Powering Stompboxes With Dual Supply From A Single Battery

[teleman]

I want to power a single, dual op-amp based stomp box using a single 9v battery to obtain +/- 9v to run these effects. This method, as I understand gives a better signal symmetry & dynamic range than say, a single rail 9v supply!

LT1206,2426 BUF634 are just splitters so one 9v battery would give only +/- 4.5v/rail, hence defeat the whole purpose.

I think I've now narrowed it to a couple of suitable devices to do this;

LT1026
LT1054

My main requirement is that the device itself should sink very low current & should be able to source more than adequate load current.to the circuit. Can you guys recommend any better, cheaper alternatives than the above 2 devices?

Thanks

 

[sreten]

Hi,

Stomp boxes are all 9V for a simple reason, simplicity.
9V is plenty for the dynamic ranges involved.
The supply has no effect on symmetry.
Your overcomplicating the simple.

rgds, sreten.

 

[teleman]

Hi,

Stomp boxes are all 9V for a simple reason, simplicity.
9V is plenty for the dynamic ranges involved.
The supply has no effect on symmetry.
Your overcomplicating the simple.

rgds, sreten.

Well, It's more to do with economy than simplicity, hence it makes more sense to a manufacturer utilizing just one battery rather than 2 i.m.h.o. As for your comment on, I quote " 9v is plenty for the dynamic range involved", In that case I doubt if you had ever heard a "Maxon 808 overdrive" powered by 18v supply or any other pedals driven at a higher voltage or a dual supply other than a single 9v battery! Dynamic range is directly proportional to the supply voltage, so I was taught! No wonder most pedals sound as they do!

http://www.ti.com/lit/ml/sloa090/sloa090.pdf

 

[sbrads]

After a quick look at the LT1026 datasheet I reckon your battery life will be about 25% of normal 9v operation.

 

[sreten]

Dynamic range is directly proportional to the supply voltage,
so I was taught! No wonder most pedals sound as they do!

http://www.ti.com/lit/ml/sloa090/sloa090.pdf

Hi,

Not so. Dynamic range is a lot more complicated than that.
Noise sources and gain structure are both important.

High voltage supplies are useless if the guitar amplifiers
input won't accept swings that use the extra voltage.

rgds, sreten.

The PDF rightly states an op-amps dynamic range does
basically depend on supply voltage in a very simple sense.
It then goes on to complicate the matter, which it is.

 

[teleman]

Thank you sbrads for pointing this out to me! I nearly overlooked this fact! Yes, I agree, it's rather high between 15-30mA max @ around 10v input voltage! However not all is lost, as LT1054 consumes only around 3-5mA for a 10-15v input can easily supply up to 100mA even a high current demanding circuit. I think I'd try the LT1054 instead.