Zound Zkulptor Booster

[MJ_Sound_Cubed]

A good guitar booster should adapt to its position, and to the needs of the guitar and guitar player.

The ideal booster needs to reflect the Fletcher–Munson curves, because since the ear hears different frequencies at different levels, when the guitar signal is amplified it should remain pleasant and equivalent.

I decided to use a MOS-fet because the bias, impedance and sound can be altered and adapt any guitar pickup and playing style.

A prototype was created after investigating a bit some popular boosters.





More here https://soundcubed.com/zound-zkulptor-booster/.

[pickdropper]

Just curious, how do you accommodate the shift in frequency response at the various volume settings to match the Fletcher-Munson curves?  Is it matched to a particular SPL level?

[MJ_Sound_Cubed]

Hey man, if you check the schematic, you will notice that there is are a few RC filters and switchable capacitors. That will help to balance out  the changes in SPL/frequency.

[nzCdog]

Cool project 

[pickdropper]

Hey man, if you check the schematic, you will notice that there is are a few RC filters and switchable capacitors. That will help to balance out  the changes in SPL/frequency.

Yeah, that was my fault.  I didn't click on the link because I thought it was a soundcloud link and it was a soundcubed link.  That's what I get for reading small text on my phone.  ;-)

OK, so the Fletcher-Munson curve adjustment is basically like a loudness contour on an old hifi receiver.  Or does it operate in reverse where one cuts bass when the volume gets louder?  It's an interesting decision really, because so many guitarists listen at high enough levels where a bass increase is theoretically not necessary.  Of course, if one is headlining Madison Square Bedroom at 80dB, a bit of a boost with a sub-100hz corner frequency might help.

Years ago, I had the notion of making a headphone amp with a continuous Fletcher-Munson compensation curve tied to the sensitive of the earphone used and a specific SPL level.  That was a bit more complicated, however.

Anyway, interesting project.  I hope you are digging the results.

[MJ_Sound_Cubed]

Yeah, quite a multitask little pedal and Im enjoying the results.