Uh, is there a difference? I found a spec sheet that listed them both together and didn't even give two different sets of specs. Are they functionally equivalent or what?
They're almost the same part. The only differences come into play at the extremes of the ranges. If you're intentionally distorting by overdriving them, you will be operating in the area where there may be a subtle difference. I use 2N5457s, but I haven't tried the 58s (yet).
This datasheet shows some of the differences:
http://www.onsemi.com/pub/Collateral/2N5457-D.PDF
On the surface it looks like the 57 is a little more sensitive to smaller signals, but it amplifies a little less. I'll be the 58 is the same design, but perhaps with a slightly larger geometry.
There is so much variation among the 57s that it may not matter much.
Take care,
-Peter
Cool. I was bummed that all I have are 457s and the GGG schem for the orange squeezer calls for 458s...For that application, it seems like there shouldn't be an issue....