SUT and ground loop hum

[Wakefield Turntables]

Man this is really frustrating I've just got a new SUT to try out and all I get is a bloody ground loop hum, any ideas where this could be coming from??? I have no issues with loop hum when the SUT isn't in the chain? :scratch:

[Jonboy]

Have you tried running it without the earth attached in the plug?

[hifi_dave]

Move it away from anything with mains on it.

Earth it via a separate wire to the amp earth terminal or chassis.

If all else fails, start removing earths.

[Marco]

Man this is really frustrating I've just got a new SUT to try out and all I get is a bloody ground loop hum, any ideas where this could be coming from??? I have no issues with loop hum when the SUT isn't in the chain? :scratch:

See my reply to you in the Yannis cable thread, daftee! ;)

Marco.

[Wakefield Turntables]

noted, will try tomorrow. :eyebrows:

[Wakefield Turntables]

now sorted! Amazing what a piece of 1mm solid core copper wire can do. :D I now have fantastic quiet background when listening.

[Marco]

Told ya! Should sound better, too... :)

Marco.

[Wakefield Turntables]

yeah alright, i'm a daftee, its official.

[Marco]

So, how's it all sounding, daftee-chops? That's the most important thing!

Marco.

[Wakefield Turntables]

Stunning! This may give you some idea of the level of detail I can now hear. I own a copy of the Somewhere in Time album by Iron Maiden. I've owned this for 25+ years. For the 1st time ever I managed to hear a small amount of echo on Bruce Dickinsons voice at the beginning of Powerslave, I've never heard that before; I also noticed a bum note that I'd never heard before from Steve Harris's bass. I've had to turn the volume DOWN because the SUT has made things louder but the detail is vastly improved. Instruments now seem to have greater seperation, vocals appear a tad more pushed into the back of the soundstage whilst guitars and drums appear in the foreground. Lots of things are happening. I intend to do a full report in 2-3 weeks when things have settled in. You've got to remember that I've had the PCB recapped with new capacitors, so I have no idea what effects these will have as no-one has had this done before. It's exciting times Marco. :cool:

[Marco]

Excellent stuff, dude.

It's good that you're hearing musical improvements, as opposed to just hi-fi ones, which is a sure sign that your upgrades are reaping real improvements. What you're describing are traits that I recognise in the ST-80SE. It's a superb SUT :)

Did you manage to get hold of Simon? If you don't pursue it, you'll miss out! ;)

Marco.

[Wakefield Turntables]

Today, as soon as 930 comes I will call him and report back, sir :eyebrows:

[Marco]

Excellent - I look forward to it :)

Marco.

[Wakefield Turntables]

Called, just waiting for a quote :)

[MartinT]

Really pleased it's working out for you, Andy.

Sent from my HTC using Board Express

[Marco]

Called, just waiting for a quote

I presume you mentioned that you know me? :)

Marco.

[Wakefield Turntables]

Yes of course.

[Wakefield Turntables]

Really pleased it's working out for you, Andy.

Sent from my HTC using Board Express

Thanks very much :cool:

[Marco]

Called, just waiting for a quote :)

Did you get one?

Marco.

[Wakefield Turntables]

Yes. I've sent you a PM with regards how much he quoted.

[Marco]

No PM has arrived, daftee....

[Edit: soz, just has now!}

Marco.

[Wakefield Turntables]

just sent, bloody 'ell gimme a minute :lol:

[Marco]

Lol - you said you'd sent it before you'd actually done it, daftee! :D

Anyway, you have a reply.

Marco.

[MikeMusic]

See my reply to you in the Yannis cable thread, daftee! ;)

Marco.
Marco (anyone)
Can I have a pointer please ?

I could have red this already and not twigged
:rolleyes:

[Marco]

A pointer to what, daftee? :)

Marco.

[Wakefield Turntables]

Marco (anyone)
Can I have a pointer please ?

I could have red this already and not twigged
:rolleyes:

This was part of a conversation bewteen me and marco :scratch:

[Marco]

Indeed...

Marco.

[MikeMusic]

A pointer to what, daftee? :)

Marco.

I think/hope a way to get rid of the hum Mark had and I still have

>Originally Posted by REXTON
Man this is really frustrating I've just got a new SUT to try out and all I get is a bloody ground loop hum, any ideas where this could be coming from??? I have no issues with loop hum when the SUT isn't in the chain?

