Hey guys
I was wondering that when it comes to integrating subwoofers with floorstanding speakers, say a tweeter, a midrange driver and a bass driver at the very least, what is your preference:
1) do a crossover of frequencies cutting off high frequencies above a certain Hz to the sub and cutting off low frequencies below a certain Hz to the speakers
2) run the floorstanding full range and try to blend in the subwoofer via it's built in crossover frequency control

For me #1- always...the second choice is a compromise when you
Don't have the first choice available to you.

My opinion.

I always use the proper high pass/low pass combo with subwoofers

Throwing frequencies into mains that will cause distortion or damage is one of the reasons subwoofers were invented. If the bass is better with the mains running full range, then it is time to redo the subwoofer location or add more subwoofers to take care of nulls. The mains might be filling in nulls that happen naturally in rooms, adding a second (or more) subwoofer will take care of that issue to increase smoothness/sound quality while keeping the mains operating in their desired area.

What high pass/low pass filter are you guys using? More and more subs now days don't offer any or only fixed (usually 80Hz) HPF...

I like 60hz for my mains that play down to 39hz but, not sure if there is really a huge difference vs 80hz.

I do know that at 60hz my AVR runs 10 degrees F hotter than at 80 hz!

Yep. I still haven't been able to cure this. Bass is still cleaner, tighter with more detail with speakers only. I've run out of locations to try the subs and there's still two notes on a acoustic bass that loses the detail these are capable of. Sure didn't do this at my last house with the exact same equipment. I'm going to need to move to fix this.

I never claimed it was easy to do!

The lower in frequency your mains or subs can obtain, the crazier the bass response and problems become. My sub hit 18Hz smoothly--for a small couch and located in one specific spot. However, roam around the room and things get worse and i want to reconfigure the room with a larger couch and know full well lightning won't strike twice. I'll be designing and building two more subwoofers (disguised as end tables) and hope three should do it well enough.

One of the things that helps is taking measurements and having bass management processing for each subwoofer. The Mini DSP box can take one input and have four outputs with each one having parametric EQ, delay and phase control. Other options is what I'll be using, a Crown XTi PA amp to drive the subs that also has parametric EQ and delay so I can have endless fun getting all those subs to play nice.

Bass is a pain, the room dominates the equation and the room nodes laugh at all subwoofers--don't matter how much money you throw at the problem. Harmon did a white paper discussing subwoofers, multiple subwoofers and locations--very interesting read.

The weather is warming so I'll start on my sub builds and look forward to the aggrivation--part of the fun, right?

Moving to a different house to get better bass response? I like the cut of your jib, sir!

A few things I will never do. 1) anything that says digital. 2) anything that says Crown or has anything to do with Harmon. 3) EQ. 4) the word AVR. Never ever. The analog side stays analog from butt to nut.

That being said, I wouldn't mind at all if mid-range integrateds, such as Musical Fidelity, Parasound, Hegel, etc., would give us the option of bass management. I would try it as I suspect that's some of the issue. My bass is fine outside of the room. Since my listening room is in the middle of the basement I can try changing the dimensions of the room. Anyway, I'm getting real grumpy over all of this. I almost enjoy the cheap system with the Elacs more. It has a simple single sub and integrates beautifully. It doesn't resolve all that much so it doesn't drive me nuts either. This is almost as bad as something not right with one of the old collector cars and I can't figure out what it is.

Complete Analog stereo receiver, mid-range price too.
Has selectable (60,80,100hz, bypass) ANALOG bass mgmt.
(It does have a USB digital input)
I've been using one in my 2.1 stereo, music only rig for about
5 years. (HK DMC 1000 music server, Sony SACD player and
A mini-disc deck)

https://www.outlawaudio.com/products/rr2150.html

So you like the Elac sub that has a digital crossover with DSP parametric EQ and a Class D switching amplifier?

Well, technically--you could have subwoofers that use passive components to make the crossover and notch filters instead of EQ and a passive high pass filter--that is going to be one really HUGE pile O caps, inductors and resistors but it can be done. Since EQ is used to tame the humps caused by your room, passive components can be made to tame them which add more caps, inductors and resistors but it can be done.

I might be wrong but--I am assuming you don't have a home theater?

