Sony PS-6750 - a journey to the dark side

[ian]

I picked this up today from a seller on the Wam.  Don't know why, I just fancied trying a direct drive and in many ways this fits the bill - straightforward with no automatic gizmos to position the arm etc.  According to the Vintage Knob these were made in the late 70's so it's getting on a bit but everything still operates very smoothly so obviously well built.  ( http://www.thevintageknob.org/sony-PS-6750.html )



Sony were obviously serious about their decks in those days - plinth is a double layered affair using aluminium, wood and a resin and fibreglass layer.  The arm uses carbon fibre for its pipe:



Speed is spot on and seems rock solid:



Fitted my Zyx R50 Bloom and now it's playing.





Initial impressions are of a very tidy presentation, good soundstage and plenty of detail.  Bass may be a little light but I may not have got the cartridge spot on and I've only played a couple of sides.  

Edit:  I've just put on Massive Attack's Blue Lines and bass is thunderous

[2ubes]

 Nice find Ian.

 Looks extremely well built
 I particularly like the pitch strobe with the
50/60hz function, and the platter mat with
a serial number. WOW 

 Be safe

 Dan

[ian]

Thanks Dan, apparently that mat is filled with some sort of anti-resonant fluid.  Mark (Divedeepdog) has just bought one of these too so hopefully he will chip in with his impressions.  Once the cartridge warmed up the deck sounded very impressive to these old ears.  Finished off with a bit of Court of the Crimson King - very dynamic and plenty of width.  I couldn't get much farther removed from all the Lenco bodging but it is rather nice to use.  From what I've read Sony were pretty serious about their record decks back in the day but unfortunately those of us who were around were chucking out idlers and ignoring direct drives in order to comply with the belt drive demagogy.

[ian]

Another link  http://classichifi.info/Sony_PS-6750.shtml

[autobayer]

This is too funny or maybe it´s just obvious: next to the Denons we chatted about, this exact model is on my want list for a funky retro 70s deck for a loooong time. Actually since my school days, when I used to write postcards to the distributors to get those flyers. Actually I still have the one with exactly that deck in.
Superb find.
If I were the jealous type, I´d be 

[ian]

Hi Chris,
Yes, thanks for the translation of those German ebay listings for Denons  . It was Keith who told me this was for sale and initially I dismissed it but then I thought OK, good Denons are very expensive, this isn't so bad and it's effectively plug and play once I put a cartridge on it.  Once I'd done a good trawl of the web it seemed apparent that this was a well regarded deck and now I've listened to a few LP's I can see why.  It has real power and drive not unlike a Lenco.  Top could be a little more refined but I think I'll double check the set up tomorrow to see if that can be improved.   Funky 70's?  I suppose your right - I'll have to put up a wall shelf in bright colours
1st year of manufacture 

[ian]

.....and the platter mat with a serial number. WOW 
 Dan

I just checked that Dan, you're right but of course I had it on upside down 

[itskeith]

Ref:

It was Keith who told me this was for sale

Excellent: that must mean there might be a finders fee beer in the offering then   

[ian]

Or maybe a bit of slate

[funkpig]

Good find Ian, how does it compare sonically to your lenco/orbe/DIY/Ittok reference?

[pde2000]

I see the headshell is the same as my sony (hmk70) stereogram's.  The adjustable overhang and azimuth is very handy.  Changing the standard feet of the technics really sharpened it up, transforming a boring performance to very true and exciting one.  A good DD really does sound superb.

[ian]

That's interesting, what sort of feet did you use?  The feet on the Sony are basically plastic but have a gel filling around the fixing bolt.  One of them was a bit loose so I've just given it a little hot glue.  Also took the base board off to see if the caps looked in good order as the previous owner told me they were the originals.  They look OK to me.



Given the description of the plinth, two part, wood lower, polyester and fibreglass upper I'm a bit disappointed with what's actually there.  The wooden bottom part is quite lightweight and the top part turns out to be some damping of some sections of the top-plate.  Upside is there are opportunities to tweak





The grey ventilation cover was also loose, originally stapled in position but now given the hot glue treatment.

