Hey there!
I've got an old Japanese Boss HM2.
I can remember the first time I gave it a try into a Marshall 100W solid state, I was very disappointed by its poor quality "too fuzzy" sound.
Since then, I bought a tube amp and it really sounds better in those kind of amp.
Though, the sound is not so transparent and it is still a little fuzzy so I assume there are some ways to improve it.
A friend of mine lend me his own hm2 modified from indyguitarist mods. I am really disappointed about these mods as the pedal reacts very strangely: the sound is brighter, more transparent with more bass (good points) but the distortion is no longer so heavy! It sounds like there is a noise gate that remove the attack of the note, and there is a kind of distortion veil that is very annoying.
So I first thought that my friend have done something wrong when modifying it, but apparently not as I've checked it.
I tried to change some of the diode clipping on mine, as it has been done on the modified hm2 and it sounds the same, very strange.
So I came back to original specs.
Now I have searched over the net and this forum for a valuable mod but I just can't find anything. There are some old topics here and there, but the schematics are no longer on the net.
Does anybody can help me?
One mod that I think improves the HM-2 is to locate the two Ge diodes sitting in-line with the signal after the feedback clipper stage and short them out. They're between two 10K resistors which makes them easy to spot. I shorted the diodes and one of the 10Ks and I like the sounds much better.
The big problem for me with the HM-2 is the tone control section. I can dial up all kinds of settings that I don't care for. I finally ended up removing the two wiper connections from the tone pots to kill the controls and now I like it MUCH better. :icon_confused:
I suspect the ge diodes to be responsible for the fuzziness of the distortion. Thanks Peter. I'd give it a try.
Any over thoughts?
I think the Ge diodes are D6/D7, I've removed them and jumpered D7
I also changed D3/D4 to yellow 3mm LED's
Sounds a lot better now :D
Less distortion, but nice tone and more output volume
MM.