Industrial strength boost/drive/distorion

[Digger1770]

I picked up this industrial foot switch at the tip shop and thought it would make a good guitar pedal enclosure. All the hardware is fitted and I just need to finish the circuit! Boost/ drive/ distortion
The circuit is based on a ruby amp with a level control to attenuate the signal to line level. I added a bias circuit to the input buffer, a mod switch to go from Hi-watt to bassman mods, variable switch-able clipping on the output and gain/drive control. True bypass.
When in boost mode the gain is fixed to around 50 with volume and output level control. The Drive/dist mode can then be added to this allowing gain (40-200) and distortion control  with switching of positive and negative diodes to silicon or germanium or off position.
This circuit being a modified amp will happily drive a speaker to practice levels when the level pot is maxed.




Cheers Dave

[Digger1770]

This is the same circuit in an amp, still with level control so the circuit can be driven and clipped with adjustable output volume to the speaker or amp. Recycled red cedar, salvaged radiogram grill cloth, 1950's AWA speaker like new (re doped), hand built "Manhattan" circuit, polished and stamped control panel.




Cheers Dave

[vigilante397]

That is severely cool

[bluebunny]

It is indeed.  Nice bit of re-purposing.  I'm now imagining a similar arrangement using the pedals in a car.  Perhaps Mark C. might build such a thing into that project he has on his driveway?   

[Digger1770]

Made some progress on the circuit, using plenty of old components including hand painted nos germanium diodes (.25v ), and a nice old trim pot (bias).




Cheers Dave

[duck_arse]

Made some progress on the circuit, using plenty of old components including hand painted nos germanium diodes (.25v ), and a nice old trim pot (bias).


Cheers Dave

.... and some copper pipe. a jumbo philips trimpot, been a while since I saw one of them. and I thought your diodes were caps.

nice wood, as ever. you got any spare, send it my way, yes?

[Digger1770]

Sorry duck_arse, no spare diodes I only had 4 of these, the other 2 have different dots and a slightly higher forward voltage (zeener diodes?).
Anyway here is some more progress, just the power and foot switches to wire,in the base of the pedal.

Bent diode is now straight!
The copper coil is a heat sink for the 386, not really required but I think it looks ok and hides the IC a bit, I didn't have enough height to fit the V8 heat sink!


I will do a schematic of the circuit if it works!
Cheers Dave

[Digger1770]

Sorry if the pictures are too large I did resize ect but it looks like it didn't work properly.
Cheers Dave

[duck_arse]

never mind the bollocks diodes, it was the wood I was looking at, spares wise. and I think your pics are now too small.

most here would say, if you can't fit the V8, cut a bigger hole. I'd say that, too.

[Digger1770]

The timber for the amp?

If this is what you mean duck_arse its Aussie red cedar , I don't have any more of these second hand boards. I do have some rough sawn slabs of cedar (milled in the 60's near Maitland NSW) , and access to plenty of Tassie timbers. I am taking some guitar timbers with me from Hobart to Byron for a friend (black heart sasafras, celerytop pine and one piece of fidleback blackwood ) in three weeks, I am staying west on the way up (Junee, Gulgong, Tambar Springs,... and other great pubs along the way ) but will come back through Sydney in October. pm me if your looking anything.
Cheers Dave

[Digger1770]

Red cedar boards/slabs make great tool shelves,

The sasafras I can get.( ignore the prices or x10 if interested  )

The blackwood  ! I convinced a friend to part with a 1m board of this for a special guitar, he only has 350m so I didn't want to push it 

Huon pine slab with alot of birds eye, and I have some Macrocarpa (the darker slab)

No pics of the cellerytop pine as it is coming from the mill Tuesday.
If anyone is interested I have room on the roof racks for a few more boards and am charging cost plus some fuel money (Hobart-Grafton via west NSW , then Grafton-Hobart via Sydney and the south coast).
Cheers Dave

[Digger1770]

Just an update that the pedal is all working great with no major glitches.
here is a rough sketch of the circuit used.


The bassman/ highwatt switch works well  with polar opposites of tone from clean sharp sound of the treble (highwatt) to the thick muddy bass (Bassman).
My question on this is are there any obvious faults in a circuit that blends these mods as a tone control, other then the added resistance of the pot, such as this.
 
The 220pf cap is to retain highs.
I will test this myself but wont have time for a while.
Cheers Dave

[duck_arse]

diyd - if what I can see at the phucket is right (grrrrrrr), SW1 is going to pop like buggery each switch. hardwire the 220pF and the 15nF caps, switch the others in/out in parallel, maybe with a spdt. you probably need some bleed resistors there. also, your zobel resistor seems to be 10k, usually they are 10R. and wouldn't you have the clip/warp section between the scribble cap and the volume control?

[FuzzFanatic71]

Made some progress on the circuit, using plenty of old components including hand painted nos germanium diodes (.25v ), and a nice old trim pot (bias).




Cheers Dave

This thing is so awesome. Look forward to hearing it in action. There is just something magical about dirt pedals in "found" enclosures.

[Digger1770]

diyd - if what I can see at the phucket is right (grrrrrrr), SW1 is going to pop like buggery each switch. hardwire the 220pF and the 15nF caps, switch the others in/out in parallel, maybe with a spdt. you probably need some bleed resistors there. also, your zobel resistor seems to be 10k, usually they are 10R. and wouldn't you have the clip/warp section between the scribble cap and the volume control?

SW 1 doesn't seem to pop but I will make the changes you suggested as I should be able to just change on the swithback . Cheers!
Zobel is 10R sorry and before cap (sorry drawn off the top of my head)
I had the same thoughts on the clip section and have moved it to between the cap and level control, so after decoupling but before the signal is cut. It has a much better effect in this position thanks again.
Dave 

[Digger1770]

Changed the switch as suggested and it does sound better when switched. I also changed the position of the clipping takeoff and this too sounds better or less effected by the level control.
So its done now and when I find someone who can actually play well I will do a video.
Here is the set-up I made for the battery, 30 second change.
 



Cheers Dave

[vigilante397]

Again, severely cool stuff. Love these updates!