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Can I use a SUT or head amp with my 60dB Coph Nia MC phono preamp?

Since I use a passive preamp, I am running into low gain issues with my .4mV MC cartridge (Denon DL-301 MkII) and my Coph Nia phono preamp.  The Coph Nia is marketed as a MC phono stage, with a fixed gain of 60dB.  It does have adjustable loading, however, with one of the settings being 47kohm.  So my question is whether it would be possible to use a SUT with this phono stage, and if so, what would the recommended spec be for it?  Or would I be able to use a MC head amp with adjustable gain, such as the Rothwell Headspace (with 4 gain settings between 10dB and 27dB)?  I know there are other head amps out there as well, I just use that one as an example.  

I appreciate the input and education!

Tom
128x128tlarwa
lewm
12,993 posts
 
By the way, if your phono can make 60db of gain, that's equivalent to a 1000-fold gain in voltage.  If the cartridge is making 0.4mV at the standard stylus velocity, the output of the phono stage is 0.4V.  With many if not most amplifiers, this would be sufficient to drive the amplifier at least close to its full output, and stylus velocity gets much higher (faster = more voltage) during musical transients.  So, I think it's the combination of factors I outlined above that leads to your sense of lack of adequate gain from the phono.
tlarwa's avatar
tlarwa OP
6 posts
 
Lewm, I'm driving Klipsch Cornwalls.  My listening position is about 9 feet back.  Line I said before, I can get to the low 90's, which is typically fine.  But I'd like to have more in reserve when I need it.  I'll probably just replace the Coph Nia at some point.  There are a lot more cartridge choices in the .3-.5mV range than in the 1mV range, and I don't really want to be limited by that.  If I had a phono stage that had 66dB - 70dB (or a little more) of gain I'm sure I'd be fine.  I know there are some quality dual mono designs (which the Coph Nia is) out there that get into higher gains like that.  

lewm
12,993 posts
 
The alternate cure is to use an active linestage.  That typically adds 10 to 25 db of gain, and you'd be good to go.  The Cornwalls are ultra-sensitive, to be sure.
lewm
12,993 posts
 
You might even talk to Nelson Pass. He may be able to suggest a way to increase the input sensitivity of the J2.  He's always tinkering with his designs.  That would be a lot cheaper than buying a new phono stage, most likely.  In the price range where the Coph Nia once lived, you might consider the iPhono2.  For $500 it may be a bargain.
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