Modded Bazz fuss build

[Widows]

Hi folks, I'm currently playing around with a Bazz Fuss layout that I've been modding. It's based on a layout I found in another post by Nocentelli (see below):


I've drawn out a schematic, breadboarded it (sounds great) and have just put together a layout on DIY Layout Creator and was wondering if any of you folks out there would be kind enough to cast your eye over it n see if there's anything I've missed/got wrong.

Schematic:


Layout:




As you can see it's a modified single knob Bazz Fuss using a Darlington Pair configuration of 2N5088s, switchable tone stage on a DPDT toggle switch, and switchable clipping diodes (2x1N914 / 2xRed 5mm LED) on a 3PDT stomp switch that effectively acts as a booster given that LEDs put out a fair bit more than silicon diodes.

I'm particularly interested in the following:
- If I've got things right with the switches.
- How to add a status indicator LED that illuminates when the LEDs in the clipping stage are engaged
- Any improvements I could make to the layout to make the board more compact

I'm fairly certain about the schematic but I'm not 100% on the layout. Apologies if the layout is a bit messy, it's my first go at using the program. Any advice will be much appreciated.

Thanks

[nocentelli]

The way it's drawn, it looks like your diode switch shorts base to collector in either throw with ther middle column of lugs - I think maybe you need to rotate the switch 90 degrees or something.

I'd be inclined to simplfy the input cap switch by having the small cap permanently connected to the base, and just add the larger cap in parallel with a SPST switch - two wires versus six. And you won't hear a difference apart from less risk of popping.

I've not tried back to back diodes in the bazzfuss, how does it sound?

[Widows]

Thanks man, the back to back diodes sound pretty good in a Bazz Fuss especially if you use LEDs - you get a really nice thick fuzz sound especially when using both pickups on my SG. The biggest improvement in sound was using the Darlington configuration though, until recently I was using an old Bazz Fuss build with just a single 5088 transistor which sounded good but gated pretty quickly. Will check out your advice with the diode n cap switches and post up when I've got some results, in the meantime, thanks for the original layout design man 

[Widows]

ok I've edited it slightly.



Changes made:
Moved the yellow wire from the cap switch to base of Q1, it was on emitter in the last drawing - my mistake.
Put the caps directly on the lugs of the toggle switch thus saving space on the board and reducing the number of wires needed.
Swapped the 3PDT diode switch for a DPDT switch and adjusted the wiring of the switch to suit DPDT.

Does this look a bit more together now?

Also, how would I add an LED status indicator that lights up when the switch activates the LEDs in the clipping stage? It's not totally necessary but it'd be nice to have the indicator there if I could.

Cheers

[nocentelli]

That looks fine, I didn't spot the base/emitter error either. For an LED to show LEDs engaged, you need a 3PDT, wire the first two columns as per your current DPDT, then run ground to the common (central) lug of the end column, then connect the upper right lug to the LED negative, then LED positive to a suitable current-limiting resistor (e.g. 1-15k) then connect the other end of this resistor to +9v. Leave the bottom right lug of the switch unconnected.

Thanks for bumping this with your schematic. I can't believe I haven't tried the bazzfuzz with a back-to-back diode or LED pair before, it sounds great. I've just spend 30 minutes straight bashing out dirty fuzz solos and even filthier riffs - Much better than I remember it. The back-to-back diodes versus single c-b diode is a subtle but definite improvement, and the LED boost is certainly a boost.

I've used a 50k series tone pot where you have "murk" but leading to a 3n3 to ground and a 100kA volume pot lug 3, lug 2 output, lug 1 ground. The murk now controls a nice range of treble roll-off from just too murky, to "wow, that's bright!". I thought your murk was intended as a tone control on your schematic originally, since it implies the output is taken from lug 1+2 together, whereas your latest vero has it as a standard voltage divider output control with the output taken from lug 2 and volume 1 grounded. The input cap switch gives a nice bass roll off if you have the tone control rolled back to even things out a bit. I also swapped the back-to-back diode pair for two parallel pairs in series: The extra compression/less headroom from the diodes is still there, but with tiny a bit less filth, and more output.

Going to keep tinkering. Thanks again.

[Widows]

Awesome thanks for the help and the comments mate. Glad you're having fun with it   Yeah the LEDs definitely make you sit up and take notice haha, that's why I dubbed it the "Holy Crap" switch haha. I'll get that all wired up in the next couple days and see if I can get some sound clips posted. Just waiting for my uni-bit to arrive so I can get it in my new pillar drill n make the box up for it too.

I've redrawn it as per your comment above, check it out:



pics/clips etc to follow at some point soon

[Widows]

ok, I've noticed a mistake in that layout above. There needs to be a cut between the yellow wire from the 3PDT switch and the jumper leading to the rail above, without that cut it would short the diodes. However, it's not really necessary as in reality i was just able to bend the collector leg of Q2 to connect directly to the same rail as the collector on Q1 and so eliminating the need for that little jumper next to Q2. I only put it in there as I haven't figured out how to do what I just descrobed in the program itself, yet.

After having the circuit prototyped on a breadboard for ages, I finally finished the circuit build on vero today and got it hooked up to a breakout box and a little 10w solid state practice amp that I have on my desk for testing. This thing sounds huge, even on that little piece of crap amp! I'm going to mark out the box for drilling next and get the thing boxed up properly. Looking forwards to sharing the results with you.

[Widows]

Hey folks! After a long wait I've finally got this finished and boxed up. Check 'er out:











Thanks for all your help on this guys, I really appreciate it and have learned a fair bit from this project alone!
I'll try and get some sound/vid clips of this thing in action.

Just got to buy a knob for this now, and once I post this, that's exactly what I'm going to go and do