Wednesday, May 25, 2011

Building a quick Brian-May-style treble booster on Veroboard

It was a friend's 44th birthday a while back, so I decided to make a quick pedal for him.

I'd been wanting to try out a Brian May treble booster based pedal for a while, and I found this one at

Veroboard is also known as stripboard or perf board, and looks something like this:

Whichever terminology you use, make sure you get a board with lines/strips of copper and NOT one that has each hole insulated from the next like this:

I like building circuits on Veroboard, since it’s simply a case of following the picture. You don’t even need to understand how circuits work (although it would obviously be helpful for trouble shooting).

Anyway, here are the simple steps to making a Veroboard pedal.

1. Cut your Veroboard to size (in my case 12x5, erm, holes).
EDIT: In hindsight it would have been better to make this 14x5 which would allow an extra hole either side of C1 to attach the wires to the tone switch. So learn from my mistake and make yours 14x5.

2. Now "cut" the tracks wherever you are instructed to do so (you are just cutting through the copper, not the whole board). In the case of this particular circuit, between the pins under R1, C1, R4, and R6. The result after cutting would look something like this:

3. Solder the components on. Note that the copper strips are on the underside of the board, and the soldering is just like when you get a pre-made circuit board. Here's what mine looks like after soldering. Please ignore the fact that I'd also added some cables before taking this photo.

4. Finally, you need to wire up the enclosure. This circuit was so simple that wiring up the enclosure was the hard bit. If you are unsure how to wire up a stomp box enclosure, then have a look at my blog post over here:

5. Here’s the finished result. I didn’t have any time to make the enclosure itself look good this time around. My apologies in advance for the silly name.

Veroboard is very cheap and there are a LOAD of good circuits out there that use it. Here's just one example of a site that has a few:

As you can see, the Veroboard layout is much easier to follow than trying to read a circuit diagram, kinda like reading guitar tabs when you can't read music.

Some of the projects don't even need you to cut any of the tracks.

This Brian-May-style treble booster was a very simple circuit to build and works extremely well. In fact I think I may build one for myself too.


Anonymous said...

How much did it cost for you?

AluminumFalcon said...

Did you use a DPDT on-on-on switch for the c1 mod or just a DPDT on-on? If the former, what kind of sound does that give you? Thanks!

stu said...

Hi AluminumFalcon. It's on-on-on. The middle position adds no extra filtering (well, apart from the capacitor that's already on the veroboard). It's the cleanest, brightest, and most like a treble booster. The other two positions offer a medium amount of filtering, which is pretty neutral and comes out at more like a volume boost, and a stronger filter, which actually comes off sounding like a bass boost. I love the middle switch position (treble boost), as I usually like a bright guitar sound. I'm also surprisingly happy with the bass boost position, although the medium filter is kinda.... unexciting. You could, of course, experiment a bit with the capacitor values to find the perfect amount of filtering for you.

AluminumFalcon said...

SO I built it to the vero specs, but I'm not getting any sound out of it! What transistor did you use? The gain knob increases the hiss of the signal, but I'm not getting any guitar signal through. The bypass works, as does the LED. Any help would be greatly appreciated.

stu said...

Hi AluminumFalcon. If the volume control is giving you hiss, then all I can tell you is that the problem is somewhere before the volume control. If you've double-checked all the wiring, make sure the transistor is wired up right (not all transistors have the same leg position). You did cut the tracks, right? I used a 2n5089, btw (I had some lying around). These are more or less the same specs as the recommended 2N5088, but with a little more gain. What are you using? If you can take some close up photos of your build, I'd be happy to look for any issues.

AluminumFaclon said...

I've posted a few pics there. There's 4 tracks right? I'm using a 2N5088.
Thanks so much for the help.

stu said...

Hi AluminumFaclon. I've posted on the thread over at Harmony Central.

tomo6314 said...

Im a little confused with the wires for the toggle switch...C1 straddles a wire goes at one end of the cap ?? the other seems to join the board at the cut ??..that dont seem to make it jus a switch wire from each end of the cap ??? did you fit wires and component in the holes ?? or did you just solder the wires to the legs ??

stu said...

Hi tomo6314,

Very good questions. The wires go to each side of the cap. It's just not drawn that well. There's also a bit of a lack of space to attach the wires themselves, and the veroboard could do with being a couple of holes longer to accommodate this. In the end I think I just soldered the wires flat onto the underside of the board. It's not very pro, but it did the job. Soldering them to the cap's legs would work too.

kevin said...

This is really cool, I'm gonna have to give it a shot sometime soon

Al said...

Really great build, I'm going to give it a go his week. But just one noob question, where does the ground wire go to? Just soldered onto the inside of the case somewhere?


stu said...

Hi Al,
Yes, that's correct. If you look closely at the photos, you'll see I soldered to the back of the pot (which makes electrical contact with the case). Usually, the negative of the input and output jacks touch the case in the same way, so this is another option. This time around I used jacks with plastic surrounds, so had to go with a different option, hence the pot.

Mc Huge said...

Hi and thanks for posting this. I built it today and I'm not getting any affected sound. I tried it with and without the circuit but there is no difference. Even turning the pot has no affect.
Any ideas?

stu said...

Hi Mc Huge. Is the LED coming on? Also, are you sure the switch isn't sitting at 90 degrees to what it should be? Apart from that all I can suggest is to check the wiring very, VERY carefully. It's almost always a simple error with one connection in the wrong place. If you want to take some clear close up photos of the top and bottom of the circuit board (and the switch) I'd be happy to have a look at them.

