DIY Effects

[Al Heeley]

Heres the finished tubescreamer mod pedal using the little clipping diode switch i made earlier. Another great distortion pedal for either lead guitar or bass using the phat switch, big tonal range, i just love these pedals

[JackLondon]

Nice How do you do your labels Al? They look cool.

[Al Heeley]

Cheers - I print in reverse onto inkjet transparency film, they used to use it for overhead projectors, when its dry I smear a very thin film of epoxy onto the case then glue the printed film to it ink side down. Does a good job and you can exercise your artistic tendencies with colours, textures, graphics, etc to get a pretty nice looking pedal

[Al Heeley]

Little module I was working on yesterday:

Its a small capacitor switching pcb, comnnected to a 4-way rotary switch. By replacing the stock capacitor in your circuit with the black & brown leads you can select 4 different combinations of capacitor to give (in this example) a range from 0.68uF down to 0.05uF. You can shove this into any circuit you want to mod - this will go into a tubescreamer circuit to replace the stock 0.047uF input cap, and give 4 different levels of bass boost. You could of course use the same little module to replace the tone cap in your guitar, a la gretsch or varitone in the Gibson Lucille..
My next tubescreamer build will be the most versatile so far: standard gain (1meg pot), tone, vol knobs, plus 4-way rotary switch for 4 different values input cap selection, another 4-way rotary to select one of 4 different diode clipping mods, and an on-off toggle switch to bring in a smoothing cap in series with the selected diode clipping.

[JackLondon]

Cool I'm soon going to attempt to build a fuzz factory with some mods so I'll be posting loads of questions on here.

[Toasted]

Adding the smoothing cap to the clipping diodes is a nice mod. Also works well in the DOD250.

[Al Heeley]

I'm taking a stab at a 150pF smoothing cap to start with - is that in the right area? This unit will get 50/50 usage for bass and lead guitar

[Toasted]

Al, I'm sorry I don't remember what cap value I used. I'll take a look tonight for you .

[umph]

your talking about adding a lowpass at the end of the circuit, use this to calculate the ideal cutoff point - [url="http://www.muzique.com/schem/filter.htm"]http://www.muzique.com/schem/filter.htm[/url]. resistance is the size of the level pot roughly.

[Al Heeley]

Not wanting to alter tone at this point, I was assuming the smoothing cap influences the amount of clipping to change the overdrive/distortion characteristics, not cut the high frequencies. The cap is put in series with the antiparallel clipping diodes.

[umph]

[quote name='Al Heeley' post='834345' date='May 11 2010, 04:07 PM']Not wanting to alter tone at this point, I was assuming the smoothing cap influences the amount of clipping to change the overdrive/distortion characteristics, not cut the high frequencies. The cap is put in series with the antiparallel clipping diodes.[/quote]

series? this is in a dod250 sort of arrangement right? that'll just affect the frequency of which the clipping will effect, in this case a small cap is gonna make it just effect the high highs (again you can work this out with the rc filter calculator i linked to)

[Al Heeley]

oops not series, parallel - sorry. this is a tubescreamer circuit.

[Al Heeley]

Latest evolution of my Tubescreamer overdrive.

Now has 4 different levels of bass boost plus 4 different selectable diode clipping configs, plus additional smoothing cap switch to alter the dynamics for the distortion.

[cm261]

Very impressive, sounds like countless hours of tweeking available! Lovely finish too, both inside and out.

Do you build these just for yourself, or sell them, Al?

[Al Heeley]

I make them for myself then I find friends, fellow guitarists or bassists, who want to use them or even occasionally buy one which helps fund the next build and the next evolution. Most of the guys I play music with end up having one sitting on their pedal board. I think I've come to the end of the road for tubescreamer tweakability now so I'm going to have a go at a small clone chorus, since I'm pretty unimpressed with my Boss CEB3.

[Ghost_Bass]

I'm sorry if this question has already come up but has anybody successfully modded a behringer VT911 to suit a bass? I've searched the web but only found mods for improving the pedal sound for guitar.
I have a Markbass Distorsore and love the sound of it but is way to big to fit in my board. I would like something smaller to give just a valve drive ( the key word is drive, not distorsion or fuzz, just a bit of bite in the signal) in the high freqs but maintaining my bottom end. I think a mod to make the VT911 able to act on the low freqs of bass plus a blend knob for fx/clean would be sufficient. Oh, and a new valve as well (i have a EHX 12XA7 at home). I have a few skills for soldering and have a very basic knowledge of electronics but not even close to define what kind of caps or resistances to apply here or there on the circuit. I'm willing to take the plunge and buy one to become a guinea pig for this experience.
Some help would be very appreciated.
Cheers

Edited May 16, 2010 by Ghost_Bass

[cm261]

[quote name='Al Heeley' post='838576' date='May 16 2010, 01:17 AM']I make them for myself then I find friends, fellow guitarists or bassists, who want to use them or even occasionally buy one which helps fund the next build and the next evolution. Most of the guys I play music with end up having one sitting on their pedal board. I think I've come to the end of the road for tubescreamer tweakability now so I'm going to have a go at a small clone chorus, since I'm pretty unimpressed with my Boss CEB3.[/quote]

Great work. Maybe look at putting this 'ultimate TS' pedal on the market, I'd imagine there would be a lot of interest from certain people (myself included) due to the sheer range of options. Added to that the fact that it's a very clean and professional looking build. Hypothetically, what do you think you would have to charge for one of these to make it worth your while?

