[NEW LAYOUT] Doug Hammond's Hot Silicon on Vero

[ulysses]

Doug Hammond's Hot Silicon on Vero is now in my gallery.

really nice sounding circuit - thanks to doug and those that put in the work prior, aron, gus, whever invented the tb

cheers
ulysses

[96ecss]

It really is a great sounding pedal. I have a pcb layout for it in my gallery if anyone is interested.

Dave

[alfafalfa]

I am interested in the pcb design . Could I have a copy ? I'll send you a pm.

Thanks , Alf



No need , I found it already !!

[96ecss]

Hi Alf,

It's a really easy build and sounds great. Please let me know if you build it and how you like the layout. I have a newer improved layout for it but I haven't posted it because it's not tested yet. I could email it to you if you like.

Dave

[DougH]

Doug Hammond's Hot Silicon on Vero is now in my gallery.

Nice, thanks!

[Gus]

The layout and wiring might take some work because of the gain of the circuit, X10 gain then a Si FF type Fuzz.
  Short wires,  input and output wires at 90 degrees if possible in they are close to each other.

Test it in a metal box, open air breadboard it might have problems.

[Dragonfly]

The layout and wiring might take some work because of the gain of the circuit, X10 gain then a Si FF type Fuzz.
  Short wires,  input and output wires at 90 degrees if possible in they are close to each other.

Test it in a metal box, open air breadboard it might have problems.

These are good "rules / guidelines" for ANY high gain circuit.

[96ecss]

The layout and wiring might take some work because of the gain of the circuit, X10 gain then a Si FF type Fuzz.
  Short wires,  input and output wires at 90 degrees if possible in they are close to each other.

Test it in a metal box, open air breadboard it might have problems.

These are good "rules / guidelines" for ANY high gain circuit.

I agree, these are good rules for any high gain circuit, but I've built about 7 or 8 high gain pedals (Blackfire, Vulcan, Obsidian etc) and I've only ever had problems once. It was with Aron's Booster 2.5. Oscillation on test board, sounded fine when boxed up.

I've built 2 of these Hot Silicon's and tested them both on my test board with no problems at all. Great sounding pedal, I use it way more than my GE Tone Bender.

Dave

[Dragonfly]

I want to take a second to point something out....

The other day (Yesterday ) Ulysses posted a thread asking if anyone had done a vero for the Hot Silicon. When he got no response to that thread, he took it upon himself to make a vero layout for it.

I just wanted to say "thank you " Ulysses, for providing a good example. If the vero was available, there was no sense in "re-doing" it...but it wasn't, and instead of asking a forum member to do the work for him (something which is incredibly common here...), he did it himself.''


So Thank You !

[ulysses]

The layout and wiring might take some work because of the gain of the circuit, X10 gain then a Si FF type Fuzz.
  Short wires,  input and output wires at 90 degrees if possible in they are close to each other.

Test it in a metal box, open air breadboard it might have problems.

i used 2n5088's instead of 89's because i didnt have any 89's, and also becasue i was also interested in not so much gain. if the 88's were not strong enough i was going to swap them out, but i really like them. i was able to dial in some page tones pretty quickly.

i read a thread by JHS (if i remember correctly) last week saying the TB circuit was designed for lower hfe trannies than were used in later models. i thought the TB i built (with 70/70/140hfe ge trannies) was too full on so i was interested to try a silicon version with lower gain si trannies.

i did not have any problems with it in relation to noise in or out of the box.

i was able to pick up radio moscow while testing out of the box with the gain all the way up with no guitar plugged in. as soon as i plugged my guitar in radio moscow dissapeared. each of my wires off the board was approx 5cm long and i used a 3PDT switch using the input grounded method (see my gallery for pictures of my wiring method).

the sound is excellent, its the original tb sound i have been looking for.

cheers

[Gus]

Some background

The input gain part is set up for about X10 gain with most Si transistors one might use and the output resistance of that stage was thought about as part of the gain setting of Q1 and the feedback resistor in a FF type circuit, like the following stage is.   You might notice it is a lot like the the Si type FF type gain stage I like to use 3 tran and others.

Now people might like this Si first stage followed by a Ge FF or.

[idlechatterbox]

Built and working. The vero layout is 1st rate Ulysses, thanks, and nice circuit D Hammond. I used 2n2222s, but plan to try other trannies later. Haven't caught any broadcasts from Moscow (yet), but if I do, I'll be sure and tie myself to the mast of a nearby ship... just in case.   

[DougH]

i used 2n5088's instead of 89's

I don't think it makes much difference, honestly. And I can vouch for 2n2222's in general although I haven't tried them in this circuit. I would suggest trying a number of different transistor types, hfe, etc while breadboarding and pick the ones you like the best.

[DougH]

Another suggestion- I usually run the gain from 75%-90% because it gets pretty hissy with it maxed out. A way to avoid that might be to put a small, fixed limiting resistor in series with C4. I'm guessing 100-500 ohm might help there if that's an issue for you.

Gus did a good job tuning the stage gains in this one. Also don't be afraid to turn the gain down. There are a lot of nice sounds in it. This is my favorite fuzz.

[idlechatterbox]

Gus did a good job tuning the stage gains in this one. Also don't be afraid to turn the gain down. There are a lot of nice sounds in it. This is my favorite fuzz.

Agreed. I was going to say something about that, but wasn't sure if it was something that I did wrong in my build. With the gain knob all the way down, or close to it, it really mellows out the tone of the guitar.

I also found that a pre-amp in front of the pedal sort of gets rid of the clipping tendency if the gain is cranked. Not sure if that's supposed to happen; maybe the pedal is expecting more signal than the single coils are putting out? Either way, sounds good. Almost like a combination between a fuzz and a pitch shifter, if that's possible. Cool 

[DougH]

Here's a sound clip for reference: http://www.aronnelson.com/gallery/main.php/v/DougH/hotsi/HotSi.mp3.html

Fat switch turned on at 00:50.