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
I have owned 3 of these. Every time I sold it, I would miss it and buy another. I have currently owned my last one for approx. 6 years with not an ounce of trouble. These amps are built to last and do run hot as they are biased heavily into class A up to about 20 watts. If you can afford it , go for the mk2. better midrange and fuses for each output tube. Otherwise, get your feet wet and go for the mk1. Best tube is the EL-34, which is the tube Modjestky designed around. Will drive TSM's without even breathing hard. I would contact Bobby first though. He might reccomend something different and less powerful.
I use to own an RM9 and regret selling it. I had the Mark I version which was rated at 100watts per channel, the Mark II is good for 125watts per channel. I used it to power Magnepan IIIA (84dB) and perferred a full set of 6550 from RAM because of their bass control, otherwise this same amp with EL34's is a little warmer. Keep in mind the RM9 is a Singled ended design and has no balanced inputs (not a big deal) unless you have a preamp and cables already. The RM200 is Balanced and has single ended adapters.

Roger of RAM provided excellent support, this is a really easy amp to bias as it has LED indicators on the amp and trip pots next to each quad of output tubes and two for the input tubes. So you don't have to use a voltmeter to BIAS! Once I got a great matched set from RAM it was set it and forget it.

There is also someone selling an RM200 (latest version) right now on audiogon that I would consider. This amp uses only 4 output instead of 8 output tubes and make retubing cheaper but then again the RM9 is really easy on tubes.

This amp is not a TUBEY Sounding amp also, it provide the micro/macro dynamics of a tube but is very neutral.

Regards,
Chris Roberts
Thanks guys for the feedback. Having 8 power tubes in the mk1 do make me consider. It will be rather costly to replace 2 sets of quad pairs of tubes. While still waiting for Bobby's reply on the amp, keep hunting.
I just purchased a pair of maggies 2.7 2 weeks ago. I had own the 1.6 speaker for over 1 year. I have a CJ MV125 amp. 125 watts of power this puts out. Do you think I have enough power to drive these speakers? The RM 9 my friend owns with ProAc speakers. A good sound he gets. Do you still own the maggies 3A? Please respond. Thanks marv
I used to have the 1.6/RM9 combo. The music reference drove the maggies superbly in my 16X26 room. The 1.6s have long been gone, but the RM9 is still the anchor in my system.

Oz
I've had the original RM-9 for ten years. No problems whatsoever. I concur with the above posts but think that the KT-88 is way better sounding than the EL-34 or 6550. Buy one, you'll probably own it for life.
It is an awesome amp,I have owned it for 15 years and love it.I have had no problems with and have changed the stock tubes to winged c el 34.I drive a pair of eminent tech 8 with no problems the combo is killer.
Troyca, what other amp are you comparing it to that you feel it is better than? NAD 3020, or CAT JL2 - know what I mean? What is you comparative context?
I have compared it to nad it is far better,I have compared it to harmon kardon monoblocs,goldentube se 100,it is far better.The only amp that I heard that beat it was atmasphere ma-2 which cost 4 times the price.
I've owned mine for about 5 yrs and couldn't be happier. Interestingly enough, I had occasion to speak Roger Modjeski a few years ago and when I told him I owned a pair of Spendor S100's he suggested I try connecting to the 4ohm tap. I didn't and didn't think much more about it. I was reading a thread somewhere and this was brought up again, so I figured, what the hell, let's give it a shot. All I can say is , Holy Shit!! At 1st I made the switch, turned the amp on and threw on some Latin Jazz, was thoroughly unimpressed. Although the highs sounded clearer and more distinct I felt like there was a bass suck-out. Bass was more tuneful but it seemed that there was simply less of it. Cut to an hour later, I'm reading and listening and all of a sudden my head lifts out of the book, THERE'S the bass, rich, fuller, and deeper while being more melodic. Without being able to measure it feels like I gained an octave at the bottom end! All I had to do was wait for the RM9 to warm up! This sparked a late-nighter, I went to bed at 3:30 in the morning thinking about what I was going to listen to today!. Man oh man oh man, if you own a RM9 and your speakers don't present too demanding a load, you simply've GOT TO give this a shot! Woo-hoo!! Much improved sound without spending a penny! I'm kickin' myself for not listening to Roger years ago!

