Help to 'better' output schematic??

[nad]

Hello,

Here's a simple schematic of my opamp output.


Can anyone suggest any changes for the better? The resistors are the standard 5% type so I assume swapping them for 0.1% RC55Y's would be a start?. Going on the 'less in the path' approach; do I need them all? can I remove a couple and only have 1? if so, what value would be ideal?

I removed all the resistors at one stage and the output became far to mellow so back in they went.


The caps were removed at another stage but it seemed to lack something, although I'm unsure what, So they went back in too.
I know black gates would be good but I'm looking into plastic film. There's a bit of space so it wouldn't be a problem. Anyone suggest a value/brand of plastic cap to replace the ZA??



Thanks in advance,
Ant

[richie00boy]

Not sure why the 4k7 parallel with 75R is there, was there a muting circuit that you have now removed?

It's pointless using 0.1% tolerance resistors for this application.

[peranders]

Why do you have to a cap in the first place? Where does this signal go? What is your load?

[Andrea:]

An electrolytic cap... hmm, I don't know. Better use a space-saving Wima MKS2 4.7uF 63V, for instance.

Also I'd remove all those resistors and connect the capacitor to the output with something like 100 ohm.

[nad]

Originally Posted by richie00boy

Not sure why the 4k7 parallel with 75R is there, was there a muting circuit that you have now removed?

It's pointless using 0.1% tolerance resistors for this application.

Correct, I've removed the muting circuit. Why pointless?

[nad]

Originally Posted by peranders

Why do you have to a cap in the first place? Where does this signal go? What is your load?

I pressume it's a dc blocking cap?

[nad]

Originally Posted by Andrea:

An electrolytic cap... hmm, I don't know. Better use a space-saving Wima MKS2 4.7uF 63V, for instance.

Also I'd remove all those resistors and connect the capacitor to the output with something like 100 ohm.

A polyester cap? possibly. 1/4w carbon 100 ohm?

Thanks

[richie00boy]

OK the 4k7 was part of the muting circuit. You can get rid of everything and just use a 47 ohm 1/4 watt 1% metal film resistor and 47uF or so cap. Or if your input stage it is connecting to has a DC blocking cap you can remove this one.

0.1% tolerance resistors are pointless in this application because they don't affect the signal level to any real degree.

[nad]

Originally Posted by richie00boy

OK the 4k7 was part of the muting circuit. You can get rid of everything and just use a 47 ohm 1/4 watt 1% metal film resistor and 47uF or so cap. Or if your input stage it is connecting to has a DC blocking cap you can remove this one.

0.1% tolerance resistors are pointless in this application because they don't affect the signal level to any real degree.

Thanks,

Andrea (post above) recommends a 100R, which do I go for???

[Andrea:]

Originally Posted by nad

A polyester cap? possibly. 1/4w carbon 100 ohm?

Thanks

If you want it small enough to fit the circuit, yes. I'm using the same Wima caps I've suggested (on a DAC's output) and I find them to be inaudible in the signal path.

You could use a 100 ohm (or also 200 ohm) 1/4W metal film resistor..