[sdiy] Op amp selection and the box 'o parts

[Ken Stone]

>I generally tell people this:
>
>For integrators for VCOs, use a CA3140 for the high output input 
>impedance. Watch out for the 15 V limit on the pos-to-neg supply.

As already mentioned, the 3130 is the one iwth the 15V limit. 3140 is fone
on 30V.

>For general-purpose synth audio, use TL08x or TL07x.

Audio or DC. unless you need some other specific feature, this is the chip
to choose.


>I've also got some 5532s,

Low impedance, low noise apps, such as 600 ohm drivers.

4558 -
General audio or DC uses, much like the TL07x, just different.

LF353s, 
Same as the TL072. Circuit inside differs a little but some companies will
sell you either when you ask for the TL072.

LM358 and LM324s

Save them for low speed single rail use or slow speed audio or DC summing. 

>Just what is the magic of the 4558?

a "certain sound" that some people like, and then it's only the JRC ones
anyway. Otherwise, i'd not be particularly bothered about it. Serge for
example could use this, a TL072 or an LF353 in the exact same circuit,
depending I guess, on what was to hand.

>I also have a few high-end ones, like OP275, OP2134, etc., but I'm not 
>giving those up unless some a student comes to me and proves they have 
>some mindbogglingly incredible design that would benefit from such things.

If you are making studio quality stuff, then maybe. For home or school use,
pointless.



Ken
_______________________________________________________________________
Ken Stone   sasami at hotkey.net.au
Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
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