To solve your problems with the old Pontiacs, just do an engine swap with an LS V-8 crate motor. Plug in a laptop to tune the fuel injection and electronic ignition and go! I think Holley makes a fuel injection system for those engines and MSD can get you an electronic ignition.

Just yankin' your chain

It is rather odd that they don't put bass management systems in 2 channel receivers...errr, integrated amps (same thing hold the tuner) Then again, most people that use them won't have 4 subwoofers and entertain themselves with paramatric EQ. I guess the demand is not there yet--eventually it might happen.

Exactly, at least give us the option, but still let it be pure analog if that's what we choose. I should see Kevin Hays of VAC at Axpona. I want to find out why. His integrated, the VAC 160se is over $10,000 so it's certainly not because bass management costs too much. I did have at least one SAE parametric EQ at one time and it did some weird phasey stuff and moved placement around in the sound stage, so never again.

Fremer wrote a pretty positive review of this about ten years ago.

http://www.stereophile.com/integrate...YqA8EHgggmi.97

Get off my lawn!

I think the movie was Gran Torino--a classic flick about a dying Korean war vet befriending a Vietnamese family and passing on his life lessons.

A deep bass null at 50 to 70Hz--yeah, welcome to fun with room acoustics--if you listen to your system in the center of the room, I can see that happening. I would move your listening position around and measure it with REW and a USB microphone. Since your problem child is in the subwoofer and mains passband, I'd say running the mains "full range" and the sub crossed at 80Hz would improve that null--might mess up everything else but the null can be filled in.

https://www.amazon.com/Ashly-XR-1001.../dp/B001UIQ1CM

The above Ashly crossover is "analog" in that it has no D/A convertor.

Another concept borrowed from the night club/EDM outdoor fesitvals is using "kick subs". Basically, you have large subwoofers doing 25 to 60Hz and smaller 15 to 18" PA woofers crossing at 60Hz to 150 to 200Hz next to the mains. The deep bass response is different so has it's own response while the mid and upper bass response (the kick) are in their own enclosures with the mains. The idea is to use the kick subs to get the punch and the monster subs to handle the deep low end of modern dance music and drop tuned bass guitars.

This gives a psuedo EQ effect by using the gain knobs--also prevents the deep end from being boosted if more midbass is desired while preventing massive power draws from the monster subs. The home theater guys do the same thing but change the name to "midbass modules" (MBM) The MBMs are up front with the mains and take the 50 to 150Hz range while the monster tapped horn or whatever subs do 15 to 50Hz. The MBMs almost always use PA woofers because they are really efficient, very low distortion and never strain in the home environment. If you listen to classic rock/folk music, the MBM is generally what bass you are listening to as the deep bass subs rarely do anything unless you drop the needle too hard.

The other bonus besides fixing the bass demons is your mains have much less stress on them which is always a good thing.
It would work to keep away from the evils of digital and EQ--but you have some sort of control by using the gain knobs.

It is not easy, it is not inexpensive but compared to moving to another house--I'll take multiple subs and MBMs any day!

http://www.diysoundgroup.com/midbass-module.html

The easiest way to get a MBM is in kit form with CNC milled flatpack box kits. A car audio place in Soviet Monica will be able to put it together easily or a cabinet maker could do it and finish it with whatever finish you desire. A nice option if you plan on placing your mains on top of them for speaker stands.

Good luck and remember, the cure for your engine ills is LS.

"A deep bass null at 50 to 70Hz--yeah, welcome to fun with room acoustics--if you listen to your system in the center of the room, I can see that happening. I would move your listening position around and measure it with REW and a USB microphone. Since your problem child is in the subwoofer and mains passband, I'd say running the mains "full range" and the sub crossed at 80Hz would improve that null--might mess up everything else but the null can be filled in. "


It's not in the center as 50% or 25% are major null points. I'm 73" out along the wide wall in a 16.2' x 18.8 room. I think I've been everywhere in that room. If I go any closer to the front wall then I start to lose the imaging that I have, which is more important. And Soviet Monica is 2359 miles from here.

