Technics Stock Leads Capacitance Way Too High!!

by **cafe latte** » 19 Oct 2010 04:11

Technics Production Change Report

New Interconnect Cable Has High Electrical Capacitance

AUGUST 6, 2010

There has been a change in the interconnect cable affecting the following models: Sl1200MK2. SL1210MK2, Sl1200MK5, SL1210MK5.
This changeover likely occured in product with 2009 date codes. So that would be serial numbers beginning (GE9A. 9 is 2009, A is January)
The change involves the interconnect cable electrical capacitance. The older cables had a total capacitance of approx 120pF, the new cable is approx 325pF. This change makes the newer models incompatible with most high output cartridges since the total load capacitance for uniform frequency response is typically under 300pF total. Most preamps have 100pF internal, some have more. Adding that to the 325pF of the cable will produce a peak in the high frequency response, with the most likely affect being exaggerated surface noise and sibilance.

Resolution: KAB has notified Panasonic QC and send a letter to Pansonic, Osaka Japan on 8/6/10.
A response from USA has been recevied 10/13/10:
"There was a wiring change in production that did affect the cable capacitance of this model. As you know there are several factors to determine the overall capacitance of the system, but suffice it to say, the old cable had a lower capacitance. Because of the adverse effects, the factory has discontinued the new cable RJL2P001B12 and have reverted back to the old cable RJL4P002S12 in production, since September 2009." So it appears this will be corrected and eventually new production tables will have the original cable.

This is in the News section of the Kab site. There is also some good pics of the Bad and good cables.

by **LPM** » 19 Oct 2010 08:48

Cafe,

I agree you should feel pretty chuffed. Great final outcome.

Just as an update on mine, I got a set of Mk5G cables from Kevin at KAB and sure enough they measured at the 75/6pF stated. Kevin went a step further for the customer as always and supplied a brand new set with the PCB attached so my changeover (last weekend) was simple.

I'm glad I made the change as the treble is sweeter and more extended now despite using my Shure M91 (with SAS) that has an original recommended capacitance range of 400 to 500pF. My old leads had put my total capacitance right in the middle of this range. Now, my estimated total is about 250pF. So, even whilst being well below the Shure recommended range, the sound is a definite improvement though it's not chalk and cheese. Over the next week or so, I'll try my Shure M95 (SAS) that has the same recommended capacitance range but interestingly (unlike the 91 data sheet) says it can go to as little as 100pF with little audible change. Perhaps 250pF will suit it very well. I'll also try my Denon DL160 again though theoretically there should be little effect from the change.

by **cafe latte** » 19 Oct 2010 09:38

Hi LPM glad you got a good outcome. I too found a big difference when I changed the leads. Kab has managed to get replys when no one could (how i do not know) I sent three emails to Panasonic on this issue and all were ignored, but maybe they were noted we will never know.. The main thing is it seems new TT's will be fine (typical there is a problem when I buy something :evil:

) Joking aside all the links that members put on other forums and effort spreading the word must have helped, in my opinion all those who contributed made this happen. Also with a big thanks to Kab
CL.

by **rocker65** » 19 Oct 2010 12:46

cafe latte wrote: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

Hi CL,
Thank you for your reply. 'Tis a good'n.
I had thought about doing some thing similar with the difference being mounting the output sockets on a right angled bracket to enable standard plugs to be used without any angled sockets or adaptors etc.
But then I thought why bother with interchangable leads at all if I am pretty sure of the length of IC required. (Known capacitance per unit length and known cart. requirment).It is added expense which I would like to avoid.
Any thoughts on the benefit of changing the arm leads and headshell leads. There are many marketing claims, but not many user reports.
Thank's again.

by **cafe latte** » 19 Oct 2010 13:09

Hi Rocker 65, i really do not think that arm or headshell leads will make a difference. Your best spend is a better cart if your rca's are not the bad ones. the resistance of the wire in the stock arm is low and better wire has little or nor difference in this respect. capacitance is similar to the 'audiophile stuff' so i really cant see any gain. I have messes about for hours over the years, but a better cart always gives the biggest gain, provided all is set up correctly.
CL

by **fscl** » 19 Oct 2010 14:18

cafe latte wrote:Thanks Ted, but the tip is to all who contrbuted, well done everyone!!

Clatte....... take a bow.....please.....

=D>

WAY IN THE BEGINNING..... page 1....

I believe you started the BALL rolling on this one....

Well done....