Bottom line on the RM9; I've never read anything but positives about this amp. Built like a tank, mechanically dependable, year in, year out, exceptional sound that can be tweaked to one's liking in any number of ways. Not to mention how pretty she looks when she's fired up, tubes front and center (I've NEVER used the tube cage!;). Tell ya this much, what I HAVE read, time and time and again, is buyer remorse after selling theirs. IF I ever decide to go with another amp, you can bet yr booty that I won't sell mine, NO WAY!!;)
Owned one a few years ago - a classic tube amp that is reliable and easy to live with.
Back in the '80s I evaluated and bought a RM-9 to replace my restored Marantz 8B. It drove my Vandersteen 2 (whatever was latest version at the time). Beautiful sounding and looking, I might still own it except I bought larger speakers for which 100 wpc was not sufficient.

Looking back, it was one of the finest pieces of gear I've owned in over 40 years in this hobby.
That what I am wondering; how does the RM9 compare Atmasphere, CAT, ARC Ref Series, etc.? I willing to believe they are every bot as good (I don't care about the price difference which I think is relevant at this level). I'm listening to the RM10 MK II - the little 35 watter - and it does not give up much to higher priced stuff. Next week I'm bringing the RM10 over to compare with a fella that has the RM9Special - should be interesting as we both own the same speakers.
I'll say one thing, I've never heard a bad word said about a MR amp by anyone who has owned one.
Nice to see a current thread about this amp. I've owned the RM9 for just a few months, after buying it from the 2nd owner here on A'gon. I'm only a couple of years in the hobby, so no expert my any means; but no complaints about this amp. Love the looks of it in the dark (never put the cage on after I got it - looks like a cityscape at night) It came with RAM labs 6550's in it and am wondering what I might expect if I changed to KT 88's. Anyone care to give an opinion?
CD source is a Shanling T80 with RCA black gates, fed directly into the amp, through some TaraLab cables to Quad 22L2 speakers.
Has anyone experimented with different driver tubes?
Thanks in advance for any input.
I have sold my RM10 and a RM9 MKII is on the way. I am very interested to see how it compares with my CAT JL2 - it owuld be nice to go from 16 output tube to 8; if the sound is of comparable performance.
The two front driver tubes will have a audible effect on sound quality. I've settled on NOS Amperex orange globe (Holland) a-frame 6dj8. Very smooth but still detailed.
I used the 6N23P tubes as well. Well worth it sound wise and very inexpensive. Otherwise the Siemens NOS worked for me too.
Clio09, are you alos using a passive? I just got a "Pot-in-a-Box" from Roger ($135)and I'll be darn it sounds really good. Better than the Joule? We'll see, I need some time with it, but it is a steal based on sound.
Pubul57,

I used my K&K Audio TVC with the RM9 and it was a great match. This was back when I lived in Santa Barbara and was able to visit Roger to have the RM9 upgraded to MkII and found he prefers it with a passive pre. He ran an RM200 with the pot in the box with his new electrostatic speakers (these are phenomenal for the price). A great system. I wouldn't be surprised if it gave the Joule a run for the money. I sold my LA-100MkIII when I got the K&K TVC.

