Sony PS-X7 - Scraping Platter Problem

[Classichifi]

I have a problem with my vintage Sony PS-X7 direct drive turntable. It was working fine but since it had never been serviced, I decided to dismantle and re-lubricate the motor. After carefully putting it back together and testing it, I found that there is a slight scraping sound coming from the platter (about once every revolution). I cannot see where it is scraping and I'm sure I have not made any mistakes when putting back together! I have checked all the obvious causes.

Can anyone with experience of this deck offer and help or suggestions?

 

[flapland]

Never seen or taken apart one of these but wonder if its something daft like a washer on the wrong side of hole making the spindle sit lower than it should. Also check nothing left behind under the platter which has got stuck and catches on the platter.

Only other thing I can think of is it is similar to an issue I had on a B&O turntable where the lightweight platter had a metal ring fixed under outside edge. This came unstuck in one point and would catch occasionally. Eventually got the superglue out on that.

 

[russ abbott - royds broth]

Afraid i can't help,but forgot i have one in the loft.

 

[Classichifi]

Thanks for the replies. I have now managed to fix it by very, very slightly re-aligning the sensor that reads the signal recorded on the magnetic band that runs around the platter (this is part of the quartz locked speed control system and a similar arrangement is used on many Sony direct drives of the late 1970's through to mid 1980's). The sensor is meant to sit < 1mm from the platter rim but not actually touch it (of course). The TT is now working fine and sounding great

 

[flapland]

Excellent stuff, how does it compare to the 1200.

 

[Classichifi]

Hi Flapland, it's better than a stock SL-1200MK2 but not as good overall as my modded SL-1200MK2. It does, however sound less clinical with a warmer, fuller delivery. The Techie has a more "mastertape" i.e. uncoloured sound. I occasionally switch over to the Sony when I fancy a more lyrical, slightly romantic sound. The PS-X7 still has the excellent grip, dynamics and speed stability that you only get from a good direct drive. I think it's an excellent turntable and with automatic operation too!

 

[flapland]

Sounds very interesting and something to consider if I get a DD scratch to itch. I had a JVC DD with a electro magnetic damped arm for a while but that was in a very different system to I have now so I can't really vouch for it.

Out of interest how much did you pay for the PS-X7.

 

[Classichifi]

Sounds very interesting and something to consider if I get a DD scratch to itch. I had a JVC DD with a electro magnetic damped arm for a while but that was in a very different system to I have now so I can't really vouch for it.Out of interest how much did you pay for the PS-X7.

I think I paid about 90 quid on eBay - A bargain I would say as it's in very good condition for age. The original gel filled rubber platter mat had become misshapen (they all go like that with age) so I replaced it with an acrylic Inspire Acri-Mat which looks good on the deck and is probably better sonically too.

 

[russ abbott - royds broth]

One i have has speed issues which is meant to be common.