JHS - Treble Booster ( Hornby-Skewes )

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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby Electric Warrior » 08 Mar 2009, 17:46

I'm not so sure about that. the vero board shatterbox had an 80uF electrolytic for the booster side and a 125uF for the zonk side for instance. One would expect both electrolytics to be 125uF with that part being available and so many (early?) HS treble boosters using it.
on the other hand we observed that the output cap's value was very consistent. Maybe they just tweaked certain values once in a while or only changed specs after using up remaining parts..

in any case the photos help us to see what parts they definitely used at certain points (and thus what parts they thought would do the job) and how the circuit evolved over time.
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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby Electric Warrior » 09 Mar 2009, 08:57

biffa wrote:Hmmm,
The point made,it sets a standard for certain models,is ok to a point but as builders DID sub components,folk scrutinising caps from photos WILL lead to mistakes
Just as AG pointed out,the tranny for the JHS TB is a 2n4201(some number like it),and was falsely identified as a jfet
And the fuzzface et al.used different trannys at different times,sometimes combos
Also the tonebender 'inbetweens'
We end up with a dozen 'standard' setups?
Much better to say,"use an npn si of 400 hfe(2n5089 to start)",or,"an input cap(ceramic good) from around 100nf-300nf eq'ed to taste",instead of a xxsgg4442(nepal) tranny,and a 5.45pf xeon+ cap(i think,the photo was from a weird angle?)
I'm not being facescious,these issues come up regularly,and divert from the main goal of tone
As i said,start with what you have,then explore...
(and we don't have a definitive BM 'triangle' model,others have different components in the 'triangle' setup)
(and whats wrong with 'close to'? Why do we have to change collector resistors on ffaces? To allow for different trannys to be used,the values really are 'close enough')


the problem with the hornby skewes schematic was that it was a work in progress, but some people treated it like the real thing. information was put together bit by bit, picture for picture. there just wasn't much to see in the first pictures that were available. it's amazing how fast rumours can become "facts".
If some parts are pure speculation they should be marked as such. with the pictures in this thread we don't have much to speculate anymore. we now have a definitive starting point (plus some variations of it) for people who aren't only looking for tone, but for "THAT" particular tone.

most tone bender schematics I have seen have issues by the way. Pictures helped me see them and helped me confirm what others said about that circuit.
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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby PurplePeopleEater » 09 Mar 2009, 13:45

biffa wrote:Hmmm,
The point made,it sets a standard for certain models,is ok to a point but as builders DID sub components,folk scrutinising caps from photos WILL lead to mistakes
Just as AG pointed out,the tranny for the JHS TB is a 2n4201(some number like it),and was falsely identified as a jfet
And the fuzzface et al.used different trannys at different times,sometimes combos
Also the tonebender 'inbetweens'
We end up with a dozen 'standard' setups?
Much better to say,"use an npn si of 400 hfe(2n5089 to start)",or,"an input cap(ceramic good) from around 100nf-300nf eq'ed to taste",instead of a xxsgg4442(nepal) tranny,and a 5.45pf xeon+ cap(i think,the photo was from a weird angle?)
I'm not being facescious,these issues come up regularly,and divert from the main goal of tone
As i said,start with what you have,then explore...
(and we don't have a definitive BM 'triangle' model,others have different components in the 'triangle' setup)
(and whats wrong with 'close to'? Why do we have to change collector resistors on ffaces? To allow for different trannys to be used,the values really are 'close enough')


The fact that AG took the time to point out that the transistor in the HS is not a jfet, but instead a 2N4061, should be a hint that we're not looking for "close enough", but "correct". Otherwise he would have said "it's not a jfet, just stick in any old PNP transistor".

The more accurate we can be, the better. As more and more people photograph their units and put them on the web
( :shock: ) , we will have more accurate information as to what the standard versions of any vintage effect are.

There's nothing wrong with your method, and it works for some people, but others want things to be "correct". For instance, I think you said earlier "start with a Rangemaster and go from there". Well, the HS is not a Rangemaster and does not sound like one, at least ones that are built from the current schematics. So if someone wants a HS, why would they start with a RM ? That's like telling someone who wants a Big Muff to "start with a Fuzz Face and tweak from there". You might well come up with something great, but it won't be a Big Muff. You want a Corvette ? Start with a Fiero and tweak from there. You used a kit car (Ferrari IIRC) earlier in the thread as an example - all you are doing by suggesting "close enough" is telling people to buy a Fiero and put a fake Ferrari body on it and convince yourself it's a Ferrari.