>See my reply to you in the Yannis cable thread, daftee!

It occurred to me today that although the hum is not bad it could be causing degradation in the sound

[MartinT]

Mike - if you have any hum then it's indication that the sound is being degraded as your earthing is not right. When you get rid of it, you will hear for yourself.

[MikeMusic]

Mike - if you have any hum then it's indication that the sound is being degraded as your earthing is not right. When you get rid of it, you will hear for yourself.

I remembered I was going to look at the Aro and Linn for earthing as per your answer - as I was going to bed last night......
Maybe tonight once I sort my bike chain

[MartinT]

once I sort my bike chain

No, I think that's over the top for an earth wire.

[Wakefield Turntables]

Really pleased it's working out for you, Andy.

Sent from my HTC using Board Express

+1 for degradation of sonny, if your ears are old enough you can always a slight hum in the background of the music. No matter how much you try and avoid it it's always there. Mines ok now thanks to marcos tip. Best luck mate with sorting out the hum.

[MikeMusic]

No, I think that's over the top for an earth wire.
I try it !
:)

[MikeMusic]

+1 for degradation of sonny, if your ears are old enough you can always a slight hum in the background of the music. No matter how much you try and avoid it it's always there. Mines ok now thanks to marcos tip. Best luck mate with sorting out the hum.

What did you do ?

Make it nice and easy for me !

[Wakefield Turntables]

Well my problem might be different to yours :scratch: but put simply I didn't earth the sut. All you need is a piece of copper wire (possibly shielded if you can get some) and bind it to the back of the sut binding post and the other half to your phono stage or amps binding post if its has one. I noticed that you might have a tonearm problem. I had a similar issue with my technoarm and sent it to j7 where he managed to find a problem where the intrinsic wiring had become mangled together, this may help :cool:

Good luck

A

[Marco]

Hi Mike,

SUTs must be grounded in some way, which is why you have hum.

Just run an earth lead (using some suitable wire) between the earthing post at the back of the SUT (the gold plated terminal in the middle of the input and output sockets) and, say, the chassis of your preamp/phono stage.

A good way of connecting the latter is to screw the bare wire (or fit one of those little round tags onto the bare wire of the earth lead, which has the same diameter as that of the screw used) down in between one of the screws on the chassis of your preamp/phono stage, so that it the wire is trapped underneath. This is especially useful if the earth post on your preamp is already crowded!

Do that (or something similar) and your hum should go :)

Marco.

[MikeMusic]

Well my problem might be different to yours :scratch: but put simply I didn't earth the sut. All you need is a piece of copper wire (possibly shielded if you can get some) and bind it to the back of the sut binding post and the other half to your phono stage or amps binding post if its has one. I noticed that you might have a tonearm problem. I had a similar issue with my technoarm and sent it to j7 where he managed to find a problem where the intrinsic wiring had become mangled together, this may help :cool:

Good luck
A
Thanks
I had terrible hum when I earthed the SUT direct from the LP12.
Hum much less earthing the LP12 direct to the 82 along with the earth braid on the Yannis lead from the SUT
Could well be I need an earth from the SUT to the rather crowded and not easy to use earth post on the 82

[MikeMusic]

Hi Mike,

SUTs must be grounded in some way, which is why you have hum.

Just run an earth lead (using some suitable wire) between the earthing post at the back of the SUT (the gold plated terminal in the middle of the input and output sockets) and, say, the chassis of your preamp/phono stage.

A good way of connecting the latter is to screw the bare wire (or fit one of those little round tags onto the bare wire of the earth lead, which has the same diameter as that of the screw used) down in between one of the screws on the chassis of your preamp/phono stage, so that it the wire is trapped underneath.

Do that (or something similar) and your hum should go :)

Marco.

Thanks Marco
That is no.2 job tonight then. Must get my bike chain back on first !
:)
No.3 will be to listen to Ry Cooder on CDP and newly earthed LP

[krugdoktor]

Yannis Tome of back-promo fame sent a diagramm when I ordered my phono cable. Maybe this helps. I use the first option.

[MartinT]

I use the third model, which is star earthing to the central (preamp) earth post.

[MikeMusic]

Yannis Tome of back-promo fame sent a diagramm when I ordered my phono cable. Maybe this helps. I use the first option.

Thanks Michael
Gives me some options if Plan A doesn't work