Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Kaptinkangaru on August 27, 2026, 09:53:50 pm

Title: 6021W High Gain Submini Amp
Post by: Kaptinkangaru on August 27, 2026, 09:53:50 pm: Greetings all, first post. Wanted to share my latest creation, a 1 watt amp using 3 6021W's. Topology is 3 gain stages into a cathode-driven tone stack, driver stage, and SE output. 12V in is converted to 6.3V using an LM317, and high voltage is provided by a Royer oscillator. B+ ~290V. Designed in EasyEDA, board milled on desktop CNC, 3D printed enclosure for power supply with fan for the LM317, jammed into a Hammond 5x4x2 enclosure. More pics and videos to follow, i seem to have hit the limit. Let me know what you think!
Title: Re: 6021W High Gain Submini Amp
Post by: Kaptinkangaru on August 27, 2026, 10:09:20 pm: shot of the power supply, and one more glamour shot.

vids linked below, no clue if or how i might attach one:

https://photos.app.goo.gl/ru9Tx2R17fQfAPdY8 (https://photos.app.goo.gl/ru9Tx2R17fQfAPdY8)
https://photos.app.goo.gl/6Y5zaPdXrrMERH6w7 (https://photos.app.goo.gl/6Y5zaPdXrrMERH6w7)
Title: Re: 6021W High Gain Submini Amp
Post by: fossilshark on August 28, 2026, 01:36:45 am: Wow thats a work of art! How did you do the silkscreening on the board? I am very close to pulling the trigger on a desktop mill but getting silkscreen results like that seems to be tricky.
Title: Re: 6021W High Gain Submini Amp
Post by: Kaptinkangaru on August 28, 2026, 07:25:43 am: My wife has a ton of craft stuff, including a printer with sublimation ink. I print my silkscreen on it, and use a heat press to transfer the ink. If you've ever done a toner transfer for a PCB etch, this is about 50 times easier and more reliable/consistent.
Title: Re: 6021W High Gain Submini Amp
Post by: dogburn on August 28, 2026, 09:09:47 am: Looks great and sounds great. You get some Nirvana-sounding tones out of it.
Title: Re: 6021W High Gain Submini Amp
Post by: kagliostro on August 28, 2026, 09:22:37 am: Nice Job :thumbsup:

Franco
Title: Re: 6021W High Gain Submini Amp
Post by: sluckey on August 28, 2026, 09:25:27 am: Multiple skills. I like that! :thumbsup:
Title: Re: 6021W High Gain Submini Amp
Post by: Kaptinkangaru on August 28, 2026, 10:43:26 am: Quote from: dogburn on August 28, 2026, 09:09:47 am
Looks great and sounds great. You get some Nirvana-sounding tones out of it.

Thank you. I wasnt going for any specific sound, rather I was experimenting with how much gain I could eek out while still keeping things relatively tight. In my mind, its somewhere between an early Mesa and a hot rodded marshall. The tone controls appear simple, but offer a very broad range of sounds.

Quote from: sluckey on August 28, 2026, 09:25:27 am
Multiple skills. I like that! :thumbsup:

Part of why I love this hobby, next skill to master is woodworking. I've got a few headshells to build. Have some nice exotic boards, saws, routers, jigs, etc.....everything but the expertise lol. Hoping the time permits this fall.
Title: Re: 6021W High Gain Submini Amp
Post by: sluckey on August 28, 2026, 10:51:27 am: With your eye for detail I suspect you will do well with the woodworking. Always count your fingers! :icon_biggrin: