I downloaded that paper, M Code, when the SC-57 first came out and browsed thru it and other literature from them, thanks
including product data sheets and tech bulletins. same with Ice amps.
and I still don't think you are right about an Ice "processor" being in the loop taking a digital signal, processing it directly by the amp. the circuit schematics clearly show that DAC's ARE in the signal path BEFORE the amp section & there is NO bypass around them to the amps. you may know a lot of details about the specifics of the relationships between IR & Pioneer but that doesn't mean you were correct in your post in Sept 2012 about how Ice amps worked in the Pioneer design which isn't relevant anyway to the IR amp design Pioneer uses now. sorry....I respect you & your posts greatly and it weren't for this new poster dredging up your old post, I wouldn't have seen it now or decided to respond. I may not know nearly as much as you about how & where Pioneer sources its designs or which Chinese company it uses as an OEM to build them, but facts about the signal path are facts. maybe he & I have misinterpreted what you stated?
that said, I don't proclaim to be able to explain exactly how the class D amp design works in as elegant way as the mfg themselves as you claim I have some inaccuracies. but I do have the facts as to how the circuit design is laid out and I stand by what I stated...these amps, both Icepower & IR designs, use analog signals FROM the DAC's, not bypassing them as you stated. I have both the service manuals from the Ice amp SC-09TX and the SC-57 and know how to read a block diagram
Going back to the Ice amp design, both Pioneer AND Icepower described them as analog switch mode amps. plus, if I have interpreted your statement correctly, that doesn't make sense to me either....if no DAC was needed for a digital amp, why even have them there in the 1st place? what would be needed for all analog signals would be ADC's not DAC's. and the only ADC's that exist are in the 2 channel analog inputs for converting them to digital for DSP digital processing (MCACC, surround modes, etc). and there are NO ADC's in the multichannel analog inputs at all...they've been deleted several generations ago, so how do they get amplified in your described way?? they can't. and clearly, they are
further, if it worked the way you described in Sept 2012 post, why would Pioneer bother to put a special DAC in the SC-68 for the USB input with a special driver for async USB transfer....just a straight path from the PC input to the DSP to the amp would be all that was needed
nope, it can't work the way you described...sorry. if it did, the DAC's would somehow follow the "digital" amps for final conversion to analog to drive speakers, but they are clearly before the amps, in fact before the preamp section itself.
since you posted a link for me & others on the IR amps, you might want to take a look at the circuit diagrams from the Pioneer service manuals
I can post the diagrams for the Ice amp SC-09 if you'd like, also.
people who know my posting history know when someone shows I'm wrong, I'll admit it and thank them. I may be wrong from time to time, but in this case, if I am, please show me
I am not posting this to get into a debate or pissing contest with you or anyone else, I'm just looking to provide a generalized, factual explanation to a poster on the way it works.
and if a poster is just trying to stir up a debate to have some fun (troll?) shame on him
either way, I responded with information at my disposal and I'm done
I'm not interested in a protracted argument. the OP can accept what he's been given or not, but now it seems to me that challenging you several posts ago for a reply on your "claim" somewhat strikes me as maybe trying too hard to provoke a response or debate & I won't play that game either if that's the intent
peace, my man