Thursday, June 4, 2009

Build Report: Boss MT-2 Metal Zone

[While this blog was originally meant for digital electronics only, it will now include from, time to time, some analog stuff too. I think that I'm finally starting to love analog stuff...]

For those from (third world..?) countries where BOSS effects pedal are way, way, waaay too much overpriced for their poor, poor, sad, pedal-less self, this post might prove to be of some interest. Here's build report of the BOSS MT-2...the Metal Zone.

And Yes..With Pictures.
It all starts with this all-too-familiar packet from

I bet they cant wait to be mounted...

...on this locally made PCB.

Board overview, minus the op-amps...

Custom mounting techniques...

Verroboard for pots...(which had to be redone in the end)

Note: Expect this post to grow over time as I complete the pedal.


This one was a real b*tch to build. I had to change 2 full sets of op-amps(that means 8!), burning and lifting several PCB tracing in the solder/de-soldering process. Also, after a trillion hours of trouble shooting, I basically found out that some stages of the schematic I was using was WRONG(AAAAAAaaarrrgggh!!) [that was very precisely the exclamation I made when I found the error]

Nevertheless, after another trillion or so hours of troubleshooting, the pedal basically worked quite satisfactorily, except for that noisy background 'waterfall' sound that I tamed later. The palm-mutes it generated were 'chubby' and essentially had that character what I was looking for. There is still a significant amount of noise that comes out though and somehow, I feel this project is still not completed because of this. But it is very usable and for my second pedal, I think the cloning is quite a success. (I found out later that it is actually one of the most difficult pedals out there to clone )

I am currently drawing up a corrected schematic which I will post later(with the PCB layout).

Also, I will post sound clips some other time when I get to.

(Here's the cloned 'Boss Metal Zone MT-2' in late testing phase)


Allan said...

Well you saved my life , i was ready to make this project but if you say that pcb have some errors i surely wont try it.
Maybe if you have the corrected PCB and Layout it would be nice that you can post it here or maybe mail it to me.
Greetings from Peru.

whirlwings said...

no no, the pcb is perfect, so is the schematic. you just have to watch out those traces, some of them can easily mistaken as connected though it's not. always use shielded cables to eliminate the hum. i've recently build this one and it's perfect. just follow the schematic and you'll go fine.

Babak said...

I was just wondering if u can send post the corrected schematic or PCB please.

mAnis said...

"whirlwings" is right. Also, look out for the orientation of the transistors/fets when you are using substitutes.

The actual schematic is good. But the component placement that is suggested by the guy who had redrawn the PCB is incorrect.

Just pay attention to the original boss schematic when soldering and you will be fine.

Happy building,

Dipanjan Das said...

Hi.... I saw your board and the project board on that website. You have changed a few transistor positions and one particular transistor's one leg was connected to a resistance and grounded. I'm new in cloning world and need some help. Can you send me your corrected PCB design so that I can compare what I have to change. Another question.... In there website they have posted the sound clips they got from their project and they have the same transistor positions as shown in the pictures. My question they are getting the sound if the circuit is wrong?