Sonic Frontiers Phono One: Gain too high?


Hello,

I'm trying to help a fellow 'phile troubleshoot a problem with his Phono One. He claims that he cannot use anything except very low output cartridges with his Sonic Frontiers phono stage because he has the "high gain" version. Evidently there were three different versions of the SF Phono One: a low gain, normal, and high gain? I looked through the manual and on page eight it describes how to set the dip switches for various cartridges, even has two user defined positions (using add-on resistors and capacitors). No idea why he couldn't fiddle with these settings to dial in the step up.

So... can a "high gain" Phono One be set up to accomodate high output moving coil or moving magnet pickups???? Thanks much, Jeff
jeffloistarca
The gain cannot be changed by the end-user. I used to own the "high gain" version, which had 62db of gain. This should be used with MC cartridges of no more than .6mv of gain.

For more information:

http://www.anthemav.com/OldSitev1/pages/phono.html
gain was as stated not readily adjustable unless a tech removed and added the necessary ??????.

gain of 62 58 or 54db were the three hardwired choices offered by SF
Why Kenny? If my math is correct wouldn't 0.6mv with 62dB gain only be 0.75v? Isn't line source 2.0v? Wouldn't a 1.5mv cart be 2.0v after 62dB of gain? It always seemed that phono stages needed more gain to me. Else don't you have to relay on your linestage to provide a bunch of gain?

dB gain = 20 * log (V1/V0)
10^(dB gain/20) = V1/V0

I have a Hagerman Bugle with 40dB gain and a dynavector 20x-h with 2.5mv output, and I'm considering changing the gain to 50 or 60dB with a resistor change.