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Ammonite Audio
31-10-2009, 17:07
I've finally got around to cleaning out the main bearing of my old Kenwood KD-770D, as it was a bit sticky and there was a 'sense' of speed instability, even though the rotational speed was measurably correct. The bearing is quite a stout, flat ended affair, with a plain greased sleeve. The end of the bearing sits on a small teflon thrust pad. I've lubricated it using some synthetic gear oil, which makes it run a bit more freely.

The main point of this post is to show how well designed and engineered the Kenwood motor unit is. Unlike the Technics SL-1200, whose bearing is not particularly firmly attached, the Kenwood's is bolted very firmly to a large corian type block, which in turn is bolted to the turntable chassis, spreading the load very widely. The big nut underneath the motor unit that you can see in the first picture below secures the bearing assembly very firmly to that block.

http://i155.photobucket.com/albums/s301/hugocass/Kenwood%20KD-770D/IMG00026-20091031-1640.jpg

http://i155.photobucket.com/albums/s301/hugocass/Kenwood%20KD-770D/IMG00025-20091031-1640.jpg

http://i155.photobucket.com/albums/s301/hugocass/Kenwood%20KD-770D/IMG00028-20091031-1641.jpg

This weekend should see the old Kenwood reassembled, and ready to go head-to-head with the Technics (again). I just need to knock up an armboard to fit the Jelco 750D arm to the Kenwood.

Tolstoi
31-10-2009, 19:11
Nice pics!

Cheers

Joerg

DSJR
31-10-2009, 20:21
Have you still got the Kenwood arm? Mines a bitser in need of much TLC and I'd like to get one with the counterweight decoupling in one piece (it uses a length of piano wire rather than a bolt and nut to hold the counterweight stub in place...)

Ammonite Audio
31-10-2009, 23:27
Have you still got the Kenwood arm? Mines a bitser in need of much TLC and I'd like to get one with the counterweight decoupling in one piece (it uses a length of piano wire rather than a bolt and nut to hold the counterweight stub in place...)

Sorry - I sold it on a couple of years ago. The lift/lower solenoid circuit was defective, so the arm was of no use to me.

Ammonite Audio
31-10-2009, 23:28
Nice pics!

Cheers

Joerg

Believe it or not, those are photos from a Blackberry 8900 smartphone!

NRG
01-11-2009, 11:36
Nice Deck the 770, crying shame the one I bought on Ebay never managed to make it across the Atlantic.....'lost in transit' or 'never shipped'....I don't know...either way a few 100 quid down the drain... :steam:

Ammonite Audio
01-11-2009, 12:18
OK - the Kenwood is now set up with my TecnoarmA and Ortofon Kontrapunkt B cartridge. Immediately, the oiled (rather than greased) bearing has brought about a sense of stability, ease and natural musical flow. It was the 'sense of stability' bit that troubled me before.

This is now a no-brainer for me. I just have to work out how to keep the oil in the bearing. In the meantime, an occasional drop of oil to keep things properly lubricated should prevent any damage.

Here is a picture of the KD-770D, now playing:
http://i155.photobucket.com/albums/s301/hugocass/Kenwood%20KD-770D/IMG00029-20091101-1201.jpg

It's now sitting on Stillpoints OEM feet:
http://i155.photobucket.com/albums/s301/hugocass/Kenwood%20KD-770D/IMG00030-20091101-1201.jpg

DSJR
01-11-2009, 12:21
Looks good - my arm is from a KD750 with integral arm rest and cueing device - DUH!!!


How's that Kontrapunkt? I found them dull and "squidgey" myself, but time may have changed them?

Ammonite Audio
01-11-2009, 12:41
The Kontrapunkt is a bit long in the tooth, and could probably do with a service check and even a retip (as Neal has done with his), but it's certainly not dull or squidgy. I find it to be rather vibrant, sparkling even, and properly set up it's pretty good across the frequency range - at least in the Tecnoarm (which was recently rewired by Audio Origami with good-old-fashioned copper cable). One of the reasons I like it is that it has straight sides, so alignment is pretty foolproof. I'm not in the market for 750 cartridges any more, and would love to be able to compare it to an AT-OC9 or AT33PTG.

DSJR
01-11-2009, 12:50
Apologies, I do know that one of them was as I described and thought it was yours judging by the colour of the trimmings......... :)

The PTG will have a livelier quality to it still, I suspect and, until I find what's changed in my preamp (line stage is fine still), I've gone back to a Supex 900e (black bodied one), which sounds better in terms of timbre than the "flatter response" Stilton OC9 and "cap 210" loaded Ortofon M20FL Super.