Matching Pre-amp Settings for Cartridge


Hello-

I have a Yamaha C-85 Pre-amp. I have a Sumiko Blackbird (High Output 2.5mV) moving coil cartridge.

The Yamaha offers 2 selections for a MC cartridge, they are 100 Ohm and 1K Ohm.

Some of the Sumiko specs are the following: Freq. Resp.= 10Hz - 50kHz, Internal Impedance = 135 Ohms, Load Impedance= 47k Ohms

Question; do I select 100 Ohm or 1k Ohm on my Pre-amp phono impedance selector ?

I have more specs if needed.

Also, on rear of Pre-amp, next to phono jacks, is a red button selector. Manual describes red button as follows: Use this switch to refine volume control with "high output  level cartridges". I assume my cart is high level. Press button in to lower signal from cart by 10 dB, press again to release button & return signal to normal. I have it set to normal. Is Normal correct setting for this Sumiko?

TIA, Robes-

robes

Showing 2 responses by robes

Thanks for the reply. Well that's interesting. After getting this Blackbird probably 4 years or so ago I used it on the MC 1K Ohm. probably within playing a total of 4 albums My Preamp burned out and I sent it in to be rebuilt. When I checked it out it was definitely to due with these impedance switches.

Took a year to get back and only yesterday have the system up & running. I have the same MC 1K ohm selected & played 1 album so far, no more. Sounded good but still fine tuning adjustments. So glad I asked this question!!

So, my MM choices are as follows: 47 kOhm 330pF or 47 kOhm 220 pF or 100 Ohm ? I don't know what pF is, and no mention of it in the spec book that came with the cart.

Since you used it at a 38dB gain, I'll leave mine at Normal since the only choice is -10 dB-

Thanks so much, Robes

Thank you once more for your expertise in this matter. You may very well have saved my preamp from overloading again. If I hear a difference between the two 47k selections I'll set to whichever sounds best.

Have a great day and take care! 

Robes