[Gopher]

I have a VERY nice Firstwatt F1J clone built by the very generous Tim Rawson.

This amplifier started its life as a Firstwatt F1 with all of the upgrades (Plitrons, cardas jacks, etc.) offered by Mr. Rawson and was happily used for about two years.

Mr. Rawson retired from the amp building game, but I was able to persuade him to do me a personal favor and, after sourcing my own matched quad of Semisouth R100 JFET devices and doing some arm twisting I was able to get him to update my baby for me.

The designer himself, Nelson Pass has this to say on the update:

the F1J delivers a dramatic improvement in current-source amplification. I have often ventured the opinion that improvements in measured performance in simple Class A circuits (particularly with no feedback) usually have the best correlation between what you measure and what you hear, and the F1J bears this out. I think it sounds about twice as good, and I feel certain that you will experience the same remarkable improvements.

I dropped a considerable amount into this unit shipping it back and forth, sourcing parts and paying for labor.








I have this listed on Audiogon for $750 but will let it go to an ACer for $695

[Gopher]

bump

[mr_bill]

As the F1 is a current source amp, what kind of speakers does it match with as I imagine this is not for every type of sensitivity or speaker?

[Gopher]

This amp works best with single or FRD speakers with simple or no cross-over.  I've used it to drive Cain & Cain Abbys and Zu Soul Superflys.  I've also heard its magical with AKG K-1000 headphones.

Don't buy this for your Magnepan speakers, but if you've got reasonably sensitive speakers with a simple cross over network, this may be the best solid state you've heard.

Think of the signature as the Firstwatt F3 with bigger balls.

[shep]

I'm an avid follower of Pass stuff on DIY.com. I have never heard a NP design but I would LOVE to have this amp. Problem; 220 volts (France) and inefficient speakers (86db) Oh well dreams are made of this... someone is going to be very happy with this amp I'm sure. Nelson is one of the greats and those who "clone" his amps (with his support and approval) are a dedicated lot.

[turkey]

I've met Tim and been over to his house. He does excellent work, and he seemed to be very detail-oriented.

I heard one of his NP amps, and also an SKA and a chip amp. All of them were pretty impressive.

So, somebody will be getting a really nice amp when they buy this. 

[Gopher]

Thanks for the comments on the sound quality and builders, guys!

She's a great amplifier--really good solid state.  I'm selling it to pay for an Atma-sphere I just bought, not because I'm dissatisfied with its performance. 

Local buyers are welcome to hear it in action on my Zu Soul Superflys!

[Folsom]

Do you think Rawson has any PCB's he would sell? I want an F1J more than anything else but I lack the PCB's to make one.

[Gopher]

No clue as to what he has still.  I do know he's very much burnt out/disconnected from the hobby now.  My unit started its life about 2 years ago as an F1 and was just updated to the F1J as a personal favor. 

That said, I accepted an offer for my unit and am just awaiting funds!

[SET Man]

Do you think Rawson has any PCB's he would sell? I want an F1J more than anything else but I lack the PCB's to make one.

Hey!

  Than why not just buy this one built by the man himself?

  Building one yourself not going to save you much money than the asking price here, not to mention the time.

Take care,
Buddy