[sdiy] Discrete Op Amps

[Gordonjcp]

On Sun, Apr 09, 2017 at 02:03:20PM +0200, Mattias Rickardsson wrote:
> On 9 April 2017 at 12:45, Gordonjcp <gordonjcp at gjcp.net> wrote:
> > That doesn't really happen though.  All opamps sound pretty much the same.  All distortion pedals sound pretty much the same too, and it's really only the frequency response - which is not determined by the distortion "shape" - that gives it a particular tone.
> 
> Quite an oversimplification. Different distortion pedals typically
> have a pre-equalisation that differs, followed by a nonlinearity of
> many kinds, followed by a post-equalization that differs.
> 
> The pre/post equalizations not only shape the "tone" but affect the
> waveshape and hence the result of the chosen nonlinearity, and also
> determine parts of the dynamic behaviour.
> 

Correct.  The way you set the knobs makes far more of a difference to the sound, than they type of opamp you use.

> The nonlinearity (distortion shape) can vary - I can think of at least
> 5 radically different distortion constructions used in commercial
> distortion pedals, and they do give different tones and frequency
> responses.

They don't really make that much difference.  Certainly there's absolutely no point doing all the crazy stuff that the "boutique pedal" idiots do, like having switches to choose which colour of LED you use for the clipper.

These are the sane cretins who swear up and down that they can tell the difference between various makes of the same opamp in a circuit, and insist on buying NOS unicorn shit opamps because Famously Racist English Guitarist reckons he can hear a difference between two different production runs of pedals, even though Famously Racist English Guitarist also claims he can hear the difference between two different brands of *batteries* in his pedals and indeed has so much coke up his nose he can probably hear the individual electrons moving in the wires.

It's all a lot of shite.

-- 
Gordonjcp MM0YEQ