i have a kabd430 and kabd230 from dayton audio i want to run them both together where the kabd230 is running just the tweeters on that amp i know the kabd4100 is the only one that has cascade if there is away i will greatly appericate the help thank you
Hello fda,
I am aware of these amps and I recently designed a 2-way system using the KABD430 board. sounds great. I gave a presentation at a conference using this setup as a demo system. The folks from Dayton were in attendance. 
The problem is that there are no detailed schematics of these boards. I wish there was so mods could easily be done.
There are two approaches you can take here.
1) Take the serial port output from one of the boards, I assume the 430 board, and feed it over to the 230 board's serial input port. You would need to send three wires, LRCLK, BCLK and SDATA. The problem is going to be that the two boards are not on the same master clock. It would not be easy to modify the boards to share the same master clock. They could not share the same crystal, you would have to change it to a clock oscillator module and feed the output to both. This is not too hard to figure out without schematics but still some work. Why is this needed? Because if you feed the serial input port with clocks that do not evenly divide the MCLK then the part will mute the converters. It is an old part so it is a simple implementation for the clocking for the internal system. Our newer parts are more flexible.
2) Just "Y" the audio to both boards. Then setup the filters on each board to filter out what you need for that output. I think this is the simplest way to do this.
Then the other issue is programming the two parts. Again, if we had the schematics we could see if it is easy to change the I2C address for the DSP. Then you could change the address of one of them and then have both DSPs in the same project! Then just link/compile/download would program both parts. The only problem here will be when you want to program the EEPROM. So I guess you are best to just have two projects, one for the 430 and one for the 230 and program them one at a time.
Reach out to Dayton for support on some of this. They have several example files you could use as good starting points.
BTW, I would look at the hardware and reverse engineer some of the design but that would not be an appropriate thing to do on this forum. It is their design so we cannot publish someone else's design.
Dave T
