To make this a little more versatile I'd be very tempted to lose the input and output caps (and shave off a column) and add a 4P3T rotary switch to swap input and output caps to offer a greater range of frequencies.
Maybe having:
Input caps
C1 - 5n
C2 - 22n
C3 - 47n
Output caps
C4 - 10n
C5 - 47n
C6 - 100n
or whatever suits your taste and equipment.
Oh and the collector/emitter swap cheat version for Travis, not sure how well this will work though!:o)
Cool layout and great suggestions for the cap switch.
ReplyDeletePersonally I would prefer to see one without a charge pump, set up similarly to the Fuzz Factory using PNP in a negative ground circuit.
I might be biased against charge pumps though, because they're kindof expensive and noisy in my [limited] experience with them
Travis, They're not that expensive if you get them from overseas etc
Deletehttp://www.ebay.co.uk/itm/20pcs-ICL7660S-DIP8-Voltage-Converter-/390341332047?pt=LH_DefaultDomain_0&hash=item5ae2280c4f
See above, I still think I'd prefer the charge pump though!
Delete18p each here :o)
I'm curious, why do you prefer a charge pump? I've read that the "cheat" can result in oscillation sometimes, but I haven't experienced that before
DeleteOne reason is that although I've heard people complain about noise with a charge pump, I haven't heard anyone complain when the IC is just providing a negative voltage rather than voltage doubling. Maybe that's just my own perception but I can't remember seeing anyone post about noise when they were just using the IC to get -9V. Secondly is because the transistor isn't symmetrical and so it won't behave when reversed necessarily in the same way it would when used in its intended orientation. Gain will possibly be lower and it will clip differently.
DeleteI'm not against it because the anomolies of it may actually be pleasing to the ear, and as the only real measure is how these things sound, the theory behind it all takes a back seat. But my reservation is when I want something to sound like the original, and then I would be less likely to use it.
I see. Thanks for the explanation
DeleteI built a fuzz face type circuit with the 7660S providing 9v- and got excessive noise. I tried several of the usual fixes for noise and the only thing that worked was ditching the charge pump.
All of my voltages looked good but it was just really noisy with that charge pump. For better or for worse I mostly lost interest in them after that
Does anyone here have information about the charge pump problem? I've built a Klon and a Rangemaster with a 7660S from CPC, both are unusable because of noise and probably HF oscillation. Are there any 7660Ss that are more likely to work? Cheers
DeleteO wow, that schematic for the switch is really cool!
ReplyDeleteAlso thanks so much for listening to my suggestions! I look at this site everyday you guys are my favorite
ReplyDeleteVery excited about this! I was planning on build a new rangemaster soon. I love the Idea of the switchable caps too.
ReplyDeleteFor anyone wanting to try the switchable caps in this or any of the other effects, this is a pretty good price:
ReplyDeletewww.ebay.co.uk/itm/190934769333
With it having the same split shaft as the pots we often use we could use the same sort of knobs and for this effect I think it would look quite cool to have a 2 knob Rangemaster with the usual Boost pot and a 3 position Tone control next to it with the same chickenheads or whatever.
Hi Mark, may I ask layouts using cheaper chargepump like NE555?
ReplyDeleteYou can't do it with an NE555 I'm afraid, the largest negative voltage you can get from a 9V supply is -6V so it just isn't suitable for the circuit. You can get the ICL7660S cheaply though, here you can get 10 for $4 which will let you build a lot of these effects.
Deletehttp://www.ebay.co.uk/itm/370536923495
Ok thx Mark
DeleteHi Mates,
ReplyDeleteMy experiences with the 7660S and its different configurations are not all ok:
- With the Klon, used as doubler, sounds great and no noise.
- With the Mutron III: sounds great, no noise at all
- With the Meatball: perfect sound, no noise at all
- With the OKKO Diablo: Infernal whine when set to 18v, totally useless.
- With a Fuzz Face: (as inversor) Noticeable noise, and tamed fuzz, not recommended.
