widdly
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Turntable playing too quiet
dbowker
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First off: ALL music you get out of a turntable will be subjectively quieter compared to CD/ tuner/digital or other imputs. I have a pretty fancy setup, and my volume usually starts at around 35 (out of 100) when using phono output and can go up to 70 for really loud. My CD/tuner output for the same volume levels start at 5 and might top out at 40. So, it may be that you don't have a problem, just a new experience.

That being said, if you do have a problem, it could be:

  1. The cartridge is damaged or worn out.
  2. Or, most likely, the cartridge is not a Moving Magnet (what a receiver with a phono amp is usually designed for) but a Moving Coil version. These need significantly more signal boost and usually a specialty/separate phono pre-amp. It doesn't have to be crazy expensive, but most MC phono amps are going to start at $150. For instance, the Music Hall version: http://www.needledoctor.com/Music-Hall-PA1-2-Phono-Preamp?sc=2&category=35249
  3. See if you can get the name and model of your cartridge and look it up to make sure. Or... if it's an older MC you may just want to get a new MM cart. for a less and be done with it.
  4. A long shot is the receiver's phono amp is damaged, but it'd likely sound really bad too.
commsysman
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If a receiver or amplifier has a phono input, that probably means it has a built-in phono preamp, for a moving magnet (MM) cartrdge. There is an outside chance, though, that it is just a regular input LABELED phono with no phono preamp inside.

A phono stage, or phono preamp, does TWO THINGS; it is not JUST a gain stage!

The first thing it does is RIAA EQUALIZATION. This is essential! the 2nd is gain.

Whan a record master is made, the bass level is reduced by a factor of 100 or so by a progressive filter circuit before it is recorded on the record master and vinyl record. If they didn't do this, the bass excursions would make the grooves so wide you couldn't get 2 minutes of music on one side of an LP.

The RIAA equalization circuit in the phono preamp circuit has a triple filter that reverses the process done in recording to restore the bass. If you just plug a turntable into a normal amplifier input there will be only treble; the bass level will be so low it will be essentally non-existent (and even the treble will be weak without an extra gain stage).

Even if the receiver has a phono amp/eq circuit it is probably going to have lousy sound quality.

I suggest that you get the Musical Fidelity V-LPS phono preamp from Audio Advisor for $99; everyone else sells it for $159-189. It is excellent. It will also work with moving coil cartridges which have an output much lower than the more common moving-magnet ones. It has an extra gain stage for MC cartridges only and standard gain for MM cartridges.

Plug the leads from the turntable into its inputs and then its outputs connect to the AUX input or any unused line-level input on an amplifier or receiver.

Look up RIAA EQUALIZATION on Wikipedia for a good explanation  of how records are recorded and what a PHONO PREAMP/EQ CIRCUIT has to do to make the information off of a record usable again.

If you don't have a hum problem, don't worry about a ground wire; if you do, connect one from the amplfier chassis to the metal frame of the arm base or turntable base.

 

 

 

 

 

widdly wrote:

Hi there,

So I just got a Technics 1200 and I've tried running it through a Yamaha HTR-5750, and a Technics AS-203. The Yamaha doesn't have a phono input, but the Technics does. Neither play at a normal level though.  Does anyone have any insight as to why? Also, the turntable I picked up was used and does not have a ground cable. 

Thanks

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