Generic Boost pedal parts

James · Post by **James** » Mon Jul 27, 2009 10:52 am

I'm tempted to whack in an order for parts to build some boost pedals and a looping/routing pedal. I have lots of resistors and caps so I doubt I'd need any of those, but I don't have a range of transistors. Looking at a few schems it seems a couple of BS170 ones would be useful, but what else should I pick up some of? At 12c or so each, I may as well spend a couple of quid and get a bit of variety.

Also are there generic pot values for these things? I know a lot are based on the same circuits so I imagine a lot of designs share pot values and tapers.

The order is basically going to be boxes, switches, jacks (audio and DC), some stripboard, LED stuff, pots and knobs and then transistors. I feel like I'm probably missing something out and it would be a right bastard to be a 12c component down and not be able to buy it easily in England.

Post by **Mike** » Mon Jul 27, 2009 10:59 am

BS170s, J201, MPF102, 2N5457s are all good MOSFETs for Boosts (SHO, AMZ MOSFET Boost etc)
2n5088, 2n3904 are good Bipolars (LPB-1, Saltbooster etc)

The SHO is odd as it uses a C5K (5K reverse log) but you can get away with a 5KB, LPB-1/Saltbooster use 100KA.

What other circuits are you going to play with?

Also if you forget anything I am happy to send you stuff, I have lots of spares.

But each booster will need this:

Case
3PDT
Audio Jacks x2
DC Jack
Stripboard
PCB Standoff/Foam Stickiers - can be got in the UK
Pot
Knob
LED & Bezel
Resistors/Caps
Wire

Maybe some togglies for Fat/Thin switches?

James · Post by **James** » Mon Jul 27, 2009 11:08 am

Is it sipmle to make a non-crackle SHO? I know people at FSB have done it but I don't understand how.

I'm not really sure what to build. Reading FSB yesterday I decided that I should build at least one AMZ type. I have two to build (well at least two) and I plan on rehousing the SaltBoost you built for me (into a Hammond A box) as a third unless you have a 'saltboost for bass' with more headroom or otherwise modified SaltBoost type that I could build from scratch.

To be honest I feel intimdated by it all. I realised that there's no reason I shouldn't build them. I know I have the capability to make sipmle circuits like this. I just have so little understanding of the basics that when I read 'just change the __ cap to a __ type' my mind goes blank. I pretty much need a complete vero diagram to accomplish anything and a lot of the boost stuff is made with the idea that the people building it will be able to create their own layout (vero or otherwise).

Post by **Mike** » Mon Jul 27, 2009 11:13 am

Just increase input and output caps to 1uF for a bass Saltbooster.

The gain control has been changed on the SHO to stop it Crackling in Soulsonics version, try that.

if you need pinpointing stuff on diagrams just ask, mate.

James · Post by **James** » Mon Jul 27, 2009 11:22 am

That SoulSonic guy (his avatar always reminds me of Nick, or that guy who used to post at JS and was very into Elliott Smith, Brian) is actually the one I was thinking of when I thought of getting rid of the crackle. Is there a diagram of his version? I never came across one reading about it.

Also...

James wrote: when I read 'just change the __ cap to a __ type' my mind goes blank.

Mike wrote:Just increase input and output caps to 1uF for a bass Saltbooster.

I might be able to notice which caps those are if I was looking a layout, but even the text scares me a little.

James · Post by **James** » Mon Jul 27, 2009 11:31 am

James wrote:I might be able to notice which caps those are if I was looking a layout

I suppose it's easier when there are only two caps. IF I changed those two to the value you said it would be better suited to bass? More headroom or just more low end?

Post by **Mike** » Mon Jul 27, 2009 12:13 pm

Yep. positive ends towards the input wire and transistor respectively.