Accuracy is important. Not "settling" is important. If you think "close enough" is just fine, well, that's great - for you. But it makes no sense for you to sit here and preach to those who don't wish to "settle". Those who want to get as accurate a schematic as possible.

As for the "why do we change collector resistors on a Fuzz Face", well that has zero to do with the conversation. That has to do with "optimizing" a circuit from a known, accurate schematic. We KNOW what the collector resistor was in production units. We also KNOW we can sometimes improve the sound by tweaking it. Thats very different than "just taking a close schematic and tweaking it". That's more like adding Pirelli tires to your sports car because you know it will improve performance - but you're still starting with the stock sports car.

As for a definitive triangle schematic, we do have that. We have the "standard" version, which is the most common. It was made by scrutinizing photos, having units "in hand" to trace, etc. It is common knowledge that there were occasional value changes, but if you build to the existing triangle schematic, you will be indeed building a triangle Muff.
Last edited by PurplePeopleEater on 09 Mar 2009, 13:53, edited 1 time in total.
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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby PurplePeopleEater » 09 Mar 2009, 13:50

biffa wrote:RE;The muffs-'triangles' and such
It's a good debate so far,eh?
(click on pics to enlarge)
Check 'testing' for more on electro-harmonix


Interesting that you posted that article. What if we had gone with your 'close enough" theory ? We wouldn't know that differences between a triangle, lamb's head, violet, etc Muff, because we'd all just be settling for "close enough". In fact by following your theory, we wouldn't have the op amp version schematic either, because nobody would have bothered to crack it open and trace it - we would have already had a schematic for a "generic 4 transistor version" that was "close enough".

Accuracy is important.
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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby PurplePeopleEater » 09 Mar 2009, 13:57

biffa wrote:Hmmm,

....Much better to say,"use an npn si of 400 hfe(2n5089 to start).....


Too bad that wont work unless you also flip the polarity of the electrolytic and the power supply. The HS has a 2N4061 in it, which is a PNP, so the circuit is positive ground. The 2N5089 you suggested is a NPN.

Another case of "close enough" leading to more frustration. If a beginner tried to build a HS and used your suggestion of a 2N5089 it wouldn't work, and would lead to frustration.

Again, being as accurate as possible is important.
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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby Electric Warrior » 09 Mar 2009, 15:03

PurplePeopleEater wrote:
biffa wrote:Hmmm,

....Much better to say,"use an npn si of 400 hfe(2n5089 to start).....


Too bad that wont work unless you also flip the polarity of the electrolytic and the power supply. The HS has a 2N4061 in it, which is a PNP, so the circuit is positive ground. The 2N5089 you suggested is a NPN.

Another case of "close enough" leading to more frustration. If a beginner tried to build a HS and used your suggestion of a 2N5089 it wouldn't work, and would lead to frustration.

Again, being as accurate as possible is important.


he just wanted to give examples and used random numbers.
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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby PurplePeopleEater » 09 Mar 2009, 15:38

Electric Warrior wrote:
PurplePeopleEater wrote:
biffa wrote:Hmmm,

....Much better to say,"use an npn si of 400 hfe(2n5089 to start).....


Too bad that wont work unless you also flip the polarity of the electrolytic and the power supply. The HS has a 2N4061 in it, which is a PNP, so the circuit is positive ground. The 2N5089 you suggested is a NPN.

Another case of "close enough" leading to more frustration. If a beginner tried to build a HS and used your suggestion of a 2N5089 it wouldn't work, and would lead to frustration.

Again, being as accurate as possible is important.


he just wanted to give examples and used random numbers.


While both you and I understand that, a beginner may not. It's a good example of why it is good that people try to be as accurate as possible when giving info.
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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby Electric Warrior » 10 Mar 2009, 01:44

can anybody spot a mistake?
it's based on the layout of the booster half of a shatterbox. I could leave out the two empty strips, but with them it's easier to read.

