Couldn't sleep tonight so I went looking for the other better schematic. The dual opamp drawing is the one I still use. I think it's the same as the Yamaha without the switching. I also made a few without the buffer at the end too. Just took the output from the 100k volume. That sounded really good ...

This is the basic layout I used to make mine and a few for friends ..not a circuit board. I used perfboard and eyelets because I'm more of an amp guy and I'm more used to doing things this way. As I made them I changed it a bit but you can get the idea. I also did use the buffered output for the byp...

I'm dealing with the fires in Santa Cruz mountains right now ...but I did grab most of my schematics and stuff so I didn't have the time to redraw this but here's my drawing from years ago. This should be close. I do have a better schematic but couldn't find it. I have the layout for the one I made ...

I also love this pedal. It's been my TS killer...haha. I drew a schematic a long time ago and built a version of my own in 91. I'll try to find it..it's been years...but it's basically a buffer ..opamp with clipping diodes in the feedback.. 100k gain pot in the loop also..into a big muff style tone ...

bajaman wrote: ↑18 Aug 2020, 09:05 very M.E.S.A like

More just straight up Fender style amp with reverb with some extra options just for switching the tone of the amp a bit. Even the master and phase inverter is very 70s Fender. No extra gain stage like the Boogie MK1 amps....looks like a Boogie tho...

...I wonder if with the Baxandall transistors based there was an easy mod to create a mid bump or a mid cut without adding another band. Maybe is not possible. You could experiment with switching in a larger cap in parallel with the lug3 treble pot capacitor to give a mid boost: tone-stack-mid-boos...

Click on the pic ...it will open a higher resolution pic so you can see it much better and you can easily see the values. At least it worked for me...actually very clear and easy to read ...and I'm using my phone...

gght wrote: ↑07 Jun 2020, 06:18 Gut shot. Upper right looks like diode and transistor feed back loop??


https://toy-love.hatenablog.com/entry/2 ... 1397135083

Says in the description that it is like the real circuit found in the amp !?!? I didn't know the Dumble amp circuit was a hi voltage tube screamer

That resistor labeled 98k in red in that pic, is an 18k resistor not 98k. Besides the 47k in parallel with the level pot, it does match that schematic from Vox.

This goof recently took apart ..."to fix"...haha ...one of those Vox mini amps with the nutube. It's hard to watch. In the end he blamed the manufacturer for his inability to fix it. If you try to give him any constructive criticism or help in the comments, he just deletes it. The guy anno...

i think ..the other transistor is for the power supply. To protect it from a wrong adapter being plugged in. Nah, one of the bottom diodes is used for reverse polarity protection. 4th transistor is just for led indication. [ Image ] [ Image ] But then look at the assembly picture: 4 transistors :sh...

i think ..the other transistor is for the power supply. To protect it from a wrong adapter being plugged in.

Sorry for all the posts :o I checked the photo and the tone stack does appear to be wired Fender style. So the schematic is correct. I wonder why they went that way instead of like the real amp... I think i'll try the other configuration anyway to see how it sounds I don't know if someone has point...

I tried again with power to house off, but this time with my new EMF meter. So with power completely off there is no EMF showing up on the meter throughout the house. I then walked around with my guitar and iPhone with Bias app (no AC power). And I was getting (2) areas with noise. By the AC panel,...

The sweep pot is just changing the mixing resistor in the tone stack. I found this thread that still has the schematics up so that may help you with this circuit.

http://guitar-fx-layouts.42897.x6.nabbl ... 14828.html

That's odd, doesn't even make any sense. Did they give you a reason for the power tubes causing this?? I don't see the relationship to the channel switching to the power tubes. Unless it's heat related maybe...it's just odd but cool it fixed it. It's actually a cool amp once you figure out how to di...

Well... this is more of a line 6 product. Line 6 asked Reinhold to design and also licence his name for the product but Bogner had nothing to do with building it or much else...so the guys at Bogner wouldn't really know about problems or repairs of it. But cool you got worked out!! What was the fix ...

The power tubes have nothing to do with the channel switching. Could be anything from dirty jacks to something wrong with the switching power supply....or a bad solder point somewhere. With the amp on ...poke around with a chopstick or something like that and see if you get anything to happen. There...

good day i traced my amp tonestack and i found this check below pic..when i turned down the all knobs to zero the output signal of my amp lost i mean no output at the speaker..is there a problem in the components of this tone stack?? when i turn up the knobs again the signal came back..??sorry my a...

underwood wrote:What are R15 and R17 for? No Capacitor vor IC1B? C3 is a little small. No RC-Filter in the supply!

D3????

He's just posting a basic idea from looking inside one.....not something that is verified