Parasound JC3 Phono

[ANADIGIT]

Yes, I lived here 4 yesrs ago.
John, patent meant you should keep your product designed away from Ebay seller whom need to sell a copy.

Regard
Anadigit

 

[john curl]

There is NO patent material in the schematic I published. I gave it to YOU to study, and anyone else, as well. In my opinion, it is a good design, but not a Vendetta or Constellation grade design. They are my best efforts.

 

[ANADIGIT]

Great

Thanks, John
I'll try to do a little bit MOD on your product.
I loved its sound but what I though it was Vendetta, I saw many review refer to Vendetta and there're no talk about their different since this week you've shown your designed.

Looking for JC 2 in the next job

Regard
Anadgit

 

[EDDELARUE]

The only real mod for this design is the IC's used.

ADA-4898 ?

ADA-4899 ?

AD-8099 ?

Only speculation

Regards

eD

 

[gk7]

What would a suitable (available) substitute for the 2SK246 Fets be ?

 

[reinhard]

Y means an IDSS from 1,2 to 3,0 mA. Think Fets with IDSS around 2 mA are suitable.
Reinhard

 

[john curl]

Before any details are argued over, let us come to understand the schematic as a block diagram. It is a 2 stage design with the high frequency EQ between the 1'st and 2'nd gain block. (1600 X .047uF) Then the second gain block equalizes the bass boost that is also necessary. This is essentially the same block diagram as the Vendetta Research, except that the Vendetta uses an OPEN LOOP transconductance amp instead of a high feedback op amp. The additional op amp sections add balanced output and servo control of the DC gain. Almost any low current fet can be used as an output offset, or it can be ignored, if you want. The circuit will work without it.

 

[john curl]

Any 1A or so, complementary power mosfets will work.

 

[ANADIGIT]

Stereophile

Everyone, Have you ever seen this review & ranking ?

Thanks
Anadigit

An externally hosted image should be here but it was not working when we last tested it.

 

[toufu]

Anadigit, are you trying to sell a clone version of this or what?

 

[ANADIGIT]

Sorry, there're no reason to do.
You can find many many kits if you want but not for me.
If money is not a matter please you buy a new one as me.

 

[john curl]

Look everyone, I GAVE out the schematic here. Do what you want with it!

 

[RCruz]

Hi John

Thank you for explaining the schematic of the amp.

I am particularly interested in the psu section.... would you care to give us a hint on how you implemened it ?

Regards
Ricardo

 

[john curl]

I don't have a schematic for the power supply. It was taken from the JC-2. However, any regulated power supply of +/- 24V should do a good job, because each channel is BUFFERED in the supply by mosfet cap followers. Try to avoid RFI and make a CLEAN GROUND, and you have what you need.

 

[ANADIGIT]

Supply

Zoom in & a new boy (JC 2)

Thanks
Anadigit

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

 

[RCruz]

I don't have a schematic for the power supply. It was taken from the JC-2. However, any regulated power supply of +/- 24V should do a good job, because each channel is BUFFERED in the supply by mosfet cap followers. Try to avoid RFI and make a CLEAN GROUND, and you have what you need.

Thank you John

 

[RCruz]

Zoom in & a new boy (JC 2)

Thanks
Anadigit

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

You bought another one ?

 

[The Space Egg Corp]

Nice to see a well designed unit, with PSU in the box it's dealing with.

All this seperate transformers...
...seperate boxes...
...seperate pre-regs...
...seperate regs...
...seperate on/off switches ?
( suppose it could be worth it, if LP's came on 2 discs, one for each channel; & you played them simultaneously on 2 turntables )

Next we will need a 'seperate building' to house each channel...
...and a seperate 'power-station' to provide the juice.
NOW were talkin' !

Can't see myself, how it makes having 'solid grounding' easy...
...with all this 'seperate box' malarky.

Seems like the grounds should all go back to the source, ultimatly.
Difficult with a zillion umbilicals & boxes.

Nice job John.

Cheers.

Si.

 

[tiefbassuebertr]

Look everyone, I GAVE out the schematic here. Do what you want with it!

Where?

 

[phase]

1. Search this thread (button)
2. Type “schematic”
3. Read one of the resulting posts which contains the schematic