Another silly dual-stage overdrive

[ElectricDruid]

Now available at a Github near you: https://github.com/rockola/wattbreaker

Nice work. I like to see a schematic where someone took the trouble to put the relevant LP/HP cutoff frequencies in the places where they occur. There are usually several key components that shape the tone in a circuit, but often the schematic neglects to say where/what they are and what they do. I suppose that's not surprising on commercial designs, but it happens a lot on DIY stuff too. Fill us in! We want to know! Your version of Mark's schematic does that very nicely, so thanks both.

[r080]

Mark,

Would you consider changing it to Another Silly Bi-stage Overdrive (ASBO), in keeping with some of the discussion here?

[287m]

I love dual clipping, perf-ed this. Waiting for pots. Didnt have any in stash.
Thanks Mark!

[Shoeman]

Just finished breadboarding this with a 4559, and it seems a useful pedal.  Different from my TS and OD1 clones for sure.  At the risk of sounding cork snifferish I'd like to try it with a TL072 as originally designed.  Time to hunt some down. 
Took a bit of fiddling but once I got it fired up, my fingers did one of those subconscious things and Rocky Mountain Way's main riff spilled out and the sound brought a smile to my face.  Don't ya love how music and the mind work together without thought at times?
Thanks Mark.  You are always worth paying attention to.

[Mark Hammer]

Thanks, Geoff.  Very kind of you.
Sometimes a grilled cheese sandwich and  bowl of tomato soup are the best meal ever.  Simple things, done right, can be very pleasing.

[Steben]

Oh Dear haven't seen this one before 

Nice one Mark.
One of the main aspects with such a setup besides the recurring EQ story, is the ratio of treshold of first stage and second stage and gain.
Playing with these will give a clipping image compressed/harder or more loose/softer.
If using silicon diodes in the first stage it will bring a TS style signal into the BB soft clipper. This will yield roughly a 1.2V + 0.6V + multiplied original signal if no EQ is counted. These knee points do mimic somewhat the best tube power amp response. If LEDS are used in first stage it will be 1,2v +1,2v + multiplied original. Such a 1/1 knee ratio reminds me of an AC30 response. And surely some signal will be eventually hitting the opamp rail. But at highest gain this is not an obstacle since the onset of clipping is soft by design. Tube amps do clip hard eventually as well.
It is futile to say experimenting will be the work of the day.

[Shoeman]

I finished a perf board version a few weeks ago and after some poor solder joint debugging as it was my first perf, it's a great pedal.  It seems to have more bottom end to it than the other effects in my collection and has no annoying fizz, as designed.   I can get my homemade TS-9 to sound similar but it's not exactly the same.  Stack the TS-9 into a Ross compressor into the Wattbreaker and your guitars note will sing and ring for a LONG time. 
 

[Mark Hammer]

Thanks.  My own impression is that the TS-808/9 was originally guided by a desire to achieve relatively consistent distortion across the entire fingerboard, from the lowest E to the 22nd fret on the high E. string.  The Bluesbreaker aimed for a similar goal, with a slightly different tone.  It could be the smaller low-power amps I tend to play through, or the guitars I use, but I personally find that overall tone of limited appeal.  Gimme more bottom.  I can always use my picking hand to regulate how hard those low notes clip.  And if a person has a Reverend guitar with their Contour control, you can tailor the guitar's bass response.

I think that in the case of the Bluesbreaker-vs-Wattbreaker, the stock Bluesbreaker's use of diodes allows a bit more dynamics, whereas the Wattbreaker's use of clipping diodes in both stages provides a bit of compression, that lets you get whatever grind one wants out of the low strings, but without getting any intrusive volume peaks.  At least, that's what I think.