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symon
03-02-2009, 19:12
Hello all,

I've discovered an intersting trick my NAD 5120 has developed. It is generating a static charge when it plays records. It's enough of a charge for it to discharge into my finger if I touch the rubber mat. And the spindle in the centre is also storing a charge, which gives a little tingle when touched a few times. Needless to say, this discharge is going back through the amp and crackling out of the speakers.

Does anyone know what is happening and how I can stop it?

YNWaN
04-02-2009, 00:37
Try placing a couple of bowls of water in your room and you should find that static charge is reduced. How effective your deck is at discharging static depends on the construction of the main bearing and whether it is earthed (the main bearing that is).

Haselsh1
04-02-2009, 09:20
Mmmm... I agree with YNWan. I bet your room is like most of us here, centrally heated and very dry with little ventilation...??? My Linn Basik is exactly the same. Lift off a vinyl record and it crackles like hell. The air in the room is just too dry and it's generating loads of static.

YNWaN
04-02-2009, 10:27
One thing though - I would be surprised if your record really was generating static whilst it plays; unless you use one of those 'dust bug' brushes that rest on the record during play. It's more likely that you charge the record by cleaning it or from yourself (depending on your shoes/carpet).

I meant to clarify that it was the dryness of the air that encouraged the development of static - sorry.

symon
04-02-2009, 19:44
One thing though - I would be surprised if your record really was generating static whilst it plays; unless you use one of those 'dust bug' brushes that rest on the record during play. It's more likely that you charge the record by cleaning it or from yourself (depending on your shoes/carpet).

I meant to clarify that it was the dryness of the air that encouraged the development of static - sorry.

No, I don't use a dust bug and I don't have carpetted floors in the room the deck is in. I have been playing brand new records on it, though. Could this be a source of the extra static?

As for placing bowls of water around the room - I need to convinvce the wife this is a good idea first, but I'm willing to give it a go.

Primalsea
04-02-2009, 20:03
Static is a pain and I was plagued with it for ages until I finally got rid of it.

This is what I done.

1 Got a hard(er) rubber matt. I found one that had 2 concentric raised rings so the record was only in contact with it at those 2 places. Avoid soft rubber matts.

2 Clean the deck often with a damp, not wet cloth.

3 Keep your records in anti static sleeves.

4 Static is created by rubbing 2 dry surfaces together, dont do this!

5 Clean your records with record cleaner or a mix of distilled or de-ionised water mixed with ethonol (can by ethonol from maplins) HMV do a good cleaner in a pump spray bottle for about £4. Use a Microfibre cloth (e Cloth) these are the best that I have found so far.

Once the record is clean spray a light coating of the cleaner on the record and leave it to dry naturally.


Hope this helps

YNWaN
04-02-2009, 20:17
No, I don't use a dust bug and I don't have carpetted floors in the room the deck is in. I have been playing brand new records on it, though. Could this be a source of the extra static?

As for placing bowls of water around the room - I need to convinvce the wife this is a good idea first, but I'm willing to give it a go.

Well, I'm not suggesting you decorate the room with bowls of water - just put a couple out of sight - behind the telly or something. Putting moisture back into the air often reduces static. As stated by another poster, the central heating dries the air out and this encourages the development of static (of course you could use the heating less - see how your wife fancies that idea).

Many (most) new records come with a significant static charge and can be very difficult to remove from the inner sleeve for this very reason.

P.S. I wouldn't use a rubber mat of any variety - nothing to do with static, I just think they sound cr*p.

symon
04-02-2009, 22:37
hehe - yes, I can see how that conversation would go seeing as it's snowing again. Bowls of water is the lesser of two evils.

So, the extra static could just be the new vinyl. I'll test some old vinyl tomorrow and see what happens.

And, perhaps this is not the place for this question, and forgive my ignorance, but what options are there other than a rubber mat? And why do they affect sound? (Didi I mention I know very little about hi-fi?)

And thanks for the tips on record cleaner. I had already begun wondering about how to clean records, and if they should be cleaned.

pentode10
04-02-2009, 22:38
Hi,
if this is a new phenomenon with your deck I would make sure that nothing has happened to the earth continuity.
This would obviosly be a big safety issue if for example there are two issues
occuring..

1. the static discharge is ( not going to earth as it should )

2. the tingling when touching the spindle ( more worrying as a possible mains leak not going to earth )

Sorry, don't mean to be alarmist but worth checking just in case..

Cheers
Andy.

symon
04-02-2009, 22:45
Hi,
if this is a new phenomenon with your deck I would make sure that nothing has happened to the earth continuity.
This would obviosly be a big safety issue if for example there are two issues
occuring..

1. the static discharge is ( not going to earth as it should )

2. the tingling when touching the spindle ( more worrying as a possible mains leak not going to earth )

Sorry, don't mean to be alarmist but worth checking just in case..

Cheers
Andy.


Thanks.

That was my initial thought (and fear of a sudden flying experience!)

How would I check that it is earthing properly?

