Silicon Buzzarounds

[jrmy]

You have my interest !!!
Will this be available for ILFer?

From my understanding, digi2t is just posting schematics so builder forumites can make their own - digi2t doesn't usually build for other people, but he's always great about sharing the information so anyone can do it themselves.

I'm not good with a soldering iron, so I'm keeping tabs on this thread to get a schem that I can pass on to someone who could build one for me.

I have to say, I get super excited whenever I see that digi2t has posted something new...

[digi2t]

Well, I've experimented with some low gain NOS 2N3567/8/9 button heads, and with and without piggybacking, the results are not great. I don't get the same texture as the Ge version, or sustain, as with the silicon PNP version that was on the breadboard before. Since the 2N2904/5 combo worked so well, I'm going to try with their NPN counterparts, 2N2218/9. I don't have any on hand, but my local shop has them, so I'm going to try to zip down there after work to pick them up. I should have some results this weekend.

If the perform as well as the PNP counterparts, I'll do another sound clip. Just fyi, the previous sound clip was direct into a Boss BR-600 recorder, with a touch of reverb, using the Roland JC-120 amp model.

I have to say, I get super excited whenever I see that digi2t has posted something new...

Well, with kind words such as those, I might just build one for you if this experiment works.

[Gone Fission]

There is one of the modern Roger Mayer fuzzes on tagboardeffects that's PNP Si that people tried to do NPN but couldn't quite nail down for whatever reason. That kinda thing is way beyond me of the why, but not unheard of.

[jrmy]

Well, with kind words such as those, I might just build one for you if this experiment works.

DON'T TOY WITH MY EMOTIONS!!!!!

[digi2t]

YO YO YO!!! Houston... we have lift off!

The 2N2218A and 2N2219A's did the trick. The gains are slightly different than the PNP counterparts, but in the same ballpark. I don't know what it is about these metal can transistors, but they seem to work really well, PNP, or NPN. Circuit still works best with the piggyback transistor, it adds a lot of sustain. If I pull it, it turns into a more buzzy Velcro gatey sound, so the option switch is still there. Pulling the 120K resistor from Q4 helps make it a bit gutsier (crunchier?), but the cleanup factor is still there, like the PNP version. One less part in the inventory. Small changes in the voltages here and there, but overall, pretty damn close. Without the 473 cap parallel to the diode, I put it close to the Buzzaround. The cap cuts a bit of top end, especially with single coils, giving it a touch of Muff edge.

I'll get a clip out soon, as well as an updated schematic.

[univalve]

Hot!

[digi2t]

Here is the recording. Balance is at max, Timbre at 1 o'clock. Same set up as before, straight into a BR-600, JC-120 amp setting, slight reverb.

It starts with the Sustain at 9 o'clock, then noon, and finally at max. At each stage, I vary between single coil bridge, bridge/middle (for a humbucker feel), and single coil neck.

http://www.soundclick.com/player/single ... 75245&q=hi

or download at;

http://www.soundclick.com/util/download ... D=13075245

This is almost the same layout as the PNP version. The transistors are 2N2219A in Q1/Q2, and 2N2218A in Q3/Q4. Slight changes in resistances, no cap parallel to the diode. No cap makes it a bit buzzier, which really comes through at max sustain. With the cap, it's got more of a Muff growl. Placing a rotary switch with several caps here could be an option for several textures. Disconnecting the piggybacked transistor adds another dimension as well. Easily incorporated into a vero.

Comments?

[goroth]

I know nothing about buzzarounds but I love how that sounds Dino!

[jrmy]

Nice! Love the raunch early on. What did you do around the 1:40 mark? Sounds like you let the beastie out of the cage.

Great stuff all the way through. Classic sounds...

[digi2t]

I know nothing about buzzarounds but I love how that sounds Dino!

Thanks! I'm definately going to build this.

Nice! Love the raunch early on. What did you do around the 1:40 mark? Sounds like you let the beastie out of the cage.

Great stuff all the way through. Classic sounds...

Yup, after 1:40 that's it flatout on all cylinders. I have a vero just about complete, and the schematic should be finalized later today. I toyed with it some more today, and it sounds even better. From 75% on up, the decay has these sweet harmonics that come out of nowhere, and that's through headphones, so no cranked amp shenanigans going on there. Reminds me a bit of a well tuned Harmonic Percolator decay.

I think I'm going to call it the "4 Banger". Although it's based on the Buzzaround topology, It's not close enough to say "Silicon Buzzaround", or anything like that. It's definately got it's own mojo goin' on. I'll probably go with a 3 cap selector for the cap parallel to the diode, bright, medium, dark attack sorta deal. Still up in the air on the buzz/gate on/off switch. I still need to find the right resistor for that, to simplify the switching.

Hey, did your earlier post get nixed by the admin? Anywho, Let me get everything into concrete, and if you want one, just PM me and we can talk turkey. You started me on this whole journey, so I figure you deserve a shot at a Hen's Tooth Cafe build.

[KaosCill8r]

Maybe you can build some of these 4 bangers for sale. Or maybe sell kits. I would buy a kit.

[jrmy]

That is awesome on all fronts! I deleted that post - I had meant it to be a PM, and posted by mistake. D'oh! I'll drop you a PM properly later today!

[digi2t]

Here is the final schematic;



Working on the vero right now.

UPDATE...

Here you go;



I still believe a 4 position rotary switch for the diode cap (C9) would be the cat's ass. Call it "ATTACK", and the positions could be "None", "Light", "Medium", and "Dark". No cap for "None", 0.047uF for "Light", 0.1uF for "Medium", and 0.22uf for "Dark", is what I would go with, but you can personalize that. I you decide to go the rotary way, remove C9, mount all your caps on a 4 position rotary, tap off Sustain 2 for the switch common, and a wire from the rail below Balance 3 can be used as the ground for all the caps on the switch.

This is going to get built this week. They'll be a Hen's Tooth Café video if it makes the final grade.

[digi2t]

Board is populated,





I did a quick test....
AND IT FREAKIN' ROCKS!!

Responds very well to guitar volume roll back, cleaning up quite nicely. Flat out, it just rips. The Timbre pot retain volume, and varies between crisper top end, or beefier midrange. The Balance pot works well as an output control. I didn't install C9 on the board since I plan on using a 4 position rotary, and installing all my caps on that. All in all, it covers a lot of territory.

As soon as it's boxed, I'll do another demo video.

[Chankgeez]