Technics Stock Leads Capacitance Way Too High!!

[LPM]

Werner,

I understand that you have previously noted this inaccuracy before but I'm not an EE and as a layman, I can only use the tools and values (such as 490pf for the 160) that I've found on the net. Think of my post as an 'Aunt Sally'. I'm more than happy to be corrected and better advised.

[todd95008]

KAB now has a report on the cable issue up on the web site (under news repor in red):
http://www.kabusa.com/frameset.htm?/m1200.htm

Todd

[analogaudio]

For those who may be wondering about vintage Technics models I have checked a 1700mk2 and an 1800mk2 from the '79-81 period and these have cable marked "low stray capacitance" having the same construction as the 125pF type shown at KAB, with thicker polyethylene insulation for the inner conductor.

Ted

[fscl]

KAB now has a report on the cable issue up on the web site (under news repor in red):
http://www.kabusa.com/frameset.htm?/m1200.htm

Todd

This is proving to be VERY INTERESTING......

What will be even more interesting is to find out / learn of the cable substitution as it most likely was $ub$tituted a$ a co$t $aving mea$ure without any consideration of actual performance and whereby the "Brand" suffers?

Sound familiar?

Fred thinking we're a fringe element anyway..... and wondering what the leads on the AT-PL120 look like.....

[Brisbane56]

For those who may be wondering about vintage Technics models I have checked a 1700mk2 and an 1800mk2 from the '79-81 period and these have cable marked "low stray capacitance" having the same construction as the 125pF type shown at KAB, with thicker polyethylene insulation for the inner conductor.

Ted

Thanks for posting that. I have a 1600MKII still stock that I may mod one of these days.
I had wondered if anyone had checked the older cables.

[fscl]

Updates anyone

Fred

[OneyedK]

If it helps...

My SL1200 is about 10 years old.
Stock leads + arm wiring measure 102pF.

I replaced the RCA plugs and now I measured 12pF,
so the capacitance was where it should've been, if it was meant to
keep RF out of the preamp.
I'm running a Denon DL-110 so capacitance didn't matter anyway...
(380µH inductance)

C-meter is Meterman CR50 and yes, it was calibrated.

[majerjack]

2009 SL-1210 M5G, output cables labelled "Technics High-Fidelity Audio Cord", capacitance meter tested on 1% tolerance polypropylene capacitors, capacitance from tone arm cartridge connectors to RCA plugs less than 70pf each.

[cafe latte]

Seems there is a few leads being used. Mighty wire seems to be fine and from your findings Technics high fidelity cords seems fine, the problem seems to be the TT's with just a code on them as stated on this thread earlier. An update.. I have made up a plate for the arm base of my TT using the original as a template, and fitted a couple of phono sockets to it, plus right angled phono plug adapters so the leads fit under the TT. This way I can use any leads.

[OneyedK]

sorry folks, just measured again, it's 92pF not 12pF.
12 pF would be impossible

[rocker65]

Hi All,
Just as an aside, besides having to ensure that the IC capacitance is correct for the Cartridge being used, is there any benefit in using a "high", or higher quality than the standard Technics lead. If this is the case exactly how does one quantify the "Quality" of a lead?
I ask because there are so many available in the marketplace and the capacitance is just one parameter.

[analogaudio]

Yes it is a puzzle isn't it, so many offerings and little supporting technical data to be seen, few measurements, few specs, but a hefty price tag and poetic descriptions.

Aside from the critical application of phono interconnect I find generic interconnects satisfactory, especially considering the imperfections imposed by speakers and listening room acoustics.

Ted

[cafe latte]

In a word... No. Interconnects and speaker cable are big business. If interconnects are well shielded and of reasonable quality I really doubt anyone can really here the difference. Capatitance however for MM carts is very important as this thread explains. As an update to this thread Panasonic recently said that they has withdrawn the bad cables and gone back to the old low capacitance type! Bit of a victory I think!!
Back to your point unless you have a newish Technics with bad leads others have reported there is really no benifit in changing the leads apart they may look nicer.. Dont get me started on directional cables when the signal is AC.. Grumble grumble
If you do really want to change the leads remove the platter lock down the arm remove 45 adapter. Turn over TT (I do it with lid on on the sofa). Remove all the screws underneath. Remove rubber bottom, then undo the screws on the circular metal plate under the arm.
with care not to touch the thin arm wires desolder the rca's and snip the wire tie.
The plate you have removed use as a template.. I used a piece of steel, but I am sure aluminium would be fine. Draw round the old plate with a marker and dot the screw holes.
Next with a dremel and care cut out your new plate.. it will take about half and hour.
Next drill the dots for the screw holes.
now in the center of the platedrill holes for rca's (I used the type already mountd on a small bit of plastic and I I did it again I would make a little spacer to raise the rca's a bit so they poke through the rubber base a bit).
I snipped the solder terminals on the rca sockets a bit to ensure they did not touch the board inside.
I soldered good quality hook up wire to the the rca sockets, leaving a bit of length so when the arm is raised it does not pull the wires.
Now solder to the board in the arm and reinstall the plate (I stuck a bit of insulation tape over the connections just to be safe, but it is probably not needed).
Now there is not room for rca plugs under the table so I used gold plated right angle rca adapters, this is why a spacer helps as it gives a bit more room.
Hope this helps
CL

[analogaudio]

Panasonic recently said that they has withdrawn the bad cables and gone back to the old low capacitance type! Bit of a victory I think!!
CL

Yes certainly a victory, a tip of the hat to your good sleuth work.

Ted