I no longer have the RM9 as the guy I bought it from bought it back from me. However, I am considering a system reconfiguration and trying a set of new speakers that may be a very good match for the RM10. Rogers amps are excellent.
Very interesting. I've been using the Music Reference Pot-in-the-Box today (just got it) with the CAT JL2 and it blew me away how good this thing sounded in absolute terms, and ridiculous for $135. I've got the RM9 MKII coming next week and am eager to try it with the passive; I did not get a chance to try it with the RM10 MKII which I just sold this week, a very sweet 35 watts. I know me, and if this passive works wonders with the RM 9, I'm going to start thinking about stepped attenuators, transformer/autoformers....
I auditioned Ozzy62's system several years ago. He used an RM9 with a K&K TVC, the sound was phenomenal! I'm a former owner of the MK2..terrific sounding amplifier...I wish I still owned one. These particular tube amplifiers have plenty of gain, making them passive friendly. You should at least try a TVC with it just for grins.If you like the pot..you'll love the TVC!
I have not used a TVC, but did have a Placette RVC and Placette Active at one time. I think Roger's Pot-in-a-Box with 30-year old + Noble potentiometer actually sounds better than the Placette RVC. I am curious about the transformer based passives, but I do wonder why Roger who can build whatever he wants thinks that is not the best approach, especially with his amps. I have to assume that a transformer must add distortion to some degree compared to pure passive volume control, and that it must be less than linear across the frequency spectrum, most notably on the extreme highs and lows - but I'm no engineer. I do know that with my source, short run of Cardas GR (super low capacitance)and both Roger's amps and my CAT JL2 with high sensitivity and high input impedance I have a pretty ideal set-up for a pure passive set-up. I'm not sure that a TVC might not be subtraction by addition in my case. I'll say if you have a RM10 or 9 and you have not tried a passive volume control you owe to yourself to try it, no matter what active linestage you are currently using. And if you are on a budgetm I can't imagine a much better entry level system than a Pot-in-the-Box matched to a used RM10.
I got the K&K TVC with dual volume controls and it works very well with RM9 and CAT JL2, but the Joule has its own charms so I guess I'll own two preamps (I mean 3) for a while. I placed an order for the RM9 Special Edition, I think EL34 based tubes amps work particularly well with my Merlin VSM-MXes. The Music Reference RM9 is the first tube amp I've had that has me seriously considering selling the CAT, which remains the best amp I have ever heard.
Plz follow up with a review of the RM9 SE. I'm a long-time RM9 owner and only recently have learned of the existence of these 'super' RM9's. I'm very interested about this amp.
Chazro, just to let you know. Roger built 18, kept one for himself, and has 5 or 6 left. I will report my observations once I have some time with it. Basic difference from a design perspective is that it is all hardwired, no boards, and uses a 6 tube driver stage (6bq7s) instead of the four 6922/6dj8s. I think he also put in some heavy duty bias pots and other tinkerings. I assume it is his most evloved thinking on the basic Ultralinear (8) EL34 tube design. One advantage over the CAT is I can pick it up:)
I run an original RM9 that Roger went through, upgraded and re-tubed with RAM KT88s last summer. The KT88s offer more midrange texture/detail and the bass is superior to the EL34s. The result is a truly outstanding amp.

I'm using the Benckmark DAC-1 with it's level control and it sounds great. Not quite as minimal as Roger's pot in a box, but I like not needing another piece of gear in the chain.
Well I have had the Special Edition and it is a big step up from the MKII - not sure why as the output stage, layout, power supply all remain the same, but Roger completely redesigned the input drivers, making them point-to-point (no more boards) and uses six 6bq7s. The amp outputs 162watts into 8ohms and 200 into 4ohms, so it is more powerful, yet you can still expect 10,000 hours of tube life. This amp is fantastic. Is it better than the CAT JL2? I certainly won't say that; but they are bot first rate and the ergonomic (weight, heat, tube costs) are certainly the RM9 SEs favor. Anyway, I don't know how many of these Roger has left, but he won't be uilding anymore and they are a timeless classic in my book. Like my Merlins, I expect these to be a long time companion.
I have the same RM9 MKI that I bought from Johnny Rutan at the Audio Connection in 1987. I have had it worked on 2 times in 21 years. It is currently tubed out with Genelex Gold Lion re-issues and 1960s Heerlan Plant Amperex E88CC. Make no mistakes about the tubes I tried them all and there is no comparison with the KT88s. I am currently Driving a pair of Merlin MXE's and it sounds to my ear beautiful, super balanced and as pleasant as it gets to listen to. I have heard systems that had $40,000, wrapped up in them and-well sorry I can't help you there. The RM9 is a timeless amp and I will never sell mine. I have an ARS Sonum integrated on the way we'll see how they compare. I say get one and save yourself $10,000.00
I'd like to hear some of the 980 owners of RM9s as to their preference between EL34 and KT88; there seems to be quite a difference of opinion on the issue, and there is a comparison to be made; certainly Roger is not so definitive on the subject. I think in the case of Merlins, their is an expecially strong case to be made for EL34s, but ultimately, it just may be a matter of taste.
Used full range, I much prefer SED 6550 in the RM-9 MkII over the El-34, primarily because of the increased bass drive and impact the 6550 affords. The ultimate choice is, of course, system dependent and influenced by listening preferences. For large scale orchestral works (Mahler, Rachmaninoff, etc.) and full-range speakers, the 6550 does it best for me.
Well, there you have it, the EL34, 6550, and KT88 are the best with the Music Reference. Frankly, I suspect they all sound great with different flavors though I owuld note they were designed with EL34s. I'm not sure how much difference there is between my Special Edition and the MKI&IIs, though they do have completely different driver stages (6 6BQ7s). I think is this is one of those question with no definitive answer that applies beyond the individual with his ears and his system. But I would like to try KT88s some day.
Well, there you have it, the EL34, 6550, and KT88 are the best with the Music Reference.

Actually this is true. Depending on the rest of the system, the room, your preference in music, and so on, each tube's characteristic will slightly tailor the sound.

I keep my pair of Quicksilver Silver 60s for their wonderful midrange presence and classic tube sound courtesy of EL34s. My RM9 on the other hand just kicks butt with the RAM KT88s. More of everything and at the same time more neutral and NOT tubey sounding.

I just bought a barely used original Rm-10 for my office. With only 200 hours on the amp and the original RAM tubes I've got to tell you it does sound like a mini RM9.
The RAM KT88s are the slight more expensive one's he sells? $65 each? Or are you using the Chineese KT88 he uses?
Roger went through my 17 year old original RM9 last July, upgraded it to a MKII and retubed it with all RAM tubes. The KT88s are the more expensive ones @ $65 and worth every penny.

The amp sounds amazing.

I just bought an original RM10 with only a couple hundred hours on it for my office. After listening to the RM9 at home I had a hard time listening to my Pathos Classic One II at work. I had to have that MR sound.
What tubes were you using prior? His EL34s? (Siemens?). I take it that if you made a change it was at Roger's suggestion? How did the sound signature change? I guess I could just buy them and try.
I was running the original EL34s that the amp shipped with and the amp sounded great. Talk about long tube life! Roger's statement that you'll get up to 10,000 hours on a set of tubes is realistic based on my experience.

Roger's suggestion to go to the KT88s was because I expressed curiosity and he thinks the RAM KT88s he's selling now are some of the best. I have to agree.