And it's really one album, but unfortunately that album is one of my top ten. And I run the speakers full range as I have no choice. NO EDM (tweet tweet boom boom, 120 BPM) in this house. The one time I did with Infected Shrooms and Deadmau5 and did it very loud I sent the amp into thermal shutdown. True, it was about an hour of everything it had and man it was hot. So other than showing off to a couple of my grandson's friends to show them that ESLs can indeed do EDM, I don't care to do it for me. I've got the overall bass energy that I want for the genres I listen to except for that one note on an acoustic bass where the detail smears away and a properly recorded acoustic bass has lots and lots of detail. My standard is electrostatic bass so I don't think any cone woofer is going really work for me. Still the problem is that I heard it work very well in the previous house so once heard it can't be unheard. Audiophilism sucks and is not treatable as best I know.

I'm in the blend camp, running your mains full range. I seem to get better results that way. The subwoofer is not supposed to replace your main speakers woofers, it's supposed to operate below where your mains quit. I've tried both but I have never cutoff the mains unless my amp just couldn't drive the mains and I was trying to get more SPL with inadequate power.

Ahhhh, you use ESLs...dipoles

Well, there are dipole woofers that people that use electrostats mesh with them. The servo drive subs seems to be popular with the stat guys--not my thing so don't get me lying!

At one time, I saw some "H frame" subs that are open in the back--I guess they won't sound boxy because they are not in one.

You can go to diyaudio, those guys over there build all sorts of things including electrostatics so would have a better idea what is needed. Good luck!

Do 1. Not many main speakers do well down to 20Hz. Even if they do, the room mode becomes more critical at the bottom few octaves. Subwoofer's advantage is the option to locate for the optimal performance at the listening spot. Besides, by relieving the bottom-end (requires more energy) duty of main's woofers, it lessens the distortion from mains.

There is no set rule for that. It's to aid the lower few octaves of audio output. Crossover point varies depending on room, main's capabilities...etc. Measure the frequency response of both and compare.

I generally don't have much choice given the amps I've used, aside from the times long ago when I bi-amped and tri-amped (Tympanis) with active x-overs. The speakers are cleaner tighter down there so I don't use the subs up any higher than I have to.

Yep, line source dipoles. That's why they do the imaging tricks they do.

These are hard enough to get right and by that I mean really right versus average.

I'm surprised for a HT pub that this guy was really into it. I can relate. I think I'm going to get away from it for a while and stay out of that room.

http://www.hometheatershack.com/foru...er-review.html

http://www.hometheatershack.com/foru...tml#post680654

Very interesting reads and take aways. My reason for this post was to see what most people did and how their experiences have been. Most floorstanding are rated around 35Hz-50Hz on the low end side. Dual 5 1/4 or 6 1/2 inch bass drivers are pretty common and feasible by most.

There are two schools of thought, blend vs crossover. In theory yes doing a cross over may take away stress of lower frequencies but in the real world do that actually 1) make a noticeable difference in the imaging or character of the speakers 2) who is listening to speakers under a regular listening session at ear splitting volumes where the drivers distort or are under tremendous stress? And when how many people are playing music with notes below 25Hz?

I don't listen to most of my music at very loud volumes but yes I do get carried away with volume for some new discovery or EDM or Rock. But the Martin Logan Motion 40 I have hold up really nicely. But I do need to get a pair of subs though eventually.

I'm still experimenting with my setting on and off, but so far, I prefer to run the main towers full range and cross the sub at 80hz.

It might have to do with the fact that I don't want too much bass from my sub due to neighbors situation, so the volume know on a sub is at 9 o'clock position, punching easy and clean, but enough to just make a presence of a sub in a room. And when I run towers full range, it adds to that clean delicate punch of bass without stressing of big "woofing" in the air unnecessarily.
It also helps to blend in the sub so it's harder to localize where the sound is coming from.
It works for me in a small room, but the depending on the space, I'd definitely hope one day to have stereo subs, side by side with towers and then I wouldn't mind to run the towers as "small" crossed at 80hz hehe

I think stereo subs is a more ideal situation but a small step rather than a huge step. The good thing about stereo subs is that they seem to tolerate a higher crossover point and can become audible but they are in the right position to enhance the sound without becoming lopsided. I have run stereo sub towers, stereo subs and mono subs, all were acceptable.

The only real listening time to dipoles for me was my dad's early 50's Altec 12" full-range with wizzer cone and Altec horn with blocking cap and rheostat to adjust all mounted on a large board. Dad liked dipoles but liked horns better--as in corner horns but the basement would flood so 250 pound horns is not a good idea. I also built some dipoles for surrounds, very interesting how they work--whatever works!

