Convert cartridge output voltage to db gain

Thanks Doug, I don't know if that makes much difference though. It does increase the output voltage from my phono preamp from 0.48V to 0.58V, but that's a relatively small increase compared to the 2.5V that my CDP outputs.

I have read about differences between the two industry standards (CBS and JVC???). I never really delved into it though because the difference seemed rather minor when you're considering the difference in a 0.24 mV output and a 1.25 mV output cartridge. If I do wind up looking for a new cartridge, I can't see considering one with less than a 1.0 mV output regardless of measuring standard.

Cheers,
John

Hi Jmcgrogan2,

I don't have time to run through some of the likely great responses you received on this thread. Holiday activities beckon (happy holidays to all).

In case some of the above advice has you stumped, , I dleve into this issue in a thread on my forum (in the Electronics forum in the Setup and Tweaks section):

http://www.galibierdesign.com/phpbb/viewtopic.php?f=13&t=35.

There, you'll find a real-world example showing how to use an online dB calculator that I link to. The calculator allows you to go both ways - from dB to step-up ratio as well as the reverse.

Hopefully, this isn't redundant, and if it is ... accept my apologies.

Cheers,
Thom @ Galibier

Thanks Thom. Darkmoebius posted a calaculator on his first response on this thread too, It's a little different from yours, but both have their strengths, thank you.

Happy Holidays to all,

John

Hi Jmcgrogan2,

Yes, I hate to post redundant information. Frequently, calculations like this need a working example, and hence the cross-link. Now that I had the opportunity to go through the thread, it looks as if we have everything covered. The posters' names led me to expect this to be the case.

As mentioned above, as well as in my forum thread, sometimes the numbers will show everything to be hunky-dory and yet the system sounds like utter drek - typically due to circuit noise somewhere in the amplification chain.

Sometimes you have a noisy gain stage you can't bypass, and other times you have barely enough gain - a situation where a step-up transformer might bail you out - with some "noise free" gain in the first stage.

The numbers (as usual) are only a starting point, but are(as usual) a useful one.

Happy holidays to all ...

Cheers,
Thom @ Galibier

Thanks to all for all of your help. The problem is solved, though I'm not exactly sure what the problem was, since I made several changes, but my guess would be the problem was using unshielded interconnects.

First, I finally got in touch with Lloyd, and checked the DC offset in my Walker phono stage, it checked out fine. Then, I noticed that I had moved the turntable motor to adjust the belt drive higher on the platter, so I put the motor back into it's original position at the very bottom of the platter. Finally, I changed the 2 meter interconnects from my Walker Signature phono stage to my VAC integrated amp from unshielded XLO Signature 3 to shielded Von Gaylord Chinchilla, and Viola!! The noise floor is gone. Licorice Pizza sounds wonderful again, I'm spinning Jazz at the Pawnshop right now.

I've notice that the volume control knob is lower now, control knob at 11 o'clock. This I can't explain, except that maybe I was trying to turn the volume up louder to hear the music, but in doing so, it also raised the noise floor too.

Anyway, many thanks to all again for all of your help. A happy and healthy new year to all!

Cheers,
John