[sanlanman]

I am putting my seldom used Pio Series 20 PLC590 table and PA1000 carbon fiber arm back into regular use. I has sat little used in recent years partly because it has a vintage 1991 AT OC9 moving coil cartidge and my current (temporary) Yamaha receiver only has a moving magnet phono stage. ( I am moving up to a separate amp/peamp combo in the near future.)  Here are some pics:









I still have a DECCA carbon fiber record brush, ultrasonic stylus cleaner and Audio Technica Stylus Cleaning fluid and I just bought the AI record cleaning fluids. Also, I still have the dust cover in good shape, but I removed it and the headshell before the photos. I have ordered a Besttractor alignment tool from Yip in Hong Kong and have a digital scale suitable for use in setting the tracking force.

Questions:
1) I need to replace the cartridge. I am debating over going with a new AT OC9ML moving coil cartridge and get a separate phono preamp such as a Cambridge 640P or go with an AT 150 MLX moving magnet cart and maybe still get the Cambridge Audio 640P a little later on. Or do you have other suggestions.

2) Is the Cambridge 640P the most appropriate preamp if my budget is under $500.00 ?

3) My tone arm uses a cable with a standard DIN fitting but the cable appears a cheap and a bit basic. I am considering replacing it with the FURUTECH AG-12, but am open to other suggestions.

4) I would like to build an isolation platform, but I am torn between a maple butcher block platform and a sandbox platform. The PLC-590 had flexible spider shaped rubber cushions between the chassis and the circular feet, but I think the foot mounting bolt still transmit some vibrations.

5) The platter is about 4 pounds of machined aluminum and very resonant, but there is hardly any room for something like plasti-clay due to the tight clearances between motor and plinth. The rubber platter mat does a fair amount of damping on its own. Any alternative damping ideas, or am I just over obsessing here?

6) Any other tweaks or suggestions come to mind that would improve performance at moderate cost?

All suggestions are appreciated. I have already lurked and learned a lot here, but I'm hoping to dip into that well yet again.

[TheChairGuy]

You're definitely not over-obsessing on #5 - the ringing platter.

Direct Drive units' particular achilles heel is the fact that the platter is a direct extension of the motor...so the motor transmits everything to your platter, to your record, on into your stylus and into your sonic chain.  A buffer, or damping system is needed to damp your energy transmitting platter, while still interfacing well with your record (vinyl).

The standard recommendation is an Isoplatmat ($100) sub-mat (to damp your platter well) and a Herbie's top mat (to interface with the record with some vibration damping characteristics, and a good impedance match for vinyl itself).  The Herbies is about $60 nowadays.

If you're handy and can trim a 12" round sub-platter yourself, you can buy some EAR Isodamp (0.675 or .125" depending on how long your spindle is) and fashion a submat out yourself.  A 12" x 12" is $30.00 from Michael Percy Audio and works fantastically well as a buffer/damping agent (this is what I use).  Then, buy the Herbie's mat and you'l b doing much good for yourself.

Nice looking table, btw, never heard of the company myself 

John

btw, if you have air/dead space inside your deck - fill it with Plast-i-Clay or similar modelling clay.  Most DD decks take between 5-9lbs.  At $4 a pound of clay or so, it makes a fantastic upgrade for most folks.  Try it before buying/making an isolation platform - the two together may seriously take you to a better analog place.

[sanlanman]

Thanks for the advice John. I am somewhat of a DIY guy so I will look into the EAR Isodamp, and Herbies mat. On the plasticlay, will it adequately stick to a surface above it? The plinth is cast aluminum too and would probably benefit from plasticlay, but there is not much for the clay to grip to.

The headshell that is on it is an old Audio Technica headshell and the old Audio Technica Safety Raiser (arm raiser) is still there and working too. The turntable is completely manual and quartz lock controled. Or, the quartz lock can be switched of and then the VU meter illuminates, allowing speeds to be varied using the small knobs in the middle of the control panel. The tone arm shaft is carbon fiber. This combo has been a rock steady performer over the years but, until now, I have not tried to get the most out of it, mainly out of frustration with ineffective record cleaning methods in years past.

