HyperFAST - a Hypercube Based 2-Way

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I think we need to stop and appreciate how much computer horsepower is required to do something like this in real time at 24bits and 96kHz sampling rate (or even 16bits and 44.1kHz sampling rate). The number of convolutions via FFT's is staggering. :D

Are these the same flat responses you showed is earlier? Foobar and plugins is pretty cool.
 
That's where convolution based audio processing comes in. It's like having a "snap-shot" of a perfectly configured 128 band stereo eq where every band is not only adjustable in terms of amplitude and Q, but can be set anywhere between min and max phase. Convolving the music in real time with the correction filter (.wav file) can be done on a netbook. It takes my 11 year old pentium 4 machine over 30 seconds just to process the short impulse response to generate the correction file! I suppose the newer cutting-edge cpu's could do it in real time though...
 
Are these the same flat responses you showed is earlier? Foobar and plugins is pretty cool.

Post #52 and 60 are featuring the same impulse response. Earlier I showed it unprocessed (which is what I always show unless otherwise stated) and the recent versions have eq applied.

I like that my playback and processing are done together on one machine before being sent on for conversion.
 
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That's where convolution based audio processing comes in. It's like having a "snap-shot" of a perfectly configured 128 band stereo eq where every band is not only adjustable in terms of amplitude and Q, but can be set anywhere between min and max phase. Convolving the music in real time with the correction filter (.wav file) can be done on a netbook. It takes my 11 year old pentium 4 machine over 30 seconds just to process the short impulse response to generate the correction file! I suppose the newer cutting-edge cpu's could do it in real time though...

I think convolvers are indeed performing 128 band FFT's at the sampling rate. That is how computers manipulate frequency and time domain. I could be wrong, but the snapshot impulse wav file is simply what provides the 128 different Fourier coefficients for the FFT algorithms.
 
gmad, hat off your correction seems perfect executed and about Hybercube box you shown better distortion profile and enclosure ringing.
That a full ranger act as a piston only some of the bandwidth i thought was a big problem for correcting it as pure as you did thanks it gives hope.
Your setup looks like a good square wave performer, interested if you did measure this.
 
Thanks for the encouragement, guys. This combination of driver, enclosure and correction software provides a higher quality sound than I could have expected, and as a bonus there is enough output for my needs. I wish the machining of the parts wasn't so expensive. I wouldn't mind trying the 5" Fountek driver in the future now that I'm not as scared of metal cones anymore.

I'll try to provide square wave results soon. The easiest way for me to do that would be to just convolve various square waves with the impulse responses I just posted. Otherwise I may not get to it until next week...
 
gmad, take your time the request. In meantime laugh my lucky hit minimum phase setup EQ'ed A10.2 sealed Q~0,6 in a sweep hit 5 random square like waves here attach the best one a 355Hz, to be said the 5 hits all spread out there is no coherency.
Setup was freeware PC based Soundcard Oscilloscope here link Soundcard Scope set to listen UMM-6 USB microphone when in player played wav-file generated and shared by members this domain. Link member Legis two square wave sweep files found here http://www.diyaudio.com/forums/subwoofers/258706-study-dipole-cardioid-bass-horn-37.html#post4058732, and link member bwaslo square wave sweep files http://www.diyaudio.com/forums/full...ll-range-tractrix-synergy-21.html#post4058232.
 

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Wow those are the cleanest square waves I have ever seen. I guessed they would be good based on impulse shape. Is it good like this at 400Hz, 200Hz? How do you capture square waves in REW? It is so impressive that I would have to ask you to describe the details of your EQ method and software. I think anyone who sees this would be impressed.
 
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The lower frequencies look good too - as the freq goes lower, the "horizontal" part gets more diagonal looking.

If it's looks like this seems the box and system set high pass filter funchtion doing that. Did a simulation with a high pass filter at input of a power amp normal DC coupled and normal reproduce perfect square waves at 100Hz. Placed a 3uf and 30uF capasitor at input and now 100Hz "horizontal" part change as seen in attached picture, the higher the filter is set the more diagonal looking, up high in frequency these caps don't influence "horizontal" part.
 

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