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Noise from phono. Help please.

Recently became an analog fan and currently experimenting with different phono stages (ASR basis excl., ARC Ph7 and ayre p5xe.) System includes Avid Acutus, triplanar arm which comes with RCA connectors and ground wire. ARC ref3 preamp, VAC amp and Avalon speakers. System is quiet with cds but when a phono was added, noise became an issue.

The Ayre is very quiet and there is very faint background noise that is not audible at 8-10ft from speakers. (Vahalla XLR to ARC preamp) IC position doesnot change noise level.

ARC ph7 has some noise (buzz, hum). It is audible when no music is playing but when music is playing it is not an issue. What is strange is that when I change the position of the interconnect (single ended Cardas) connecting the phono to pre, the amplitude of the noise increase and decrease markedly. The PH7 is quieter at my friend's system in a dedicated circuit.

Noise is loudest with the ASR, amplitude varies with the positioning of the phono cable, interconnect. Interestingly, when I was leaning over the ASR phono, noise also decreased. Noise is present even when the tonearm is unplugged from the phono. Noise doesnot change with shunyata hydra in or out. I used to have a Hovland preamp which had a low level hum which completely went away when RF filter was installed by Hovland.

Guys, please advise me on how to reduce hum/buzz.

1) IS this due to RF from the powerlines (needs dedicated circuit ) or is it from RF in the air?

2) How can I shield RF in the air?

3) Is the RF picked up in the tonearm cable, phono stage or interconnect? I assume that the main culprit is the IC and possibly the phonostage because when tonearm cable is unplugged, noise is still there?

4) Is grounding issue involved?

thanks in advance
128x128glai
siddh
345 posts
 
Hi, I have experienced noise, more of a buzz from my phono cable. I found bending and subsequently supporting the cable in a certain location has minimized this very noticable obtrusion. This occurred with each and every phono cable I used. The FIM interconnect, which is extremely stiff was incapable of re-forming to eradicate the noise. The cable I now use, a flexible Elrod has been freed from the RF and/or EMI. Now the only added sounds are from the tubes of the Jadis preamp most noticeable during lp changes.

You may need to try relocating your phono stage, turntable motor, or cables. Good luck.
markd51
763 posts
 
You mention that even when the Cable is unplugged from the Tonearm, that noise/hum still exists? I gather you mean that no cable at all is going to any phono stage, yet you still get hum/noise?

If so, then that seems to eliminate the Phono Cable.

This problem seems to exist for some no matter how much they invest in a phono stage and/or Cables. One of my good friends (recently deceased) using a Clearudio Master Reference Table, Lyra Titan Cartridge could not get away from RFI/EMI until he bought a Battery Powered Phono Stage (The Sutherland PhD)

On his recommendations, I bought the PhD Phono myself, and while perhaps not the very last word in sonics compared to some other class-a rated Stages (well some say this, others don't), one thing I'll say about my PhD that it is absolutely dead quiet, even with a .35mv Benz Ruby 3, and running at 60db gain.

Don't know if line conditioner would help any of these phono stages you've tried, but I reckon at this point one would be willing to try anything to get away from this malady. I'm almost getting the impression that your difficulties lie with your electric service, rather than an airborne problem. Really hope you get this solved. Mark
dcstep
1,518 posts
 
Noise really ruins my enjoyment of analog (or any media). That's one reason I use a use a high output, 2.5MHz MC cartridge, like my Sumiko Blackbird.

Maybe there's a small tradeoff of resolution vs. noise, but I fall on the side of low noise.

Dave
glai's avatar
glai OP
446 posts
 
The noise is louder with phono cable plugged into the ASR and quieter without the phono input plugged in at all. However, there is still noise with the phonostage connected to the preamp. I tried orienting the IC differently and did result in marked decrease in noise (awkward equip position_. Would this indicate RF is in the air?

The ASR is battery powered. Why are some phono more sensitive to RF than others, are there RF filters or shileding available?
markd51
763 posts
 
Unsure if those little Ferrite RFI Filters that clip onto an IC would be of help?

One thing you could possibly try, is connecting a ground wire from the Chassis of the Phono Stage to Pre, or even perhaps too, a ground wire from Pre to Main Amp?

The only other things that come to mind here, is trying different Interconnects, but you might have tried this already? That, and perhaps another Pre-Amp? Can someone borrow you one to try?

I'm certainly no electronics guru, and I'm just drawing straws here, but the only logical answers I have is to go through every component associated with, and go through the process of elimination. Mark
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