I've driven myself batty chasing down the same gremlins in the past. I DO know that basing your noise level "frame of reference" on what you hear when your pre-amp is set to "CD" when comparing phono noise levels is a recipe for total frustration. The fact that you are dealing with the low-level phono signal, AND have tubes in the circuit almost demands you learn to tune out some low-level noise as you do with vinyl surface noice and just "enjoy the music", as they say. Want to really frustrate yourself, though? Add a step up transformer to the mix, and then spend hours trying to find the position where it causes the least amount of added 'hum'. AAArrrgh!
My latest OCD phono fixation? The motor noise I can hear from my 'table between tracks in a quiet room. Can I hear it when the music is playing? Of course not. Does that stop me from obsessing over how to get rid of it? No way, Jose' - just the idea that it's there really bothers me.
Audiophilia nervosa.
I do look forward to the responses from some of the other, more knowledgable A-goners to the good question you've posed, and good luck. |
I have had hum/noise problems in the past and have reduced it by trying various grounding schemes. Yes, the noise is probably RF and EMI being picked up by cables which act as antennas. It sounds as if your equipment is at different ground potentials and the noise is not draining out to a true ground. So what you need to do is get some wires and try grounding chassis screws/grounding posts, etc to each other and to a known ground such as the grounding plug on an AC outlet. Recently I had this problem when I bought a new turntable and ended up grounding the turntable and phono stage together, and then to the ground on an AC outlet. I would avoid the use of cheater plugs (convert 3-prong to 2-prong plugs) to lift the ground, as you may create a dangerous electrical shock condition. |
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. |
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 |
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 |
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? |
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 |
I tried the grounding the phono and preamp wiht no improvement. Tried Valhalla, Cardas GOld Ref and Signal Cable, no significant difference there. |
IYou said it decreased when you re-oriented the IC. s the IC running parallel to any AC cables, or near any transformers or power supplys in your equipment? |
Be certain to use balanced cable with your balanced equipment.Have proper grounding.Also, use of noise reduction equipment (distribution/ power conditioning) can also be very helpful.
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try plugging into different wall outlets. ...I've noticed big differences in performance with an outlet on the other side of the room. Go figure. I use balanced...dead quiet, even with the volume control all up.
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Glai, give all your equipment the same ground by plugging everything into the same power strip. The only exception I make is for large power amps which I like to have dedicated lines for. If you have a lot of money a Shunyata is fine. Next make sure your tonearm ground is separate from the turntables motor ground. Motor ground should go to the power strip. Tonearm ground to the phono preamp. You may need to check this with a meter. See what the noise is like with and without turntable and tonearm grounds. Next except for the phono amp and preamp unplug each piece of equipment one at a time to see if the noise disappears. Is it a noisy tube? You have to get super low noise versions of first your phono amp then Preamp tubes to figure this out. I get mine from RAM Labs (The Tube Store) Next is the noise coming from within your house or outside your house. Run around your house unplugging stuff. Then you have to unplug your neighbors or put your stuff on an isolation transformer. Are you crazy yet? I suppose I am a very lucky guy. When I built my house the electric company forced me into buying my own power isolation Transformer, one of those big green things they park on your lawn that your wife spends the rest of your money on trying to hide. I put a three phase converter in the house to power the shop and they were worried I'd drive the rest of the block crazy. Funny thing is I can turn on the entire shop and the Hi Fi stays dead quiet. Oh yes there is a little noise through the phono amp if you turn the volume all the way up. This is normal. |
Remove the tube preamp covers and hover your hand close to the tubes. You may be able to inject noise into the amplifier this way if something is not right. See if you can home in on a sensitive tube and change it out for a known quiet tube.
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This really sounds like a bad ground. Since the hum is worse with the arm plugged in, my bet is on the ground connection has failed.
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