I figured out a way around the FIR limitations that I think I can live with. I bought an ADAU1466 months ago that I haven't done anything with. I successfully connected it between my BT module and the ASRC input of the 21489.
Still need to do more testing, but looks like I'll be able to use it for phase correction with 5632 taps per channel @96kHz, which put's it at 95% load. I tried 5888 taps at 99% load and it wasn't happy. 5632 taps seems to be enough to do a decent job of linearizing the sub/mid IIR x-over and subsonic filter. I might do a FIR mid/high x-over on the 21489. I still have a lot to learn and it's a bit overwhelming honestly.
Another benefit is I'll have multiple ASRC inputs now. I think another mod I'll try to do is use one of the PCM4202 boards it came with as an analog input for the SA9227 so I can use the unit directly for speaker measurements.
Still need to do more testing, but looks like I'll be able to use it for phase correction with 5632 taps per channel @96kHz, which put's it at 95% load. I tried 5888 taps at 99% load and it wasn't happy. 5632 taps seems to be enough to do a decent job of linearizing the sub/mid IIR x-over and subsonic filter. I might do a FIR mid/high x-over on the 21489. I still have a lot to learn and it's a bit overwhelming honestly.
Another benefit is I'll have multiple ASRC inputs now. I think another mod I'll try to do is use one of the PCM4202 boards it came with as an analog input for the SA9227 so I can use the unit directly for speaker measurements.
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Ok, now I'm (extra) confused. I thought a static sound I was getting earlier was from trying too many taps. It was a clock problem.
Right now, as far as I can tell, it's somehow managing to run two 10000 tap filters at 5081 instructions per sample @96kHz. I thought that wasn't possible? I made a ridiculous EQ so I could tell if it's working, and it is.
EDIT: It even works at 192kHz. What am I overlooking?
EDIT2: Seems that going over 100% just adds delay? If that's the only downside, I'm fine with that to get 10000 taps per channel.
Right now, as far as I can tell, it's somehow managing to run two 10000 tap filters at 5081 instructions per sample @96kHz. I thought that wasn't possible? I made a ridiculous EQ so I could tell if it's working, and it is.
EDIT: It even works at 192kHz. What am I overlooking?
EDIT2: Seems that going over 100% just adds delay? If that's the only downside, I'm fine with that to get 10000 taps per channel.
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