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Static and Turntable

R

Robby

pfm Member
I wonder if anyone can assist with a problem that I have noticed recently.

I have a Rega P3 (latest version) for around 4 months and love the music it produces.

I have noticed though that recently that music has started to distort halfway through playing a record. When I raise the tonearm and lower it again it sounds better. When the tonearm is raised though there is some severe crackling through the speakers.

I assume that it was static build up and have wet cleaned my records to try and alleviate the issue but to no avail. Whilst the distortion when playing is virtually gone, when I lift the tonearm the crackling starts again for a minute or so. I then change the record and go through the same process.

This happens with new and older records.

What could be causing the noise? If it is a build up of static it seems unusual to me and something I have not had an issue with to such an extent before in the 30 or so years of owning turntables.

Any suggestions?
 
It could be static. Placing the back of your hand very close to the record, are the hairs on your fingers (assuming you have them, hairs, not fingers) drawn to the record surface? Are the records stored in an unusually dry environment?

I guess it could also be faulty arm wiring. Do you get the crackle without a record on the turntable and moving the arm around?
 
Find an antistatic turntable mat.
Goldring used to do them, but I think no longer.
Did you get a new carpet to cause the problem?
 
I'm a firm believer in grounding a turntable's main bearing, i.e. ensuring there is electrical continuity between the platter spindle and mains earth and therefore a path where any static charge present in the vinyl can safely dissipate. On most turntables this is either done by default via a grounded metal chassis or can be achieved simply by running a thin wire from the metal main bearing housing to the amp/phono stage earth terminal. On a Rega it would likely be a bit more complex due to the plastic sub-platter, though I'd still expect a proper path to earth would help here, i.e. do try running a little wire taped to the metal bearing housing to the preamp earth and see if that helps. What you really don't want is for a statically charged record to discharge via the cartridge, that is where the crackle and pop comes from.
 
Static electricity will find a path to earth even across an insulator (the platter and the record on a Rega are both insulators after all!). Providing a clear path to earth from the bearing should provide a preferential path, rather than through the cartridge.

Distortion that disappears by raising the arm could also be an accumulation of fluff on the stylus. So it could be a combination of static and fluff.
 
Tony L said:
I'm a firm believer in grounding a turntable's main bearing, i.e. ensuring there is electrical continuity between the platter spindle and mains earth and therefore a path where any static charge present in the vinyl can safely dissipate. On most turntables this is either done by default via a grounded metal chassis or can be achieved simply by running a thin wire from the metal main bearing housing to the amp/phono stage earth terminal. On a Rega it would likely be a bit more complex due to the plastic sub-platter, though I'd still expect a proper path to earth would help here, i.e. do try running a little wire taped to the metal bearing housing to the preamp earth and see if that helps. What you really don't want is for a statically charged record to discharge via the cartridge, that is where the crackle and pop comes from.
Click to expand...

I think I've just had a Eureka moment.

My TT has an earth wire from the bearing as well as the arm / cart. I've an issue with one or two static pops when putting on or taking off record; other than that playback is fine. Looking back, this problem may have started around the time I switched from the MM phono input on my integrated amp, to a standalone MC phono stage (Arkless). I'm thinking that either;
a) the earth wires from the TT may still be connected to the integrated amp rather than the phono stage (Question; could this be a cause? Does it matter which amplifier the earth wire is grounded to?), or
b) the earth wire from the bearing is not connected properly.

I'm at work at the moment so will need to check when I get home.
 
Some cheaper phono stages use wall-wart PSUs that don't have a mains earth, i.e. the earth pin on the wall wart is plastic. I know the Arkless stage is a tweaked Cambridge Audio unit, and I know that uses a wall-wart, but I can't recall if it has an earth. If not you are relying on grounding via the arm cable & interconnects which is not ideal IMO. It is times like these where a multimeter with a continuity setting is a very useful thing to have knocking about. My turntable has a metal centre spindle and I just make sure I get continuity between that and mains earth. I have absolutely no issue with static whatsoever, though I certainly did back when I had a NAS spacedeck which is when I figured out running a dedicated wire from the bearing housing to earth was a very useful thing to do. It fixed it completely.
 
Tony L said:
Some cheaper phono stages use wall-wart PSUs that don't have a mains earth, i.e. the earth pin on the wall wart is plastic. I know the Arkless stage is a tweaked Cambridge Audio unit, and I know that uses a wall-wart, but I can't recall if it has an earth. If not you are relying on grounding via the arm cable & interconnects which is not ideal IMO. It is times like these where a multimeter with a continuity setting is a very useful thing to have knocking about. My turntable has a metal centre spindle and I just make sure I get continuity between that and mains earth. I have absolutely no issue with static whatsoever, though I certainly did back when I had a NAS spacedeck which is when I figured out running a dedicated wire from the bearing housing to earth was a very useful thing to do. It fixed it completely.
Click to expand...


Thanks Tony,
I had to replace the Cambridge wall wart with a new one from Maplins; I'll check the earth pin tonight.

Ian
 
I don't usually get much in the way of static problems. Metal TT, use of disc preener, etc, etc, seem fine here usually.

I was prompted to wonder if something like a small bottle cap upturned and with a wet wad of kitchen towel in it might help to make the air over the disc damper and cure such problems. That said, I always have the cover on my deck down when playing a disc, and maybe these days people often don't do that?
 
Tony, the main bearing on my deck is connected to mains earth in the way you describe. However, with the bearing shaft supported as I do there isn't actually any metal to metal contact between the platter/bearing shaft and mains earth - I still don't get any issues with static and never have done.
 
Spiderous said:
Thanks Tony,
I had to replace the Cambridge wall wart with a new one from Maplins; I'll check the earth pin tonight.

Ian
Click to expand...

Boom!

Plastic earth pin on the wall wart for the phono stage, so transfer the earth leads back to the integrated amp, static pops gone.

Thanks Tony.

Ian
 
my TT (well tempered) doesn't have a groundable main bearing ... i'm wondering if a length of solder wick (braided copper) hanging down to touch the record surface - wired back to electrical mains ground might do the trick?
 
Holy shit!!! You're half way to a Wimshurst Machine doing that!

I suffer a lot from dust here, but not that much from static.

One simple precaution I take:

I usually give all records a quick wipe with a Goldring 'Super Exstatic' carbon fibre brush, before playing. I hold it lightly to the entire width of the playing surface for a few revolutions then slowly draw it outwards to the edge to prevent a 'dust line' forming where it is lifted. While doing this, I'm holding the metal brush grip in one hand and have the other hand on an earthed metal component, to dump any static to earth. Works for me.
It's easy wih my present Gyrodec which is pretty much all metal.. and earthed. With my former LP12, I used to touch an earthed metal amp case, or the arm pillar of my Ittok.

Interestingly.. ( to me..) the very first couple of LPs I bought back around 1962 ( or 55 years ago in old money) are now totally static free whatever...

Dunno what's happening.. but I think we should be told..
 
If you have a RCM machine I find a clean cures all the static

I never have a problem now

I find new records have quite a bit of static build up and once cleaned all gone.
 
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