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Does phono stage noise drive you crazy too?

After using high output moving magnet cartridges for many years, I recently purchased a .5mv output Grado Master 1. I thought that it would be a decent match with my Acoustech Ph-1p phono stage. Reviewers all claim to have used this phono stage with lower output cartridges and had no noise issues that bothered them. I'm just wondering if I'm unduly sensitive to electronic circuit noise, as I find the pairing to be obnoxiously noisy. There's no hum issue, just a "white noise" kind of circuit noise. When I have system volume set to normal highest level listening, I can hear the preamp hiss from the listening seat nine feet away from the speakers. It's not louder than lead-in groove noise, but it contributes to an electronic haze that obscures low level micro-dynamics. I've got the preamp set to 61db. of gain (53db. A weighted noise it turns out.) The Master sounds lifeless and anemic at the lower 52db. gain setting.
Is this state of affairs common? Do many of you just learn to listen through this low level noise haze? At present, it seems that I either need a cartridge with .8-1.0 mv. output to be able to use less noisy gain if I stick with the Acoustech, or I need a phono stage with a better S/N ratio. It surprised me when I started looking for A-weighted phono stage specs, not too many manufacturers seem to want to list that spec.
photon46
almarg's avatar
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almarg
9,670 posts
 
53db. A weighted noise it turns out
What does this mean? Are you saying that at the listening position you measure 53db A-weighted noise with an spl meter, with the volume control at a setting that you would use for listening? If so, that would definitely sound like there is a problem somewhere.

I'm wondering if the hiss could be caused by rfi pickup. Have you tried unplugging power to everything that is not necessary for phono playback, especially the video stuff? As well as turning off any dimmer switches and fluorescent lighting that may be in the area. Also, it would be interesting to know what the noise level would be with shorting plugs connected to the phono stage inputs, at the same gain and volume control settings.

Regards,
-- Al
ahendler
416 posts
 
Isn't there a high output version of that cartridge? Maybe you could exchange yours for the high output version
tketcham
291 posts
 
Hi, photon46, I'm running an AcousTech PH-1P and it isn't any more noisy than several other phono stages I've used. That's with a 0.23 mV output cartridge set at 52 dB of gain. I do wonder if you've got other problems in the signal chain, as the others mention. For one thing, I wouldn't expect such a dramatic change in sound between the 61.5 dB gain and 52 dB gain settings. Something doesn't seem right.

Running the 0.5 mV output Master at 52 dB of gain and letting your preamp take care of the rest should help to lower noise from the PH-1P (IF that's really where the problem lies) but the Master shouldn't sound "lifeless and anemic" at the 52 dB setting.

Regards,
Tom
photon46 OP
1,086 posts
 
Al, I wondered about RFI myself. I experimented with making a copper shield that grounded to the mains plug connection and used Stillpoints ERS cloth to further shield things. There was a very slight decrease in circuit noise, but nothing really noteworthy. The 53db. A weighted noise figure was provided by the factory, not what I measured from my listening seat. Man, that would be loud noise! My wife can't even hear the hiss from the listening position. Like I said, it's not very loud. I'll dig out my shorting plugs and see what happens to the noise level.

Tom, yes I was expecting to be able to use the 52db. gain setting and was most surprised to find it lacking. I'm certainly wishing I'd done my retip exchange for a 1.0mv version instead of the .5 version. Maybe I'm indulging in a bit of hyperbole to say "lifeless and anemic," but at 52db of phone gain, there is a definite lack of drive and "meat on the bones" compared to the 5.0mv Sonata I traded in on the Master 1.
lloydc's avatar
lloydc
752 posts
 
It may just be Grado. try something else. I never found a phono stage that works well with their low output cartridges.
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