Best Dual Operational Amplifier

[Mark Hammer]

I went with "what ever is waiting and available in my parts Bin"  hehehehehe 4558 it was.

Oh my goodness! I can't believe that you would go with a 4558 for a clean amp!

There are much better dual op amps available, which make a huge difference in sound quality! 

If the OP were designing/building a studio circuit, with a nice +/-9 to 15v supply, I couldn't agree more.  If it was a 9v circuit but going into a 100W amp, where a bit of hiss - made larger - is really annoying., I would agree with you.  But I have yet to meet or see anyone who runs a 1W amplifier clean.  Indeed, the entire purpose of low wattage amps, whether 2-3-tube affairs, or battery operated, is to be able to get to total loss of headroom easily, without having to endure high volume.

Given that context, a 4558 is probably more than good enough.  Probably not good enough for many others, but good enough for that one.