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

To anyone interested, Home Depot has these vibration pads in store
Husky Heavy-Duty Vibration Pad for Air Compressors-HDA12200 - The Home Depot

I’m going to take a hard pass on these though. They STINK bad. I think I’ll stick with hockey pucks underneath the block.

And if hockey puck, 3” butcher block, isonoe glass boots, isonoe feet don’t kill the vibrations, then to hell with it.

 

Imagine having your friends over for a listen and suddenly one asks like: "damn... whats that smell?!"
And you be like: "wanna sniff at my vibration pads?"

 

Even if you don't need to for leveling, I suggest you try backing the Isonoe feet out a bit so the foam stand off is not squished up against the bottom of the TT. You may or may not notice a difference.

 

I’ll try that. I’ve been wondering how far the feet need to be screwed in since the manual is a bit unclear, but I never really experimented with it.

 

Thats a good idea. I could actually mount the old Technics feet to the block

 

And you tried loosening the headshell slightly and moving it around to find a noise free sweet spot? If my headshell is too tight, I get noise

 

I did try that though only yesterday so a good tip! It doesn't effect it though. I had an older Rotel deck with the exact same headshell and cartridge and that was most definitely effected by moving the headshell around.
I'm worrying about noise I can only hear through my sub when it's loud essentially but it does bother me lol

 

What kind of noise? Electrical or acoustics? Because the headshell and the tonearm must be "one thing" together for vibrations.

Maybe you hear "electrical" noise and then maybe is good to clean the contacts between tonearm and headshell.

Check that

 

@Robert Godridge, I took at look at your noise recording in an audio analyzer program. The frequency is 50hz and it's roughly -75dB.

Where are you located? I'm wondering if this is just electrical noise.

 

I'm in the uk so yes that is electrical noise. Isn't that quite high/loud, though? I can definitely hear it. It lessens when I touch the ground screw and again when I unplug the power, which makes sense if it's 50hz mains noise.

 

I don't know what level you have your digital recording set at but I had to turn the volume up extremely loud to hear anything on a set of IEMs.

Do you still hear this noise when records are playing?

 

I must admit, while I thought I was hearing it I just listened to the runouts of several records and a 25 second long blank groove on a mint classical lp and only when the sub is cranked past listening levels can I hear it,

My worry, though, is that I'm doing a lot of 78rpm work with this turntable and restorations, so I really need it as quiet as it can be!

 

There are various needledrop tip threads on here...maybe someone has a technique to remove the 50hz noise after the digital recording is made?

 

So as a sort of summery, this isn't out of the ordinery for this deck? I'm not sure what's normal and would really like to minimise this at the sauce, I could likely do a digital cleanup but would a hum like that not obscure some detail?

 

I don't think it is normal in your case since it seems like you have a grounding problem. You'll have to check the needledrop threads for more info.

 

I think it's normal, to have a 50Hz hum at -75dB in an analog circuit. I mean, it's -75dB... what would you expect? complete silence isn't a realistic goal.
But I think you're right that it's related to grounding (or the lack of), which is inevitable - up to a certain point.

 

I will ask on the "post your needle drops" thread and try to get a sense of how normal that amount of mains hum is, but I will replace the ground wire, possibly the power cable if it will do much good and the interconnects, perhaps at -75db it is kind of academic rather than a problem that gets in the way of my enjoyment of records but I'm picky!

 

If you touch your finger to the wire and the hum goes away that means the grounding is not working. I think it is unlikely that the ground wire is broken but you can try the new one. I would not bother replacing the power cable. What I would do is assess your equipment placement if this bothers you. When you start putting pieces of gear next to each other anything with a power supply transformer of any sort can cause noise. I would also get your outlets tested and the extensions checked.

 

Well.. If you're planning to archive 78s, I can see why you'd want perfection - once recorded, it's fixed forever...
But it has to be good enough at some point, since perfection doesn't exist with mechanical mediums such as vinyl/shellac.
Looking up what amount of background noise/hum is reasonable might be a better way to start and then set that as a goal to work towards.
Otherwise, that "chase" for perfection can take forever.

 

Weird, I actually tend to associate silver equipment with the ‘80s, for some reason...

At this point, I’m in a position where stuff I already have is black, so I keep buying things that are black, because I don’t really like a mixture of silver and black (which the 1200s themselves are, having the black base).

I think an all-silver setup can look real nice, though.

 

Try removing the headshell and I think the slight hum will go. Otherwise it is an earth problem. I think these decks do pick up a bit more noise than other usually fixed arm designs. I've said before I get a slight lower mid hum with the 1200G that I don't get with my other deck but it's so low you have to be close to the speaker to notice and I'm sure it's not audible with the stylus in the groove. A specialist external arm cable did help a bit. Possible RFI pick up through arm wires or headshell/ connectors? You will always get white noise hiss with any phono stage and that doesn't affect the music. If the hum is not significantly above the level of hiss it should not be a worry. Loud hum is something else such as an earth loop.

 

I've spent most of today trying to work out what is normal in dbs and had absolutely no luck other than people bragging about how "silent" their systems are, so this is what I'm trying to get a sense of, -75db mains noise normal or not?

 

I think -75 dB is good enough, since the maximum possible dynamic range of polyvinylchloride is about 70dB.
This is probably lower for shellac.

Comparison of analog and digital recording - Wikipedia

 

Why do you think it's mains noise? If you unplug the deck does the hum go away? (sure you tried this). If not it is coming from anything between cartridge to interconnects. Also could be an incompatible earth regime on the amp you are connecting to. Get someone to make up a second earth wire connected to the earth pin of a plug and run from amp/phono stage earth post to a power socket, (any difference?).

 

I mean to try the earth thing if I can get someone to do that.

It alters when I touch the ground screw, not the wire but the screw

having the wire unplugged or not makes no difference from either of both ends.

it shows up as 50hz visually aparrently.