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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!

rajastrums

Showing 7 responses by mesch

mesch
3,529 posts
 
Yes, you need a phono preamp otherwise known as a phonostage. Given that your other components are so inexpensive you might search E-bay for an older Radio Shack phonostage. They can be had for ~$20.  Audio Technica made one that was selling for ~$50, you might search for one of those. I don't remember model number. 

If you are willing to spend more, Schiit Audio sells on for $129 that is highly recommended at that price point. You can also check out Needledoctor online.
mesch
3,529 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.
mesch
3,529 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.
mesch
3,529 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.  
mesch
3,529 posts
 
What is gain on the ProJect Phono Box? Unless the Box has appreciably more gain than the Behringer how is that going to help?

The answers to each of the OP's questions as posted in 4th paragraph are; yes and yes.  We still don't know what AT cartridge is on the Scott TT, therefore don't know the output.

To me the only complicating issue is the relative cost of adding a vinyl system to an ultra inexpensive computer system. One that can closely match the volume levels provided by a CD player. Not that it can't be done.
mesch
3,529 posts
 
The specs listed are for the Phono Record Box E, which in addition to being a phonostage also serves for analog to digital (A/D) conversion of LPs.  The Phono Box is a phonostage only and thus less expensive $60, and yes, if its gain is also 40db it will boost the signal over your Behringer by 5dB.  This would not bring the volume up to that of your CD player however might be enough to satisfy your needs. The voltage supplied by the Phono Box would be about 1.7X that of the Behringer.  I believe Needle Doctor sells the Phono Box, they are good to talk to. Look them up online. 
mesch
3,529 posts
 
Yes, the ProJect Phono Box E.  Has 40dB gain. Seems likely the go-to phonostage at that price point.  Guess not sold by Needle Doctor, sorry. 
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