Tony, I'm not ignoring your question, I'll reply when I'm confident I've got the set up spot on.

[reinderspeter]

Nice one Ian 

this exact model is on my want list for a funky retro 70s deck for a loooong time. Actually since my school days,

Same here
Apart from this one, that is:

[pde2000]

When Woody reported good results from upgrading the feet i tried m6 nuts and bolts (cheapskate  ) and the improvement was dramatic.  Then i sat the bolt heads on sorbothane domes to prevent feedback, which sounded even better.  Then i ordered a set of 4 feet from thorlabs, that are solid sorbothane with m6 threaded inserts and screws, and that's where i have stopped.  The deck is sitting on a length of slate hearth cut to fit the alcove next to the fireplace, resting on spur brackets.

For quiet listening or recording the bolts were perfect (and almost free).  The technics feet are sprung/damped, with thick felt pads - fine for mobile use.  I think adding mass, or mounting the deck on a massive plinth (the earth) increases the accuracy that's possible.

PS it looks like there is a power transformer bolted to the chassis, and this can be a source of mechanical and electrical hum.  Techy fanboys often make a separate supply as a tweak.

[ian]

 Peter, you'll have to shift a few turntables to afford one of those.  

I've just double checked my cartridge setup.  Tone arm was a bit bum down, overhang a tiny bit short and azimuth a degree off .  OK, I chucked it together quickly yesterday to see if actually worked but now I think I have alignment spot on.  I also gave the phono outs a clean with Deoxit.  That's another nice feature of the deck, no captive leads so you can use phono leads of your choice.

I'm just listening to Rickie Lee Jones' album of the same name.  First side (cartridge cold) again sounded a bit strident on her vocals on the opening tracks but started to smooth out as the LP proceeded.  Rickie's diction on this LP is a bit, well slurly, but it's fairly easy to follow with the Sony set up properly.  "Easy Money" really had my foot tapping and that is a definite feature of this deck, it drives rhythms along with clear and precise bass lines.  The moodiness of "Last Chance Texaco" came over really well.  Second side and "Danny's All-Star Joint" really bopped along too.  On to "Weasel and the White Boys Cool" where the voice is again a little strident when she almost shouts the notes but the band sounds brilliant, great rhythm and the brass comes over crystal clear.  Odd that the brass and lead guitar don't shout whereas the vocals do a bit.  

OK, I've just switched to the digital version of the same album off the Vortexbox.  Crystal clear but it doesn't quite have the same boogie factor.   However, the vocals are also a bit strident!  Maybe I have just forgotten this feature of the album.    In a way quite pleased that it's not the Sony's fault.  To be clear I'm being nitpicking here, it's not that bad with either replay method.

On to Tracy Chapman, it seems eponymous albums only are allowed in this test .  Again the Sony is excellent at driving the music along especially on "Fast Car"  .  It really does grasp the beat and I don't think it would disappoint any Lenco owner in this respect.  Voice still sounds like she was standing a fraction too close to the microphone.  Strangely, when out of the room this is not a problem so I got the wife to pull down the blind on the big window and this did actually improve things a little - maybe because I'm listening critically I'm being over-sensitive.  

On to Court of the Crimson King.  Male vocals just aren't a problem and the clarity on "I Talk to the Wind" is superb, this is really a very quiet deck.

So, to answer Tony's question - preliminary conclusions are that this Sony is a party animal and probably does better at driving along the music than the Idler driven Orbe.  The Orbe is however a touch more refined with female singers, not a lot in it but significant.  The Orbe probably beats the Sony on depth of soundstage but not on width.  Both through out detail and dynamics in abundance but the Sony probably has the edge on the latter.   Peter, Chris, I dare say you can pick one of these up cheaper than here in the UK given they are more abundant, especially in Germany as the spell of the Scottish belt drive wasn't as strong there so go and find one, I don't think you'd be disappointed.