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This circuit sounds really good. Magnetic components has the transformers specific to this amp, but you would probably want to build it with a multitap SE OT as the stock Supro OT has a 3.2 ohm secondary.
Factory Schematic: Turret board layout: My version with all my mods: Cab plans:

As she sits now, in temporary 5E3 cab: What I gave up after falling in love with my 1616t:

Very cool! I have the same amp, but with different cosmetics:




In comparing the two layouts, it appears that your mods added an Intensity pot, a cathode bypass cap for the second stage, and a cathode bypass cap for the power tube. Did I miss anything?

EDIT: added the gutshot

You got it! Not alot you have to do to make this amp play nice with bigger speakers, with an 8" the bottom end is not an issue but with 10's and 12's it got pretty flubby. The intensity control makes the tremolo a little more versatile, and is borrowed directly from a S6424. 2nd stage cathode bypass is there for a little more stripping of the lows and some additional grind. Cathode bypass on the 6V6 can be from 500uF-2000uF Zaphod_Phils "big cap trick" to stiffen the amp up a bit.
I really like the place where the amp sits, still greasy like a Supro, but with a bit of Marshall grind. Mine came from ebay as just a chassis with terminal strips hacked, missing, and mangled and the caps in the cap can were kaput. I rebuilt to stock schematicwith a turretboard and then started making mods with the guidance of Rock_Mumbles and Zaphod_Phil at Wattkins/Sewatt/18watt.com.

Sorry for diggin up...
Any sounds?:)

Cool....I just remembered that I have a spare second hand 6V6 tube somewhere, might try building one of these one day....

I have some youtube videos. The audio quality is so-so, I used my panasonic Lumix stills camera to take the videos. All these clips were made to demo the tone of selling wah pedals I have sold on ebay, but it gives a good idea of the tone of the amp as there are brief pedal-less parts and also parts with delay, phase, distortion, and mucho wah.

Here is the amp currently with new weber Blue Pup ceramic:


here with the previous speaker a blue pup alnico :


and in comparison to a Fender DRRI:

timbo_93631 wrote:I have some youtube videos. The audio quality is so-so, I used my panasonic Lumix stills camera to take the videos. All these clips were made to demo the tone of selling wah pedals I have sold on ebay, but it gives a good idea of the tone of the amp as there are brief pedal-less parts and also parts with delay, phase, distortion, and mucho wah.

Here is the amp currently with new weber Blue Pup ceramic:


here with the previous speaker a blue pup alnico :


and in comparison to a Fender DRRI:

The amp sounds really nice, I particularly like the clean tones that you can get with it.....

thanks mate, i found the videos on utube before
i'm still lookin for some clean sound of this, because a friend of mine needs a new amp and he plays clean most of the time

plexilover wrote:thanks mate, i found the videos on utube before
i'm still lookin for some clean sound of this, because a friend of mine needs a new amp and he plays clean most of the time

Check out this website, there's a few cool amp projects there:


http://www.ax84.com/

Yeah, if you are looking for cleans this guy is probably not the best way to go. It is cathode biased and doesn't have negative feedback, distorts before it is turned halfway up. I can roll off the guitar volume for cleans, but I really like it to sit just on the edge of breakup where it sounds really warm. If I really dig in it distorts, playing softly there isn't so much breakup. I always mic it live. If I were to try and compete with big amps onstage it would be difficult to cut through the mix. It is only 4-5 watts at best. If you want real cleans at stage volume it would be best to do something with a pair of 6L6's in push pull and NFB, Fender Twin etc... If you built this Supro with a 6L6 or an EL-34 and a 15 watt SE output transformer you should be able to get a little more headroom and still keep it simple.

I see that I'm reviving a pretty old thread here. I recently tracked one of these little gems down after being introduced to them at a vintage guitar store in Cincinnati. Mine has an issue of shutting off abruptly after anywhere from 2s-30min of playing (usually on the shorter side). The amp light stays on even when the sound cuts out. If I turn the volume knob off and then back on a few times, the sound will come through again. Then the process repeats. All I've tried so far is replacing the tubes one by one. My dad, who has built a few Weber kits, is trying to diagnose the problem but he's requested the factory (non-turret board) layout in addition to the schematic, which is how I found this thread. Anyone able to shed some light on what the problem might be or have the original layout? Thanks

Hi,
I don't have this amp, but that sounds like a loose connection,
when it vibrates the sound cuts out, when you turn the pot it moves what cables and it works again. Check for loose solder joints.

or it's a loose resistor to ground, probably in the signal line, when you move the pot back it discharges.
I had a similar problem with an amp build, and it happened because I forgot that resistor to ground, it played until the coupling capacitor charged, something like 3 to 5 seconds and after that it stopped.

Maybe it just needs a new pot, if this amp is old, you also need to change the capacitors, as they are probably out of specs.

Cheers
Thoma

Hi!

In the schematic the tone control is floating in plate voltage. I'm always a bit cautious when introducing high voltage to pots.

One solution would be to move the control after the coupling cap but would that introduce a variable high pass filter in the signal path? Are any other (simple) ways to make this thing safer without affecting the sound?

Thanks
Jouni

Hi!,
finished my supro clone yesterday!
Thanks for the layout by the way, it was really helpful!
I changed some things, with diode rectification, an extra RC filter stage, bigger capacitors, and changed the tone cap position to block the HV (I saw this somewhere, now it is between HV and the tone pot, while the tone pot goes to ground)
some pictures:
the rendered version:


and final version:







and my faceplate:
https://www.dropbox.com/s/5fuenprl4st84 ... e.pdf?dl=0

cheers,
Thomas