The change is sound was significant, tighter bass and midrange detail that took a great amp and made it even better. Soundstage is more defined by the added detail.
Regarding different tubes - my RM-9 (#121) came with Sovtek 6550's when I acquired it from the 2nd owner last August or so, and that's what I've kept in it. I've made so many other changes to the rig, though, (CDP, speakers, and now the PotInABox) that it would be difficult to nail down any sound trait that I could characterize as 6550 related.
But what I have played with some are the driver tubes. From the original RAM 6922's, to the 6DJ8, to a GrooveTube 6922, and just a couple of days ago, a pair of Tesla E88CC's.
Its probably a little early to say definively, but it seems I've got a bit more detail, a bit more air around each instrument with the new Tesla's. For instance, on a track from Dave Brubeck's Time Further Out, I noticed the rattle and decay of the standup bass notes more than I'd heard before.
But one thing I've learned about this hobby is that most tweaks render pretty subtle changes, and it may take some time for the improvements or detriments to reveal themselves. For now, I think the Tesla's are a positive.
I do have an octet of TungSol 6550's on the way. It will be interesting to see what happens when they're installed.
What did the Pot-in-a-Box replace? I use one and a Joule 150MKII. Not bad for $135 - is it?
Nope, not bad at all, even at the $195 for the 2-input version, which I got.
I had been feeding the Shanling CDP directly into the amp, using the built in volume control. My theory was that I was probably losing some detail and information from the CD with the digital volume, and that there would be a benefit of keeping the CDP at full volume and using the PotInBox.
Rig has been sounding very fine, though I've got fairly new Quad22L's that I think are starting to break in, and new driver tubes this week, so its hard to say what component of the great sound is due to the P.I.A.B. And the new Tung-Sol 6550's are due tomorrow.
Weren't you using a Promitheus TVC for a while? I'm interested in trying the C-cores a bit further down the road.
I was using a K&K TVC with S&B 102 MKI xformers and dual Sieden switches. An excellent piece, but I can't say I preferred it to the PiaB. I've got the Siemens EL34s in the RM9 SE, and just ordered a set of the KT88 RAMs. I've got some new SED Winged C 6550s that I am also go to try. I usually have 2 or 3 amps, but I think I might like the idea of one amp, three sets of tubes. Fortunately, I don't thing I can really tube roll (not sure why I would) the six 6bq7 driver tubes.
I've got the Siemens EL34s in the RM9 SE, and just ordered a set of the KT88 RAMs.

I hope you'll post back here after you've had a change to try the KT88s and let us know what you think.
Has anyone compared 6550 versus KT88 with the unit? They should be pretty similar, no?
Well, I got Roger's KT88 RAM and let's just say that I sold my back up set of Siemens EL34s (still have the originals). It (RM9SE) sounds like a different amp with the KT88s. Better dynamics, more controlled and tuneful bass, and bigger, more expansive soundstage. I've just ordered a set off the Genalex Gold Lion reissues from Jim McShane - just to see what they are all about. I wasn't expecting to prefer the KT88s, as the RM9SE was built around EL34s, but I personally prefer the amp with them, but I'm keeping the EL34s around.

I also recently bought Bent's new TAP with autoformers which is the best passive I've hard so far (owned Placette RVC and Active, K&K SB102, Goldpoint Attenuator, and Music Ref PiaB - and most recently ARC, CAT, LAMM and Joule tube actives). One heck of a good combination and not very expensive for a SOTA preamp. Passives do work great with the RM9.
Interesting on the KT-88s. I myself have always preferred EL-34s. I thought both my Cary V12i and my RM-9 MkII sounded great with the Siemens. Right now I'm using a VAC Avatar SE with the National Electric EL-34s, but am getting a set of Auricle Musicblocs with the VAC (Chinese) KT-88s this week. The VAC guys like the KT-88s and feel the Musicblocs will present a larger soundstage and more frequency extension. Should be interesting to hear the differences.

Glad you like the Bent. I'm a going to be using balanced cables now so I'm waiting to see what John comes up with for a balanced design.
He should have something soon. Apparently a balanced autoformer design is a bit trickier than with a transformer. I was expecting to prefer the EL34 as well. Does the Avatar also run KT88s, or just EL34s?
The Avatar and Avatar SE run EL-34 tubes only. I believe the Avatar Super runs KT-88s.

Autoformers are a bit more work to get into balanced mode. John is a bit of a perfectionest so I anticipate a good 6 months or so before something becomes available. Until then I'm sure my Jeff Rowland Capri with phono will do just fine.