High quality high pass filtering for speakers?

Is there a good option for high-passing the speaker connection in a high-end system? 

I want this for a few reasons.
1. NO loudspeakers will come close to a really good standalone sub. Even $20k + speakers end up with really bad distortion at 50hz.
2. My sub has 3 parametric EQs, which helps tremendously in dealing with a 12db spike I have around 60hz. It's no help at all if the speakers are playing that frequency.
3. Even with 2-way speakers, there is still a lot of overlap between sub and speakers without a high pass. Not ideal.
Your comments about a good sub, well integrated are not wrong.

So, no high pass filter is a brick wall. If your 2-way is sealed, and you add a 2nd order filter you end up with a total 4th order. Pretty steep, 24dB/octave.

That is how THX attempts to do things, with 80 Hz satellites, and a matching 24dB/octave lp on the subwoofer.

The best way to do this is before your amp. Either using a miniDSP type of solution, or an analog system like Bryston's crossover. The advantage of the miniDSP route is unlimited EQ and time delay being available at both high and low pass.


Should say it also depends on what you want to fix.

If you want to minimize your main amplifier's output, you want an active crossover before the amp.

If you want to perfect the integration between your sub --> room and sub --> satellites, a miniDSP on the sub alone will do it for you. :) requires measurement and iterations.


OP--Don't disagree with anything Erik said.  I don't know what speakers or sub you have or how high-end it all is.  Some folks have had success with using a high-pass out of the sub, usually around 80hz if it has it, at least to the point that the benefit outweighs potential nasties.  I haven't tried them, yet, but was considering FMOD inline high pass--at least one person indicated they worked well and were transparent.  Cheap to try.

Right now, I'm using an old NHT X2, which is working well.  There seems to be a slight bit of tone-suck, but the benefits far outweigh it.  These are difficult to find.
I would love to try the FMOD, but they are RCA only and I'm using XLR.
OP--too funny.  I was looking for just that, an inline high pass XLR, before moving the X2.  Seems someone should sell them.

Someone around here suggested that they would be easy DIY.  But not for me.  DIY+me=certain disaster.
ive build a DIY Pass B1 pre amp and integrated at line level a 1st order high pass. by changing a resistor, I can change the cut off setting. for highpass under 100hz, highpass at line level is the only sensible way to do it. with a switch I can bypass the high pass. my test indicate this method is absolutely transparent and only bring benefits to my small P3ESR.

it transformed my p3esr, some sounds were blurried and is now revealed, its like a layer of details emerge. the p3esr w/ highpass + subwoofer competes with my shl5+ in most ways

If a 1st order (6dB/octave) high pass crossover is steep enough for you, all that's required is the installation of a capacitor on your power amp's input jacks. The value of the capacitor plus the amp's input impedance determines the "elbow" frequency of the resulting filter. The formula for determining the capacitor value needed to achieve the desired frequency can be found via a Google search.

If you need a steeper slope (2nd, 3rd, or 4th order---12, 18, or 24dB/octave), you'll need to go active. Pass makes a great one, but it's not cheap. Bryston's is somewhat lower priced, but Nelson Pass makes an economical one (retail $1500) in his First Watt B4, a great little unit featuring 1st, 2nd, 3rd, and 4th order filters in 25Hz increments from 25-3200Hz, for both high and low pass, The filters are implemented via discrete components, no IC's or Opamps. RCA jacks only, no XLR/balanced version available.

Vandersteen Quatro are way under $20k and have a fantastic built in powered sub with 11 bands of analog EQ
and are phase and time correct with pistonic drivers
a pair of 5a ( no longer in production ) with push pull aluminum cone subs are around used for $8-10k
the 5a carbon is still in production
all the bass amplified vandersteen products come with very carefully engineered hi pass filters and correction for the built in sub amp

i am biased

JL audio CR-1
I use the JL Audio CR-1 with two JL Audio Fathom f100v2 subs and ATC SCM50 active speakers. After both bass trap and other passive acoustic treatment and digital correction from subs, I can't imagine anything sounding better with incredible seamless integration of subs and speakers.