300B PSE music at last

[paul(555)]

Finally finished and working, one minor fault on the star earth, my fault, and a problem with the battery bias to V1 which I decided to include from scratch.

The end result is excellent and a further substantial move forward from my history of using valve amps since the late seventies. (Leak Stereo 20 followed by Quad IIs)

Build includes the bits included in the box of bits I bought from e-bay, Jensons at C2 and C4, Black Gates at C5 and C6, largely Holco resistors but with Vishay thick films for the higher values, BHC Areovox for C11 to C14. Plus added EH Gold Grid 300Bs, JAN GE small valves and RCA rectifiers.


Thanks for all the help and advice provided by the forum, especially in sourcing missing parts, much appreciated.

Now, has anyone got suggestions for further useful mods for when the urge to modify overwhelms me?

Paul.

[Greg.]

Well done Paul, but you forgot the most important bit.

How does it sound?

Best wishes,

Greg

[paul(555)]

Hi Greg,

Well until yesterday evening, when one of the amps malfunctioned, they sounded excellent. Very clear and open, with all the lovely mid range clarity of my old Quads but much more so. Also much improved bass performance and power, infact better all round and a significant step forward straight from switch on.

I now need to find the fault and get some hours on them. Definately a learning process!

paul.

[Richard]

Hi Paul

Are you using the 300bpses into Pro9s? If so they should be lovely once you've debugged them! We've possibly traveled a similar route. I've had 3 pairs of Quad IIs, each time thinking I couldn't live without after selling a set - buying again, then realising why I'd sold them - they are lovely but just not quite enough power and scale for my types of listening. I'm presently using 300bpp and it works very well with these speakers.

Rich

[paul(555)]

Richard,

Yes the 300Bs are driving my venerable and much loved PRO9TLs. I've occasionally thought of replacing them, but each time I change something in the rest of the system they allow the improvement through and have yet to get in the way, so why change. Thanks for the PM with tweaking tips for them, I'll be sure to follow that up once I've sorted out my current problem with one of the amps, probably my fault as I allowed my meter probe to touch both the DC pin and AC pin on valve 2, followed by a hum from the speaker and not much else!

The Quads will no doubt end up on e-bay when I've cleaned the dust off.

Paul.