Dual opamp for stereo use?

[radiance]

This is probabely a stupid question, but I never came accros a schematic where it was used that way, so here's the question:

Can a dual opamp (like a 5532 for example) be used to process a stereo signal ? (where one part is used for the left and the other for the right signal)
I don't see any reason why not, well maybe crosstalk ....

 

[Mendelt]

If I'm not mistaken i have a D&R dual mic pre somewhere that uses one 5532 for both channels. It sounds allright, not a lot of crostallk. I'll check the schematics when I get home.

I guess board layout is a lot easier when you don't share chips between channels. You can just copy the layout for the left channel to make the right channel.

 

[clintrubber]

Cool, a Dutch thread so far :wink:
And even a Dutch manufacturer being mentioned, what else kunnen we ons nog meer wensen.

The crosstalk-figure of the 5532 between sections is 110dB typ but that's of course depending on freq (figure is @ 1kHz) & soureimpedance etc etc. Assume a first order 'degeneration' over freq (first order cap coupling) you'll still have 84dB typ @ 20kHz. But the datasheet doesn't mention at which gain and from where to where.

But at such figures I guess the PCB-layout, wiring & common PSU-stuff can determine the resulting crosstalk between channels.

Whether or not to share it will obviously depend on the expected applications. If you're sure you'll always use it for XY-stereo I won't expect much influence. If you'll be using one channel on a gtr-cab and the other for a ribbon on some soft percussion it'll be a different story.

I'd avoid the whole issue. And since the 5532 is cheap it can be avoided at minimal cost. But that wasn't your question of course, you wanted to know more about the why, not ?

Groeten,

Peter

 

[clintrubber]

[quote author="radiance"]Can a dual opamp (like a 5532 for example) be used to process a stereo signal ? (where one part is used for the left and the other for the right signal)
I don't see any reason why not, well maybe crosstalk ....[/quote]
It's not uncommon though to see a dual doing a stereo RIAA-amp, but that's most likely because of economical reasons and that it'll be 'good enough'. Vinyl hasn't very much channel separation in the first place.

 

[radiance]

Well, for the first time I will be making pcb's (after learning some eagle moves ) for my project, which will be a 20 channel summing mixer and some......
I'll use it myself as 10 stereo tracks, no panning, no fader but a rotay, two auxes and bus select. But if I want the pcb's to be of any use for other project they'll have to be mono channels, not stereo. So therefore I will not use dual opamps for one stereo channel I guess. There will be some jumpers on each channel so other people can skip or modify to their taste, that is: using them as mono channels with panning for example....