Run main speakers full range with subwoofers or high pass mains?

MartinLogan Audio Owners Forum

Help Support MartinLogan Audio Owners Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Dan F.

Well-known member
Joined
Jul 10, 2020
Messages
48
Reaction score
21
Location
CT
With a pair of subwoofers are folks running their speakers full range, or using a high pass crossover to limit the main speakers to 60 or 80hz and above with subs filling in the low range? Which seems to provide best integration? Would the answer be different with CLX, which is -3db at 56hz?
 
Are you saying your have CLX speakers? What subs are you using?

As a very basic start this will be room and equipment dependent.

If you have CLX run them full and crossover your subs where they work with your setup and room.

I realize, this is vague but it is system dependent.
 
Are you saying your have CLX speakers? What subs are you using?

As a very basic start this will be room and equipment dependent.

If you have CLX run them full and crossover your subs where they work with your setup and room.

I realize, this is vague but it is system dependent.
Don’t have them yet but soon. It will certainly be fun to experiment with both options. I’ll listen to them without subs while they break in to understand their sound first before adding subs (which I already have...JL Audio e110s).
 
which I already have...JL Audio e110s).
Then definitely use the subs, I'd cross over at 70Hz or above, as the slopes are shallow, so the CLX will still be reaching down low.
 
Folks at JL Audio recommend high passing the mains (my amp has a built in 80hz high pass) which would mean low-passing the subs also at 80 and using the subs variable phase and level to integrate. Theory being the bass panel has to produce from 350hz and down and relieving their need to produce 80 and lower should result in a more coherent sound. Not sure if the design of the bass panels are such that going full range does vs 80-350 makes no difference. I will try it both ways at any rate - likely crossing subs at 60hz with CLX full range to minimize the overlap.
 
Then definitely use the subs, I'd cross over at 70Hz or above, as the slopes are shallow, so the CLX will still be reaching down low.

Old post, but just for clarification, with the JL e110/e112 subs, when using their built-in crossovers to high-pass to the mains (using the pre-outs to the main amp), JL uses a Linkwitz 24 dB /octave crossover. And this is NOT a set crossover point. The subs crossover point for the pre-outs is variable, matching to whatever you set the sub's crossover point to. If you set the sub to 55 Hz, then the high-pass pre-outs are also at 55 Hz, 24 dB /octave.

On that note, I too use a pair of JL Audio e110 subs (just had the amps repaired/updated after 3 years of the subs sitting in the closet unusable). I run my SL3's fullrange, then bring the JL e110's in for bottom fill, which they do extremely well. I have the subs crossed over right around the 50 Hz mark currently. Still tweaking them however, both settings and placement. The JL's are fed their signal via high-level straight from the Roksan amp. To me, high-level performs much better than low-level (RCA) inputs on subs no matter the brand.

p4000515762-5.jpg


p4000515764-5.jpg
 
I would go the easy route. Try your set up with subs and without. Whichever sound you like better is the one to go with. Remember nothing is set in stone. Experiment on EVERYTHING!! You will be surprised what you find.
 
Chops, as I try to figure out how to integrate subs into my system, I'm happy to hear you say that you feel the high level inputs perform better than low level inputs across brands, as that little nugget gives me more flexibility (for whatever reason, I had always thought running into the RCA's or XLR's would be preferred). Since I am also considering new main amps, I was feeling limited to only considering amps that had a pass thru config to serve my subs via a low level connection.

Also, I have almost the exact same situation with a door in the corner behind my left front speaker/sub. It's probably just the angle of your photo, but it almost looks like your sub blocks the door. Is that a door you use, or does it just stay closed?
 
I previously had SL3 and also combined with JL e110s. I ran them high-passed at about 95hz (RCA our from preamp to e110 then RCA out from e110 to power amp. This was with Krell KAV-250p/250-a combination. I found that freeing up the SL3 woofers from the lower frequencies to the e110s really filled out the soundstage and bottom octaves better than running them full range and low-passing to the subs at 60hz. This 2nd option still sounded good, don't get me wrong, but I had a definite preference for the high-pass setup.
 
For two channel music listening, my preference is for the main speakers to operate at full range and have the subwoofer to take care of the really low bass; I've set the subwoofer's low pass crossover frequency at 28Hz.
 
Chops, as I try to figure out how to integrate subs into my system, I'm happy to hear you say that you feel the high level inputs perform better than low level inputs across brands, as that little nugget gives me more flexibility (for whatever reason, I had always thought running into the RCA's or XLR's would be preferred). Since I am also considering new main amps, I was feeling limited to only considering amps that had a pass thru config to serve my subs via a low level connection.

