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Phono stage gain too high??? Should I return it??

Just purchased a used ARC PH-7 and am wondering if it is defective as the gain seems awfully high.  I have it running into an ARC LS-27, and it's fed by a Project RPM10 with Sumiko BlackBird Hi Output (2.5mV output, 47K ohm).  I was expecting it to be the lowest gain input in my system, but it's so loud, I cannot set the LS-27 anything over 7/8 (my digital input, Schiit Bifrost is in the 12-16 range), and it does not go soft enough for late night listening.  

The only way I can get it to a reasonable gain level is to set the load at the lowest setting (100 ohms), which totally squashes the dynamic range.

The seller gave me a 30-day return window.  I really like the PH-7 in terms of tone, but is something wrong with it??  It's rated at 57.5 db gain which is modest by most standards, I think.  I have other phono stages rated at 60+ db and in my system, they exhibit LESS gain.  How is this possible??
tswei99
atmasphere's avatar
atmasphere
11,575 posts
 
Do not try to change tubes to change the gain. The circuit is optimized for a particular tube- the 6922/6DJ8.

A higher output cartridge should not be used with low impedance loads like 100 ohms. I don't think low output cartridges should be either but that is a different conversation. The point is that the loading is not how you adjust for gain. It has a different function altogether.

You have several options. One is to go to a lower output cartridge.

Another is to use a passive line section instead of active. IME that really works best if you run short cables from the line section to the amplifier. I'm not a fan of passive volume control systems as in nearly all cases I've seen an active sounds better, but passives can work if the cables are kept short and care is taken in the setup.

A third option might be an input level control at the amplifier input.
wspohn's avatar
wspohn
578 posts
 
It is a sign from the Audio Gods that you have permission to buy new low efficiency speakers - some 83 dB efficient electrostats should have that volume right about where you need it!
georgehifi's avatar
georgehifi
10,312 posts
 

tswei99

All to common problem these days TOO MUCH GAIN! This was why my product was so successful for me. 
 
Sell the ARC LS-27 and pocket quite a bit, and purchase a passive which as Ralph (Atmasphere) suggested, but get this one which also gives you two types of active modes with low gain, one tube and the other solid state, you can switch between the three on the fly, it's remote with probably the best volume pot you can get in it (128 switched relay) it's also xlr or rca.  All for $699.

http://www.schiit.com/products/freya

Cheers George
tswei99 OP
17 posts
 
Just wanted to thank everyone for the advice.  I wound up switching out the Blackbird High output with the Low output version and that did the trick.  It's a great match and things are sounding really, really good.
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