Primalsea
04-02-2009, 22:50
P.S. I wouldn't use a rubber mat of any variety - nothing to do with static, I just think they sound cr*p.

Theres rubber mats and then theres rubber mats. I heard a few crap turntables once didn't mean that I thought they were all crap.

The problems with matts is that felt is thought to sound one of the best. It causes too much static though which is a real pain. Apparently felt mats absorb all audio frequencies more or less equally, making them quite netural.

Other matts tend not to do this so you just have to keep trying until you get something you like that doesn't cause static. Sometimes a mix of 2 or more mats can work.

I've been hunting for a pure carbon fibre matt as they are conductive, no static but haven't found one yet.

Earthing the spindle is a very good idea.

YNWaN
04-02-2009, 23:02
I take your point, but actually I have tried a lot of mats and made a lot of mats. I haven't tried all rubber mats by any means, but I have tried a number of soft ones and hard ones - I preferred the hard ones (particularly dislike the Silicone one).

The felt mat is a pretty good compromise in terms of sound (I agree that it may well exacerbate static) but is not my own choice.

I use a minimal contact mat in which small nibs of metal make contact with both the record label and the metal platter; the main bearing on my deck is also run to earth - I never experience issues with static.

pentode10
04-02-2009, 23:33
Thanks.

That was my initial thought (and fear of a sudden flying experience!)

How would I check that it is earthing properly?

Firstly you need to be satisfied that you have suficient electrical knowlege to do any work or tests safely.If in any doubt take your deck along to a proper sevice engineer for testing.

First switch off at the mains and remove the plug.
Then just open the plug and check all is well and the wiring is sound.

Try and obtain a continuity tester or a small electronics meter from most DIY stores.

Set the meter to low ohms range and connect one probe to the earth centre pin of the mains plug and the other probe to the metalwork on your deck including the spindle.

The meter should deflect right over to the right around 0 ohms or if using a circuit tester the lamp should illuminate.
If it doesn't the earth is open circuit and your deck should be sent for service.

If you feel happy you could open up the deck and check for lose wiring and make good any bad connections and then retest.

All this must be done with the mains dissconnected...

The only proviso to all of this is if your deck has a two core mains lead and as such should be double insulated. ( ie no earth connection )

It may be as well to check you mains delivery outlets ie power block 4 way etc in the same way. ( Dissconnected from the mains )

The only less likely possibility is your house wiring.
If you've had fuse blowing or light bulb failier for no apparent reason on a regular basis, have your wiring checked out ( especially the earth )

Hope this helps

Andy.

symon
04-02-2009, 23:39
Andy - thanks. That is very helpful.

My electrical knowledge is minimal. But, what you have laid out here gives me confidence to at least do the checks, even if I can't fix any problems!

Primalsea
05-02-2009, 08:01
I use a minimal contact mat in which small nibs of metal make contact with both the record label and the metal platter; the main bearing on my deck is also run to earth - I never experience issues with static.

To be fair most rubber mats are made as cheaply as possible. You can tell this because they smell or their surface is not uniform in colour, or both. The mat I use is of good quality but its probably the very small contact it has with the record thats the important part.

I've just had an idea:idea:

An industrial gasket supplier should be able to supply a 10" and 4" soft graphite ring gasket. These could be glued to a cork matt:confused:

YNWaN
05-02-2009, 10:26
Hmm...well, the graphite ring gasket idea is an interesting one - I will look into it. I have tried cork as a radial ring mat, and rubber, and acylic. I quite like cork as a mat material but still signifacntly less than the system I use now.

chris@panteg
08-02-2009, 19:31
I've been hunting for a pure carbon fibre matt as they are conductive, no static but haven't found one yet.

i have one ' had it for years never really used it until now, been experimenting with my SL1210 with rubber mat then carbon fibre mat on top ' interesting results so far.

greenhomeelectronics
14-03-2009, 16:44
Rather than a bowl of water go to your garden centre and find some pot plants that like to be well watered. Buy two or three of them as a present to your missus, make sure the pots match the colour of the room your hifi is in, make sure she reads the label withthe watering instructions. It might be a good idea to start an argument with her first otherwise she might get suspicious that you have started bringing flowers home. Not only will you have a chuffed missus, you will have sorted your static problem and will have someone to replenish the water supply while you enjoy the music.
That will be job done, that will.
Dave.

break-3
14-03-2009, 17:18
You can get proper humidifiers to put moisture into the air. At their simplest, they cost a few pounds and hang over your radiator - those are the ones I use.

Tony G
15-03-2009, 00:29
It is also possible to use the Milty ZeroStat pistol - not having air conditioning or central heating, static is rarely a problem for me but I have one of these and use it when a record raises the hairs on my arm - it does the job.
I am not personally in favour of antistatic products applied to the record surface no matter how effective they are - we don't like extra gunk in our grooves we don't.
A light brushing with a carbon fibre brush while the record turns prior to play can also help but often not.
Best to treat the static on the record before play to reduce attraction of airborne dust - this is where the Milty is good.
All the humidity related info is good, just wanted to add an option.