Mark Hammers Woody Issue

[Scruffie]

Yes - the one connected to VR.  it is hard to read, but I take it to be R16.

'fraid it's still there, might have helped a bit but i'm not sure.

[Scruffie]

Yes - the one connected to VR.  it is hard to read, but I take it to be R16.

'fraid it's still there, might have helped a bit but i'm not sure.

Just tried it in and out, it did help but only by cutting a large portion of the treble out, same effect as rolling the treble knob back.

Although it may be a case that I end up having to accept I can't have all the treble in which case this'll be useful to bring back a full range of control on the knob.

Me again...

I just had a thought regarding the highpass built around ic1d. I see it has a bit of loop gain - maybe it has enough resonance around it's cutoff frequency that it's ringing when passing audio and that's interacting with the signal. Perhaps someone could run a Spice sim on it?

Perhaps it may be worth temporarily shorting the 22k feedback resistor to lower the loop gain to unity in order to test this (there are two resistors marked R15 around ic1d so I'm referring to the top one). If the ring mod distortion lessens then this might be the problem.

Does this sound feasible or am I talking out of my hat?  

Tried this, which obviously killed the treble section, but I think there was still some artifacts, harder to tell without the treble but still.

Maybe i'm just asking for too much treble out of this.

[petemoore]

  Guess I didn't hit 'post' before, when...
  I wrote a longwinded dissertation to get around saying basically this:
  Maybe i'm just asking for too much treble out of this...while relating the importance of debugging and value checks as a first, making sure it works as intended, to determine if that's right for your rig and tone needs.
   In other cases it varies because of peripherals like source/pickup and other factors change, swapping 'periheral circuits' [guitar/amp/cables,etc.] is another way to further 'debug'.
  Working 'right', and '''working as intended'' don't always follow from one player/setup to the next.
   

[cpm]

I dont know what this circuit sounds like...
but try buffering your Vr

[gritz]

Hey Scruffie, are you plugging your guitar direct into this box and running that into your amp?

I wasn't getting on very well with my compressor idea, so I breadboarded your filter and jerry-rigged a software frequency sweep and spectrum analyser (my breadboard's wired up to the PC through an audio interface so it didn't take long).

The filter isn't showing any resonance, so ignore my previous post. It's cutoff (-3dB) point is *about* 5 kHz. I forgot to turn my monitors down at first too, so there's probably dogs barking all over the neighbourhood now.  

Now here's the rub. Ignoring your "ring mod" problem for a moment guitars don't output a great deal above 5kHz. If you're looking for "brighter" in a guitar sense you might want to try bringing the cutoff frequency down some. Mebbe when you breadboard it try 22k resistors in the filter rather than 10k. Looking at the schemo again the lowpass filter cutoff is set to more than an order of magnitude lower than the highpass. this will (I guess) produce a massive mid scoop, but it's obviously been designed that way.

I don't know anything about Sallen-Key filters, but perhaps there's one of those online development applets on the interwebs. It's a 3rd order (18dB / octave) btw, which may help with the search.

I'm interested to see what other more knowledgeable folks make of this.  

[Scruffie]

Guitar Straight in and straight to amp yup.

Cheers for helping dig in to it!

Yes it's designed for the midscoop which helps produce the acoustic tone, I wouldn't say I want a 'brighter' sound but I prefer it with higher treble settings, with the bass up full too.

I'm not one of those more knowledgable folks when it comes to filters so i'll be interested in what they say too! 

When I get the chance I think this is definitley a breadboard job now.

[gritz]

*Facepalms*

Aaaaahh... that's why it's called Woody! Jeez, I'm a dunce. Yeah, the high treble freq makes sense now.

[Scruffie]

I dont know what this circuit sounds like...
but try buffering your Vr

That's not really an option with this board, i'll try it if I breadboard the whole circuit though.

[WGTP]

Am I going to be the only one stupid enuff to say something about the title of this post.  I thought he was having man problems...   

[gritz]

Am I going to be the only one stupid enuff to say something about the title of this post.  I thought he was having man problems...   

[Scruffie]

Am I going to be the only one stupid enuff to say something about the title of this post.  I thought he was having man problems...   

I was thinking it when I posted, glad someone else has a dirty mind.

I'll say with great confidence though... Mark Hammers Woody is fine... I mean, what 

[Scruffie]

Fixed! Dodgy 100pF cap in the distortion feedback was causing the majority of it, still get the noise slightly but that may well be the amp / altering the high pass to suit me. Either way it's acceptable now  back to loving this pedal!

[Mark Hammer]

Phew!  All it took was a 100mg capsule.....er....a 100pf cap. 

[gritz]

 

Glad you're getting on top of it Scruffie. The Woody, I mean. No, that sounds wrong...