Photo Gallery

[kodabmx]

The TY-250P will handle 4.5mA of bias so you could use it as a plate load. I did it in a small guitar amp to try and simulate OPT distortion with line levels...

 

[rdf]

Here is an amplifier I just finished.

I have a few of those knobs courtesy of a 1970s CCA FM transmitter but hazarding a guess that wasn't your source. Where did you get those and the Simpson meters?

 

[Galapac]

Thanks! I ordered a few different swatches from a powder coating company in the USA, found the one I wanted and had it shipped to my guy Dave at Landfall Systems. The powder is Distant Blue from Columbia Coatings.

L0rdGwyn, do the LEDs serve a purpose besides the light in the amp? Are you using them for a bit of resistance or other purpose?

 

[gideon1990]

If you google for "tube LED bias" you'll find explanations

 

[Galapac]

Thanks for the lead…I’m still very “green” but learning as much as I can and will probably ask questions that will make some eyes roll from time to time. ☮️

 

[mihail]

6J4 2A3 SE

2A3 SE

 

[goddlediddles]

Schematic.

Beautiful construction. Any chance of seeing the schematic?

 

[JAMESBOS]

very nice, sound good? what speakers do you use?

 

[mihail]

Goodmans

 

[gain wire]

And a side shot. The 807s are Australian JAN ones, they were NOS out of an attic, they even had a stamp "1944 RADAR" on them... Wow

Mhmm I like the nipple clamps on that baby... Bet you she sounds good to when she sings eh?

 

[L0rdGwyn]

I have a few of those knobs courtesy of a 1970s CCA FM transmitter but hazarding a guess that wasn't your source. Where did you get those and the Simpson meters?

The knobs were ordered on eBay, just a random seller, have maybe ten of them but most are a little beat up, this one was the best of the bunch.

L0rdGwyn, do the LEDs serve a purpose besides the light in the amp? Are you using them for a bit of resistance or other purpose?

Sorry just saw this, getting killed by the COVID surge at work, yes the LEDs are used for biasing, it's the "lighting up" effect that is secondary

 

[rdf]

Thanks. Since asking I rescued from disposal a box of 1950's Daven knobs in the cold storage building at one of our transmitter sites. Should be good for long while.

 

[qiuchun63]

The 2A3 SE

 

[WntrMute2]

^ Very classy. But what is the antenna looking gizmo?

 

[zman01]

Here is one more picture with the amp fired up, taken in the dark though so the color is not very accurate. Really isn't accurate in any of the photos, more like the blue on old JBL speaker baffles.

L0rdgwyn,

Nice choice of color, and overall the amp looks beautiful, congratulations!

Some nice product photography also.

 

[alex mm]

New boards for Priboj tube amplifier with OT GU50 PP , work in progress

Regards, Alex mm

 

[soundbrigade]

New boards for Priboj tube amplifier with OT GU50 PP , work in progress

Could you consider sharing the Gerber files?

I modified my Priboi ages ago according to Anatolij Likhnitsky's article in Audio Magazin (RU) in mid 90's. The original 6R3S are powerful but really low-Q tubes and having a 50W 20kg useless/unused "anchor" stored away when it could be playing loud and clear, doesn't feel good.


OR, did you just use the original layout and schematics?

 

[azazello]

SE 4P1L & C3g /next step to change 4P1L to 300B/

 

[soundbrigade]

Hey, Aza-man!
How many 4P1L amps have you built by now?

I am too "busy" with my synthesizers, but I have at least three almost built amps (GU50, 6P1 and 12B4A) that requires a few minutes of attention, some solder and a few wires.

 

[azazello]

Hi, My friend, Magnus! 3 SE 4P1L and a lot of others amps for my friends here.
I have two in "Glow in the dark audio", You can visit it.