MXR Sub Octave Bass Fuzz Output Question

[Dan_reeves]

I just picked up one of these used due to some demos I heard and the generally positive reviews they get.

The one I received is super loud - I had to turn down my amp quite a bit to compensate from what I run it clean. I thought maybe there was a gain trim pot or something but didn’t see anything inside. There was a switch in there labeled “SM4” which didn’t really seem to do anything. Is this pretty typical for these? I mean I can turn my amp (or bass) down when using it, just wasn’t sure if this was typical behavior or if I got a “special” one. Thanks!

 

[Michael Vee]

The SM4 switch question would be a good one to pose to Dunlop support. There's nothing about it in the M287 manual, and nothing I could find online. No one has talked about this so far on TB, as far as I can tell.

 

[Dan_reeves]

I did email them, good call on that. We’ll see what they say.

 

[Steevo00]

Old thread, but in case this helps anyone…
The switch is what Dunlop refers to as SW-1 (but it looks more like a 4 to me as well.) It adjusts the frequency for the midrange control. Right is something like 430 Hz and to the left is something like 830Hz.
As far as being loud, at least one YT reviewer commented on how much gain, like just volume gain, it has on tap.
I have one and I agree. I need to set everything around 10 o’clock or below to get anywhere close to unity gain.
Also, I found the octave function really tracks poorly. So disappointing I almost returned it. To be more accurate, it seems to track pretty well on short fast notes, but the octave effect does not sustain well. Low notes sub octave drops out after like less than one second.