[Sputniks]

I've just got Pro-Ject RM5 SE turntable with Sumiko Blue Point 2 cartridge. I've connected the turntable's output to Music Reference RM-4 phono preamp input. And then to headphone solid state amplifier. The system is playing, but the sound level is very quite, barely audible. Apparently the output signal that is coming out of Music Reference RM-4 output is really low.
On a back panel of Music Reference RM-4 there is a printed note saying there are some input/output "switches" located inside the box to control the output gain and something else... I have opened the box and inspected it inside. Unfortunately I couldn't find any "switches" there.
I have been using THIS phono-preamp (Music Reference RM-4) in past with my another turntable (Oracle) with Orthofon SPU Royal N. And it worked just great. I think the reason must be in difference that exists between Sumiko Blue Point 2 and Orthofon SPU Royal N voltage output. And I probably should set properly those "hard to find" switches that are inside Music Reference RM-4. Here is the basic characteristics of Sumiko Blue Point 2:

Cartridge Type: MC
Output Voltage/Channel 2.5 mV
Load Impedance 47k Ohms

Many thanks in advance!

[Sputniks]

I would appreciate if someone would email me RM-4 User Manual. It is impossible to locate it online....

[Ericus Rex]

If you look here:

http://www.audiocircle.com/index.php?topic=57693.0

...you'll see an RM-5 preamp.  Between the left and center tubes are two red little boxes.  Those are the gain switches for L & R.  I'd imagine your RM-4 would use the same setup.  If you do have these I can send you the settings for an RM-5...maybe they'd be the same for the RM-4.  Let me know.

[Sputniks]

Here is a "Scheme" of the setup I had by the time I started this thread:

Turntable  ---->  RM-4  ---->  Headphone Amp

As I described earlier the problem was in a very low sound level at the headphones even while the volume knob dialed to its absolute maximum position.

The solution was is to place another amplifier that had PHONO IN/OUT integrated.
So, here is what a scheme of the system that works now:

Turntable  ---->  RM-4  ---->  Integrated Amplifier With Phono In/Out built  ---->  Headphone Amp

I have to say guys, that this particular setup does sound great!!!.... I am all happy fellow now 

Here are the elements used:

Pro-ject RPM 5 SE Turntable with Blue Point V.2 cartridge
Music Reference RM-4 phono preamp
DK Design Group MK integrate amplifier (with PHONE In/Out integrated) (it also has tube preamp and solid stage amp).
HeadRoom Max headphone amplifier driving Denon HD5000

The thing I'm concerned about is the size of the DK Design amplifier used here purely because of its Phono In/Out jacks. I wonder if there could be a more elegant alternative/solution than using a full size (HUGE and HEAVY) integrated amp... may be some "stand alone" phone preamplifier would do it?.... strange I always thought that Music Reference RM-4 IS indeed a phono pre-amplifier... If Music Reference RM-4 is not Phono-Preamp, then what is it? And why I can use it only with the amp that has a phono stage in it? What do I have to do IF the amp doesn't have PHONO-IN (like my headphone amplifier)?

[Ericus Rex]

The RM-4 is actually a head amp (or pre-preamp).  It's designed to raise the low-low output of a Moving coil cartridge to moving magnet levels and then go into a regular mm phono stage.  It is not designed to be used without a phono stage.  Your Blue Point no.2 is 2.5mV.  You shouldn't use the RM-4.  The output of the cartridge is high enough without it.  Using the RM-4 might even overload the phono section of you DK integrated.  It makes sense that you don't get enough output with only the RM-4 and headphone amp since there would then be no actual phono section.  Try listening without the RM-4 at all in the setup.  Maybe it would sound better?   

[Ericus Rex]

Sorry I didn't catch the gist of your problem the first go-round.

[Sputniks]

Thanks for you suggestions Ericus!

The problem was in the lack of the PHONO stage in my headphone amplifier. Now I am using DK Design MK. It is quite a massive choice for a such small purpose. I probably should with more economical approach of using PHONO amplifier instead.

[Roger A. Modjeski]

The RM-4 never had gain switches. It had plug-in gain modules. The RM-5 preamp has gain switches for the line section and a complete, passive RIAA phono section. They rarely come up on the used market and I cannot recommend anything better for the price. If I was to make them again the only thing I would do diffrerently is to eliminate the tape monitor (who wants that these days) and add more aux inputs. That is all, I would not change the sonics or circuitry. I'd likely rethink the styling and make the front panel thicker to please the folks the buy more with their eyes than their ears. Like everything else these days it cost more.

Indeed the RM-4 is a very quiet, good sounding head amp. We do make a modified version called the RM-4+ which is essentially the RM-5 phono section in an RM-4 box. The mod is easy to see as it sits very close to the tubes and is an air wired passive RIAA EQ. We sell these units for a very reasonable $950 direct to the customer. I have about 5 left and when they are gone I may make another run but the price will be at least $1500 and I dont know when I will get around to it. I am in the process of building a very large lab.

Now that phono is coming back we need to educate the newcomers to things like RIAA EQ,  cartridge output levels, required amplification, etc. Thanks for all your help in this process.