Need to build JC 2 preamp

Here is a picture with the modules at work. I will do some measurements
in the next days and post them here if there is interest.



Dear GK7,
I wonder if these PCB's are actually still available somewhere or is there a filmsheet that I can use to have the PCB's made?
I also would like to have this for the phono modules of the JC-2/ML-1
I have one with a noisy attitude that needs fixing.
Greetings,
Mario Gert
 
Hi
just buy the jc-2 kit from eBay:
the recommends are:
• Input stage : 2.5-3MA
• Voltage amplifier stage : 20-25 MA

i suppose that VR2 change the currents input stage? and 3mA*R17=0.18v ??
how i change the amplifier stage currents ?

the gain according to eBay is 3.7, can i change it? how?
thanks
Dear Erez2012,
Where are these PCB-s for sale?
Greetings
Mario Gert
 
I have tried both, many, many years ago. Not sure what is best. But my clone has been in storage for years and years. Now using a better design, with JFETs not available to John in the early seventies.

Would that be N-channel Jfets like J113 from Intersil ? (Dennesen used these in the Sirius preamp).
Or the dual sk170 aka 2sk240 often used for MC stages?

please share
 
Would that be N-channel Jfets like J113 from Intersil ? (Dennesen used these in the Sirius preamp).
Or the dual sk170 aka 2sk240 often used for MC stages?

please share

First time a purchased E110 as shown in the Audio Amateur schematics. That is, for the RIAA input. The bipolars were 2N4401/4403 and the output was E212 and E175. Next time I used J110, J212 and J175. I do not remember, but I am pretty sure those are identical except for the package.
(Beware that the line stage in the picture contains an error which was corrected. I cannot find that picture.)
BTW there are some complete JC2 clones on eBay - complete with transistors - I do not know what transistors are used, but they sound OK enough.

/RK :cheers:
 

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Levinson Line Amp modules

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.

Your @mail adress does not work anymore...
If interested in modules, send me your mail adress
mgrouwenhorst..................X.............H..mail......