2. speakers
  3. 184406-87347

How do you high pass your main speakers?

I have been very happy with the distributed bass array I added to my system, but from what I hear, the optimum method of integration is to high pass the main speakers.

Two questions:

1. What are my options for accomplishing this? Does this need to be a feature built into my amplifier or is there another component that needs to be inserted in the chain. 

2. What crossover point would be ideal? What frequency and amount of rolloff would be best if my speakers are ATC SCM19's which have a frequency response of (-6dB) 54Hz-22kHz.

Cheers,

Tony

128x128tony1954
Post removed 
erik_squires
15,791 posts
 

I always wonder if those users who perpetuate thee idea of not using your subwoofer to the fullest have ever tried it. There’s a desire to maintain the purity of the main speakers without affecting them by using a subwoofer.  They end up getting a fraction of the benefits for the sake of audiophile purity. It's a shame because what they miss out on is so much more than bass.

As someone with hands on experience, and after getting plenty of positive feedback from A’goners who have actually tried it, I believe that most everyone who high passes their main speakers, via a line level crossover of some sort, finds it a wonderful end-result.

In particular with small speakers, removing the two lowest octaves can greatly reduce the distortion, not just across the bass but well into the midrange, so the speakers sound more transparent with improved soundstage, and eliminating the bass also increases the speaker’s dynamic range a great deal. It’s a really life-changing experience.

Even if a speakers output drops it doesn’t mean the cone displacement does, quite the contrary, an effect which is made worse with ported speakers.

If the OP high-passes the satellites and can carefully integrate the subwoofer, perhaps with the help of DSP they will be amazed at the new super-sized speakers they own. :)

Having said that, the OP could experiment with a couple of different capacitor values, say one for 80 Hz and one around the speaker’s natural roll off, which I think is around 55 Hz, or around 0.06 uF, so you could add an 0.022uF to the 0.047 uF and get pretty close. :) With some jumpers you can experiment in real time.

Rep
zlone
418 posts
 

I use the high level connection on my REL T7i subwoofer (i.e. speaker wire connections to the power amp), so filtering between the pre and power amp is not an option. Is there a way to add a high pass filter for my speakers at the speaker wire output of my power amplifier?

mitch2
3,695 posts
 

@mapman 

In particular with small speakers, removing the two lowest octaves can greatly reduce the distortion, not just across the bass but well into the midrange, so the speakers sound more transparent with improved soundstage, and eliminating the bass also increases the speaker’s dynamic range a great deal. It’s a really life-changing experience.

Even if a speakers output drops it doesn’t mean the cone displacement does, quite the contrary, an effect which is made worse with ported speakers.

Well said.  I don't know about "life-changing" but your other points are spot on.  IME, the effect/benefit is greater with main speakers that don't go too deep or don't handle high power well.  I use the Marchand XM446 fully balanced high pass filter and because of the low frequency capabilities of my main speakers, I had them roll it off pretty low at 45Hz.  I roll the subs in about 40-45 Hz and the result sounds great.  Neither of their passive filters, the XM46SB-AA (single-ended) at $325 nor the XM446XLR-A (balanced) at $525, break the bank for a well-engineered high pass filter using high quality parts.  For folks seriously looking at this option, I suggest calling Marchand and getting what you need, rather than farting around with capacitors.

erik_squires
15,791 posts
 

In order to fine tune a subwoofer’s crossover you need to be able to select both frequency and slope of both the high pass and low pass filters independently.

Well.... kind of sort of but no... 😀

@mijostyn in an ideal world we could effectively turn a 2 way speaker system into a 3 way and apply the same amount of thought and flexibility to both the high and low pass filters and integrate a sub just like you would a driver in a speaker cabinet. I do actually favor this approach... but it’s not strictly required if the low pas filter section is flexible enough and lets us apply EQ and control the slope and delay. That is, we CAN get a little hack-y. with the method I suggested assuming I have a DSP to manage the subwoofer from and will achieve really good results.

I do agree that no matter what you do a delicate and fine tuned integration of the subwoofer is essential. After high-passing the mains the remaining issues are relatively minor and QED with good measurements and a DSP.

I keep meaning to do a blog post on exactly how this would work, so stay tuned gang! :) I will put my money where my mouth is and take lots of measurements.

More to discover