:wink:

Fred and wondering if Chinese manufacturing / substitution was responsible for this fopah / faux pas......
:-k

and wondering if Golden Dragon Everright Spec Cable Leads will exist tomorrow..... :-k

and continue to manufacture under Everright Cable Spec Grand Dragon Leads...... :cry:

Branding / Brands anyone... :?:

and impressed by Panasonic / Matsushita admission.... time for some samauri engineers to lop off some heads..... :wink:

by **cafe latte** » 20 Oct 2010 01:13

Thanks guys! But as many things this whole thread started as a bit of an accident.. I was playing with loading on my m97xe ( see the first post). I was hearing little difference. Anyway there is a few things on the net re loading m97xe carts and capacitance is just as important and resistance, so I was curious, and with advice I measured the capacitance of the leads and was shocked at what I found. So really it all started as I was trying to get the m97xe sounding right (which it now does), but I can't say I am not pleased that I started this thread and that it may have helped get this turn around from Panasonic! I have learned a lot also as when I startd all this I had never measure the capacitance of a lead (despite doing quite a lot of electronics) and was not totally sure how. Yes I am super chuffed, but I still feel this investigation was a bit of a VE effort and many gave important input which resulted in us finding out what the problem was. In many other forums it would probably ended in an arguement or something. Anyway only a mini bow from me all the members can fill in and do the rest, also lets not forget Kab for finally sorting this.
CL

by **rivieraranch** » 14 Jan 2011 04:43

cafe latte wrote:Hi LPM glad you got a good outcome. I too found a big difference when I changed the leads. Kab has managed to get replys when no one could (how i do not know) I sent three emails to Panasonic on this issue and all were ignored, but maybe they were noted we will never know.. The main thing is it seems new TT's will be fine (typical there is a problem when I buy something ) Joking aside all the links that members put on other forums and effort spreading the word must have helped, in my opinion all those who contributed made this happen. Also with a big thanks to Kab
CL.

What is the installation like with the PCB attached?

by **cafe latte** » 14 Jan 2011 08:22

easy.. The lead is wire tied to the board, snip the wire tie and leave the board in place(watch the plastic tie does not fall into the arm base , not a problem , but it happened to me and it took tweesers to get it out and it was a bit of a sod). Desolder as I said, when you resolder get mum, dad missus or friend to hold the new wire on the tag on the board (makes it sooo much easier) and simpily solder away. ONE THING THAT IS IMPORTANT!!!! do not rush and keep solder and iron away from the tiny arm leads as they are easily damaged. This should not be a problem as they are not really that near were you are soldering, but if you are talking and not concentrating accidents can happen. It is really quite an easy job, just take your time and if you get stuck or are unsure post and I will answer as soon as I can.
Regards
CL

by **LPM** » 15 Jan 2011 03:25

rivieraranch,

Exactly as Cafe said where you leave the original PCB in place and change the IC lead - so two large solder joins and a plastic tie to be replaced but the latter can be a bit awkward to get right with the thicker/stiffer replacement IC.

Just so there is no confusion, in my earlier post I was referring to the fact that I received the new lead with a complete new PCB board attached (to it) so no fiddling with ties or dressing the replacement lead. However, it meant that I had to unsolder (easy) and re-solder (fiddly) the five (including earth) small arm wires instead. To me that was an easier and quicker option than using the original PCB but others may not. Either way, straightforward if you take Cafe's advice and don't rush.

I wish I'd known about the faulty high capacitance arm wires when I had previously rewired my standard arm (well worth while) as then I would have only needed to do the above soldering procedure once.

by **rivieraranch** » 15 Jan 2011 05:06

Now there is something wrong with the wires in the arm, too?

by **LPM** » 15 Jan 2011 06:52

Now there is something wrong with the wires in the arm, too?

They work fine but some poor deluded souls like me just have to fiddle in the belief that we can always improve things...

by **cafe latte** » 15 Jan 2011 07:52

The arm wires are fine, they are copper plated tin, which is not ideal, but the capacitance is fine. Changing the arm wires will improve things, but we are in diminishing returns area, so I would not worry about it, as it is not that easy to do anyway. I am doing it soon as I bought a spare arm so I am rewiring the spare arm as a project and as I have rewired it I may as well fit it, but I do not expect huge sonic improvements. I will be posting with a step by step with pics when i do.

by **4bullits** » 15 Jan 2011 18:24

I can't see how changing arm wires would make one iota of difference, providing the capacitance ect., of the stock ones are to proper specifications, which should be a very simple thing to accomplish given the distance involved.

Wire can't change sound unless it's acting as a resistor or filter in which case it's no longer a wire is it?

Besides, how can that wire really make an audible difference when the signal has to travel through solder when reaching the PCB board? (Not to mention the clips and socket joint at the other end. )