tone bender mk1 help?

[jacket]

Hello
I'm new to building pedals.
Built a tonebender based off the Gary Hurst Tonebender MK1 layout here.
Everything works and sounds awesome.....but 2 problems.

Volume is very low. I have to turn the pot all the way up to get unity.
And when bypassed, there is a very quiet fuzz still happening. As if the effect
was on 2% of my clean signal.

I used a MK1 OC75 set from smallbear.

Any help would be amazing!

[inefficiency]

For the output volume problem - I know that many vintage effects are just like that. I'm sure the original Fuzz Face you had to crank just to get unity. Someone else might know better on this one, but I think that might just be the deal.

The fuzz still happening sounds like some sort of bleedthrough. Do you use the wiring method on the "offboard" page of this site?

Also, do you have any wires in the enclosure running close and parallel to each other?

[jacket]

For wiring, I used the offboard wiring from tonepad.
No LED or DC jack.

Some wires are running close inside the enclosure. Tried to make it neat.
I'll check it out. Hopefully it's an easy fix.

The volume issue isn't really a big deal. Just wish I had some headroom.

[rocket88]

i think its an offboard issue. i'm not sure what method tonepad uses, but for some reason i think i remember that you are supposed to use the millennium board to prevent issues, because it's not true bypass. just double check that, but i would suggest using the method here, works great every time.

[jacket]

this is the wiring I used:

http://fuzzcentral.ssguitar.com/faq/dpdtwiring.gif

[IvIark]

I've built this from this layout and there was plenty of volume, so I think you're looking for a poor connection somewhere.   And that method of bypass wiring doesn't ground the circuit input during bypass so you can get bleed through.   I'd recommend changing it to the method shown on the offboard page of the blog.  The switch is like this:

1---4---7
2---5---8
3---6---9

1 to 3 are used for the LED, so just follow 4 to 9 for your DPDT stomp

[jacket]

Cool.
I'll try that wiring.
Thanks!!

[Frank_NH]

Some interesting reading at FSB here...

Sola Sound - Tone Bender Mark I (1965)

"I had to change the 2.2M in my build to 1M to get unity gain with a strat, and for me the ideal value was to lower it to 100K for a "typical" amount of extra volume available on the Level control. I don't think this changed the tone too much other than reducing the gating slightly (which is a benefit) but I'll have to do an A/B with the 1M to see if there is any tonal shift happening. You can jumper that resistor too but then the level is over the top and out of hand."

"Humbuckers indeed seem to overload the input of this circuit and create a sag or "squish" sound, which can be used musically for effect on heavy strums. I've found it works best with low/vintage output pickups, or tweaking the volume knob on your guitar as someone else mentioned."

So try replacing the 2.2M resistor with a lower value.

[jacket]

Update:
changed the wiring and there is zero bleedthrough now.
also lowered 2M2 to 1M and now have headroom.

really stoked about this pedal. sounds great.

Thanks for the help!!

[jacket]

finally got around to making a demo on this build.
wanted to share it here since I got great help.
Thanks again!

http://youtu.be/GA8bWM7vUIs

[Heath]

jacket wrote

finally got around to making a demo on this build.
wanted to share it here since I got great help.
Thanks again!

http://youtu.be/GA8bWM7vUIs

Just a couple of thoughts...

1. I'm not nuts about how that pedal sounds.  I don't care for splatty, though the lead playing did definitely work better than the chording. This is all my personal opinion, though, and I am probably in the minority.  Note that I am speaking purely about the pedal sound... you're playing is bad-ass,  The way you swept through "Hang on to Yourself" made me a bit jealous.

2. You're playing vintage Bowie, man... I don't know who the hell you are, but I like you!  Great great stuff!  

3. I bet you'd LOVE a Tone Bender MkIII or Joe Gore's "Super Fiend" project (vero based, and a quick easy build).

4. I built both of the ones above with cheap Russian germaniums and they sound awesome.

5. I don't always know what the crap I'm talking about, so take the above points with a grain of salt.  Except the part about Ronson-era Bowie being awesome stuff.  That's 100% true.  Oh, and also the part about your playing.. I'm diggin it big-time.  And the part about Russian germaniums sounding awesome.. they do, seriously.  If Jimi had gotten his hands on some, we might have been hearing the USA National Anthem played through some of Cruschev's finest military electronics :p

[rocket88]

heath, is the MKIII that awesome? it's on my build list, but i've always thought the MKII sounded best to my ears. but, i think tonebenders are like fuzzfaces, you need one of each just to be happy and make sure you've got what you want, but luckly with fuzzfaces you really only have to worry about Si and Ge, but you can have so many variations due to transistor choice....