- With a Tonebender MKII: (as inversor) Noticeable added noise and slight oscillation when gain is al high values. Not recommended.
So, in my opinion, this ic is not recommended at all with germanium builds as inversor and neither medium - high distortions as doubler. The only overdrive - disrtortion effect where I have had no problems, has been the Klon.
Of course, this is my experience but I'd like to share it.
J.
Thanks for the feedback guys. I wonder whether a different IC like the LT1054 would do a better job. A bit of experimenting may be called for.
DeleteI've made a few Tonebenders with the voltage inverter and have never had nouise or oscillation. And a few Ge fuzz faces with it too. That's just my experience. Although when I used a cheaper power supply, I had noise on the Fuzz face.
Delete*Noise. And to add, I've always used the 76605
DeleteYeah that's been my results too mate, never had one issue other than when I bought a non-S version by mistake once.
DeleteYeah, first time it happened to me, I thought it was a defective batch, so I purchased another lot for a different seller, even though it was the same ones that used for the Klon and the Mutron III (a 100 pieces order). Had same results (npise) with the Okko and the Tonebender using the new batch, so I'm right now building a new MKII without inverter, and never built another Diablo :)
DeleteI did read someone say that the Openhaus sounded awful with a charge pump to get the 18V and you should always use a dedicated supply or just run it at 9V. So some circuits are obviously sensitive to it.
DeleteI've never gotten a MKII Bender to work on a power supply at all. It's always super noisy and oscillates. It's probably just my power supply, but since I use a one spot or BOSS PS I figure many others would have the same problem if I sold one that way
ReplyDeleteany suggestions for the Hfe transistor? Thxs!
ReplyDeleteAny pnp transistor with an hfe between 80-100 would be fine. Leakage 100-200 micro amps. :)
ReplyDeleteICL7660S version with tone switch is verified. Used a Russian Mn39b (hfe 39) and C5 68n. No noise whatsoever.
ReplyDeleteAwesome, you're on a roll! :o)
DeleteDoes it sound good with such a low hfe? I don't care too much to pick my transistors in the suggested ranges as long as it sounds good, but that's pretty low.
ReplyDeleteI guess I should just put a rangemaster on my breadboard to find out for myself :P
Because of the low hfe there is not a whole lot of boost like you would have with a higher hfe including lots of gain. However there is a slightly cleaner boost which is useful in combination with the tone control. Basically the version I made is a simple EQ with three settings. Perfect in combination with a tube amp.
DeleteHello!!
ReplyDeleteI'd like to know how to adjust the trimmer.
You're all are doing a brilliant job¡¡
Welp, despite what I said earlier in this thread, I went ahead and built up the charge pump layout
ReplyDeleteIt works perfectly of course, although it's too late for me to really test such a loud circuit. There doesn't seem to be an unusual amount of noise or anything with the boost set at max.
Seems pretty much good to go but I'll swap around different transistors. Right now it's got a 2SB422
Alright so I just cranked it up and threw a few different transistors in there. Everything is sounding good. REAL good even.
ReplyDeleteI set the collector to 6.66v as Mr Main suggests and it sounds pretty damn good. Even if I blindly swap transistors without re-biasing, it sounds excellent. There's little noise except a quiet high pitched oscillation. The oscillation is quiet enough that I'm hoping it will disappear once I box the circuit/use a better power supply
I still don't think I'll use a charge pump with circuits that don't already include power filtering caps but they're pretty great
Nice one. If you're worried about the filter cap because we have known times when larger caps have tamed fuzz, then just try something lower in there like a 1u as in the Klon instead of 47u (or whatever). It should still work but hopefully without affecting the character of the fuzz, and if the original didn't have a filter cap then excess noise from the lower value definitely shouldn't be a worry.
DeleteMaybe it's just a case with some circuits to use whatever cap will allow the charge pump to work as intended even if it isn't a value you would usually select if its main purpose was as a filter cap.