I'll dig out Soulsonic's circuit and PM you, I'll draw you a vero layout for it also

James · Post by **James** » Tue Jul 28, 2009 4:38 pm

Parts ordered. Enough to do three mini-boosters and the bypass loop pedal I've mentioned before. Also ordered a few extra bits (purple jewel light for my vibrochamp, new pots for my jazz bass (crackle not okay) and the helping hands thing they do). I'm quite looking forward to getting stuck into this batch of pedals. Not looking forward to trying to accurately drill the mini boost cases.

timhulio · Post by **timhulio** » Wed Jul 29, 2009 7:42 am

James wrote:Not looking forward to trying to accurately drill the mini boost cases.

I do the layout for enclosures using Paint Shop Pro, then print paper templates to fold around the case, and drill pilot holes using a 2mm bit first. Quicker than marking the cases with pencil, but still accurate.

Post by **Mike** » Wed Jul 29, 2009 7:45 am

Yeah I use drill guides on paper these days, either made by Benecol or myself freehand from a template. Spend lots of time making sure everything will fit before drilling.

I masking tape mine to the case.

benecol · Post by **benecol** » Wed Jul 29, 2009 9:16 am

I'll rustle you up some drilling guides if you want, or send you mine so you can make your own, no problems.

James · Post by **James** » Wed Jul 29, 2009 12:18 pm

My plan was to cover the case with masking tape and then start with the switch. Work out the nearest I can get it to thebottom and mark that point (and a centre line for the whoel pedal) on the masking tape. Then go to one of the jacks, work out the nearest I can get it to the switch and the best way to orientate it and mark that, and then do the next switch. I'd probably put the jacks in (not screw them in, just place) and work out the pot and JC jack placement. I might try and od the LED straight after the switch. Something like that anyway.

I think it's safer to fit things that way rather than use a printout when space is so limited. Although I think I might go for a benecol/Mike style decal on it once they're drilled and I can see what space I have available. Benecol, perhaps a drilling guide/decal for by A/B loop pedal would be useful. It's the standard BB size. I need to sort the details in my head first though.

benecol · Post by **benecol** » Wed Jul 29, 2009 1:04 pm

The drilling guide's a piece of piss - just measure all the bits and I'll make you one up, loads easier than that convoluted making tape jive turkey.

Post by **Mike** » Wed Jul 29, 2009 1:16 pm

benecol wrote:The drilling guide's a piece of piss - just measure all the bits and I'll make you one up, loads easier than that convoluted making tape jive turkey.

Probably not.

That's the method I used to use and for one off crammed stuff it's very efficient, plus he doesn't have to wait until your spawn are asleep/not ill to make any progress.

benecol · Post by **benecol** » Wed Jul 29, 2009 1:18 pm

*gives pedal away in fit of pique*

Post by **Mike** » Wed Jul 29, 2009 1:19 pm

Pussy.

You do awesome work and I really, really, really appreciate it, but I know James has pockets of free time outside of shifts and the DIY method will allow him to make as much progress as possible in those windows of time.

James · Post by **James** » Wed Jul 29, 2009 1:22 pm

Outside of shifts? What shifts?!

Freetime til Doogfest, baby.

I was working nights this week but only the first two. Last night was my last and my machine wasn't running so I took a half shift to get home at 3am and get into a normal-ish sleeping pattern. I'm off work til the 12th (Wednesday after Doogfest) and then go back for Weds-Fri morning shift followed by a week of night shifts and then I'm off til the 7th. The 7th of Decemeber. Fuck yeah.

Post by **Mike** » Wed Jul 29, 2009 1:24 pm

Nice, well it makes even more sense then, as soon as you get your shit, you're going to want to rock the casbah

benecol · Post by **benecol** » Wed Jul 29, 2009 1:45 pm

The difference being, I'd prioritise James's.

James · Post by **James** » Wed Jul 29, 2009 1:47 pm

My plan was to go with the masking tape and pencil method and then to take some head on shots of the pedal with the parts installed, size them to scale in some graphics program and create some decals to print from those. Could you help me doing that, benecol? The boost ones won't have much detail just because of the size, but the looper will have plenty of blank space to try and do something interesting in.