HS Treble Booster Original.png
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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby Electric Warrior » 10 Mar 2009, 08:54

biffa wrote:Very interesting,and you're probably right,but with the JHS t.boost people saying it was ajfet caused me no end of problems
I put in a fet,and it just wasn't right,so I put in different trannys and settled on npn si darlington I think
The point is,for ages I thought I was getting more stupid than I normally am,because everyone(well,not everyone)said it was a fet


that's when you should have started to do some more research :)

biffa wrote: Yes,a designer saying this was made with a 'x',is cool,but the cult of 'vintage components' imho is leading us down a dark road(not black)
I have some really wonderful mullard trannys,a low leak oc44 140hfe yellow jacket,oc76,oc72,oc71,etc...,but in a rangemaster the oc44 ISN'T the best tranny for it
I can only guess it was the one they had and was value,so the cult of 'correct..' states it must be a yellow jacket,but there are many better subs
So, yes you're right when you say we need a fixed value to start,but being fixed in stone isn't helpful,IMHO
But good point made though.....
(but when you say "why did I then post...",I have to say I'm not an EE,I'm in the debate to learn.I was an army engineer for most of my adult life till recent(i'm 40) and my field of expertise is mechanical engineering)
My JHS t.boost is npn?


140hfe? wow. that's much. my black glass OC44s only have about half of that gain - and they work great in a rangemaster. I like their character. Most of the rangemasters that come up on ebay have an OC71. Nice as well, sounds more "glassy" so to speak, but I prefer the OC44.
vintage transistors can make pedal building easier. My tone bender sounds great with OC75 transistors. Noisy, yes, but the character. The supposedly "better" quality japanese transistors I have just didn't do the job too well. Now that I know what I'm shooting for I could search for appropriate substitutes.
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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby PurplePeopleEater » 10 Mar 2009, 15:47

Pretty much all that is true, and I'm glad you took my intent the right way. I certainly wasn't meaning to attack you or anything. I just wanted to let people know that getting things right is important, so we have a solid foundation to start experimenting with. That's the great thing about this hobby; we can easily tailor or effects to our particular liking. :D
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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby Electric Warrior » 11 Mar 2009, 02:48

biffa wrote:I'm not saying that a rangemaster shouldn't have an oc44,but that there are other vintage trannys that suit it better,like a mullard oc82d with an hfe of around 250,or an oc72,etc..
Re the research aspect,that's what got me into trouble!
Everybody was saying something different
Like it's a fet,it isn't,no caps ,wrong caps,etc...
I needed a starting point of course,but I did better after that measuring tranny values,then switching them in & out of a terminal
The yellow jacket was a find,i had 2 and some other colours like blue jacket,orange jacket(oc45etc...)
I swapped a yellow jacket(a leaky one) with digitaldude(?) for his book on vintage pedals(plus a few not so precious ones)
If you need a few good vintage mullards,pm me and I'll send a few over(i sent a few to soulsonic) for gratis(anything specific ask)
I guess it comes down to taste though
I like a gainy RM,some don't
Yes,proper values,but it can get in the way for beginners
I'm not talking about the experts.they don't need help,they have degrees!
I just think too much emphasis is put on 'has to be this way..',and personally I think doing 'exact' clones is holding tone back
Yes,if you want an exact ferrari,do it,but who's to say the kit isn't better?
If enough effort is put into the kit and understanding how a ferrari works it can be better!
Good stuff though,well thought out
(I'm reading that a choke is good on the input.I did that already because I wanted to tame it a little,so I put that well known pickup sim on-a choke,pot and caps))_


when did you build your HS booster? the sources have been very confusing up until 2006. the thread on diystompboxes.com has cleared up a lot of things.
did your reasearch get you into trouble or did it just show up the issues and speculations about that circuit? you probably had a better starting point than most.
or you had all the information you needed but came to the wrong conclusions. that would have been bad luck :)

sure, doing "exact" clones may hold tone back, but there's a certain nostalgia many people feel towards the pedals that made the sounds they grew up with. some people want exactly that sound. others want pedals with circuits made to "exact" specifications, but with certain improvements (true bypass, led, external bias pot..). then there's people who don't care for "exact" specifications and go for a different sound when tweaking their pedals. everything has it's place. an "exact" schematic is helpful in either case. If we don't try to make an exact schematic we might as well leave the part values away.

