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

[Aaron Lanterman]

On Tue, 14 Nov 2006, anthony wrote:

> Actually I really like the way it sounds. I changed the LF353 for a JRC4558DD 
> and now it distorts a little better when overloaded. So I really like it now.

This reminds me of something I've been meaning to ask...

I'm taking my box o' parts to class tomorrow to pass out parts to students 
starting work on their final projects for my synth class.

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.

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

I've also got some 5532s, some 4558s, some LF353s, some LM358 and 
LM324s... when should I tell them to use one of those instead of a 
TL08x/TL07x? When, for instance, when is the low noise of something like a 
5532 important in synth use (or is it? I've seen it on the OB-Mx 
schematic...) Just what is the magic of the 4558?

I've suggested the LM358 and LM324 for control voltage summing since I've 
seen them used in that role on various schematics.

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.

Some of the students are trying some really clever far out things. I can't 
wait to see what they come up with.

I have the best job in the world.

- Aaron

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Dr. Aaron Lanterman, Asst. Prof.
and Demetrius T. Paris Junior Prof.    Voice:  404-385-2548
College of Electrical and Comp. Eng.   Fax:    404-894-8363
Georgia Institute of Technology        E-mail: lanterma at ece.gatech.edu
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