Discussion in 'Effects and the DSP' started by monohouse, Nov 10, 2007.
frequency splitter low+high mix not = original signal, why ? and how to overcome it ?
I *think* it boils down to how the kX DSP filters work (10K DSP is a 'time domain' DSP, as opposed to a frequency domain DSP - the 10Kx DSP doesnt do FFT's very well either, so, while YES, it *can* do filters... there are better ways.
If using DSP freq splitting isnt cutting it for you, simply use other hardware, like traditional crossovers and BI/Tri amped systems...
All because the DSP is 'capable' doesn't mean its the best method. And I think you may be hearing why its not the best method. But I have to say, Im surprised you were not able to get something you can live with to work with existing kX plugins too. I dunno, do you have golden ears.. ??? or are you using meters to measure results... or did your attempts just fail miserably... others have used kX DSP to split freqs for Bi-Amped sound systems... and didnt report huge problems... ??? Im not sure what you are expecting from what you tried... does that make sense???
What did you try? (a pic of the kX DSP, along with EQ/crossover settings would help understand, and maybe identify if you faltered in your DSP config.)
What are your system requirements (amp specs, speaker specs etc..)
to better and more directly answer your Q...
if you split lows and highs and re-combine them - you'll never see identical signals... filtering audio causes some 'irreversable' (or difficult to rverse) effects. Resonant freqs and phase shifting are introduced that otherwise were not existent. things like that... Can it be overcome? - to *some* extent, but its too tricky for me.
>and how to overcome it?
to not use freq splitters?
I don't understand the question - you don't want the 'sound changer' to change the sound?
Actually for kX's "crossovers" - low+high mix = original signal (except the phase)
noone has prooved that linear phase filters (e.g. FFT or FIR based) are better (whatever this means - "linear phase" is just another buzz-word) then IIR. It's a matter of faith
well - 'better' is subjective, so its not hard to assume, different would be better *for the op*.... and FIR is different than IIR...no? But a more powerful DSP can do FIR that kX DSP can not - right? which was my point.
Are you suggesting changing phase doesn't affect how it sounds???
But, ok - my bad, I shouldnt have mentioned resonance - I wrongly assumed the OP tried *other* kX filters in trying to overcome what he was observing/hearing. I *try* to read minds... but I wont claim to be good at it.
Sorry, of course i did not intend to dispute your answer. In no means.
It was just a half-joking remark. This FIR vs. IIR thing is full of myths and sometimes it's really funny. So what goes next are just same half-joking remark (don't take that too hard too):
>Are you suggesting changing phase doesn't affect how it sounds???
No, what i suggesting is that "not changing phase does affect how it sounds too"
But, speaking seriously, yep, first i'd suggest to try one of kX's "crossovers" (and "frequency splitter" is not a one). And, well, if the op won't get satisfied with result - then he can try to get something with one of VST "linear-phase" equalizers or so.
thanks for all your replies, and yes, sorry that I didn't give you a screen of my DSP configuration and details about my hardware, which now follows:
looks like this forum has problems: "Your file of 38.9 KB bytes exceeds the forum's limit of 1 Bytes for this filetype."
but then since I have my own site for the data I will direct link it:
http://manoa.flnet.org/Pics/clipboard1.png - this is the current configuration
http://manoa.flnet.org/Pics/Clipboard02.png - current config in detail
http://manoa.flnet.org/Pics/crossover.png - this is DSP configuration of the attempt to use frequency splitter as a crossover
http://manoa.flnet.org/Pics/crossover2.png - this is the where I found the problem: there appears to be a "hole" in the frequencies at the frequency which is specified in the splitter, I tried to fix it according to the standard rules, but I am not sure if the standard rules are applicable to the digital rules or the Kx rules or the emu DSP rules etc...
the first configuration is the one currently used, it output to one stereo amplifier which then goes to a passive crossover and then to a 3-way monitors
the idea which I was trying to do is to take a "more advanced" dsp such as the emu10k2.5 from audigy 2 and since it has 3 analog outputs use it as a "digital crossover" using frequency splitters, because: active crossover is better
then I planned to buy another 2 amplifiers and connect them directly
I did not find the "crossover" plugins in the plugins menues, only frequency splitter, could be because I am using 3534f ?
if the "crossover" plug works the same as the frequency splitter and only the phase, are you suggesting that the "frequency hole" is because of the phase ?
>could be because I am using 3534f ?
yep, it's too old.
>are you suggesting that the "frequency hole" is because of the phase ?
it's a bit more complicated. But, in context of the subject - yes.
ok, thanks, I will try the new kx version when it is ready
You do realize that the current version is 3539, right?
actually only recently realized, at the time of writing the above message I thought that the latest version was a beta 3538 which did not have the good plugins
but I do wonder if I were using the SBLive 5.1 value with only 2 analog outputs, would it be a good idea to use it as an active crossover that splits frequencies to only 2 parts ? is there any advantage to a 2-way active crossover than a 3-way passive ?
Hey .. this is my topic i see
I use a compy with 3x audigy 2s for my home thatre setup with ... simply too many speakers and amps, splited low-top on al channels + option for eq on all channels. Sub-sum and so on.
I would say go for audigy 2 or better in ten cases of ten, because of the better ADC possible with them. The ac97 input on the live cards are just horrid ! Too much noise. And thats a shame, the output DAC are actually really good. (if you dont get that ADC from Uwe Beis and jack it to a free spif input, but its cheaper with an audigy 2)
In short: Go for an audigy 2 and the ADC-pluggy and use the UDA codec. Just a quick look at the peakmeter will tell you why.... noisefloor anyone ?
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