I have no doubt that the kit could be better. I still might prefer the vintage model over a hod rod or the improved and better modern version. "modern cars - they all look like electric shavers" 8)

that's a very kind offer. thank you :) I'm in no particular need for vintage germanium at the moment, but I'll get back to your offer. I might have some cool stuff for trade..
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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby Electric Warrior » 11 Mar 2009, 08:48

most likely. and somebody must have mixed up two digits.
don't believe any rumour about the transistor if there is no good photo proving it. we have excellent photos of 2n4061s in treble boosters and shatterboxes.
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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby Electric Warrior » 12 Mar 2009, 09:57

jfet? why should I? :shock:
I have not built the circuit yet, but I will use a Texas Instruments 2n4061 pnp silicon transistor of course :)

datasheet: http://www.datasheetarchive.com/pdf-dat ... 101-08.pdf
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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby Electric Warrior » 12 Mar 2009, 10:03

small bear doesn't have them. send me a private message with your postal adress.
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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby PurplePeopleEater » 12 Mar 2009, 13:57

biffa wrote:So getting one from smallbear is probably the best suggestion?
(are you 100% on the pnp aspect?)
The electrolitic caps are negative ground,usually using npn
The thing is,I tried a lot of pnp si's with no success,a 2n3153 being the final choice
Just interested in how you're going about it




This is exactly why, again, we need accuracy. There is a reason you believe it to be negative ground; the old, incorrect schematic that showed a (wrong) jfet was shown as negative ground, which would make sense that a PNP wouldn't work if you dropped it right in to the circuit. However, that schematic has been proven wrong, and the photos clearly show a 2N4061 (PNP), further cementing that point.


If you look at the latest schematic, you'll see that the electrolytic is wired for positive ground, not negative.The "+" points to ground. That makes sense because the 2N4061 is PNP.


Also, you say you used a "2N3153" in your build. Are you sure about that ? A 2N3153 is a chopper switch. A "2N5133", however, is a NPN transistor that used to be very common, and that Small Bear does indeed carry (and would work if used with the old, incorrect schematic).
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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby royaltoots » 12 Mar 2009, 15:22

...just to confirm - I built this with a the vintagerob schematic and a Texas Ints 2N4061 (hfe about 100) - it works, but to be honest it's nothing special. I'll also be trying the shatterbox (from electric warrior's layout on the DAM forum :applause: )

edit - I see the datasheet goves the hfe as 90 - 330, I tested most of mine and they were all were between 90 and 115 - i got 2 (cheap) batches from 2 different UK different suppliers, as I mislaid the first ones then found them again.
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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby Electric Warrior » 12 Mar 2009, 15:56

PurplePeopleEater wrote:If you look at the latest schematic, you'll see that the electrolytic is wired for positive ground, not negative.


that's not bassplayer's latest schematic.it's this one.

royaltoots wrote:.just to confirm - I built this with a the vintagerob schematic and a Texas Ints 2N4061 (hfe about 100) - it works, but to be honest it's nothing special. I'll also be trying the shatterbox (from electric warrior's layout on the DAM forum :applause: )

edit - I see the datasheet goves the hfe as 90 - 330, I tested most of mine and they were all were between 90 and 115 - i got 2 (cheap) batches from 2 different UK different suppliers, as I mislaid the first ones then found them again.


similar experience here. the ones I got from dialelec (print says 2n4061 TI )have a wide range of different hfes, the ones I got at a local electronics shop (2n4061 TI127F) all have an hfe 100 - give or take a few.
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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby Electric Warrior » 12 Mar 2009, 16:41

just measured all of the ones I got from dialelec. they have bent legs and it's hard to push them into the meter. most are around 175, several around 100 and few over 200.

regarding biffa's neg./pos. ground question: just look at how the battery clip is wired: the black (neg) wire is connected to the circuit board and the red one to the switch. it's connected to the ground when switched on. pictures can be really helpful 8)
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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby PurplePeopleEater » 12 Mar 2009, 18:52

Electric Warrior wrote:
PurplePeopleEater wrote:If you look at the latest schematic, you'll see that the electrolytic is wired for positive ground, not negative.


that's not bassplayer's latest schematic.it's this one.



Actually, that's his schematic for the HS Bass Booster, not the Treble Booster. The two 10k's are different and it has a 100n cap. They bleed high end to ground. Very different sound from the Treble Booster. He also drew up a "possible" schematic for the germanium one pictured in that thread.

However, this schematic is slightly later than the one I linked two posts ago, and has the I/O caps labeled in accordance with the Highfield unit and what is believed to be correct for the HS. Still positive ground, PNP with a 2N4061, which was the point of the earlier post.
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Re: JHS - Treble Booster ( Hornby-Skewes )

Postby Electric Warrior » 12 Mar 2009, 19:32

whoops, I'm sorry! I clicked too fast.. but you found the right one. that was the one I wanted to link to.
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