Sparklehorn Mods

[claytushaywood]

I am loving the sparklehorn so far but am looking for others experience in a few areas.

Didnt the Timmy use the higher gain 4559 opamp?  Would it be worth ordering one to try this out on this pedal?

The main concern I have is with the delay's tone control.  I love the tone fully clockwise, but all of my sweep is in the last 95%.  It is basically three sounds- fully clockwise filtered- a nanometer backed off from fully clockwise then everything left of that sounds the same and is not my cup of tea.  Is there anything I can do to bump the sweep to get even more filtering when clockwise and have the current clockwise position be somewhere around the middle? 

I'd really like to get a bit more control and more filtering.  i'm guessing c16 is the spot... or maybe a smaller value and or  different taper  pot?

[claytushaywood]

anyone?

[TGP39]

Hi Clay. I just saw this post and I want to help but, I'm a little confused also. Let's take a look at the Sparklehorn schematic.....
     The tone control is a 25k linear pot with lug 2 (wiper) connected to ground. The part I don't understand is what is lug 1 connected to? 
Lug 3 is connected to C16, but I would think lug 1 would be connected to something?
My first impression before looking at the schematic would be to increase this tone pot to B50K or maybe use a C25K pot so your "sweet spot" would be the second half of the rotation. I'm just confused about where lug 1 goes on that pot. If anyone could shed some light on this that would be great.
     As far as using different op amps in this circuit, only your ears could answer that question. That's why we socket them right?

I hope this helps a bit as I am very interested in this awesome circuit as well. Good luck.

Steve

[midwayfair]

Hm, I thought I replied to this.

You can try the 4559; it won't change much but might sound very slightly different.

For the tone pot, the filter increases treble as the pot decreases resistance to ground (it's lugs 2 and 3, so it's a variable resistor whose resistance gets smaller as you turn it up). If you're finding everything too heavily filtered except when the pot is all the way up, use a smaller value pot or a reverse audio taper (tough to find in 25K) to get more range on the lower end, or decrease C16 to a lower value to raise the filter frequency. You can also remove C15 or decrease its value. You could fiddle with R14 and R13, but that can affect other things.

You can also decrease C17, which is a separate filter later in the delay path.

I have to say I'm greatly surprised you're finding the highest tone settings the only useful settings, though; that ought to be quite noisy.

[TGP39]

Hm, I thought I replied to this.

You can try the 4559; it won't change much but might sound very slightly different.

For the tone pot, the filter increases treble as the pot decreases resistance to ground (it's lugs 2 and 3, so it's a variable resistor whose resistance gets smaller as you turn it up). If you're finding everything too heavily filtered except when the pot is all the way up, use a smaller value pot or a reverse audio taper (tough to find in 25K) to get more range on the lower end, or decrease C16 to a lower value to raise the filter frequency.

Thanks Jon. I now understand how this works. Greatly appreciated.

Steve.

[claytushaywood]

Hm, I thought I replied to this.

You can try the 4559; it won't change much but might sound very slightly different.

For the tone pot, the filter increases treble as the pot decreases resistance to ground (it's lugs 2 and 3, so it's a variable resistor whose resistance gets smaller as you turn it up). If you're finding everything too heavily filtered except when the pot is all the way up, use a smaller value pot or a reverse audio taper (tough to find in 25K) to get more range on the lower end, or decrease C16 to a lower value to raise the filter frequency. You can also remove C15 or decrease its value. You could fiddle with R14 and R13, but that can affect other things.

You can also decrease C17, which is a separate filter later in the delay path.

I have to say I'm greatly surprised you're finding the highest tone settings the only useful settings, though; that ought to be quite noisy.

actually the tone gets darker as you turn the knob clockwise.  pretty sure I didnt wire a board mounted pot backwards or anything.  and I'm finding all my useable range in the darkest positions.  Increasing c14 to 100n (i believe) helped get it darker, but all the action is still bunched up at the clockwise end.

Maybe increase the pot to 50kC?

[madbean]

If you find you like most of the darker end of the tone control, then I would actually increase C15 instead. Try these values: 10n, 15n or 22n. Leave C16 as 68n or 100n is okay too.

I don't know if you can those plastic shaft pots in C tapers, but that might smooth out the second half of the control.

[claytushaywood]

If you find you like most of the darker end of the tone control, then I would actually increase C15 instead. Try these values: 10n, 15n or 22n. Leave C16 as 68n or 100n is okay too.

I don't know if you can those plastic shaft pots in C tapers, but that might smooth out the second half of the control.

I will try tonight!  Trying to probe the moodring right now

Thanks!