SolaSound - Tone Bender MK1.5

jalmonsalmon · Post by **jalmonsalmon** » 07 Jun 2013, 17:59

Well,
I was socketing transistors and found a pair that work great!
pair of mullard OC84's. They tested out as Q1 110 hFE .162 leak, Q2 150 hFE leak 243 - same type of test rig like RG on the Geofex website
Pedal fuzz is really thick but cleans up great with a Strat....

jalmonsalmon · Post by **jalmonsalmon** » 07 Jun 2013, 21:33

Here is a sound demo of my tonebender mk1.5 I just did... OC84s

youtube
or if youtube not working Soundcloud link:

I like the sound of this one... I will know if it is really killer when I test it out with the band later... Playing in an Apartment with a Fender Deluxe Reverb is not good... pisses off the neighbors

DonDougie · Post by **DonDougie** » 10 Jun 2013, 10:01

phibes wrote:EW's right. Even 200-300uA for leakage ain't bad on those. Those shouldn't spit nearly as much a Fuzzrite. Were you tweaking the bias on Q1 or Q2?

Electric Warrior wrote:Some of them do have a sweet kind of nastyness going on, though.

I only messed with the 8k2. With higher leakage it did sound more like the one in the video, albeit not as gated. So there is quite a bit of wiggle room to tweak it to everyone's liking

jalmonsalmon · Post by **jalmonsalmon** » 29 Jun 2013, 04:47

Chiming in and really what some people do not get... Something like a Tone Bender MK1.5 or a good Fuzz face imo sound best or lets just say... ONE OF THE best sounds you can achieve is placing said pedal in front of a roaring Marshall JMP50
59SLP or anything similar and just cranking those beasts, them slamming with with your fuzz... EPIC just ask Jimi

THAT IS ALL

(sad part is most blokes cannot do that)
I just put another set of OC84s (red dot) in my Tone Bender MK1.5 and now I am addicted to it...

Had another set I stole from my Mk2 so I had to go buy another set LOL

Masuto · Post by **Masuto** » 08 Nov 2014, 00:17

beedotman wrote:This is how I see it.

Hi Bee. I am currently building from your layout.. I will use my fave fuzz face trannies. And use a trimmer instead of 8k2.
I will report tomorrow with clips i think
Thanks for now

The Rotagilla · Post by **The Rotagilla** » 30 Nov 2014, 23:06

Quick question...

I built a 1.5 awhile back using OC75's but it seems to have low output. I switched the transistors out for another pair and the output was perfect. I tried two other pairs of OC75's and the output dropped again. I talked to a friend who has an original 1.5 as well as several clones and he says it's something about the OC75's themselves (not mine specifically, OC75's in general), is that true? Thanks.

ljn · Post by **ljn** » 30 Nov 2014, 23:16

I've been wanting to build one of these for a long time. I checked out some demos a while back, and they sound pretty good. Nice and trebly. Not muddy, like a fuzz face. I'm not knocking the fuzz face, but the tonebender mk 1.5 sounds way better.

Electric Warrior · Post by **Electric Warrior** » 20 Mar 2015, 14:55

Just scored a rehoused MK1.5.

Here's the voltages

Battery: -9.99V
Q1 C -0.31V B -0.08VE 0
Q2 C -7.64V B -0.32V E -0.24

Hardly any different from the last two stages of a MKII. I'm not surprised...

jalmonsalmon · Post by **jalmonsalmon** » 20 Mar 2015, 19:55

Electric Warrior wrote:Just scored a rehoused MK1.5.
Here's the voltages

Battery: -9.99V
Q1 C -0.31V B -0.08VE 0
Q2 C -7.64V B -0.32V E -0.24

Hardly any different from the last two stages of a MKII. I'm not surprised...

Nice!
That one has the OC75s?
I know my issue with OC75s is I cannot find any that can be used for Q1 unless I severally alter the biasing resistor for Q1, But thanks for the voltages! Will come in handy

Electric Warrior · Post by **Electric Warrior** » 20 Mar 2015, 20:03

Yeah, OC75s.
What's wrong with yours? Why can't you use them for Q1?

jalmonsalmon · Post by **jalmonsalmon** » 20 Mar 2015, 20:49

I had one on a breadboard and to get mine to bias correctly,
I had to replace the 47K resistor on top of Q1c with a potentiometer, and bias the transistor that way.
I forget what the reading was on the pot but if I remember, it was really low. I think the OC75s I have are too leaky..
They all work great for Q2 if I use say a OC84 for Q1 or AC125. I did not touch anything else, leaving 8k2 resistor and all the other stock tone bender 1.5 components.
And I refuse to buy anymore OC75s because they are getting way too pricey on the fleaBay. Plus everything I have bought were pretty leaky.

Electric Warrior · Post by **Electric Warrior** » 20 Mar 2015, 22:13

They should be pretty leaky. That's how they're specd as far as I know.

I'm not so sure about the MK1.5, but in a MKII the leakage really helps. I never even had any voltage issues.

I don't have any experience building a MK1.5 with these, though. Have you tried different hfe setups? Matched vs spread, high vs low etc.?

jalmonsalmon · Post by **jalmonsalmon** » 21 Mar 2015, 18:09

I will have some time tomorrow to have at it again with the breadboard and will post some voltages I am getting. And also the transistor hFE and leakages.

Electric Warrior · Post by **Electric Warrior** » 21 Mar 2015, 19:23

Cool. I would be surprised if you couldn't get this to work as intended with OC75s.

jalmonsalmon · Post by **jalmonsalmon** » 22 Mar 2015, 19:54

Well,
Here is what I got to work so far...
Q1 C -0.41 B -0.09 E 0
Q2 C -7.42 B .41 E .33

Not too bad and with OC75s! Very fuzzy, LOUD and sounds good too! lol

But I had to tweak 47k resistor down to 25K and 8k2 now is 5K

I will have to swap around some transistors and find a great working pair with closer to stock values of the 1.5 but I am on track and your correct...
OC75s work very well indeed. So far my breadboard sounds more or less like many clips I have heard. Fun pedal

jalmonsalmon · Post by **jalmonsalmon** » 22 Mar 2015, 19:56

Oh... all the voltages are negative.. I forgot to add the minuses on those last two
(Q2 C -7.42 B -0.41 E -0.33 )

Electric Warrior · Post by **Electric Warrior** » 22 Mar 2015, 23:06

With stock values it should be fairly trivial to get the voltages into the right ballpark. The mess begins when you try to bring them down to where some people believe they need to be.

jalmonsalmon · Post by **jalmonsalmon** » 23 Mar 2015, 04:42

Electric Warrior wrote:With stock values it should be fairly trivial to get the voltages into the right ballpark. The mess begins when you try to bring them down to where some people believe they need to be.

Yep,
I want to avoid that whole mess and stick with stock values!
Oh on another note... I made 1.5 with a silicon pnp for q1 and an OC75 for q2 that sounds awesome. I am tempted to box it up and try it out with the band heheh

Torries · Post by **Torries** » 01 Aug 2015, 07:48

I just build this one and used Electric Warriors Layout. I added a 3PDT for true Bypass and a LED. Also I used an IC to convert the Voltage to run it with negative ground.

It does work, but it's very silent und I guess it's not sounding 100% correctly. I kind of get an octavia sound when playing on higher frets. Additionally I used a Rainbow LED and I can hear the color change within the signal.

Any advice?

beedotman · Post by **beedotman** » 07 Aug 2015, 14:21

Nice example of IMPEX MK1.5

Looks like very early one.

SolaSound - Tone Bender MK1.5 [schematic]