[sdiy] Best & fastest envelope follower schematic.. anybody ?

Tom Wiltshire tom at electricdruid.net
Thu Dec 16 01:23:40 CET 2021


> Begin forwarded message:
> 
> From: Mr&MrsAccount <hbissell at wowway.com>
> Subject: Re: [sdiy] Best & fastest envelope follower schematic.. anybody ?
> Date: 15 December 2021 at 15:19:38 WET
> To: Tom Wiltshire <tom at electricdruid.net>
> 
>  
>  
>  
> The worst case for the envelope follower is at the lowest frequencies, 80Hz for guitar.  That is where the ripple is the greatest. If you make the filtering
> slow enough to filter 80Hz there is a very long tail when the input signal goes away.  The normal guitar decay can be as long as seconds... but if you stop the strings
> if can be MUCH shorter, and the classical approach will still allow the envelope to decay slowly.
>  
> The reset clock should be set to about 100Hz  (not 8KHz).   
>  
> Its easy to filter the high frequencies and there is no benefit to the circuit for short tone bursts like in the comparison paper. The circuit is also not the best for triggering
> on an input signal where the lowest frequency is unknown or cannot be specified (like wideband music etc.)  It is intended for something like guitar or bass.
>  
> Harry Bissell
>  
> From: Tom <tom at electricdruid.net>
> To: Mike <mbryant at futurehorizons.com>
> Cc: rburnett at richieburnett.co.uk <rburnett at richieburnett.co.uk>; synth-diy <synth-diy at synth-diy.org>
> Date: Wednesday, 15 December 2021 7:05 AM EST
> Subject: Re: [sdiy] Best & fastest envelope follower schematic.. anybody ?
> 
> Some envelope generators do feature a "Decay" pot to change the time constant of the filter. 
> 
> Depends on the use case whether that is worth it. In a bit of studio gear where it might get used for various sources, yes, it probably makes sense. For a stompbox where the input is going to be a guitar, you have more knowledge about the signal and you can optimise the design for that. 
> 
> 
> > On 15 Dec 2021, at 11:37, Mike Bryant <mbryant at futurehorizons.com> wrote: 
> > 
> > Why not have both fast and slow filters, and a blend pot between the two so you can find the best trade-off for the incoming signal ? 
> > 
> > 
> > -----Original Message----- 
> > From: Synth-diy [mailto:synth-diy-bounces at synth-diy.org] On Behalf Of rburnett at richieburnett.co.uk 
> > Sent: 15 December 2021 11:21 
> > To: Tom Wiltshire 
> > Cc: synth-diy at synth-diy.org 
> > Subject: Re: [sdiy] Best & fastest envelope follower schematic.. anybody ? 
> > 
> >> With such a simple filter 
> >> there *will* always be a trade-off between speed and ripple. 
> > 
> > Or to put it another way... Increasing the order of the filter gives you a more favourable trade-off between speed of response and residual ripple. 
> > 
> > -Richie, 
> > 
> > _______________________________________________ 
> > Synth-diy mailing list 
> > Synth-diy at synth-diy.org 
> > http://synth-diy.org/mailman/listinfo/synth-diy 
> > Selling or trading? Use marketplace at synth-diy.org 
> > 
> 
> 
> _______________________________________________ 
> Synth-diy mailing list 
> Synth-diy at synth-diy.org 
> http://synth-diy.org/mailman/listinfo/synth-diy 
> Selling or trading? Use marketplace at synth-diy.org

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://synth-diy.org/pipermail/synth-diy/attachments/20211216/063ccdaa/attachment.htm>


More information about the Synth-diy mailing list