Also, I have almost the exact same situation with a door in the corner behind my left front speaker/sub. It's probably just the angle of your photo, but it almost looks like your sub blocks the door. Is that a door you use, or does it just stay closed?

The thing is, most people say when feeding your subs a high level input, they take on the sound characteristics of the main amp. This is probably true to an extent, but in my experience, the high level signal simply makes the subs sound/perform better. They become tighter, punchier, more detailed and musical. And I can honestly say, when I was still running the Polk subs, when I switched out the Schiit Aegir amps to the Roksan Caspian amp, the subs did in fact get a little bit heavier in the bass department with a bit more tightness and agility. Something these Roksan amps are known for.

Beyond that, running high level, you don't have to worry about cable length nor do you have to worry about picking up any noise or hum since the signal going through the cable is at a much higher voltage than any air-born electrical noise. And again, the cable quality isn't really all that critical. As long as it's decent quality copper cable, you're good to go. With these JL subs, they use these little plug-in screw terminals that only accept 16 gauge or smaller wire, so I'm just using cheap braided copper lamp cord from the hardware store. It works perfectly fine and still sounds 100 times better than running RCA's to the subs.

And yes, the subwoofer does block that door. I keep it closed at all time, and have it locked just for good measure. It just leads to the hallway, which you can also get to via literally two extra steps going through the kitchen (the door to the left of the left speaker. And when doing some really critical listening, I close that door as well.


I previously had SL3 and also combined with JL e110s. I ran them high-passed at about 95hz (RCA our from preamp to e110 then RCA out from e110 to power amp. This was with Krell KAV-250p/250-a combination. I found that freeing up the SL3 woofers from the lower frequencies to the e110s really filled out the soundstage and bottom octaves better than running them full range and low-passing to the subs at 60hz. This 2nd option still sounded good, don't get me wrong, but I had a definite preference for the high-pass setup.

I've tried it both ways with the my SL3's, NHT 2.9's, Sonus Faber Venere 1.5's, Klipsch Heresy III's, GR-Research X-Statik's, etc, etc, etc. Virtually all of the speaker I have or had, large and small, and always had best results running them fullrange and adding the subs in for fill. But that's just me.

Just curious as to why you had that 35 Hz gap between crossover points? 95 Hz for the SL3's and 60 Hz for the subs?


For two channel music listening, my preference is for the main speakers to operate at full range and have the subwoofer to take care of the really low bass; I've set the subwoofer's low pass crossover frequency at 28Hz.

Wow, a 28 Hz crossover point?! That sub is barely doing anything at that point. What speakers are you running?
 
Wow, a 28 Hz crossover point?! That sub is barely doing anything at that point. What speakers are you running?
As the saying goes, majority (90%?) of music don't contain any low low bass, so I didn't want the subwoofer to interfere with my main speaker's sound, which is Martin Logan CLS II. My subwoofer doesn't have high pass filter.
 
Last edited:
The thing is, most people say when feeding your subs a high level input, they take on the sound characteristics of the main amp. This is probably true to an extent, but in my experience, the high level signal simply makes the subs sound/perform better. They become tighter, punchier, more detailed and musical. And I can honestly say, when I was still running the Polk subs, when I switched out the Schiit Aegir amps to the Roksan Caspian amp, the subs did in fact get a little bit heavier in the bass department with a bit more tightness and agility. Something these Roksan amps are known for.

Beyond that, running high level, you don't have to worry about cable length nor do you have to worry about picking up any noise or hum since the signal going through the cable is at a much higher voltage than any air-born electrical noise. And again, the cable quality isn't really all that critical. As long as it's decent quality copper cable, you're good to go. With these JL subs, they use these little plug-in screw terminals that only accept 16 gauge or smaller wire, so I'm just using cheap braided copper lamp cord from the hardware store. It works perfectly fine and still sounds 100 times better than running RCA's to the subs.

And yes, the subwoofer does block that door. I keep it closed at all time, and have it locked just for good measure. It just leads to the hallway, which you can also get to via literally two extra steps going through the kitchen (the door to the left of the left speaker. And when doing some really critical listening, I close that door as well.




I've tried it both ways with the my SL3's, NHT 2.9's, Sonus Faber Venere 1.5's, Klipsch Heresy III's, GR-Research X-Statik's, etc, etc, etc. Virtually all of the speaker I have or had, large and small, and always had best results running them fullrange and adding the subs in for fill. But that's just me.

Just curious as to why you had that 35 Hz gap between crossover points? 95 Hz for the SL3's and 60 Hz for the subs?




Wow, a 28 Hz crossover point?! That sub is barely doing anything at that point. What speakers are you running?
It was 95hz for high pass setup or 60hz for running full range.
 
Back
Top