[Al Heeley]

sent u a pm if you're interested in having a quick test drive, let me know

[LukeFRC]

[quote name='Ghost_Bass' post='838586' date='May 16 2010, 02:13 AM']I'm sorry if this question has already come up but has anybody successfully modded a behringer VT911 to suit a bass? I've searched the web but only found mods for improving the pedal sound for guitar.
I have a Markbass Distorsore and love the sound of it but is way to big to fit in my board. I would like something smaller to give just a valve drive ( the key word is drive, not distorsion or fuzz, just a bit of bite in the signal) in the high freqs but maintaining my bottom end. I think a mod to make the VT911 able to act on the low freqs of bass plus a blend knob for fx/clean would be sufficient. Oh, and a new valve as well (i have a EHX 12XA7 at home). I have a few skills for soldering and have a very basic knowledge of electronics but not even close to define what kind of caps or resistances to apply here or there on the circuit. I'm willing to take the plunge and buy one to become a guinea pig for this experience.
Some help would be very appreciated.
Cheers[/quote]

do you have a schematic?
I wouldn't have thought it would be too hard?

[LukeFRC]

search freestompbox.org....

schematic trace.... [url="http://i197.photobucket.com/albums/aa211/bajaman002/VT911schematic.png"]http://i197.photobucket.com/albums/aa211/b...11schematic.png[/url]


except i've got this sneaking suspicion your circuit board will be surface mounted (i guess how they keep the costs down?) so good luck!

[Al Heeley]

I'm no expert on this but the best place to start might be replacing the 47nF input cap with a 0.47uF cap to let more lowere frequencies through into the circuit. That's where i would start.
Then you have that 0.047uF cap attached to Vr on the tone pot. Try increasing that to 0.47uF as well.

[escholl]

This started out as a DIY effect, an Ampeg Scrambler clone about....2 years ago?



But I never had much use for it, because while it sounds really fantastic on my bass, I found it had to be driven quite hard to really sound good, ie I basically needed a preamp or even better another fuzz before it to really make it sing. So, it sat unused, then it sort of got added to another project...




I'm trying to think of a way to incorporate this into my bass sound now

[JackLondon]

Hi Chaps,

I've built a fuzz face for my guitarist but he says that it's not ''beefy'' enough, I use schematic from here [url="http://www.musikding.de/product_info.php/info/p1620_The-Face-Germanium---Fuzz-kit.html/XTCsid/39234f691992d87833cb450a8ffe5743"]http://www.musikding.de/product_info.php/i...3cb450a8ffe5743[/url]

So my question is what should I change to make it more beefy sounding, I assume it will be the cap C1 which is 2.2uF, should I change it something bigger like 4.7uF ?

Will this sort it out or would you say I should change some other parts as well ?

Cheers
Jack

[Al Heeley]

I don't think changing C1 will be enough, its already quite big - that's not acting as a hi-pass filter, they are normally tens of nanofarad value.
Look at C3 output cap (10n) try increasing that to 100n and see if it thickens up the sound.
I would not like to advise about changing any of the resistor values as it might upset the biasing of your trannies.

[umph]

[quote name='JackLondon' post='841710' date='May 19 2010, 09:18 AM']Hi Chaps,

I've built a fuzz face for my guitarist but he says that it's not ''beefy'' enough, I use schematic from here [url="http://www.musikding.de/product_info.php/info/p1620_The-Face-Germanium---Fuzz-kit.html/XTCsid/39234f691992d87833cb450a8ffe5743"]http://www.musikding.de/product_info.php/i...3cb450a8ffe5743[/url]

So my question is what should I change to make it more beefy sounding, I assume it will be the cap C1 which is 2.2uF, should I change it something bigger like 4.7uF ?

Will this sort it out or would you say I should change some other parts as well ?

Cheers
Jack[/quote]

personally change r4 for a 1.5k and change the fuzz pot for a 2k, also as said try increasing the output cap to anything up to 1uf and i'd personally LOWER the input cap makes the whole circuit sound less farty and more open, which makes it sound less compressed and more crunchy ie. beefy