Hello guys! :)
I've registered so I can discuss about Z-5500 modding.
I too have one system ripped apart at home and doing testing and whatnot with it.
My idea was to create entire new amplifier board with separate 6 amplifiers, using Control Center(pod) as a volume/input control and Dolby Digital encoder. The idea was also to make new speakers just for this upgrade, making the front speakers capable of delivering more low frequency. As I would recreate all speakers and amps for 5.1 system, I wanted to make a smaller 2.0 set which I would also control with the pod.
But, I guess that's not gonna happen...
I've created a new amplifier with TDA7294 and connected it to front left(or right) channel(before op amps in subwoofer amp plate) to check what kind of signals do I get. I used larger speakers, and sound was lacking bass. So I connected it to sub, and it was full of bass but also you can hear some voices...bad 150Hz crossover. :)
Anyone knows how to enable LFE for sub to go to front speakers and lower the bass cut-off frequency from 150Hz to 80-100Hz? :)
I've studied all chips on the pod board, CS42526 is an input selector, maybe it's doing some ADC(assuming all of this), NJW1150 is a volume controller and CS494003 is a DSP, which I guess is doing all the hard work around here(also cutting the frequency).
You can add more bass/treble with NJW1150 on front speakers(needs to be controlled over I2C, bypassing Zilog MCU(I've worked with Microchip, Atmel and ARM but not Zilog)) but the end product would be the increase of frequency of 150HZ and more.
Final option is to use few opamps and mix the sub output to front speakers. Not sure how well would that work or sound.
Anyways, if someone has an opinion on this, feel free to elaborate with me.
Currently I feel disappointed, even if I can control NJW, I can not get a full range frequency on front(or even all) speakers.
Anyone hacked into DSP? If yes, lemme know! ;)
Greetings from Croatia!