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Phono Preamp Settings/Question - Help Please

Hello, I'm considering purchasing a Musical Fidelity MX-VYNL phono pre, however I'm having a terrible time figuring out if this unit is compatible with the rest of my system. My cart is a Nagoaka MP-200 (4mv) and I am using a passive preamp into an amplifier with 26db of gain. I've calculated that I need 53.4db of gain to get a full 2v ouput from the preamp. I can't read this spec sheet... usually phono preamps have a list of db step-up settings however I cant find them here.... am I missing something? Not by any means an expert but I know enough that I need to get this right. Likely will be running the balanced outputs.

Thanks for any help/insight!

http://http//www.musicalfidelity.com/uploads/catalogerfiles/mx-vynl/4_MX-VYNL_manual_issue_1.pdf
ajnackman
8 responses Add your response
folkfreak's avatar
folkfreak
1,349 posts
 
The phono stage has either (appx) 52 or 58dB of gain on the MC setting, the higher number with the +6dB switch engaged. This is based on the spec (p5) of 0.3V out for 0.8mV in. For MM it’s 36/42dB

However this assumes you use the MC inputs and you actually have a Higher output cartridge, the overload limit on the MC input is only 12mV so I’m not sure if you’ll have a headroom problem

Good news is you can also select 47k loading and it seems use the MM capacitance settings while using the MC inputs so at least that’s not a concern


ajnackman OP
60 posts
 
So presumably I would use the MC inputs, even though I have a MM cart, which would provide more gain without any loading issues because I can select 47k? Curious what the overload limit spec means.
folkfreak's avatar
folkfreak
1,349 posts
 
Correct, as to whether you will have enough headroom I suspect it will be fine as long as your record diet is not primarily house 12” singles (see here for a discussion of what the 1kHz 5 cm/sec means https://repforums.prosoundweb.com/index.php?topic=26987.0)

i do worry however about high frequencies which per RIAA standard are 20dB up on 1kHz, you’ve only got 10dB of headroom but how many tracks have full scale recordings at 10kHz and up? Let’s suggest you steer clear of test records!
ajnackman OP
60 posts
 
Thanks for your input and the resource!
Post removed 
ajnackman OP
60 posts
 
My amp's sensitivity is 2.24v, however its a 500W amp and I've had plenty of success with 2v out from my dac directly driving my amp. I have kef ls50's which I believe are 85db sensitive.
Post removed 
ajnackman OP
60 posts
 
The input impedance of my power amp is 50kohms so I think that should be okay there given a 1:10 ratio even if the spec isn't listed on the musical fidelity. My passive is a TVC so that wont hurt impedance matching either.
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