Been kinda playing around with different values for a b-c cap to reduce noise and shave off any harshness
ReplyDeleteIt's working pretty well, and worth a try for you guys.
I just soldered in a little socket by the input cap
Leave the 100k resistor. Put a 2,2uF (I used 1uF and it sounds avesome) in the 5/3 and 3/3 hole. Connect a 100kB lug 2 to 7/1 and lug 3 to 3/1. Lug 1 will be your new input. Voila you have a PNP Red Rooster with negative ground.
ReplyDeleteAnyone have a problem with burning out the IC? I had it working in the enclosure, then in my pedal board with power daisy chained from a boss tuner. When I switched order in the chain the sound fizzed out and it released its magical electrical smell... I started over and this happened again on my next board; fried the 7660S. Replaced the chip and it worked right, but when I unplugged it again and plugged it back in the sound started to fizz out again. Opened it up and replaced the IC once more and it has been working like a nasty beast for a few hours...so far. So what's the issue, faulty IC chips or is there another likely problem?
ReplyDeleteI've fried 6 TC1044SCPA I used for voltage inverters very recently. I'm also clueless about what's the actual issue. Some lasted for may hours, some lasted for seconds, but their death always seems inevitable LOL.
DeleteWill a ICL7660CPAZ work for this? Need to brush up on my voltage IC knowledge but I know I have these in my parts from another build. :)
ReplyDeleteNope, you need a 7660SCPAZ. Without the S you will get an unbearable whine as soon as you plug the effect.
DeleteJ.
Very nice layout. I used a 300hfe OC75. Note that you may have to change the 68k to something lower to get the right bias, depending on your transistor. I started with the 68k and could only get to 6.1v even with trimmer all the way. 43k worked well for me to give some play. 6.8v seems to be the sweet spot, though its a matter of preference 6.6-7.0 is your target. I used a 1044, which is slightly noisy, but I don't have any 7660 right now - the one I did have was a dud. Thanks for this!
ReplyDeleteHi ya, can i use 4.7n caps instead of 5n.
ReplyDeleteSure!
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DeleteI would like to add an on off on toggle switch to this so I can have a varity of flavor of tone but i would to knoe how can I add it up to the circuit. Any help.
ReplyDeleteIn the image of the collector / emitter swap cheat version, one of the 47uf trainers is wrong.
ReplyDeleteThis comment has been removed by the author.
ReplyDeletethank you for these amazing layouts.I would like to add some of my mods on this already amazing and easy build.
ReplyDeleteFirst of all to my ears trannies with the hfe between 130-180 sound the best.biasing this design is very much dependant on the hfe of the transistor so its better done by ear. If you want more output use a 20k pot instead of a 10k and you will also enjoy the extra hair.
For the input/output cap modification, i used 2 on off on dpdts instead of a rotary which IMHO is a more versatile and cheaper implementation of this idea. For input caps i went with mark suggestion but the output caps suggestion didn't make any audible difference to my ears so i went for 2n2 100n 220n.
I'm just populating a board for the "cheat board" and noticed a mistake. The drill at x4 y6 shouldn't be there as it's removing the path to the 47u electrolytic bypass cap. I've checked the rest against the Fuzz Central schematic and it looks fine. I need to re-cut a board and order a few bits before I'll be able to test though.
ReplyDeleteI made the "cheat board" using an NPN transistor and noticed other problems.
Delete- As you said, that cut shouldn't be there
- the transistor pinout is upside down
- the electros are upside down if you want to make it PNP. Keep them that way for NPN.
- I don't see that 100k in any of the Rangemaster schematics I've come across
For the tone switch do I solder the output to the footswitch or the board?
ReplyDeleteI´ve build a NPN versión with an AC127 transistor and switchable input caps, works great. I`ve tried to install 1M ohm pull down resistor mod but it change the tone a little. Don´t know why, pull down resistors are supposed to increase impedance and discharge the input/output caps and not affect the tone. Does somebody knows whay this is happening? Thank you
Delete