Harmonic "distortion"

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himhimself
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Joined: Fri Nov 13, 2015 9:34 pm
Location: Bloomington IN

Harmonic "distortion"

#1 Post by himhimself » Mon Feb 08, 2016 4:40 pm

Okay, maybe a weird question but after reading in multiple posts how reflex sub cabs can sound louder than horn subs due to the horns being clean and the others adding lots of harmonics, even though the horns have higher spl...
Would BFM subs sound bigger / heavier to the audience if some harmonics were added via a processor? I am thinking this is basically what all the amp modeling effects do, right? And the horn cabs could then cleanly produce the final sound. By selectively generating the order and level of the harmonics rather than getting it all uncontrolled and messy from the reflex cabs, maybe a bit more of that chest thump could be brought out without destroying the overall sound.
Guessing this might only apply to certain recorded material.
Also, for you guys running the dbx driveracks with the subharmonic synthesizer - do you use it, how, and what's been your result?
Sorry if this was a dumb question, but I appreciate the experienced feedback this forum gives - really amazing.
thanks!!!
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CoronaOperator
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Re: Harmonic "distortion"

#2 Post by CoronaOperator » Mon Feb 08, 2016 5:05 pm

You wouldn't want to add harmonics to the whole signal, just the sub frequencies to reproduce a front loaded subs sound. So ... you would have to process the harmonics for just the low-pass output on your crossover. If you fed that signal to your subs the harmonics you just added would just get filtered out from "going around the bends" of the sub. So ... you would have to take that signal, mix it back in with your highpass signal, then cross-over that signal again so that the higher order harmonics would get sent to your tops. That wouldn't sound the same coming from your tops then from the subs. Sounds a bit counter-intuitive to build clean subs only to add distortion back into them.
himhimself wrote:Also, for you guys running the dbx driveracks with the subharmonic synthesizer - do you use it, how, and what's been your result?
I don't use it, have it turned off.
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Bill Fitzmaurice
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Re: Harmonic "distortion"

#3 Post by Bill Fitzmaurice » Mon Feb 08, 2016 5:14 pm

himhimself wrote: Would BFM subs sound bigger / heavier to the audience if some harmonics were added via a processor?
No. The harmonics produced by direct radiators occur above the subwoofer passband. If you want more output in that range, roughly 100-400Hz, boost the EQ in your tops in that passband.
for you guys running the dbx driveracks with the subharmonic synthesizer - do you use it, how, and what's been your result?
Blown drivers are the usual result. :cussing:

appo1999
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Re: Harmonic "distortion"

#4 Post by appo1999 » Mon Feb 08, 2016 6:59 pm

The Dbx sub harmonic synthesizer...must be used with elevated caution. I have 1 36x33in THT, 2 18 x 18 THT's, 2 18x30 Table Tubas powered by 1 Behr. EP2500 and 1 side of a Behr. a600 fed from the dual sub outputs of an Onkyo PR-SC5508. The room is 26 x 22 feet...Application of the synthesizer on dynamic blurays can easy clip your amps and 'bottom out' your subs. The power factor increases substantially. Playing around with various Blurays and level settings the effect can be inspiring.

himhimself
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Re: Harmonic "distortion"

#5 Post by himhimself » Tue Oct 30, 2018 8:08 am

There was a thread recently discussing how low the human ear can really hear that got me thinking about this again. The poster was convinced he could hear down to 20hz and below even though the data would indicate it is the higher harmonics that fool the ear/mind into hearing the fundamental. Someone mentioned MaxxBass, which seems to do exactly what I was proposing in this post a couple years ago. Apparently it is built into many small powered speakers to give the illusion of more bass than any little tiny box should ever be able to produce. Waves makes the plugin, and apparently made a couple stand alone processors back in the early 2000's. Anyone here ever use MaxxBass? Seems like it would be a cool tool to have in the arsenal when wanting to get a little more oomph - maybe just on a track that seems light compared to others in the mix.
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ACUA
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Re: Harmonic "distortion"

#6 Post by ACUA » Tue Oct 30, 2018 8:50 am

It was radian who originally suggested to me that a processor could be used to add in harmonics to mimic the sound of conventional direct radiator bass reflex and then in theory we could do both be clean horn loaded and then tune to sound “punchy”. I find my self very happy doing what Bill said and eq in some midrange punch 80-400hz range. I will use my driverack to add synthesized bass extension under certain situations mostly for songs/tracks that don’t have enough bass for the gig and I will turn it off once the song ends.

As far as hearing 20hz frequencies and below goes, I have sat in vehicles with loads of subs and loads of power and whether audible or physical/tangible with enough pressure the experience is real and an experience I really enjoy. It becomes a wind generator with Rhythm, it’s euphoric. I get how people don’t find value in it. It would take a lot of equipment to create a wind tunnel in a venue that can shake your soul at 20hz but it would be cool.
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