Phono Amp Spec’s


Hello 

Can someone please help me understand the following…

*Maximum Input Voltage
64dB = 5.7mV
70dB = 2.9mV
34dB = 180mV
40dB =  90mV
 
I would be using a Benz Micro Ruby ZH moving coil cartridge with this phono amp.  
It’s output is rated at .7mV@3.54cm/sec which I believes equates to .998mV @ 5cm/sec.  
 
1.  Am I understanding this correctly, that my roughly 1mV cartridge would be fine going into this 64dB MC input?
 
2.  Is there a way to know what would the dB overload margin would be with 1mV @1khz as well as the low, mid, and high frequencies going into this 64dB MC input?
 
Secondly,
I’m concerned about over driving/clipping the phono amp.
 
* Input sensitivity
64dB = 1.26mV
70dB =   .63mV
34dB = 40mV
40dB = 20mV
 
1.  Can you please help me understand how the input sensitivity of 1.26mV for the 64dB MC input relates to my Benz Ruby ZH with a roughly 1mV output.  
 
What exactly should this mean to me?
 
After suffering 5 major strokes, my memory of many things have been lost. So, if anyone could please help me better understand how the above spec’s would affect me, I would truly appreciate it. 
 
Best wishes,
Don
 
 
 
 
no_regrets

Showing 3 responses by elliottbnewcombjr

"I do have an extremely nice vintage Hirata Tango step up transformer that offers 1:6.6 ratio.  There are times when I get no hum and then other times when I do... it can be frustrating at times.... but when there is no hum - it’s simply stunning!"

That means the sound of your MM Phono is stunning. That is why I use a SUT, to keep using my beloved McIntosh tube preamp mx110z's MM Phono EQ.

You simply MUST find a hum free location for the SUT, put it inside an isolation box  ,,,,, different length or type of cables ..... Don’t walk away from ’stunning’.

Your cartridge's impedance is 38 ohms, they say it should see around a 400 ohm load (that fits the formula 38 x 10 = 380 ohms).

That cartridge: you might need a unit that provides separate control of gain and impedance. My Fidelity Research FRT-4 SUT (gain and impedance are a 'resultant' relationship) to 'get' 470 ohm load, it would be x factor of 10.55 which may be too much signal.

..........................

 

As part of this, can others who have solved HUM from SUTs please let us know what worked.

 

Thanks ahead of time