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How to increase volume of my turntable - pre-amp - amp setup

Hi. Good Day to you all! My first post and first visit.

I have a cheap Scott turntable equipped with a low priced Audio-Technica mm cartridge through a cheap Berhringer pre-amp into a Logitech Z-680 speaker system. I also have a CD player separately into the system.

The volume output from the speakers is markedly lower from records than from CDs. I suppose that CD medium might be a little louder (the loudness war thing?) than vinyl but this seems to be an output problem not a difference in mediums.

I would like to increase  LP volume. How can I do this? Can I get a higher output cartridge for my turntable? How about a pre-amp with higher output? The Logitech speaker system seems plenty powerful.

I've researched but can't seem to find an answer that I understand. 

Thanks!

128x128rajastrums
mesch
3,520 posts
 


Which AT cartridge do you have?  MM cartridge gain is measured in milli volts (mV), usually running from 2.5 to 5 mV. Phonostage gain is measured in decibels (dB), Most budget MM ones usually run from 34 to 50 dB. Do you know the gain of yours? Knowing these values would help to derive the best cartridge/phonostage combination to achieve your goal.

A doubling of voltage provides a 6 dB increase in gain. A 9-10 dB gain is required to provide a doubling of perceived loudness. The output of your CD player is likely 2.something volts. Your cartridge/phonostage is likely putting out ~1 volt. Therefore the CD player provides ~6dB of gain over your cartridge/phonostage combo.
georgehifi's avatar
georgehifi
10,312 posts
 
His Behringer phono stage has 35db of gain.
https://media.music-group.com/media/PLM/data/docs/P0492/PP400_P0492_S_EN.pdf
But if he needs more gain, a stepup transformer or s/s headamp will do the trick before the Behringer.
http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2050601.m570.l1313.TR0.TRC0.H0.Xphono+steup+transformer.TRS0&_nkw=phono+steup+transformer&_sacat=0

Cheers George
mesch
3,520 posts
 
I believe he needs a phonostage with higher gain or a cartridge with higher output. At 35dB of gain he is not getting even 1 V output from cartridge/Behringer combo. If my calculations are correct it would require 46dB gain from phonostage to get 1 V from a 0.5mV cartridge, based on dB output = 20 x log(1/.005). 

Still wonder what AT cartridge he owns.
lowrider57's avatar
lowrider57
5,417 posts
 
I have a cheap Scott turntable equipped with a low priced Audio-Technica mm cartridge through a cheap Berhringer pre-amp into a Logitech Z-680 speaker system. I also have a CD player separately into the system.
If the Berhringer is a phonostage, then I assume all sources are plugged into the Logitech. There are no specs listed, but it accepts line level inputs.
The budget AT carts I looked up are rated at 3.5, 4.2, and 5.0mV at 1 kHz. So it seems that a MM cart into a phonostage with 35dB gain is too low.

https://www.amazon.com/Logitech-Computer-Speakers-5-Speaker-Silver/dp/B00007AKDP
mesch
3,520 posts
 
Yes lowrider, I was afraid the OP has one of the budget AT cartridges that had the lower output which would not be suitable for the loudness levels desired with a 35dB gain phonostage. If so, a 5mV cartridge may provide the volume needed but not be equal to the CD player output. A 5mV cartridge and a 40+ dB phonostage would serve much better.  
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