Would a high-pass filter help?

[paul.creedy]

I'm continuing to tinker with my stuttery Happy Little Accident (HLA) pedal and its doubled-up cousin (HLA2 )

I like what I've achieved so far but would like to tidy things up a little, in that 1) it's a little noisy (the HLA2 doubly so) and 2) playing higher notes there is a low frequency "tick" accompanying the notes, again more noticeable with the HLA2.

I also made myself a cut-down version of the HLA (which I called a Teeny Tiny Fuzz, names are not my strong point) which, when doubled up (I'm always curious what two of something sounds like ) with different transistors in each half, became the Big Brother fuzz. This I like particularly because it's quite sensitive to input level and because of that it has what amounts to a built-in noise gate.

With the Big Brother running into the HLA I can adjust the speed of the stutter with the BB vol control, so I'm thinking of making myself a new pedal with both circuits inside it (probably on one vero as neither of them are very big) and I wondered if a high pass filter might help lose that low frequency accompaniment ?

If that's plausible then my next question is where would I put it; before, after or somewhere in between? I'm guessing before the HLA part makes the most sense?

Could I make up a little high-pass filter to stick between the two pedals (either powered or not) to test the theory or would it be best to breadboard the whole thing ?

I can supply circuit diagrams if requested, and I'm happy to be told that there are more elegant ways of doing what I've done so far, but I'm having fun and learning (slowly) as I go

[GibsonGM]

Hi Paul,  I think I'm not alone when I say I think posting the diagrams would be very useful!  Hard to say much without them! 

[paul.creedy]

Fair enough

What I have right now . . .

This is the layout of the Big Brother:



and this is the circuit for the HLA:



The Big Brother is the same circuit as the HLA but with the MPSA18 loop chopped out (including the 3M3 resistor and 100nF cap) with a second identical circuit (apart from there being a BC108 and 2N2907 in the first part and an MPSA13 and 2N2907 in the second.

So what I'd like to do is create a new circuit which has the BB fuzz at the start followed by the HLA circuit. I'm planning to lose the pot at the beginning of the BB circuit and maybe the one at the beginning of the HLA too (neither do a great deal).

[MaxPower]

Maybe an audio probe (or am I thinking of something else?) to try and find it's origins?

[paul.creedy]

While I think of it - if the pot at the beginning of either circuit sounds better at the half way point than it does at either end (B100K with 100nF at one end and 10nf at the other) would replacing it with one resistor and one capacitor work ?

If so, which resistor and which cap ?

Or would it make more sense to split the input two ways with a 50k resistor into 100nF one way and 50k resistor into 10nF the other ? (to replicate what's happening with the pot in the middle position).

This all sounds a little ridiculous I know, but I like the circuit as things are and right now I'd like to remove the pot without changing things too much if possible, and as I've said before, my knowledge is limited

[MaxPower]

50k resistor in series with the 100n cap. Or both caps in parallel with each other and in series with the resistor.

At least that's my guess.

Wait a minute, if you have 50k on each side of the pot, wouldn't that be 25k?

[diffeq]

This all sounds a little ridiculous I know, but I like the circuit as things are and right now I'd like to remove the pot without changing things too much if possible, and as I've said before, my knowledge is limited

On each pot, measure the resistance from center pin to both ends, and replace it with corresponding fixed resistor values. In a B100K, it will be about 50K. In A100K you will have to measure - it is not linear.

[duck_arse]

the B100k at the HLA input should have the wiper connected to one end, so it works as a variable resistor in series with the 100nF cap.