sushi box grand slampegg

[havnjero]

looking for some clarification to mod a new pedal, grand slampegg, made by sushi box, and figured I'd use this forum instead of talkbass for the details.

it sounds real nice, and its nearly what I need in order to have a single pedal for double bass performance, so that I don't have to bring a pedal board or drive to a gig.

I'm good with an iron, but not sure exactly what components to change. here are my ideas:

1.
it isn't running a 5691 -- could be because it doesn't support the heater current needed.
6SL7 needs 0.3a and a 5691 needs 0.6a
should I change the 78M06 to a 1amp 6V voltage regulator for getting more power to the heater?

2.
changing the high pass filter from 6db/oct@90hz to a brick wall at 53hz.
space available is at red marking, courtesy of @Tassieviking. thanks!
looks like theres not a lot of space available, but what components do I need to have in there?
I know this is complicated.

3.
input impedance.
I though that 5.6MΩ would work but I need at least 10MΩ. 15.6MΩ may be ok, so I'll try adding a 10M to see how that works. it'll be switchable in the end.

@vigilante398

 

[benny_profane]

@vigilante398

 

[jwin615]

A multipole filter isn't going to be a couple of components. You need an active circuit and even that won't be a "brick wall" in the analog domain without a LOT of components. The phase shift you start introducing forces you to get into higher parts counts if you want more than 12db/octave.
The smallest TH multipole I know of is this guy
Not sure if you can hack that into your pedal easily though.
You can alter the values to change the corner frequency as desired.

 

[vigilante398]

1) not sure if you'll be able to find a higher output 6V regulator in the same package, but if you use an L7806 (1.5A output) you can mount it to the wall of the enclosure (you'll have to find an empty spot of course) and jump wires down to the pads from the 78M06.

2) as mentioned above, a steeper sloped HPF is only doable in active filter land, which means it will be a lot more complicated than just swapping a component or two. Again it may be possible to jump out a separate circuit board with some wires, but again you'll run into real estate problems as Grand Slampegg is pretty packed.

3) if you want to add the resistances you'll have to add them in series, not parallel, which means the 5M6 resistor is going to have to get removed either way.

 

[matmonster58]

I upped the hpf cap on my nobelium build for upright and its now set at around 50hz. It's pretty perfect for my upright to leave on all the time. I don't think think a steeper filter slope is al that necessary tbh. Steep analog filters do weird stuff to the phase response and create a resonance in more extreme cases.

I have a vampire slayer with 5.5meg or 11meg impedance. I was shocked to find the 5.5meg sounds way more natural with my k&k pickup. The tribal knowledge on talkbass had me thinking higher was always better. 10meg sounds fine in my nobelium, but i haven't tried different values. My MXR m81 has a 3.3meg impedance and I've never felt it was lacking. It's a different circuit and you probably have a different pickup but a higher input impedance isn't always better from my experience. I just got a new bass with a realist pickup, i haven't had a chance to try it with my different pedals yet