madbeanpedals::forum

Projects => General Questions => Topic started by: Rockhorst on February 23, 2016, 03:12:08 PM

Title: A bit more high end from zero point SDX2?
Post by: Rockhorst on February 23, 2016, 03:12:08 PM
I've posted this question a while ago and Brian was kind enough to answer promptly. However, the topic seems to have disappeared and I don't remember the answer.

I'd like a bit more of a hifi quality to the repeats of the Zero Point SDX2 in analog mode. Possibly, this could be done by filtering out some more lows? Brian pointed me towards a certain capacitor, but which one was it? I've also tried comparing various Zero Point schematics, but though they are similar in structure, the component values vary quite a bit. Sorry for the repost, hope someone can help me out for the second time.

Also, which components should I jump to bypass the tone control completely?
Title: Re: A bit more high end from zero point SDX2?
Post by: claytushaywood on February 25, 2016, 03:33:18 PM
the tape mode's filtering and tone control (tone 1) is based off the big muff's tone stack.  I'm not sure if its exact, but turning that tone control clockwise should filter out like all of the bass.  I would imagine that would get you a lot of noise though (maybe not).

You could modify the mids of the big muff tone stack to be flat.  this would basically allow you to either have a flat eq or cut lows or cut highs.  Id probably try this.  OR you could add a mids control that works in conjunction with the tone control (another knob on the zero point- but hey thats why you built this right?!?) That would allow you to actually boost the mids.

here's some links on how to modify the big muff tone stack.
http://www.muzique.com/lab/tone3.htm

http://www.kitrae.net/music/Big_Muff_Mods_and_Tweaks_Page.html

with this second link- scroll down and look for "Tone Stack Mods" underneath it you will see a little schematic with the tone stack and 2 resistors and 2 capacitors.  the translation of these to the zero point is as follows.

R1=R30
R2=R31
C1=C33
C2=C34

So for flat mids try...
R30=33k
R31=33k
C33=5.6n
C34=5.6n

I can help you implement the mids potentiometer if youd like
Title: Re: A bit more high end from zero point SDX2?
Post by: Rockhorst on February 25, 2016, 08:20:04 PM
Yeah, I know the BMP tone stack and have experimented with it on other builds. Thing is, the tone control is already maxed :P
Title: Re: A bit more high end from zero point SDX2?
Post by: JC103 on February 26, 2016, 12:28:12 AM
Out of curiosity, how hifi does this Rebote 3 demo sound in comparison to your ZPSDX2?

https://www.youtube.com/watch?v=W0ugyl_IdWc (https://www.youtube.com/watch?v=W0ugyl_IdWc)
Title: Re: A bit more high end from zero point SDX2?
Post by: Rockhorst on February 26, 2016, 10:34:21 AM
From the video, I'd say the modded one seems to sound more like the tone I'd like to go for. It seems a bit crispier. I think the ZZSDX2 has quite a bit more filtering going on. Didn't know there was a rebote 3 actually. I'll compare schematics.