FirstWatt J2

[darkless]

Originally Posted by Nelson Bass

A resistor.

Take a look at rev.1 of the J2 at Issue 34 – Magazine | TONEAudio MAGAZINE page 175 (in the High Resolution Version). More simple than rev.0

Looks like Nelson also removed the active bias system for the output JFET in rev.1!?

Interesting. I wonder why he did it. Does anyone know when this revision change took place and whether other revisions were made?

I recently ordered a brand new First Watt J2 from the Hungarian distributor which should be here within the next two weeks. I'd really like to know whether I would be getting the most recent revision if nothing else for the fact that I like having the latest 'n' greatest from the man himself.

[Zen Mod]

there is no audible difference between R0 and R1 , except in heavy clipping state ;

[darkless]

Originally Posted by Zen Mod

there is no audible difference between R0 and R1 , except in heavy clipping state ;

Thank you. Clipping won't be an issue for me. I'll use my pair of Audio Note AN-E speakers with it at first (93 dB/W/m). Later once I have enough money saved up I'll probably spring for a pair of Teresonic Ingenium XR speakers (using Lowther DX4 drivers, 103 dB/W/m). They sound like heaven.

You wouldn't happen to know when the revision change took place?

[rickmcinnis]

My curiosity ...

R0 or R1?

Bye,

[Zen Mod]

let's say that - theorethicaly - R1 will stretch slightly more ;

but - speaking in db range - do not even think about .

in case that Papa made some radical change - from functional view , I think all R0 will be called back to kitchen table

so - that was not a case ....... conclusion is simple - relax and enjoy

[Zen Mod]

Papa is in town ..... now he's going to rub my nose

[Nelson Pass]

According to my schematics, the difference is merely
slightly revised artwork.

[Adams_Leo]

Originally Posted by Tazzz

Here is something akin to a J2 clone ... still work in progress but it plays rather good already.

Do you know which sch be built for this amplifier?Would you please post the sch.thanks

[bdbender]

Originally Posted by Adams_Leo

Do you know which sch be built for this amplifier?Would you please post the sch.thanks

If you are asking for the J2 schematic, please refer to post 20 in this thread. I think we need to respect Nelson's wishes.

[Adams_Leo]

Originally Posted by bdbender

If you are asking for the J2 schematic, please refer to post 20 in this thread. I think we need to respect Nelson's wishes.

Thanks for you remind.