The Technics SL-1200 GAE/G/GR general questions thread

I can see where you're coming from, but I am using the gr completely in stock form other than cartridge, so it is likely that someone at some point will get it and have the same issues that I'm having, isn't it?
Let's say someone buys one and gets it set up tomorrow, having read reviews that say it's "dead quiet" etc and they have the issues I'm having, they can know it isn't just them.
and I for one wouldn't like to lose your contributions to this thread over my admittedly long and winding issue, but do concidder the fact that it's in stock form and all that emplies like stock interconnects, is anyone else even using them?

 

Now this is exactly what a public thread like this one is meant for.

Fair point, now that it seems like it's not specifically a Technics design issue but more like general phono signal issue.
Still useful to talk with people that have the same or very similar turntable for the right point of reference (my turntable also has a very low 50Hz hum, but I think it's even lower than that of @Robert Godridge - mine can be considered as being "dead quiet")

 

New cables one day will tell all of us a bit more about this issue, but they'll have to wait until my new mixing desk/amp is done,
I do think though that, since I am using this entirely in it's stock form, someone may read this in the future who is having some 50hz noise and know they're not the only one.
It's also true that while it isn't silent it's reasonably quiet!

 

I'd say you can't rule out that it's your mixer that's picking up the noise, especially given this seems to be a bit of a custom set-up. But if you'd like recommendations for a well-shielded cable that has very low capacitance, I always recommend the Blue Jeans Cable LC-1, which is what I use. It's very reasonably priced. Not the most exotic cable, not by far, but it gets the job done. Stereo Cables at Blue Jeans Cable

 

As a quick test, you might be able to wrap some tinfoil around the cable (yes, tinfoil jokes haha) and see if the hum gets less loud.
But maybe a basic drawing/diagram of blocks to make the others see how your stuff is connected might also come in useful.

 

I will definitely concidder those cables.
The noise file was made with the mixer off and unplugged, so what folks are telling me they can see doesn't have anything to do with the mixer.

 

I'm totally blind so diagrams aren't something I can do. I can get someone to take pictures but It's all going to have to be reconfiggured with the new mixing desk first so may as well wait til then, I will keep all here informed and probably get new phono cables. I'll try the tinfoil trick didn't think of that!

 

I thought the Low capacitance of blue jeans was unshielded and had a low capacitance (partly) because of that?
I think Inakustik has an all in one phono cable where the shield actually is also the ground wire, making it similar to the grounded tonearm tube with wires running through it.

Ah yes, I forgot about that...

 

I think it was you who pointed out the noise was at something like -60db and quite quiet in your estimation. Yours is still quieter, so are you using one of the new technics decks too?

 

I have the SL-1200G, so it's tonearm assembly is the same in many ways, except that the tonearm tube is magnesium, but that shouldn't make an electrical difference.

I used a fancy AudioQuest Big Sur RCA cable (0.6 meter) in the past, but found out that a cheap ProCab Reference RCA (1 meter) provided a lower noisefloor hehe
Never used the stock phono cable though...

 

Interesting. Do you have any idea how much quieter yours is than mine? yeah I know this is no exact science etc I'm just trying to get an idea of what a phono cable upgrade might bring, then until new mixing desk is here or I get better cables I'll shut up about it lol
I'm not sure I'm remembering -60db correctly but I think so.

 

Well... I can’t measure it anymore, because it’s below the noisefloor of my phono preamp now.
It’s below -68dB if I remember it correctly.

 

Thanks, that's a fair improvement, so when I have a different and hopefully better phono cable I can expect that level of audible upgrade.

 

The point is with the new switch mode PS cartridges do not pick up hum as with the old Mk II PS. Not a big issue with MM but certainly with MC. I had that issue with the Pioneer PLX 1000.I think Robert confirmed with no power there was still hum from the phono cables. So it's the either headshell or int/ext arm cables picking up something or not earthing properly.

