[sdiy] removing dc offset

[harrybissell]

Are you trying to remove DC offset so that you can run it into a modular ???

If so (and you have a bipolar supply) you could run the signal into an inverting

summer (opamp) and 'add' in a bias voltage to offset the one that you have now.
So if your 'toy' has an offset of 4.5V  (1/2 of 9V) for instance... sum in
another
offset of -4.5V and the output will be centered on zero volts.

This will work if the offset is constant.

using a coupling capacitor will work also... for bass it may need to be large
(maybe as much as 100uF ?)

H^) harry

gregory zifcak wrote:

> hi,
> i am modifying a toy that has very rich bass, but due to the fact that it is
> run from a single battery supply, there is a dc offset. i've tried filtering
> this with caps of various sizes, but i can't seem to get rid of the offset
> without getting rid of the bass. is there a simple way to do this?
> thanks for any suggestions,
> greg