diytube.com

Has anyone built this amp ? http://diyaudioprojects.com/Schematics/ ... ematic.htm
Its looks really easy to follow. Im entertaining the idea of doing a point to point amplifier. any feedback is greatly appreciated

Compare with ST-35/SCA-35 amp schematics.

Here's the 6V6 version:
http://diyaudioprojects.com/Schematics/ ... Amplifier/

There's a lot of mods (including ones here) that improve them

Cheers!

The schematic was taken directly from the 1955 Dynaco catalog.

Page 4:
http://www.the-planet.org/dynaco/Misc/Transformers.pdf

The Dynaco 410 transformer is no longer made. You can substitute for it with the Z-565.

Acrosound made a very similar design for the A-310 transformer.

Page 9:
http://www.clarisonus.com/Archives/Trans/Acro55.pdf

12ax7 phase-splitter, 5Y3 rectifier, 6V6 outputs, etc.

The basic design has a lengthy pedigree. As Geek wrote, you may want to look into the improved version, but I would not use Hammond outputs.

Any output transformer with 8 ohm primary and ul taps will do? Or should I stick with a z-565?

Dk1975 wrote:Any output transformer with 8 ohm primary and ul taps will do? Or should I stick with a z-565?

Any PP UL transformer rated for 15W will do. If you already have such a transformer, use it. The z-565 is readily available and has good sound quality, which is why I mentioned it.

This is the 1940s vintage "floating paraphrase" circuit, just (slightly) updated with newer (1950s-1960s) tubes.

I would SWAG that the Budgie SE could be easily modded to make a monoblock version of the 12AX7/ EL84 design.
Similarly, the Clementine board could support the 6V6 / 6SL7 (12V6 / 12SL7) circuit. (I previously tried it out , but later found I had made a minor
wiring error in the 12AX7 section, so its PP performance fell short of my expectations. The board was then returned to the original 2X SE configuration)

But then, the designs are simple enough, to just wire it up, point to point.

/ed B

I built that early Dynaco with 6V6's about three years ago ...



Bigger pix at http://tmamps.com

I've been on your site a half dozen times and never noticed that one! I doubt mine will turn out that neat. Where you satisfied with the sound?

That's a really simple and good sounding circuit. I might build another one some day.

That one went to Russia.

out of curiosity, why didn't Dynaco go with 6V6 instead of el84 for that class of amp.....?

EL84s were all the rage for low power in the 60s. Octals were out, minis were in.

Octal tubes were on their way out at that time, only used in high power applications.
Octals weren't printed circuit board friendly in that era. Boards were made of waxy
brown phenolic which tended to burn up with heat from hot resistors and tubes,
and they weren't strong enough for big tubes, although some companies tried
and failed.

Remember that Dynaco was making low cost products. No one ever imagined they
would last 50+ years.