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40hz high pass filter - build or buy?

Discussion in 'Amps and Cabs [BG]' started by Edword, Dec 30, 2007.

  1. Edword

    Edword Supporting Member

    Jun 23, 2005
    I read about it here:


    I've never used one before, so I don't know if this is something I can go out and buy, or if I have to find the parts and build one. Any hints would be appreciated!

  2. bongomania

    bongomania Gold Supporting Member Commercial User

    Oct 17, 2005
    PDX, OR
    owner, OVNIFX and OVNILabs
    I use a parametric EQ unit for this purpose. TB'er fdeck makes a small preamp with highpass filter for sale, but I've never actually seen or used it. Also there was some talk of one of the boutique amp builders (Bergantino maybe?) making a small standalone filter, but I don't think it "exists" for sale yet.
  3. Edword

    Edword Supporting Member

    Jun 23, 2005

    Thanks for the info.

    Eminence makes high pass filters, but I couldn't find a 40hz model. that's why I wonder if I'll have to end up making one.
  4. A9X


    Dec 27, 2003
    Sinny, Oztraya
    Do this electronically at line level inserted in an FX loop or between pre and power. A 40Hz passive filter with a decent slope is going to be expensive, big, heavy and unless well made and specified, a power hog.

    If you can solder and build electronic gear, I can point you to some sites that will show how to DIY. Rod Elliot's for example.
  5. Edword

    Edword Supporting Member

    Jun 23, 2005

    Much obliged!
  6. el_Kabong


    Jul 11, 2005
    If you can pick up one of these they sound decent, are very cheap, have buckets of switchable eq as well as a variable HPF and LPF. I think Alto make a similar box.
  7. synaesthesia


    Apr 13, 2004
    You can get an electronic crossover and patch in your efx loop or before your poweramp. There are several rackmounts ones on the market but for your purpose you might look into the small ones that Samson make. e.g.:

    FWIW, unless you have high powered amps feeding subs, or at the very least something in your source or loudspeaker system that is demanding at 40hz, you'd notice very little difference. Electric bass guitar's or EUB's low note character is largely in the first harmonic, i.e. roughly 70 hz - 100hz and most commercial made-for-bass-guitar speaker cabinets drop off well above 40hz.

    These days most people have some kind of HD recording system of some sort, even primitive freeware ones will allow you to record your instrument on your laptop. Most will have some sort of filter or shelving EQ. Play with that and see if it actually makes a difference to your ears or your reproduction system with your given instrument's pickups.
  8. Curtybob


    Jun 2, 2007
    Jackson, MO
    I can see the need for one. My power amp has a 30 hz high pass built in. Without it on, it sounds fine. With it on, boominess is more controlled, and I get a good bit more volume at the same settings.

    So is it needed? I think no... but I think it's a good addition to your rig.
  9. unlined4string

    unlined4string Supporting Member

    Mar 18, 2000
    Baltimore County, Md.
    Many of the better graphic EQ units have a built in switchable high pass filter. The Ashly MQX1310 high pass filter is set at 40 hz and it works very well. I highly recommend this unit. Of course it provides much more functionality than just high pass filtering. If cost is a concern they can be found used at a reasonable price.
  10. greenboy


    Dec 18, 2000
    remote mountain cabin Montana
    greenboy designs: fEARful, bassic, dually, crazy88 etc
    I've usually had a few EQ units around that can provide switchable or configurable HP filtering. But the best I've had by far is the Peavey VSX 26 speaker management system, which pretty much makes the DriveRack PA seem like a bad dream. It's currently in my bass rig and I have to say it's good at doing the Bergantino IP thing too.