Simultanious multipul outputs

[Phorhas]

If I with to get both an oscilloscope and amp aout from a given FX, should I use a hi InZ - low outZ distribution amplifier with a gain of 1?

BTW, what is the best way to get an amp through a scope? miking (because I guess it really adds the mike's and the mike's preamp own charecteristics to the outcome)?

[R.G.]

?

An oscillloscope is deliberately a quite high impedance, usually 1M shunted by a few pF or 10M and a compensator, precisely so it can be glommed on anywhere in a signal chain and not affect what is happening in the circuit.

You don't need to buffer to drive a scope input at all in any but a few rare cases.

[Phorhas]

Ah... yeah - too much work got me all tierd and forgetful, so I forgot to specify, it's a winscope (for the moment) so it's based on my sound card's input impedence...

Thing is, when I use multipul out put, I can just parallel them? it doesn't introdunce any loading or other harful (sonicwise) effects at all?

[niftydog]

so, what you're asking is; can you use the winscope to probe around the circuit without affecting it's normal operation?

Well, the answer is a disapointing "It depends."

A normal oscilloscope has a very high input impedance so it doesn't upset a circuits operation. However, your winscope input impedance is dependent on the computers sound card, and this is an unknown quantity.

I would suggest that you find and build a buffer kit for this application. Jaycar here in Australia sell a kit that effectively increases the input impedance of your "oscilloscope" and provides protection to the sound card itself.

[Phorhas]

That's why I asked If I needed a buffer in the first place. anyways I'm soon buying an M-Audio Audiophile 2496 card, which will probably give me better preformance than my current trashy card.

So I was thinking of a dual OA based buffer, using the Hi input Z of the Tl072 and great driving preformance of the NE5532. both non-inverting with a gain of 1 - direct coupled. what do you think?

B.T.W 1 - may be even paralleling the other halfs of each
B.T.W 2 - you think I also need an audio isolation Xformer

[Paul Perry (Frostwave)]

If you are just looking at what is normally the 'output' of an effect, the impedance will almost certainly be so low you can stick your winamp input across it.
poking around inside the guts of the effect is a different matter.