wet/dry audio effect how-to?

[dfcarney]

I'm looking to build a piece of hardware that I can attach to the effects loop of my mixer (a Vestax PCV-275) to achieve the "wet/dry" effect that's typically available on more expensive club mixers.

I've been searching the web and I haven't been able to find much in the way of the theory behind the actual effect. The best explanation I've come across is that it's an "introduced delay inversely proportional to the frequency". I.e. lower frequency components are delayed less, whereas higher frequencies are delayed more. Either way, I'm not even sure if this is true because I can't corroborate this with other sites.

Does anyone know the theory behind the "wet/dry" sound effect? Also, does anyone have any information as to recommended implementations? I've got some experience with digital hardware and DSP programming, but I'd like to take this on as an analogue project.

Thanks in advance.

D. Carney

[dfcarney]

Update and correction:

I believe that what I want is a dispersive filter. Can anyone confirm/deny this?

Also, I meant an "introduced delay proportional to the frequency", not "inversely proportional".

D. Carney

[pinkmouse]

I am unfamiliar with the effect, but frequency dependant delays are definitely DSP fodder if you ask me. An anologue solution would likely be very complex and very large.

[dnsey]

Wet / dry is usually used by engineers simply to refer to with / without effects - commonly in relation to reverb. The actual FX may well vary, so we'd need more information about your spacific requirement. Is it similar to the common consumer DSP 'hall' FX, or something else?

[dfcarney]

Originally posted by dnsey
Wet / dry is usually used by engineers simply to refer to with / without effects - commonly in relation to reverb. The actual FX may well vary, so we'd need more information about your spacific requirement. Is it similar to the common consumer DSP 'hall' FX, or something else?

The "underwater" effect is what I'm looking for. I.e. not so much reverb as filtering (and potentially delaying) specific frequencies. I.e. a variable, "muted" kind of sound.

I do tend to agree with 'pinkmouse' (above) in that it'll likely have to be a digital (DSP) solution. The idea of something analogous to an FFT in analogue hardware sounds like a nightmare. Then again, I haven't done the research because I don't know exactly what I'm trying to do... Maybe it could be done with a simple RCL network

D. Carney