Correct me if i wrong, but 0.4v/us is right how much wee need to process 10vpp ideal 20 kHz triangle waveform. One half-cycle is equal to 10v slew in 25us. Simple calculations give us exactly 0.4v/us to achieve this slew rate. Maybe this parameter is often overrated or requires some special conditions like +-18v power or some specific input impedance range

btw, if slew rate is so important parameter, we can try to replace OA in an oscillator and possible increase frequency range. I'll try to mess up with it later.

--- In Doepfer_a100@yahoogroups.com , Jim Credland <jim@...> wrote:
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> On 3 Jul 2012, at 21:11, Jim Credland <jim@...> wrote:
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> > I chucked the lm324s out of a previous design here, the dirty cheap and pin compatible tl084 sounds lots better. I think the slew rate was killing me. Alright for fast signals as long as the voltages were low, but with a 7v peak to peak signal it's gotta be rolling off at the top
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> Just to finish my own email. I think the 324 is about 0.5v/us, which if my mental math is right must mean it starts to do bad things at about 5khz. I didn't measure the noise - i imagine there are better chips than the 84 for that.
> J
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