I would also like to see something like that happen as well, but I'm not going to hold my breath that it ever will. Just like many of us here have been hopeful about seeing a MP-3, ever since we heard that ADA was going back into business, and that doesn't look like it will ever happen either.
At the time the MP-1 came out, the trend at the time was for more guitar players to move from stomp boxes to studio, (rack mount) effects, and ADA jumped on that bandwagon at the time, and produced a variety of effects for years before Dave decided to introduce the MP-1. Using MIDI, and incorporating that to create a programmable preamp, which was up until that time exclusively for keyboards, was what made the MP-1 the innovation of the century.
Since that time, MIDI in the guitar domain has proven to be generally unpopular because the majority of guitar players are too impatient to learn it well enough to be able to use it, and rack gear in general has faded from popularity since the mid 90's and hasn't made a comeback either. In fact, the current trend is for everything to become smaller and more simplified. While I still believe it a great idea to have 128 amplifier tones stored in a small box that I can call up at the press of a button, the truth is, and this applies to most of us here at the Forum too, we really only use no more than a handful of presets in any practical performance application. Most guitar players dial in a clean, crunchy, and distorted tone that suits us and basically, use those with whatever effects we like. This was also true with the famous MP-1 users back in the 80's as well. This is why two and three channel amplifier heads are currently the production standard. Kim's suggestion about an amplifier head would probably be the closest we'd see from ADA if they were to go into that direction, and that was where ADA was headed before they disappeared in the 90"s with their combo amps, (i.e. Rocket, Viper, Quad-tube). Maybe in the future, Dave might produce an amp head, who knows?
As far as replacement parts for our rack gear, I have doubts. Many of the components that were used in our rack gear was proprietary and only made while our rack gear was in production. When our models were discontinued, so were these proprietary parts. Those of us who were around when the ADA preamps were on the market and going strong also remember that ADA stopped making effects units within a year or two after the introduction of the MP-1. ADA went from signal processors to amplification systems exclusively. That was because the bandwidth of the ADA processors was not up to par with the more popular and established brand names, and was considered low-end processors. It would have cost a lot more for ADA to re-design their processors to compete with the high-end brand names already out there, and the units themselves would have cost much more than they did at the time.
I'd sign a petition, but as I said earlier, looking at the trend in today's market, I wouldn't hold out much hope for it going anywhere. The closest thing I think we might see from ADA would possibly be a stomp box sized power amp to add to the current line of ADA products to complete a fly rig on the floor, but even that is doubtful.
Just my opinion though, and we all know what opinions are like
Harley