Subharmonics into a HPF?

Discussion in 'Effects [BG]' started by jasonmitsch, Jul 23, 2013.


  1. jasonmitsch

    jasonmitsch

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    Hey folks, I have a theoretical pedal question:

    I'm really interested in purchasing a subharmonic effect like the DOD Meatbox or the Mantic Density Hulk, but I'm worried about their speaker damaging potential.

    Would running either of these pedals through a High Pass Filter like the SFX Thumpinator make sense?

    Would this provide me with the sub synth tone without risking damage to my speakers? Or would it remove all of subs that were just added?

    Does anyone use a Thumpinator with an effect like this?
     
  2. winston

    winston

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    I haven't used the Thumpinator, but I use the HPF on my Fishman Pro Platinum Bass DI for the same purpose. Great for taming the low lows of envelope filters, octavers, and synth effects (also has a built-in compressor). I'd personally go for an HPF with adjustable cutoff frequency, like the ubiquitous FDeck HPF.

    I recall an interview with Bill Laswell and Robert Musso years ago, where Musso said he often runs a ~40hz HPF on Laswell's bass after it runs through his DOD FX25 and dbx Subharmonic Synthesizer. Laswell has one of the most immensely enormous bass tones in the history of the universe, so it seems like a "sound" approach. ;) Of course he's also running through a Neve board/compressor, too.

    If the subharmonic is a simple sine wave it may disappear depending on the HPF cutoff frequency, but a more complex waveform (square/triangle/sawtooth) should survive.
     
  3. bongomania

    bongomania Gold Supporting Member

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    The Thumpinator removes everything below 30 Hz, and nothing above 30 Hz (give or take). So if you add an effect that adds content below 30 Hz, then the Thumpinator will cut that right back out.

    Most of the speaker-damaging power of the Meatbox is above 30 Hz, say in the 50 to 120 Hz range.

    I'd suggest a limiter instead, or in addition to rolling back the low EQ knob of your amp.
     
  4. Jazzdogg

    Jazzdogg Less barking, more wagging! Supporting Member

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    I use one of FDeck's HPF/Pre's in conjunction with bass boost and it works very well to fill out the bottom while minimizing risk of damage to my speakers.

    Keep in mind that different high-pass filters have different response characteristics; inserting my FDeck S3, set @ 35Hz, doesn't eliminate everything below 35Hz; it rolls off at 12 dB/octave. When I rotate the dial clockwise, however, the slope changes to 24 dB/octave.
     
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  6. JohnDavisNYC

    JohnDavisNYC

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    I need a thumpinator. I blew both woofers in my Aguilar 212 on the last nerve tour. Thanks to the awesome womp of the WMD Fat man.....

    J
     
  7. winston

    winston

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    "The party ain't started 'til the speaker's blown, no no no!"
    - Spearhead

    :bassist:
     
  8. M Sterling

    M Sterling Gold Supporting Member

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    Same here, except it was 2 GS112's and a Xerograph Deluxe...
     
  9. Hector_G

    Hector_G

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    I recently played a show for the first time in a long time without the MicroThump, and wow, what a difference I noticed. Speakers were working a lot harder than I've seen in a while. It was scary seeing so much excursion.
     
  10. wolffman

    wolffman

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    When playing electronica and dance music live- is there an advantage of those sub harmonics and low low's pumping through the soundsystem so the crowd can feel that deep bass?

    Might not want those freq's going to your speakers, for the reasons John & Mark mentioned... I also just blew out my gs112 with my octavius squeezer> meat box (turned off the compressor) fawrk.
     
  11. Roscoe East

    Roscoe East

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    Important thing to bear in mind: While some hi-pass filters can have extraoidinarily steep slopes, it's almost impossible to have an infinitely steep slope. So subharmonics (sic) that are below Fc won't be completely obliterated; at worst they'll just be severely attenuated. There's definitely an audible difference between a bass guitar that has no information below 40Hz, and a bass guitar through a sub-octave generator followed by a 40Hz HPF with a 24dB/octave slope. That suboctave will be quiet...but not nearly so quiet as to be inaudible.
     

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