Awkward Delays

I wouldn't go to all the bother of maintaining a studio full of ancient synthesisers and effects units if I believed they could be adequately modeled on a computer. I firmly believe that an analog tape based echo unit has a sound that simply cannot be achieved in any other way than by sending a signal through analog circuits and onto magnetic tape and so on, and all the artifacts and quirks and degrading of the signal that goes on when you do this are what makes it so interesting and desirable to me

The same goes for the next stage in the development of the delay effect unit - analog BBD chip-based units such as the Ibanez AD 80. They have an equally unique sound and the way the various controls work together [feedback, delay time and blend] makes them very intuitive to use. The AD 80 in particular has a wildness and immediacy that  never ceases to amaze me, and again it cannot be recreated in the digital domain. It uses analog electronics, and therefore any digital model will have inherent compromises and will only be as close to the real thing as the skill of the person designing the algorithm can get, in other words an interpretation by the designer using one medium to mimic another

I want to get some analog delay modules for my Moog modular format system, and also for the Serge modular. I know that Serge made the excellent Wilson Analog Delay, but they are impossible to find and would probably cost thousands to get as you cannot buy Serge modules individually [they are all in 19 inch wide mixed panels]

As far as I can tell there are no current manufacturers of Moog format modules that make true BBD units. There is a COTK delay module that looks absolutely amazing but it uses a digital model inside and as I have been trying to explain I don't want that. So I am looking into [with Big Al] the possibility of DIYing some panels based on the AD80 circuit, but adding a few twists such as voltage control and dual delays and an LFO

Here is the COTK VC delay module

And here is the Serge Wilson Analog Delay

Below is the MN3005 BBD datasheet

3005 Datasheet




Here is the Ibanez AD80 shematic:

ibanezad80




And here is the Ibanez FL301 flanger schematic which has an LFO:

ibanez_fl301_flanger




Here is a very interesting and relevant article by Scott Swartz about his PT80 digital delay model:

pt80techinfo