How much gain?


I am strongly considering buying either a Denon DL304 or a DLS1. Both of these cartridges have very low outputs (.18mV, .15mV respectively). I am currently running an Audio Technica AT-OC9 ML II through a Musical Fidelity A3cr preamp. The A3cr has a very good phono section (read the reviews below) and is dead quite with the Audio Technica. The specifications of the mc phono are as follows:
sensitivity (for 1V RMS output) 350uV
S/N ratio (ref 1V RMS output) >65dB 'A' weighted
My question is does the mc phono section in my Musical Fidelity A3cr have enough gain to successfully run the Denons?

http://www.audio-ideas.com/reviews/preamps/musical-fidelity-a3cr.html
http://www.soundstage.com/revequip/musical_fidelity_ac3cr_preamp.htm
128x128nanbil
I don't think so. Your AT-OC9MKII is just at that 350uV rating for a 1V output. It is listed at .4mv. The other two carts you are looking at are very low output coils. I really think you will need a SUT, if you want to use the phono stage in your Musical Fidelity. I guess it would depend on how loud you listen and how much noise you can handle?
0.15mv is about 8.5 db less than 0.4mv. If you are presently using the volume control on your preamp in the upper third, or perhaps the upper half, of its range, my very rough ballpark guess would be that 8.5db corresponds to around 60 or 70 degrees or so of rotation on the control.

Therefore, with no music playing rotate the control to a point that is about 70 degrees of rotation higher than the highest setting you presently use it at. See if the noise level becomes unacceptable at that setting, or if you run out of range on the volume control.

It would be prudent to allow some margin beyond that point, to accommodate possible inaccuracies in the specs, inconsistencies in how they are defined, and the fact that the amount of rotation is just a very rough guess.

If you normally use the volume control at or below the mid-point of its range with your present cartridge, then the 8.5db would correspond to significantly less rotation than that 60 or 70 degree estimate.

If an SPL meter is available to you, that would allow you to get a more precise idea of the calibration of your volume control, and eliminate most of the guesswork.

Regards,
-- Al
Thanks for your quick responses.

The MF is hooked up to a set of B & K Sonata M200 mono-block amps running a pair of Thiel 2 2s. They're in a medium large listening room. Very rarely do I get the volume control to the halfway point, and never beyond it. I'm more worried about noise than overall volume so I will give Almarg's suggestion a try.
I'm running a DL-1 through a Pass Labs phono stage using the 76dB setting with satisfactory results.

I found the 66dB setting acceptable but not ideal.

YMMV

dealer disclaimer
Dear Nanbil: The DLS1 is a true high end performer that ask for the best on phono stage. IMHO your A3cr can't do it for that cartridge could shows at its best.

If you don't want to change that preamp my advise is that you go for one of those great ( high end performance too. ) MM/MI cartridges out there. I think that you will be happy with.

Regards and enjoy the music,
Raul.
Rauliruegas

I've never really gotten along with MM cartridges; I've tried several including Ortofons, Regas, Shures, and Audio Technicas, all have been highly regarded but somehow I found them musically lacking. Despite its shortcomings, I really like my OC-9. I've had it for a few years now and want to try something different.