Mc Huge said...

Thanks for your reply Stu.
I haven't installed the switch or led yet as I'm trying the circuit out as its laid out in the original schematics. I plan to add them once the booster is working. I have noticed a lot of ground buzzing so I believe it could be the wiring. I will check it later and let you know.
Thanks again.

stu said...

Well that certainly helps narrow it down. Make sure you have joined all the grounds/earths together (input, circuit board and output). Still it doesn't explain the volume pot making no difference. Are you sure you haven't accidentally connected the wrong orange lead to the output? That's the only thing I can see that would explain totally bypassing the pot.

Mc Huge said...

Hi Stu
I've got the booster working! YAY! It was dodgy wiring. One thing I would like to do is have it powered via my 9v daisy leads rather than a battery. If this is possible, would I have to change the 100r resistor as I have tried it with a dc socket and it just buzzed like mad?
Thanks again

stu said...

Hey Paul, it should be possible and it shouldn't be buzzing. The only thing I can think is that the power supply is a little dodgy, or maybe something isn't grounded right (remember that the ground on a pedal power supply is generally on the centre pin rather than on the sleeve). Did you have a look at this post?

Mc Huge said...

Hi again Stu,
Its stopped working (albiet, it worked briefly)
I've decided to redo it but more spaced out on a veroboard but I was wondering what types of caps are you using? and do you have a picture of the circuit as you've built it as I'm sure my supplier hasn't given me the correct type of caps. For example, this is the 47uf that I was given..
Sorry to be a pain but I have a great big gap in my board waiting for this :)
Also, the negative coming from the board and going to the left lug of the pot. Is that joined to the rest of the earths??
Many thanks

Mc Huge said...

Right, I've rebuilt it but using parts from a better supplier and I have followed the build process to your examples on here and it sounds amazing but I'm still getting a buzz. All 4 grounds are soldered cleanly to the pot but I have noticed the buzzing disappears when the volume on the guitar is rolled off. I have tried various guitars, leads and amps but the result is the same. I have double checked the wiring but have found no faults. Also, from looking at other sites. connected to this, I have used a bc109c for a bit more gain. Do you think that may have anything to do with it? One other thing, I noticed your switch wiring differs to the "how to wire a stompbox" is there a reason for this?
Many thanks for your help and ive learnt a lot thanks to you :)

stu said...

Hi Paul.

I admire your patience! Sorry you're getting that buzz. The only times I've ever got something like that, it was from a badly screened guitar (I realise you've tried several here). The fact that you're upping the gain will make it all the more obvious, when usually it would've been hidden at normal levels. I don't know if maybe the bc109c is higher gain or something, but I do know that I'm not getting any noticable levels of buzz from mine. Do you have a 2N5088 or 2N5089 you can substitute?

As for my switch wiring, the only difference is that I have put the LED wiring in the middle "column" instead of on the right. It doesn't make any difference though and it's more to make it easier for the wires to get to where they need to go afterwards.

Can you try switching off other electrical devices in your room, like TVs/lighting, etc? I'm just wondering if you might be getting some electrical interference or something. Anyway, as mentioned previously, if you could take some close-up pictures of your circuit, I'd be more than happy to have a look. Don't give up whatever you do!

stu said...

Reading through these comments again I realise I made an error in my first comment. The tone switch is three position, double-pole. It's ON-OFF-ON, not ON-ON-ON. Sorry if that caused any confusion. Unfortunately I can't edit the comment, so have to correct it here.

Anonymous said...

Hi, thanks for the circuit. I can't get anyone in shops to help me spec the capacitors. You have only listed them in Farads but not their voltage, type, tolerance, and other features. No-one will help me guess and I can't read the text printed on the components on each photo. Would it be possible to specify details of each capacitor so I can order the same parts?

stu said...

Hi Justin,

Sorry, I can understand how this might be confusing at first.

Firstly, there are two main types of capacitors you need to be able to distinguish between: electrolytic, and everything else. Electrolytic are the ones you usually see with a + and - sign. They are also sometimes drawn on circuits as a straight line and a curved line instead of two straight lines.

In the case of this circuit, only C4 is electrolytic, although I see that it is not clearly labelled as such. In its case, the negative side would go to the ground track. The other (non-electrolytic) capacitors could be ceramic, mylar or some other material, and it really doesn't matter too much which one you get. Usually you just have to go with whatever you can source.

As for voltage, just get something higher than the highest voltage that might go through them. Since this is a 9V circuit, you'll be fine getting capacitors rated at 25V or above. It is never a problem if they are rated at a higher voltage, although they tend to take up more space.

Also, regarding tolerance, don't worry too much about that here. We're not working with components that have to be particularly precise.

I hope that answers your questions, but don't hesitate to let me know if you need more info.


Anonymous said...

hey man this is one of the best instructed builds ive ever seen but I have one question...what is that C6 and C5 on the first pic? in the digram it looks like one unit but it is listed in your components list as "C5 and C6". what are these parts?

stu said...

Thanks for the compliment.

C5 and C6 are soldered directly onto the tone switch (see the second last photo). The capacitor value sets the tone.

Anonymous said...

Hi, so I built the circuit and when switched on the only difference seems to be a huge volume and tone drop. The signal is still audible but not much. Any thoughts on what the problem might be?