try too.
I asked the question on another forum, you ar sure the 5751 is perfectly ok in the circuit? One thing the RM10 doesn't need is more gain, so I would think that would not be an issue.
I don't see why not. I'm definitely going to try it for the same reason you're considering it. I get my amp Thursday. I'll let you know if it blows up upon use of the 5751s.

FWIW - I have a Berning Micro ZOTL I'm using as a preamp right now. It comes with 12AT7 tubes, but I have been able to use 5751 and 12AU7 with no issues. The 12AU7 lowered the gain the most. I may even try 12AU7 tubes in the RM-10.
03-07-10: Pubul57
Well, I still own the Music Reference RM9 Special Edition, I still love it, and I don't think I will ever sell it. After a few years, I starting missing my RM10 MKIIs, and bought them again this week - if 35 watts is enough power, it gives the RM9SEs a run for their money (the RM9SEs are 5x$$$).....

You know, with the Merlin VSMs it just might be that the 35watts from the RM10MKII is all I really need. I am even thinking of maybe selling my RM9 Special Edition, if I could convince myself I would not have instant buyer's remorse and the fact the Special Editions never, ever seem to come up for sale as Roger only made 16 and I get the feeling most owners will sell it at an estate sale. But, the RM10 is one hell of amp in my system.
Well, I did end up selling the RM9SE and kept the RM10 MKII for the summer
months. No question the RM9 is one of the finest tube amps there is, but the
RM10 is a wonderful amp if 35 watts is enough power for you - among the best
IMHO. Truth is, if Roger Modjeski makes it, it will be a good amp. I do wish
Roger would make an active tube line stage to match with the RM10, but he
believes passive is the way to go, and I'm not at all sure that any preamp would
better my Lightspeed Attenuator matched with the RM10, but still...:)
I own a RM9 MK1 with KT88 tubes.
I think it is a wonderful amp.
Can anyone tell me how much needs to spent $$$$ to better this amp significantly.
Thanks
I think you are already at the forefront of what you should expect from a great tube amp at that power rating - changing to EL34s will give you another sonic signature though.
I just stumbled on to this thread. Brings back great memories: After many years of SS I bought my first tube amp in years, it was 1996, I think, and I bought the remarkable RM10 MK II from John Rutan at Audio Connection in Verona NJ to pair with my Sound Dynamics 300 TI. I've always regretted selling them. And a shout out to John, he definitely knows his stuff, and is one of the truly nice guys in audio.
Send it in to Roger and get the amp upgraded to MkII status. You already have a well designed amplifier to begin with and to better it you'd have to spend as much as an RM-200 MkII, maybe more if looking at other manufacturers as well. Upgrading to MkII status will give you the most bang for the buck. When I owned my RM-9 MkI it's exactly what I did so I speak from some experience.
Not sure what Roger did from I to II, but I do know that he does makes this changes unless they are real and substantial, so as Clio9 says, that might very well be a worthy improvement - the RM9 is a classic, might as well go to MKII.
Thx for the input guys. A phenomenal amp.
I have sent an email to Roger inquiring about the upgrade.
Clio09 - can I ask a few questions?
How did the sonics change with the upgrade ?
Do u remember what got better what worse - or was it all good ?
What speaker/s are you basing the impressions on ?
Much appreciated.
You should go to AudioCircle and join the Music Reference forum, you'll find lots of answers to your questions, and a possible reply from Roger himself, or Music Reference lunatics that know the equipment well.

http://www.audiocircle.com/index.php?action=circles
When I owned the RM-9 I was using Spendor 1/2e speakers. The RM-9 was the only tube amp I tried in my system that I liked with the Spendor's. Normally I have used solid state with them. At the time I owned the RM-9 I lived just a few miles from Roger. So I took the amp over there and he bench tested it with me. Darn if it didn't operate nearly 100% to spec, and put out more watts than its rating.

The upgrade includes the addition of chokes, and new caps in critical places. I think he makes some other changes as well but forget what they are. Roger also does a thorough inspection of the amp and brings it to full spec in all areas. Upon picking up the amp the bench test indicated it was putting out nearly 125 watts/channel. Up about 20 watts from the previous test. As for the sound, I felt the MkI was a bit tubey in nature and with the MkII you will be getting a more transparent and neutral presentation. I myself liked that. I did end up selling the RM-9 and somewhat regretted it. Now I have both an RM-10 MkII and EM7-12v SET from Roger with much more efficient speakers and these sound wonderful.

Be patient with Roger on emails. He is hard to reach as he is quite busy. I suggest you try to reach him through Sal at Audio Summa. You might get a faster response and more information to help you make a decision on whether or not to upgrade.
"transparent and neutral presentation" seems to be his design goal, with no apologies to SS, but with the bloom you can only get with tubes.
I have had some people tell me they prefer the MkI versions of both the RM-9 and RM-10 because in their opinion they had more tube characteristics to their sound while the MkII versions sounded more like solid state. I think that is the knock on the RM-200 as well. It is pretty obvious that the MkII versions of the RM-9 and RM-10, as well as RM-200 sound characteristics will never be confused with classic CJ or Cary, but all three still sound like tube amps to me, and very good ones.
Clio09 – thx for the impressions. Yes I have read reports in the past about preferences between 1 and 2 versions. It really helps when you are close to the manufacturer for repairs / upgrades.

Pubul57
Well I just completed 3 years of what could easily be defined as analog Lunacy - so heh - why not use that as a lead into some Amp/Preamp Lunacy now.
Thank you for the link.
I owned an RM-9 mk I for 10+ years and had Roger replace the on/off button (most failed) add mk II chokes and move the fuse holders to the top plate. In many respects, I sadly regrets selling that amp. The El34 Seimen tubes in matched Quads from RAM Labs were remarkable and had a midrange magic that was fantastic on several pairs of Merlin speakers I had/have owned. I wish I would have kept amp.

Highly recommend output and V1 V2 tubes from Roger. They sounded the best and not be a little I may add.
"I sadly regret selling that amp." You don't know how many times I have heard former MR owners say that... fortunately it is still easy to get RM10s.
updates ? i have an RM-9 w EL34, one Phat sounding amp light loading the transformers per Roger into Vandersteen Treo CT. In my system, i prefer the RAM EL34 to RAM KT88. I am using all RAM drivers. I am also about to build pot in a box.

Finally, RIP Roger - a true Audio genius.

best to all

Jim