Boss HM-2 more volume

[LorenZo-m]

Hi,

I would like to modify my Boss HM-2 to get more output volume.
Here (LINK) seems that I have to add a diode in serie with D9 and another one in serie with D8.
But I read that I can replace the last 3.3k resistor (it should be marked as R51 or R52 on the board...) with a higher value (with 20k or but 10k that should give quite a lot more volume too).

Has anyone tried these mods? What is the best?

Thank you in advance for your kindly replies.

[antonis]

Wellcome...

<What is the best?>

I think there isn't such an answer..

When we deal with "Volume" we have to compare values (like with all other parameters..)

Now, if you add extra diodes you get more headroom for unclipped signal (more Volume but less Distortion..)
Adding these extra diodes results in doubling unclipped level which adds about 6db of extra Gain..
(in term of Volume before / Volume after..)

Changing 3k3 resistor also adds Gain in a level which depends on the new value (A=1+Rf/Rg where Rf is the 3k3 resistor) but it also results in more Distortion (how much depends on the level of remaining headroom before hitting the supply rails..)

Maybe you should try both mods and perhaps combine them..

P.S.
I'm sure that I've confused you but my English skills are tragic...

[LorenZo-m]

WoW! Thank you very much! It is very interesting!

...and don't worry... your English is better then mine!