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Long cables from turntable or phono stage

Hi I have a question that involves a compromise. I have a turntable that (for various reasons) has to be positioned a little distance from the hifi, about 4m of cable. Would it be better to connect the turntable (transcriptors hydraulic reference, ADC XLM ii) to the phono stage (moon 110LP) then run long singled ended cable to the amplifier or should I run long extension cable from the turntable to the phono stage and use a short interconnect from the phono stage to the amplifier? For visual reasons the latter is better. Any thoughts?
(Amp is plinius tautoro/SA103, speakers confidence C1 Dynaudio, tautoro is the line stage only version).
ninox
dbphd
1,633 posts
 
Al,

The input capacitance of the JC-3 is about 200 pF. I'll probably use Mogami 2549 cable cut to length for my application, most likely around 3'. I suspect LA Pro Audio can tell me the capacitance per foot. They've been very responsive to making cable lengths to my specification. The advice I'm getting is to keep the cable short without putting the motor of the TD 124 on top of the JC-3.

Thanks for your help.
db
nick_sr
263 posts
 
Db,

Here is the link to the Mogami spec sheet:

http://www.mogamicable.com/category/bulk/microphone/quality_balanced/

I bought my cable online at Redco Audio in CT
almarg's avatar
almarg
9,670 posts
 
09-22-13: Dbphd
The input capacitance of the JC-3 is about 200 pF.
Interesting. I'm surprised it's that high. The optimal load capacitance for many and probably most MM's falls somewhere in the area of 100 to 300 pf. A phono stage input capacitance of 200 pf would make it impossible to optimally match nearly all of those cartridges, the possible exceptions being those in the 250 to 300 pf area when used with short lengths of low capacitance cables.

How did you obtain that information?

Best regards,
-- Al
almarg's avatar
almarg
9,670 posts
 
DB, after checking further I found the following quotes from John Curl, the very distinguished designer who as you are undoubtedly aware did the electrical design of the JC-3. The quotes appear on pages 3953 and 3956 of this thread:
There is a 100pf cap at the input to ground for the JC-3. Some criticism has made me now wonder if 50 pf might be better?

... My best guess at this time [May 20, 2013] is that the effective input capacitance of the JC-3 is 125pf or slightly less. I could drop that in half, and I might, in future. The potential advantage may not be worth much. I will think about it.
Best regards,
-- Al
dbphd
1,633 posts
 
Thanks for the link, Nick. I'm going to try a pair of the 2549 Mogami cables.

Al, it appears as though there may be a capacitance mismatch, so I may need to add capacitance using the device you suggested after I install the Mogami cables. I'll do some careful listening first. The sound is superb with the AQ cables I'm currently using, with no HF roll-off or thinning. There is a low level sizzle that I can hear if I put ear close to the HF driver, but not audible to me at my listening position. I hope shorter cables carefully routed will end that sizzle. I think the 2549s are designed to resist such interference.

db
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