 

Well... IF it’s the phono cable and not some sort of ground loop.
The ground from the power cable is via the turntable case connected to the phono ground.
Individually connecting your phono preamp to the ground of the power outlet can solve (or cause) grounding issues too.
Preferably, all the phono related stuff is connected to the same powerstrip.

I can really recommend the tinfoil wrapping as a quick test to see if it could help; randomly buying cables is often a waste of money.

 

Yes all my phono stuff is on the same outlet.
There is most definitely a turntable grounding issue, as outlined above, and I'm not the only one having it. It makes no difference if the ground wire is plugged in or not, but touching the grounding screw under the deck makes a difference. I contributed to this thread on VE but I'm definitely not the only one with a grounding problem.
Technics Sl-1200GR grounding- Vinyl Engine

There's hiss then there's 50hz noise and I think the hiss is likely to be better with improved cables, that's what I'm thinking rite now anyway. Another thing is that the screw being touched makes a difference even when the deck's unplugged!
and I thought I was about to shut up, lol

 

That sounds like when you’re touching it, your body functions as a path to ground.
I don’t know if your preamp has a grounded power cable... but if it has a wall wart or some other power connection without ground, you should try mounting a wire from the case of your preamp to the power outlet ground.

Edit: or, ideally a continuity test between the ground cable and the ground pin on the turntable powercable to see if there’s a connection.

 

Well since a good friend is finishing off my soon to be preamp I will ask him if it can have a grounded power cable, thank you for the great suggestion!
This is why it's all sort of in limbo at the moment but I'm taking notes!

 

I tried to edit my last post to include this but it didn't work


For that recording of the noise my turntable was grounded to a usb phono preamp, and so I think that says that since I'm getting that with different equipment it could be the inner grounding of the turntable at fault.
What would really help would be if someone with the stock cables can let us know what they're hearing or make a recording of it etc.

 

Ah... USB ground can introduce noise too. If it has a USB ground lift switch, you should activate it.

As a last resort, you can test the ground of power outlet.
Sometimes goofy electricians connect the ground to the neutral...
In North America it’s normal to connect the ground to neutral in the main breaker box, but this shouldn’t be the case for the rest of the world.

 

What happens with the GR completely unplugged from everything?

(power cord from outlet and rca cable & ground wire from preamp)

 

The hiss is the phono stage and normal and according to signal to noise ratio. Better phono stages have less hiss. The 50hz is noise due to cable or earthing. Changing cables won't remove the hiss but might reduce or eliminate the 50hz noise. Try running an extra earth cable from TT earth point to a 3 pin plug. Need to make up a wire with 3 pin UK plug one end and spade connector on other. Obviously you will have to get someone to do it for you. You will either reduce the hum or increase it depending on what is connected. If a component is designed to not have an earth (internally earthed , Class 2) you can't add an earth to the mains connection.

I did a google on the problem which brought me back to beginning of the thread. Hum was solved or reduced by adjusting headshell tightness. Other thing may be to upgrade the headshell wires to something better insulated. It's all suck it and see. I still have a slight hum with my G (ear close to speakers) so it could be inherent to some extent with all these TT designs dependent on the phono stage or amp you are using. Have tried different headshells without much difference. My orbe/SME connected to same stage has pure hiss. Hiss only is good and nothing to worry about.

 

SME pay better attention to RFI rejection and grounding connections than some other companies do.
The armtube has a proper ground cable connection point.

Which phono stage do you have?

 

Musical Fidelity M6 Vinyl.

 

Hum is audible from my brand new SL-1210GAE ONLY if I crank the volume of my 200w amp past 50% and only if I put my ear very close to my 102db efficient speakers. ..I would NOT hear the noise at my listening position and definitely not over the groove noise of the record. And at 50% volume, the output would be deafening if I dropped the needle and played music.

I will say, I do have to make sure my overhead lights, which have a dimmer, are off, plus the plasma TV m0unted 7" from my 1210 is off. ..But even with all of that left on, the hum/his isn't audible from the sofa and still wayyyy below the groove noise of the record. ..No one could hear it while playing a record.

Robert G., is this noise louder than the groove noise?