Author Topic: Some Sunking questions  (Read 1313 times)

Liam

  • Diode Destroyer
  • *
  • Posts: 25
    • View Profile
Some Sunking questions
« on: February 22, 2011, 01:56:53 PM »
Just finished my first Sunking build.  I'll start by saying what a great pedal this is, everything worked straight off, nice straight forward build, and it sounds fantastic.  Very mellow and warm, excellent clean booster with loads of headroom and gain, and a really smooth yet clear sounding overdrive.  I think I'm using 1n34a diodes, but it's been that long they've been in the parts bin I honestly can't remember.  Late 90s small signal Ge, I picked a pair that held off about 2.7 volts as they are all over the place.  The quality of the distorted sound is lovely, so not messing with that bit yet anyway.  Got loads of Ge diodes to try when the time comes.

I've got a couple of things I'd like to try to improve on the effect.  I'll start with the subs I used for parts I didn't have or couldn't readily find:

C5 - 0.47 uF, C7 - 0.1 uF, C13 - 33 nF, C15 - 3n3.  And foolishly enough I've got a 13 volt zener in D3 that needs changing for a lower value before I run it on a power supply.  It was what I had.

Things I'd like to improve if possible: 

The gain control gets very sensitive just at the top of its travel.  I could almost consider running it back to front, as the bit I want to use is probably between 80 and 100% of full travel.  Is this a common problem?  I'm even wondering if a linear dual pot might suit better.  The Citec pots I'm using aren't great, but it somehow doesn't seem quite right.

Tone control needs to be at 75% to give a "neutral" tone.  Which I can live with.  I'm guessing this is just how they are, or is it my C15 sub?

Finally, the buffer's OK, but a little bit on the thin side.  Do most people go true bypass with these?

Being picky, I'll be using it as it is, but if it can be better..

Thanks in advance

Liam

oldhousescott

  • Electron Doctor
  • *****
  • Posts: 568
  • Scott in SC
    • View Profile
Re: Some Sunking questions
« Reply #1 on: February 22, 2011, 02:32:12 PM »
All of the pots are spec'd as linear, so if you've got audio/log tapers, that would explain both the gain and tone response you're experiencing. The volume pot could stay audio taper if that's what's in there currently.

I wouldn't expect your sub choices to have a huge impact, although they are all in tone shaping positions, so it won't sound exactly like the original circuit. If, as you say, it sounds good, just go with it.

jkokura

  • Global Moderator
  • Electron Doctor
  • *****
  • Posts: 7535
  • Jacob - SK, Canada
    • View Profile
    • JMK PCBs
Re: Some Sunking questions
« Reply #2 on: February 22, 2011, 02:38:08 PM »
The only other question I detected in there was about the bypass. I haven't seen that lots of people go with True bypass, but I have seen some who do. I personally like the buffer, and I appreciate having it in there usually.

Jacob
JMK Pedals - Custom Pedal Creations
JMK PCBs *New Website*
pedal company - youtube - facebook - Used Pedals

madbean

  • Administrator
  • Electron Doctor
  • *****
  • Posts: 9482
  • Brian
    • View Profile
    • madbeanpedals
Re: Some Sunking questions
« Reply #3 on: February 22, 2011, 02:50:07 PM »
I'm surprised that you notice much difference with the buffer. There's not much in the way of tone shaping....but there is a little, I guess. If it sounds thin, you could increase the input cap. Output cap 4u7, I think, so that's not affecting the frequency range.

And yea, you need linear dual 100k for the gain pot!

You can always increase that 3n3 to 4n7 to darken it down a hair.
I own madbeanpedals (duh). I am part owner of Function F(X).

Liam

  • Diode Destroyer
  • *
  • Posts: 25
    • View Profile
Re: Some Sunking questions
« Reply #4 on: February 22, 2011, 03:20:37 PM »
Thanks all.  I feel a bit silly now...  All my pots are marked up Lin-A and Log-B, which always used to be European convention.  Completely forgot it's Audio-A and Linear-B in other conventions.

I've really enjoyed the project - there will be more!

Liam

Liam

  • Diode Destroyer
  • *
  • Posts: 25
    • View Profile
Re: Some Sunking questions
« Reply #5 on: February 25, 2011, 08:14:01 AM »
Thanks all.  Seems quite well sorted now.  Took out all of the subs (been shopping), changed the pots for linear apart from volume.  I've left the input cap as the buffer is only noticeable into one of my amps (Fender SFPR).  I think for the first time everI'm going to gig a home-made effects pedal tonight.  Thanks!

Liam