In my weird little world of theory--not based on reality of course...hmmm. Maybe a really light cone woofer from the PA world--in a dipole H frame? Some of the folks on diyaudio boards like to use various Eminence and B&C PA woofers, either 15 or 18 and make dipole bins that way. Grab a sheet or two of plywood, make the thing as large as possible and throw a pair of 15's or 18" in there--make a pair or more and lose your mind attempting to make it work.

I'd be lazy and just make a board large enough to seal against the window and let the neighbors deal with the back wave and play with IB systems that way. Just for testing purproses--not permanent unless your neighbors are far, far away.

That's all I got--electrostats are out of my wheel house so... good luck with that!

I'm coming down with my first cold in years .... so that's why I've been such a grumpy ole geezer today.

As I've mentioned on these pages umpteen million times, I started with ESLs in 1959. Dad, who was a MSEE and aeronautics engineer for all of his working life bought a set of Quad EL-57s in 1959. They didn't sound worth a poop back against the front wall in the family room. So one day and when mom and dad were out, I tried pulling them way out into the room, and that did it. Dad agreed. Mom kicked them out of the room. The only place to really put these was in my room. So that's how I got my start with the this near field fetish that I still have today. I think I have as many years with electrostats as anyone on the planet except maybe the late Author Janszen and son David Janszen and of course the late Peter Walker. .

If you want to get into the weeds with dipole theory and practice, have a look at linkwitzlab.com. Siegfried Linkwitz is a genuine expert. The dipoles he has constructed and continues to improve are not electrostatics. He sells plans for constructing his loudspeakers, but he's really not out to make money. I am not a DIY type myself, but I do like to understand something about how my speakers (MartinLogan EM-ESLs) and my room interact. Btw, because of the peculiarities of my living room I do happen to have mine about 10 feet from the front wall.

It is very interesting stuff he does. I still want the nearly massless diaphragm of the electrostatic driver in a dipole line source. Positioning then becomes the bitch. I have see something that's pretty good on the subject and surprisingly on a HT site.

This guy is pretty close.

http://www.hometheatershack.com/foru...er-review.html

http://www.hometheatershack.com/foru...tml#post680654

Thanks. I know both articles.

Much of what worked is below. I think he's absolutely correct that even angle change of a degree can make a major difference.


"Ultimate Soundstage Tuning

The EM-ESL "ultimate" soundstage and imaging have demanding setup requirements. How can one tell if it has truly been achieved? The best answer is achieved with impulse delay matching measurements, using Room EQ Wizard (REW) (or similar analysis program) and a measurement microphone. I got the clearest results with a regular (not USB) measurement mic using REW's timing loopback calibration method, so actual front and rear path delays could be measured directly and arrival times matched to a fraction of a millisecond.

But for a quick means of checking or fine-tuning, a short list of evaluation tracks was chosen, given below along with the particular sonic characteristics to listen for.

Actually, the final treatment method for thickening the soundstage - using horizontal reflection slats mounted along the vertical line below the reflection points on the wall in front of the listener - makes a dense soundstage somewhat easier to achieve. In other words, Example 4 above allows more placement flexibility than Example 3 above, thankfully. With the Example 3 setup, a speaker angle change of less than a degree could make a big difference in the soundstage - from "great" to "average." With the Example 4 setup, such a change would make a noticeable but much smaller difference.

Each EM-ESL speaker had a laser sight mounted on its woofer enclosure using double-sided mounting tape. A target drawn on a piece of white gaff tape on the room's front wall gave a reference point for checking speaker alignment and for evaluating the change to the soundstage and imaging with minor variations in alignment. The distance from the wall conveniently resulted in a one-inch movement of the laser dot roughly equating to a 1-degree rotation of that speaker.

All placement angles and distances came into play, however, including "pitch" and "roll," which strongly affected image clarity. Impulse diagrams show how the alignment of the reflected rear waves is almost perfect for the "ultimate" effect. That alignment of the reflected waves is what one is trying to achieve. It can be achieved by slight rotation of one speaker or the other or by small amounts of movement of the speaker in the appropriate direction.

The dissipation slats were in place for all of this exercise. An additional impulse diagram shows how their presence affects the reflected signal. The difference appears small, but the sonic result is dramatic.

A detailed alignment procedure will be given in another post."

#1 only. #2 is a kludge and I've never heard a system with this implementation sound better than mediocre.