FS Trafomatic 300B power amp.

[Metlor]

Trafomatic Experience 300b power amp for sale £900.

Excellent condition, really well built, heavy with quality transformers.
Runs almost silently here which is unusual given my electrics.

Had a service approximately two years ago and on recommendation some of the components were upgraded, came back running cooler and performing better.
Very detailed and transparent sounding amp.

The 6sn7 valves are as new, the rectifier and 300b unknown hours to me. The 300b have been marked with pen to indicate position, I can't see any asymmetry in the circuit, but the bias may need checking when fitting new valves ?

I'm in Chesterfield and really prefer not to post this, though would meet up fairly local.

Thanks mart.

[Lawrence001]

Have done some research and concluded this is a bargain. Unfortunately I don't have the right speakers to match to it but GLWS.

[Pigmy Pony]

That does look like a lot of 300b loveliness for the money, GLWS. Forgive my ignorance, but why do speaker outlets have 3 posts each?

[Metlor]

Thanks all, 4 and 8 ohm taps.

[Metlor]

Bump.

[Metlor]

Any interest at £850 ?.

[Metlor]

Bump.

[bumpy]

Lovely little 300b amp for anyone getting started on SET amps, but the comments you put about biasing could put off any potential interest with someone not used to valves.

Its a way to get the main valves to run in their optimum range and balanced to each other. Sometime biasing is automatic and other times it needs little pots to be adjusted pretty infrequently using a meter. Its not a big deal

GLWTS

[Metlor]

Thanks Chris,
I have to say I'm a novice when it comes to biasing valves etc.

It was John Wood in Nottingham who serviced the amp (Just before covid )
He definable swapped out many of the original carbon resistors, and seemed very pleased with how the amp was running.

He was clear that he'd marked the 300b's to indicate their location.
I don't know if this circuit is fixed bias or not, but I assume he has tweaked the bias somewhere to suit the valves ? without putting a meter on it, I couldn't be sure.
With its current valves it is certainly running well and sounding very good.

mart.

[bumpy]

Was just reading the review here.
https://www.6moons.com/audioreviews/...data%20sheets.

It states "The amplifier runs auto bias to not require adjustments when changing tubes." So the guy that serviced it went overboard by marking the location of the 300b's, but there was no need to.

I think I read that the amp has C Core transformers which is very good