Voltage Doubler

Heady Jam Fan

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9,009
Some pedals double the voltage internally - I looked at some basic info on the components used to do this and it seems fairly simple (though I know little to nothing about tech stuff). If this can be done fairly simply and without taking up too much space, it seems like many pedals would benefit from just this little added circuitry... I think I would want it in my dirt and compressor pedals.

Does this make sense or am I missing something?
 

WhoJamFan

Silver Supporting Member
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2,775
i've preferred every drive that could take 18 volts to be 18volt supplied. Cleaner, crisper headroom with a little more bass and oomph IMHO
 

amz-fx

Silver Supporting Member
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1,916
You can make a charge pump voltage doubler (with a 7660) on a piece of perf, but you need to thoroughly filter out the switching of the chip before sending it to the circuit, or you will introduce noise into the pedal. This is especially critical in high gain circuits like distortions and compressors.

regards, Jack
 

Heady Jam Fan

Member
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9,009
You can make a charge pump voltage doubler (with a 7660) on a piece of perf, but you need to thoroughly filter out the switching of the chip before sending it to the circuit, or you will introduce noise into the pedal. This is especially critical in high gain circuits like distortions and compressors.

regards, Jack

So would this be a simple addition to most pedals? Also, would it be possible to go from 9v to 12v rather than doubling to 18v?
 

Distorque

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92
Some pedals might have 16V electrolytic capacitors, so be careful. You might want to check with the pedal companies to make sure that their effects can handle 18V.
 

Heady Jam Fan

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9,009
Some pedals might have 16V electrolytic capacitors, so be careful. You might want to check with the pedal companies to make sure that their effects can handle 18V.

Yea, that is why I was asking if bumping it up to 12v rather than doubling to 18v would be possible.
 

cj_wattage

Silver Supporting Member
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6,917
So would this be a simple addition to most pedals? Also, would it be possible to go from 9v to 12v rather than doubling to 18v?
Yes, it's pretty easy to add. You just have to make sure that all of the components in the main circuit can handle 18v. The likely culprits are going to be electrolytic caps and certain ICs. This is easy to verify by just reading off the voltage rating on the caps and googling the data sheets for the ICs.

If you want to have 12v as well, you could set up the 18v doubler, and then also add a 12v regulator. Then you could have a pedal that runs on 9v, 12v, or 18v. You need a little more space inside the box to set all this up (as well as add a switch or two), but it's definitely doable.

Madbean sells a PCB that uses a charge pump to either double voltage or supply -9v for positive ground circuits.
 

Heady Jam Fan

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9,009
Cool, thanks CJ. I was thinking that it would be cool to be able to run my TS9 Silver at 12v - I assume that voltage is ok since Analogman sells a 12v adaptor with it. I was also thinking it should be possible on my Retro Sonic compressor, but I am not sure. I wonder if there would be space in those two pedals...
 

cj_wattage

Silver Supporting Member
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6,917
If I were you, I'd get ahold of 12v and 18v wall warts and test things out before you go to the trouble of building the added circuitry into any pedals. You may find on some pedals that the difference is negligible.
 

Heady Jam Fan

Member
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9,009
If I were you, I'd get ahold of 12v and 18v wall warts and test things out before you go to the trouble of building the added circuitry into any pedals. You may find on some pedals that the difference is negligible.

You are probably right - I have heard good things about both of those circuits at higher voltages, especially because I run my first TS9 pretty clean, sometimes I like it totally clean (rolling my volume back), and Analogman also suggests running his Ross clone at high voltage for more headroom and clarity, so I suspect I will like the change. I am kinda surprised more boutique companies don't offer that as an option, since I often read that many pedals work better at higher voltages.
 

jackbart1960

Member
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1,175
Madbean sells a PCB that uses a charge pump to either double voltage or supply -9v for positive ground circuits.
This @ madbeanpedals.com. I've built a couple of his charge pump boards. Very quiet 18v. Cool with most of the Fulltone boxi. That and it has the footprint of a large postage stamp. I have one in in a Altoids box pushing my OCD clone. Peace. J.J.B.
 

James

Member
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2,901
I recently had TGP member SonicVI build me a few voltage doublers, which I use with my Fulltone Full-Drive II, OCD and Fat Boost pedals. I'd been searching high and low for something like this since seeing some similar gadgets on David Grissom's pedalboard.

Here's the ones SonicVI made me:

P1010022.jpg


P1010040.jpg


They're sort of hidden underneath my Korg DT-7 tuner normally...

P1010035-1.jpg


He was GREAT to deal with. Highly recommended!
 
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Heady Jam Fan

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9,009
James - thats awesome! Did he also have the cable running out from the doubler to the pedal? I wonder if he could do one regulated to 12v and how much that would run a good ole forumite ;)
 

James

Member
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2,901
The DC cables I got from a guy named Joe Logsdon, of Logsdon Audio. He has an Ebay store and sells DC cables and power supplies there. His Ebay User ID is joseph2442.

I can send you contact info for TGP member SonicVI via PM if you'd like, or perhaps he'll see this and chime in. Very nice guy! I am very happy with them. I can't say enough good things about him, actually. He was extremely helpful, a pleasure to deal with.

I do like running the Fulltone drive pedals at 18 volts. They're a bit more dynamic, with a bit more headroom. It's subtle, but there is a difference.
 

CodeMonk

Member
Messages
1,676
You might also want to have a look at the data sheets for the IC that does the dirty work.
One popular chip used for voltage doubling is the MAX1044.
It can only supply 10mA of current.
The 7660 IC, not sure what it mA capacity is.
 



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