Another DIY pedal

ralley

Thought I'd show off my latest build. It's a clone of the famed SHO booster. Had to try this one out since the "boutique" pedal fans rave about this and yet it is so simple. Originally built this back in June with a 2N7000 FET substituted for the original BS170 (couldn't get that in SA). I was severely underwhelmed, didn't seem to do anything. Well yesterday the urge struck again and I had another look at it, realised that though both FET's have a D-G-S pinout the 2N7000 is rotated through 180 degrees. After fixing that and trying a couple of different FET's I found one that sounds brilliant ?.

Now that I'm in NZ I can get hold of BS170's so I'll try some of those as well and see which I prefer. Once I finish unpacking I'll compare this to the Sparkle Boost I built and which I prefer. Total cost so far for this is probably R50 in parts. Adding a case and switch will bump that up quite alot but it's still gotta come in way cheaper than the original at ~$300.

Here's the gut shots:

Manfred-Klose

How would you describe the sound it produces?

Do you have the schematics for that?

ralley

I'm not great at describing sounds but it's a boost that goes into light overdrive territory great for old style hard rock (my favourite) check harmony central for the usual overblown cork sniffing reviews using lots of wanky terms! It's a clone of a ZVex Super Hard On (SHO) which in itself is apparently a clone of a preamp from an old mixing board.

Schematic and the vero layout I used are both available on the forum at diystompboxes. Note that there are two versions of this scheme - they only differ in terms of the protection for the FET. Oh and if you stick 3 of them in series you've got a box of rock apparently.

Manfred-Klose

Cool i'll go check it out.

JoeyBones

Excellent Ralley. Hope you're enjoying NZ.

I was also quite bemused when I opened my Box Of rock to see what they heck I paid R2k for. These boutique pedals prove that less is more and Rob has proven that you don't have to pay more to get more ?

Any chance of getting me a schematic for a Ross/Keeley compressor ?

ralley

Hiya Joey,
Auckland is cool - but I'm still jobless which is a bit scary. Not much military avionics work here (i.e. NONE)

Schematics for the Ross are available here:

http://fuzzcentral.ssguitar.com/ross.php and
http://www.geofex.com/schemata.htm

Also BYOC has a kit for the 5 Knob Compressor based on the Ross:
http://www.buildyourownclone.com/5knobcompressor.html

General Guitar Gadgets also have a PCB available or you can etch one yourself from their layout:

http://www.generalguitargadgets.com/index.php?option=com_content&task=view&id=79&Itemid=26

By the way General Guitar Gadgets also have the BSIAB II (Brown Sound In A Box), thought by many to be a better sounding altenative to the drive section of the Box Of Rock. I'm currently building one and am going to pair it with a Sparkle Boost as an alternative to the BOR.

Rob.

ralley

...the building continues, got my 3PDT switches from Effects Connection (6 days to ship from the US to NZ, not bad). In a burst of inspiration I added the off board wiring to a Distortion Plus clone I built. This is from my first batch of PCBs that I etched and in another first it worked first time. It's noisy as hell but that's probably due to the lack of case, long wiring and wrong pots (just for testing).

Next up, finish my Rat clone - just needs a cap and some off board wiring:

Rob.

Manfred-Klose

Wow you suprised me once again.

Do you make the PCB's yourself, How do you do it? It looks alot neater than the pcb with the holes in it.

ralley

Hey Manfred, yeah made those PCB's myself. The process is actually pretty simple:

Print layout on inkjet photo paper using a laser printer
Iron the printout onto a piece of blank PCB, around 3 minutes with a normal clothes iron
Etch in a mix of hydrocholic acid (pool acid) and hydrogen peroxide (from the chemist), again about 3 minutes
Drill holes

Try it, it's easy.

Manfred-Klose

Thanks, that was the answer i was looking for.

I am going to learn auto cad, so i can design the PCB layout from a schematic.

What would suggest would be a fun pedal to start with for a first project.
Maby a classic distorion pedal?

ralley

Manfred, don't need to go as fancy as autocad for layouts, there are heaps of PCB layouts freely available. If you do decide to do your own layouts then some guys use basic paint programs or diy layout creator is a simple free program for vero, perf or PCB layouts.

For a first project a fuzz face is always popular, really simple and parts (for a silicon version) are easily available in South Africa from Yebo electronics. Other good starts would be the MXR Distortion+ or DOD OD250 (same circuit, slightly different component values), Rat, Big Muff Pi, Tube screamer.

Only part you will battle with in SA is the switches - 3PDTs are not available locally. I was using 2PDTs from Yebo but that requires a seperate circuit (Millenium bypass) to use a LED and true bypass. Unfortunately the 2PDTs arent great quality, plus I bought all of Yebo's stock before I left. Effects connection in the US currently have 3PDTs on special at $3.75 each and shipping (at least to NZ) was reasonable and fast.

Rob.

Manfred-Klose

I build the MXR DIstorion+, but yebo gave me the wrong switch, no wonder it didn't work right.

Is there PCB layouts on Diystompboxes.com?

Manfred-Klose

Will these switces work for an on/off operation?
Kind of like the way boss switches work, that is what i am going for. Just need to build the damn stompbox so it will function in that way.

http://www.fort777.co.za/index.php?main_page=product_info&products_id=2349

ralley

Manfred, if you want to do Boss style switching you will need to add extra circuitry for this. Still not sure whether the switch you linked to (SPST) would work, normally pedals use either DPDT or 3PDT. Also that switch definitely wouldn't stand p to stompbox use (stomp is the key word).

The switches I've used are: http://www.fort777.co.za/index.php?main_page=product_info&cPath=269_270_438_440&products_id=2297. I see they are still out of stock and as I said they are not the best quality - I've got to replace the one in my fuzz face.

At a push you can use something like: http://www.fort777.co.za/index.php?main_page=product_info&products_id=2353 for prototyping etc. but these are for hand use rather that foot switching. You can find equivalents to these at hardware stores.

Manfred-Klose

I tried that switch i got from yebo, But doesn't work for on/off config, if you want it on you have to keep it pressed down.

ralley

Ah that means you've got a momentary switch instead of a latching - beware because they look identical, the differences are internal.

Manfred-Klose

Next time i'll get the right stuff, learning from experience.

Is there any other way of switching, besides 3DPT?

ralley

Switching options that I know of are:

- SPDT (I think) with some sort of logic (FET etc) ala Boss etc.
- DPDT for true bypass, LED possible with Millenium bypass circuitry
- 3PDT for true bypass with LED

Manfred-Klose

I have have decided on a MXR Distortion+.

I found out last night that the schematic i used was the wrong one, thats why it didn'y work.
From now on i'll just use diystompboxes.com, they seem to be the correct schematics.

ralley

Cool, that's what I've just built so we can compare notes, I used the PCB layout from general guitar gadgets so that's confirmed as working. One thing to watch for - the original used a 1 Meg reverse log pot for the drive - you won't find this in RSA. Instead you can use a linear pot of a lot lower value, I'm going to try a 50k linear. I initially tested with a 1M linear and all the drive was in an absolutely tiny part of the pot rotation.

Check this thread for a discussion on the pots:

http://www.diystompboxes.com/smfforum/index.php?topic=67765.msg540619#msg540619

Rob