rm5 preamp

parr3n1 · « **on:** 26 Nov 2010, 04:12 pm »

Just wondering if the rm5 is still in production? Anyone have the mk iv? I have an rm9 mkll and have been using an Aethetix Rhea with an audio research linestage and would like to simplify. I am really tire of futzing with tubes, noise, etc and would like to get back to the music. Any thoughts?
thanks

Ericus Rex · « **Reply #1 on:** 26 Nov 2010, 08:40 pm »

I had a Mk III. My understanding is there is no real difference in the design between Mark 1-4. Just number/names of inputs and addition of detacheable IEC power cord. So the Mk IV won't sound any better than your Mk II. I liked mine very much. Very simple design yet very satisfying. The lack of remote control eventually forced me to sell it. I'm getting old and getting lazy.

Why exactly are you using two preamps?

parr3n1 · « **Reply #2 on:** 26 Nov 2010, 11:46 pm »

I am using a Rhea phono section, and the Audio Research for the linestage. The Rhea is a wonderful phono section but you have to be very careful choosing tubes or it can be noisy. I to am getting old and I really would like to enjoy the music and stop spending $$ on stuff . I have become a firm believer that when you solve one problem another is created. My RM9 has really been a pleasurable piece of equipment to own.
Anyone out there have a RM 5 for sale??

Ericus Rex · « **Reply #3 on:** 27 Nov 2010, 12:09 am »

I see. I misread your OP and thought you already owned an RM-5 Mk II.

The RM-9 is a great amp. Still enjoying mine (no remote necessary for full enjoyment!).

A handful of RM5s come up on ebay and audiogon every year. You'll find one there...eventually.

GMuffley · « **Reply #4 on:** 27 Nov 2010, 02:33 am »

The RM-5 has not been in production for quite some time. The main difference between the MK III and MK IV was the detachable AC cord and the ability to turn the phono tubes off in the MK IV. Circuitry and power supplies were identical. Used RM-5s are relatively inexpensive and don't last long when they go on the market. Even a MK II is sonically near the RM- V; the main difference between the MK II and MK III is that the latter had two sets of main outputs.

rbwalt · « **Reply #5 on:** 27 Nov 2010, 03:40 pm »

also i believe the gain switches were done away with in the 4's and 5's. i had a mk2 and i worked well for the 11 yrs that i had it and for the money it sounded quite good.

rob.

Photon46 · « **Reply #6 on:** 27 Nov 2010, 06:34 pm »

Parr3n1, what sort of phono cartridges do you plan on using? In the versions of the RM5 that have adjustable gain, there are distinct differences in the sound of the preamp depending on how the gain structure is adjusted. Personally, I find my RM5III to sound best used with lower gain and wouldn't consider it for use with low output cartridges without a head amp or transformers. It's phono section does sound wonderful when used with higher output cartridges.

parr3n1 · « **Reply #7 on:** 27 Nov 2010, 07:09 pm »

photon, I am using it for mm higher output cartridges. When I purchased the Rhea I was using a mc cartridge and then found my way back to the vintage mm carts.
I am hopeful to find a RM5, the sooner the better. Using a separate phono stage may sound better and or different but the cost of the ic's alone is a game breaker. What associated components are you using?

Photon46 · « **Reply #8 on:** 28 Nov 2010, 01:42 am »

Well, you'll have no problem with using MM cartridges. My phono chain is either a Grado Reference Sonata or an Garrott Optim FGS cartridge, an AudioMods tonearm with integral silver litz wiring loom, and an Acoustic Signature Final Tool turntable. Click on the "systems" link under my avatar photo to see the rest of my system.

parr3n1 · « **Reply #9 on:** 6 Dec 2010, 10:16 pm »

Has anyone used the rm4+? I am not having success finding an rm5 so
I am looking for info about the 4+. I use a mm . I have tried to contact
Music Reference with no success. Is the 4+ still available?
thanks

Ericus Rex · « **Reply #10 on:** 6 Dec 2010, 10:31 pm »

It will take patience to find an RM5. Usually only 3 or so a year come up for sale on the usual classified sites.

wilsynet · « **Reply #11 on:** 7 Dec 2010, 05:02 am »

I'll send you a PM with Roger's email address.

parr3n1 · « **Reply #12 on:** 7 Dec 2010, 05:21 am »

I was able to speak with Sal that works with Roger this evening and he
will help me with purchase of a rm4+. Thanks to all for the responses,
Roger did a good thing participating with this site. I am still looking for a rm5
Thanks

parr3n1 · « **Reply #13 on:** 10 Dec 2010, 04:14 am »

Anyone using the rm4+?? Would like to know
more about it, how you like it etc ????
thanks

nnck · « **Reply #14 on:** 8 Jun 2014, 04:29 pm »

Resurrecting a very old thread here, as my questions are related. Will try posting my questions here first before opening up a new thread, if needed.

I understand from the postings that the phono input on an RM5 preamp can be used on it's own with a mm cartridge. For those of you with experience, has it worked with a high output mc carts as well? Roughly, how high does the output of the cart need to be to work properly with this preamp?

I understand that if the cartridge output is too low, you need to add something like an RM4 headamp or a SUT. But I'm just trying to figure out what sort of carts will work well with the RM5 on it's own.

Ericus Rex · « **Reply #15 on:** 8 Jun 2014, 05:10 pm »

I used a .8mV MC cart with mine. It worked fine. I just had to crank the knob up to 1 or 2 o'clock to get adequate volume. Since there's a pretty big difference between .8mV and the next common output level (.3mV or thereabouts) I'd probably say the .8mV is a low as you'd ever want to go without a head amp.

Chazro · « **Reply #16 on:** 8 Jun 2014, 05:12 pm »

When I owned an RM5 I had great success using it with a fairly low output cartridge; an Ortofon Kontrapunkt b. Sounded great!

Photon46 · « **Reply #17 on:** 8 Jun 2014, 07:00 pm »

I found there was a second factor in decision of what cartridge to use with the RM5. In my system (and as Stereophile mentioned in their review of the RM5,) the sound quality of the preamp was affected by the amount of line stage gain you use. So, if I set the line stage gain high to use a lower output cartridge, I compromised the resulting sound of the system. If memory serves me correctly, I believe around 11db. of gain was optimal for the best overall sound. Because of that , I was never satisfied with a lower gain cartridge when used with the RM5. (maybe using the RM5 with a high gain power amp would negate that problem.) I had good luck with a high output Grado Sonata, a Goldring 1042, and a Garrott Optim FGS (my favorite of the lot.). Have any other owners experimented with the variable gain aspect of the preamp?

nnck · « **Reply #18 on:** 8 Jun 2014, 07:54 pm »

Quote from: Photon46 on 8 Jun 2014, 07:00 pm

I found there was a second factor in decision of what cartridge to use with the RM5. In my system (and as Stereophile mentioned in their review of the RM5,) the sound quality of the preamp was affected by the amount of line stage gain you use. ...Have any other owners experimented with the variable gain aspect of the preamp?

From the look of the posts on this thread, it sounds like some Mk versions of this preamp have the adjustable gain you refer to while others do not. Is this correct?

Photon46 · « **Reply #19 on:** 8 Jun 2014, 10:51 pm »

To my knowledge, all RM5's have adjustable line stage gain, but different versions of the RM5 have different gain settings assigned to the dip-switch settings. Hopefully, Roger will see this thread and correct me if I am wrong.