Series 20 was a separate line of high end audio gear started by Pioneer back in the late 70s. It fizzled out sometime in the mid eighties I think, but this turn table got some great reviews at the time. For me, its definitely a keeper.

[TheChairGuy]

Yeah, just jam the PlastiClay anywhere you can on any surface inside...so long as it does not interfere with moving parts or create heat issues around delicate electronic components.  Jam them in the corners first, then after you look awhile, you'll find other places to put the clay. 

It's a phenomenally good tweek for any Japanese TT with a plastic body.  It's sticky when you pack it down - no movement once placed hard in there.

The EAR Isodamp is a bit thick to cut with scissors at the 0.125" thickness (you'll need shears), but the 0.675" thickness is a cinch.

Mostly, the thickness you choose will be in line with your vertical tracking angle of your tonearm and cartridge.  If you can put the 0.125" thick section on, with a top mat on top of that, have the right VTA (and some spindle room left to put your record on)...then that's the right move for you.  The thicker the better - the more you can damp that delicate cross-section on a DD machine, the better I'd think.  Just make sure you use something else, that matches better with the records, on top of it.

By all means, experiment if you'd like...I just found this to be a very effective combo for playback.

Look hard at your platter for place to put clay....some don't have it to do it.  Note that clay is fairly heavy and may upset the delicate balance of the platter.  If it was Pioneer's higher end line, they may have put extra care into balancing that platter.

If no room or you don't want to mess with clay on the bottom of your platter...you may want to tray spray damping compound. My fave is Dupli-color UC103...it's cheap and fast drying (less than an hour)...many of these need over 24 hours+ before drying.

http://www.duplicolor.com/products/undercoating.html

Regards, John

[sanlanman]

More good info. Thanks

[sanlanman]

I have done some further checking and the clearance between platter and base is tight. No putting anything under this particular platter. I am going to order a Herbie's mat next week. I have ordered a FURUtECH AG12 phono cable for the table, (got a pretty good price). I still have not pulled the trigger on a new cart or phono pre. I am still leaning toward the AT 150 series cart though. I would like to keep the cost of the cart and phono preamp to around $300.00 to $400.00 each, or am I cheating myself out of significant preformance gains by holding my budget that low?

Further options and suggestions are appreciated.

[TheChairGuy]

The clearance between platter and deck on nearly all these direct drive units are tight...they were generally made with a level of preciseness (balanced, et al) that eludes most turntable makers today.  Spray damping compound, the Dupli-Color or other brands (they do all the same really....their rubberized properties trap and release energy) will fit there....it's barely 1 mm thin once sprayed.

The Technics SL-1200 has long had a 1/8 (probably 3-4mm) or so of rubber on the underside of the (thin aluminum) platter...it works very well.  Tho you don't have that kinda' clearance on your deck (my JVC DD's had very little clearance either, but I Was able to lay down 1 mm or so under there).

The effect of adding it in this thin a coating in minor.  Far more benefit will come of a good, heavy damping mat on top of your platter...and under your top mat (Herbie's works very well).  Herbie's is a fine interface with your records, but I found it minimally effective at damping your (ringing) platter.  The two together work wonderfully.

Don't forget the Plast-i-Clay....it's quite an enlightenment in better sound for very reasonable outlay in $$ (and give yourself a couple hours time to patiently do it).

Feedback rejection and damping are likely far better expenditures of your finite resources than upgrading to a more costly cartridge.  I hear nothing but raves for the wee Cambridge unit at attractive prices.....do all you can to damp and drain energy from your deck (I like brass toes pointed down into a thick wedge of maple butcher block myself....3 different DD units now and all have benefited substantially from this method over squishy (sorbothane-like) puds, Vibra-Killers (I've not found these successful anywhere yet...truly dollars wasted on this one), wood chocks or stock feet.

That really is a pretty handsome deck - hope all these pointers get it to sound good for you.

John