The Edison 60 Kit Amplifier with 300B's

Mon, 12 Oct 2026 00:00:00 +0000

This 300B Parallel Single Ended (PSE) amplifier is based upon the Edison 60 amplifier kit, which is made in the UK. This modified version uses the PCBs from the Edison kit with only minor changes. The biggest changes are in the PSU.

The converted Edison 60 with four 300B output valves.

Thermionic Valve Analogue Stages for Digital Audio

Wed, 07 Oct 2026 00:00:00 +0000

Preface and update

The bulk of this article is retained from the original, written in 1999 and published worldwide first in valve 2/2000.

It is perhaps to the credit of the early revival of DIY Valve Audio as embodied by “Valve” and “Sound Practices” that this article (which owes so much to both magazines and the communities that sprang up around them in the early days of the internet) has remained in demand and is still occasionally referenced.

Reading one’s own writings with a decade distance is often an interesting experience. Yet I feel that overall this article has stood the test of time well and remains relevant in today’s world. In the days I wrote the original article I was working by day on doomsday scenarios where all computers would crash on the first of Jan 2000 and destroy civilisation as we know it or worse and how to stop it from happening (that one went with such a fizzle, I expected more after all that build-up).

The article was written quite aggressively, as it was originally published in an extremely limited circulation, privately published newsletter. I let it stand as was for publication nearly a year later worldwide and decided to do so again a decade later. On occasion a spade must be called a spade, not in misguided political correctness a “wood and metal digging instrument of limited application”.

Valve Amplifiers were a comparably rare sight at hifi shows and DACs or CD players with valves could be compared to rocking horse droppings. Nowadays you cannot swing a cat or throw a brick in any hifi exhibition without it destroying several valve amps and so-called valve or valve CD players in the process. Of course the “valve” CD players and DACs rarely are true valve units; usually they just contain a valve buffer after a thoroughly conventional and often not so well designed solid state analogue stage. Still, one has got to give points for effort).

I have taken the liberty to insert comments to account for a world that has much changed in the intervening decade with 9/11 and 7/7, al Qaeda, the long awaited sequel to Operation Desert Storm, the infamous Taliban prowling the streets of the UK and the RIAA mass-suing its customers, the rise and fall of the Piratebay plus a global economical crisis which would not have looked bad as the Y2K disaster that never arrived.

Some thoughts about singleended Valve Amplifiers

Tue, 06 Oct 2026 00:00:00 +0000

While much practical information exists with regards to the Circuits for such amplifiers, I have noted that very little has been done to systematically research the interactions between Input, Driver and Output stage as well as the power supply. In the end, we want to design and use the best possible circuit for a directly heated triode. This is not a simple or light-hearted undertaking.

From here on it might get a bit mystical, but bear with me….

Articles on Decades of Musings on HiFi

The Edison 60 Kit Amplifier with 300B's

Thermionic Valve Analogue Stages for Digital Audio

Preface and update

Some thoughts about singleended Valve Amplifiers