The Amp Garage

It is great to have a readable schematic. I looked at yours and have some thoughts i would like to share. I think on the handdrawn schematic the feedback to the reverb mixer from the reverb transformer the comment is: 'to yel' not ' to PI' (bad handwriting), i think it is a reference to the yellow w...

I made a screenshot of the cathodefolower in the schematic

Richard, the McIntosh schematic you linked is where the Odyssey amps came from, it is not a CF (cathode follower, ie the signal is taken from the cathode of the second tube) as most SSS amps (which come from SVT), but it is a “plate follower”(ie the signal is taken from the plate of the second tube...

It is a solid way to lower the B+ on V7 Martin, but In my opinion a change in the applied anode voltage will result in a different perfomance of the tube and therefore will have some influence on the sound of the amplifier. (either good or bad) I think the transconductance and internal resistance of...

For the zenerdiode you selected: Going for a 5 watt zener is a bit over the top. It will probably work, but a zener needs to be at a correct bias. For it to work correctly there needs to be a minimum amount of current trough the zener. If you calculate the current trough the tube you will find 1,3 m...

Here some pictures of the filter switches. By coincidence i ordered CTS 11 position switches and i like how everything can be fitted on the switch. Also a picture of the PAB and midboost. They are mounted under the pots and switches to save space. (Thanks for the relay board Erwin) The other board i...

Congrats, Richard! Erwin and a few have been helping with the schematic fixes. I'm pretty confident about it and happy to adjust if anyone finds a problem. https://github.com/colganr/LTSpiceCircuits/blob/master/Dumble%20Steel%20String%20Singer%20sn002/SSS%20No%20002%20PDF%20Export.pdf As for the re...

Here are some pictures Erwin... https://i.postimg.cc/3y2G3LxS/20200827-225553.jpg https://i.postimg.cc/9rGHtZz3/20200827-230052.jpg https://i.postimg.cc/RqwvGjbb/20200827-210434.jpg https://i.postimg.cc/mPjY9psP/20200827-225527.jpg https://i.postimg.cc/gw6VnVG5/20200827-225516.jpg

Hi Ryan and Erwin, I finished mij build today and the amp is working great. I put in relay's for the preampboost, the fet and midboost. Next to great clean tones the amp has awesome overdrive too and this can be shaped very nicely by the filters. I used 10nF caps on the filter and to the level pot (...

Strange, with the 1M2 and 33K to ground the voltage of the second stage into the overdrive stage is divided by something like 37. So 37 volts in the 1M2 resistor gets you 1 volt out on the other side. I tryed it in my amp and mostly got clean sound exept with everything on 10. With the most used 220...

I see you are using a 1M2 with 33K to ground at the input of the overdrive tube. Even if the relay is working, your sound would still be clean when switched to overdrive. The input signal becomes too low with this resistor combo to produce any overdrive. Try 330K instead of 33K to ground to get some...

Thanks Rootz, It certainly is the best clean amp I ever played, the reverb is very good and enjoyable! It has a bit of a ducking effect, in the decay the verb gets louder! I might tweak the amp for more bass, even with a 4x12 cab, basically full bass now and I think it can use a bit more. Talked to...

Thanks, it's nice to hear you like the sound. I did not have the patience to cut the slide switshes, I had the chassis made to my specifications. It's laser cut. As soon as I have the time i will draw and post a schematic. All I have now is lot's of paper with different drawings, none of them realy ...

Hi, My name is Richard, I'm from Holland and have been reading on this forum for some time now. With information found here on this site and elsewhere on the internet I build a Dumble style clone in a Marshall like case. I thougt it would be nice to share my experience with the members on this Forum...