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Do you have an additional ground cable running from the RCA connection box on the Scout, to the ground screw on your phono Pre-amp? I know my Scout hums without this additional cable. Try grabbing the tone-arm head shell between two fingers when the table is on, and the phono channel is open. If the hum lessens, you've got a ground issue. |
I have a Michell Gyro Se table and had a hum and a buzz. Does your hum change with the volume settings? I tried just about everything to remove the hum/buzz. Finally changed the cables from arm to phono preamp from Kimber Hero to Harmonic Technology truth link, ran a grounding wire from arm to linestage pre, not the phono pre, and plugged the phono pre and the linestage into the same outlet. It worked. I have not been willing to risk going back to determine if it was one of the above or the combination that did the trick. Good luck i know how frustrating this issue can be. |
I listened to a record at my dealer's once on a VPI/Transfiguration/CJ/Soundsmith phono/Vandersteen system worth probably about $30,000 and the sound blew me away. But once the record ended the hum/hiss was equally shocking at the high volume level I was listening at. After that I simply assumed that hum/hiss is simply a part of the analog experience but usually doesn't get in the way of music that much. I certainly felt much better about my humble--in comparison--Scout/Soundsmith Aida cart and phono rig that was producing some hum/buzz when not playing.
That said, VPI recommends replacing the TT cables with the cheapest, well-shielded cables you can find, if there is excessive hum. I ran the Kimber Silverstreak initially from the tt to the phono stage and I replaced it with a pair of Radio Shack cables that were on sale for the whooping $1.30!!! And guess what? It actually decreased the hum! Son of the b...ch! I suggest you try that solution since it virtually costs nothing. |
Check to see if your TT or phono stage IC's are near a power cord. That will give you a hum even with excellent cables. Move your RCA's or XLR's around a bit to see. |
Some VPI's use unshielded cables from the back of the tone arm to the the interconnect box. If your cartridge is a high output, that means it is high impedance, and unsheilded wires are a big problem. (Not so with Low output MC;s - the low impedance system tends to inherently be insentive to AC fields) Also - Someone on this thread mentioned the possible use of UNSHIELDED RCA cables - NO - NO - NO. THeya re very correct. VERY WRONG to use such. You cannot use such for low level signals of ANY kind. Thats why cheap shielded cables helped.
SO.....
1) Get sheilded cables for your RCA's from table to Preamp if you are using flat unshielded cables.
2) Move ALL ac cables away from the rear of the VPI if the tone arm exit cable is unshileded (you can see colors instead of silver shield wire). IF YOU TOUCH THIS WIRE and the hum gets worse, THATS your problem. TO fix that:
3) Wind some VERY soft VERY THIN single strand copper wire (take it from an old AC cord or speaker wire)in a sort of tight spiral (with gaps) wrap around the UNSHIELDED tone arm wire with the loose, long end near the arm wire jack. THEN, do it again but wind the opposite direction. Again the free end should be near the jack. Twist the loose ends together. Connect them to the GROUND LUG on the VPI box. Of course run a ground from this lug to your preamp.
Hum gone.
Peter Ledermann/President/Soundsmith
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Peter,
Thank you so much for your input! It's greatly appreciated. I hope you're healthy and feeling great.
I'm using your Aida MI cart in Ebony on my Scout with your MMP3 phono stage and I love it. I too experienced some hum, but it decreased after I replaced my Kimber Sliver Streak with a cheap, well-shielded interconnect from Radio Shack from the Scout to the phono preamp. (I'm running the Silver Streak from the phono to my main amp now.) One question I have to clarify: how do you tell if the tonearm wire is unshielded? If you see just silver, it means it's unshielded, and if it has colors, that's the shielding, right? It appears my Scout has a silver wire with a colored wires twisted together. Would the copper wire trick help with the hum further? Thank you. |
If the lead out wire from the rear of the tone arm is twisted COLORED wires, its unsheilded. Then you need to do my trick with the copper wire to make it a bit shielded. If it is silver colored, it is shileded. Nothing to do. Our cartridges are six sided magnetic shielded, so they dont hum at all.
Bear in mind that cheap Radio Shack cables are likely NOT well shielded, so you may want to go for some reasonable cables. The STRESS here is on the word REASONABLE - Dont go nuts with cables. Good shileded cables are fine - leave some funds left to buy some shoes for the children with the money you save.
Your flat cable from your Soundsmith preamp can still creat some hum, so try routing it away from AC fields as you listen.... or replace it with shielded types.
You should NOT have any hum AT ALL with our cartridges if all is well with your cables....and the possible VPI mod.
Peter Ledermann/Soundsmith
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Great advice. Thank you Peter. |
VPI has its own cables...they probably work.... |
One other thing that troubled me - someone mentiond a setup including Soundsmith Cart and Soundsmith MM (MI) preamp, which would be either our MMP4 or MMP3; I have designed these low cost phono preamps to have an extremely good noise figure at 43dB of gain of about 78dB down at a minimum; the best vinyl is about 72dB down from 0; someone mentioned a "hiss" that was "normal for analog". This is incorrect; the noise floor of the record is always "louder" than the floor of the gear (mine and most other well designed preamps) by at least 6dB. So.....a system with very noticeable hiss has something very wrong....his can be casued by many things, including RF, a power amplifier oscillating at high frequency, and such.
A computer nearby radiating RF....lots of possibilities.
With a quiet phono preamp, there should always be very little (if any) noise with the arm cued up....at normal listening levels.
The only exceptions would include the wonderful transformerless MC tube preamp by my friend Jim Fosgate, in which he has managed to get enough tube gain WITHOUT transformers, at a very small sacrifice of increased noise. He hand built one for me after I sent him my Sussurro cartridge and MCP-2 preamp combo, which he liked very much, but said "I'm going to hand build you one of mine"......I have brought it to shows we have done....what a great sound it makes......
Peter Ledermann/Soundsmith |
Peter,
This is very interesting and I am intrigued by your statements based on my auditioning experience a few months ago at my local dealer. I listened to records on a system that consisted of the VPI HR-X turntable with the SDS, Transfiguration MC cartridge (don't remember which one but it retailed for $1500), your own Soundsmith MCP2 phono stage, Conrad Johnson pre and main amplification, and Vandersteen 5A speakers, plus Richard Gray power conditioning; I don't remember the cables.
The sound absolutely blew me away--the dynamics, clarity, energy, transients, soundstage, oomph, slam, you name it, it was all there. But when the music faded, the hiss coming from the speakers was almost equally amazing; I was shocked by just how much of it was being produced on this otherwise absolutely amazing gear.
Granted, the volume level was pretty high, but based on your comments, the hiss should not have been there. Considering the fact that the setup was top notch, what could have possibly been causing the high level of noise in your opinion? |
No clue, other than what was stated above....except, possibly, potentially very, very low output from the transfiguration (I didn;t look it up)...My Sussurro is .3mV; similar to a Denon 103 in output....BUT if the cart being used was .1 or less....Then the requirement of turing up the preamp following the MCP-2 would amplify the noise to some degree. The MCP-2 is a step up design; with 43 db gain following the transfomers. With VERY high listening levels on my Soundsmith system with the Sussurro, there is no noise from the listening position when cued up. You have to put your ear next to the speaker to hear any operational noise. Somehow your experience with this system doesn't add up....SOMETHING was wrong....
There should be little or no noise.
Peter Ledermann/Soundsmith |
