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Old 31st January 2009, 04:36 AM   #31
HKC is offline HKC  Hong Kong
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Hi Mr. John Curl

VR5 forms part of the feedback network of the line stage, since I am not using balance control for my JC-2 clone, may I ask you what the value of the resistor should be for VR5?
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Old 31st January 2009, 05:16 AM   #32
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HKC, did you find the upgrade article from Positive Feedback that John Curl mentions?

If so can you please send me a copy.

thanks, sp
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Old 31st January 2009, 11:37 AM   #33
HKC is offline HKC  Hong Kong
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Quote:
Originally posted by stoolpigeon
HKC, did you find the upgrade article from Positive Feedback that John Curl mentions?

If so can you please send me a copy.

thanks, sp
Hi sp

Please advice your mail box.
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Old 1st February 2009, 12:22 AM   #34
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HKC, please send to:

sandiefxz@_____.com where _____ is gmail

thanks again, sp
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Old 3rd February 2009, 10:09 AM   #35
gk7 is offline gk7
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Default upgrade article from Positive Feedback

Hi HKC,

i just received a mail from Positive Feedback: "Sorry, we no longer sell or have back issues." Would you mind to send me a copy too ?
(Email: gk7@billrothhaus.at).
I own a ML-1 and one of the line modules recently started to make some crackling noise the first minutes during warmup, so it might eventually fail some time in the future. I plan to make replacement line modules (as close to the original as it is possible with modern parts, at least performance wise). The should fit in the original JC-2/ML-1 chassis of course, but would make a nice "building block" for other DIY line level applications as well, I believe.
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Old 3rd February 2009, 06:02 PM   #36
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I wish you well in making replacement modules for the JC-2, ML-1 preamps. I am just too old and tired to do it myself, but the need is there, and it is always a shame to see such a nice chassis discarded, because of lack of modules. I got a free JC-2 that way, but it was only valuable because I could fix it with pre-existing modules. Today, I am out.
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Old 3rd February 2009, 06:41 PM   #37
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Anyone with a dead JC-2 can contact me. No, I won't repair it, per se, but I've always thought it was one of the most attractive preamps made and I'd love to build something into the chassis.
The basic circuit topology is still viable, but obtaining original parts is difficult and there are changes that could be made to update the thing to more-or-less modern standards. If I recall correctly the phono stage EQ is flawed--something I believe John would admit--although it can be tweaked to greater accuracy.
Hell, even if I don't build anything into it, I'd just like to have one around to look at.

Grey
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Old 4th February 2009, 11:09 AM   #38
HKC is offline HKC  Hong Kong
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It is very hard to found a JC-2 these days. One was selling @ USD3500.00 from Hi Fi Do Japan about 2 months ago.
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Old 4th February 2009, 02:03 PM   #39
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Quote:
Originally posted by HKC
It is very hard to found a JC-2 these days. One was selling @ USD3500.00 from Hi Fi Do Japan about 2 months ago.
There are currently two ML-1 for sale on that well known internet auction house, but no idea what the final price will be. (I bought mine in good condition and fully working for approx. 1000 EUR one year ago.)
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Old 4th February 2009, 02:35 PM   #40
HKC is offline HKC  Hong Kong
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Quote:
Originally posted by gk7


There are currently two ML-1 for sale on that well known internet auction house, but no idea what the final price will be. (I bought mine in good condition and fully working for approx. 1000 EUR one year ago.)
1000EUR is a good price. It was few months ago, a ML-1 from Australia auction house end up with USD3000 something.
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