[Vince]

I've made the MkII a few times with both AC128 and Russian 308's and that sounded so sweet.. the way it sustains into feedback is something I can't get with any other fuzz, only a Tonebender. I want to get around to trying the MkIII too though...

[Heath]

It's just so subjective.  For example, when I first started building pedals I built a Triangle Big Muff and absolutely hated it.  I spent out the wazoo on those expensive transistors and everything and ended up dismantling it to recover parts.

I had a pcb from guitarpcb.com, the MUFF'N that I got as a freebie and decided to give the BMP another chance.  It sounded a bit better than my Triangle (I used mostly Green Russian values this time), but what really got me was the "Muffbender" switch mod that approximates a Tonebender (they do not state which version).  I never wanted to change that switch.

So, when my pedal building addiction finally reached boiling point for building another fuzz, the mods had just posted that three knob Tonebender MkIII and I thought it would be nice to have a simple 1590B TB with three knobs instead of the 6 knob 2 switch MUFF'N monstrosity.  I also recall Miro having some glowing reviews for it.  Also, I had a bunch of germanium transistors I was itching to use in something and nothing to do with them.  So I built it on a lark.

As soon as I plugged it in and played the first chord, I knew THIS was the fuzz I'd been looking for.  Don't get me wrong, I'm a huge fan of the Black Arts Pharoah (I realize there's some irony there) and it's like 95% everything I could want in a fuzz, but the Sola TB MkIII just nails it for me.

It's never too harsh (your germ gain choice might change that) and never splatty.  It's like good crunchy peanut butter.  Lots of crunch but never hurts your teeth.  I like a fuzz that crawls right up under your skin rather than one that slaps the shit out of you.

Here's a decent example of a MkIII (I've just moved and most of my pedals are still stashed somewhere, so this is someone else's video)


and one with more lead playing


I do want to build a MkII at some point.  It's ridiculously popular and there must be a reason :p  

[rocket88]

agreed, with some many versions why not just make them all .

i want to build the dam greasebox, as it seems like an interesting extension on the tonebender family. but we all know there's the dam-coolaid, and i really don't want to get sucked in that. lol

[jacket]

I forgot that I posted here awhile back.....THANKS for the Feedback!

So, I've swapped transistors around and dig the overall sound I'm getting.

Question: How would I make this pedal less gatey?

[Frank_NH]

I've not look at the circuit in any great detail, but a "gatey" response is probably due to some sort of misbiasing of one or more of the transistor stages.  Reading the comments about this circuit, it seems the best approach is to get a bunch of suitable PNP transistors and see which ones work best.  And I thought JFETs were a pain...

Here's some additional debugging info from the Geofex site:

Geofex - debugging bias problems

[Travis]

This circuit is usually really finnicky to get right. It's a balancing act between getting a nice fuzzy sound without going to far and getting shitty artifacts (crackly fizzy sounds) as well as getting the decay to be slightly gated but not really Nintendo bleep blop decay

Unfortunately I really don't think the smallbear MKI set will cut it. I got one (I actually asked Steve to start selling them :P ) and I was not pleased with the results. I'm afraid he selects the transistors to some specs that I don't dig at all. I've gotta say his other sets that I've tried are amazing, but the MKI was not my cup of tea

The only way to go, as most of us have found, is to buy a bunch of leaky germs and have at it. It takes some time and lots of experimentation. Leakage is key to getting a good bias. Gain is key to get a nice fuzzy sound but too much will yield nasty artifacts

I recommend buying as big a bag of AC125s as you can afford. I just got 100 for $40, which is an ok deal. These are leaky and usually you'll be testing them and you'll find some transistors that are just really too leaky to be useful for anything else but they're perfect for this circuit

[rocket88]

Agreed. The Russians I hfe stocked up on don't really cut it, as there is typically little to no leakage for the ok ones everyone tries to get, but there some that have a good amount of leakage for the tonebender, and they can be cheap, like dirt cheap if you can find them. Unfortunately, I don't have the model numbers on me now, as they're at home and burried, but will gladly let you know when I dig them out, hopefully next week. Also, the thing is with Ge transistors is that different models have different personalities, which is why we started the Ge discussion thread that's stickied here. But, long story short, if you can swing if get a bunch of different ones, sort them, and we what you like. Some of the tonal differences can be startling.

[iggy]

Heath, thanks for mentioning this version of the bender. never really hear anyone talk about it. But i did follow your links to the sound samples. and WOW, that sounds great. It's officially on my build list now. Thanks for that. I think you description is spot on. Not overboard like some of the benders. but just the right amount of grind. I love the smell of germanium in the morning. smells like Rock.