Tower with good bass extension vs. stand-mount with a sub?

[terryforsythe]

Looks to me like you have frequencies that distort to 1% below 30 Hz

Looking at the measurement, the harmonic distortion below 30 Hz predominantly is 2nd order (red line in the graph). So, for signals below 30 Hz the distortion content predominantly is below 60 Hz. Definitely not localizable as the wavelengths below 60 Hz are longer than 5.7 m.

Also, I'm not confident that all of the distortion indicated in the graph is from distortion of the subwoofer itself - the walls of the room, as well as things in the room, vibrate when the sub is playing low frequencies. Their noise is picked up by the microphone and probably reflected in the harmonic distortion measurement. Obviously, those noises will not be localized to the subwoofer.

 

[Multicore]

trade-off's between large tower speakers and stand-mount speakers combined with a sub

when we were facing this same decision a few years ago, the decision was made more than anything by how to physically fit the boxes into the room. it would have been possible to use subs but it wouldn't have fit the room so well.

refer to the top picture here https://www.audiosciencereview.com/...o-amplifier-review.48196/page-22#post-1821146

the big book shelves ether side of the projection screen were given. between those was a shelf unit like the one you can see but with 4 doors. replacing that with the same kind of thing but with only 3 doors created the two spaces to put the speakers. relative to this, bookshelves with subs would have been a lot more fuss and the advantage not so obvious.

 

[rynberg]

Interesting. Because one of the additional thoughts I am having is whether something like the LS50 Meta is enough with a sub, or something like the R3 (with the additional driver and better lower frequency response) still adds value. Seems like the later, in your view.

I prefer 3-ways to 2-ways for multiple reasons. One thing you can do for a few popular speakers like this is to check out the multi-tone distortion without a subwoofer - Erin at Erins Audio Corner measures that and you can see what the distortion profile looks like with the LS50 Meta and R3 Meta, actually I'll paste below. You can see just how much more output capable the R3 is compared to the LS50, even high-passed at 80 Hz -- pretty dramatic difference!.

LS50 Meta

R3 Meta

 

[wwenze]

The issue is more of product design: Manufacturers hate their front L/R speakers producing anything below 50Hz, regardless of physical size

 

[theyellowspecial]

Went through a lot of different setups and the M16s with sub and room control (Dirac) has been my favorite.

The LS50s are poor for small home theater, even with a high crossover, in case you'll be doing movies.

 

[Cbdb2]

In my opinion, there is almost zero reason to plug the ports on a well-designed freestanding speaker when using a subwoofer, particularly when the port is tuned low like on your F226. For one thing, the response is already down 8 dB+ at the port tuning if you are crossing over at 80 Hz. Secondly, any lumpiness that still resulted even with the decreased output is easily addressed as part of the room correction.

What makes you even consider this in your system?

Thanks for your reply. Just wondered if there where any advantages to plugging the port, like less woofer distortion, and why Revel would even Include them with the speakers if there weren't.

 

[Cbdb2]

At 100 Hz I don't have that issue - the wavelength at 100 Hz is 3.43 m, which is too long for me to be able to localize, especially when music is playing from the speakers. I am using very steep crossover slopes, so that helps.

So if you just play the sub you can't tell where it is with your eyes closed? Its not about the wavelength.

 

[terryforsythe]

So if you just play the sub you can't tell where it is with your eyes closed?

I haven't tried that.

Its not about the wavelength.

It is about the wavelength. https://acousticslab.org/psychoacoustics/PMFiles/Module07a.htm

From that paper:

"For low frequency sounds (<500Hz) with wavelengths >~ 28 inches or >~0.68m (>~ 4/3 of the average head's circumference) the auditory system relies mainly on period-related interaural time differences (ITDs) which are equivalent to single-cycle interaural phase differences (IPDs). Low frequency sounds arrive at the two ears with interpretable phase differences. However, by being efficiently diffracted, they don't result in interaural level differences that are large enough to be perceptible."

 

[Sokel]

So if you just play the sub you can't tell where it is with your eyes closed? Its not about the wavelength.

I can easily tell by voice's proportions,I have tried it to multiple setups with subs away from mains.
As subs go higher in freq baritones mouth's tend to grow like they are caves

The maximum freq keeping them in humane proportions is 80Hz VERY carefully integrated.

 

[andrew]

A lot of good advice in this thread. One issue with the ‘stand-mount plus sub’ model is that some smaller stand-mount speakers start rolling off at circa 120Hz which makes integration difficult. The best results, in my experience, come from a near full range speaker (whether this be a bass capable stand-mount or floor standing speaker) positioned out in the room and subs positioned at the corners / walls.

 

[Andysu]

Dosn't plugging the port change the woofer response, as in adding a peak or dip above the cut off? Arnt you changing the loading of the woofers? I have some f226's and a sub and am thinking about try that.

sealing the port as does with open or closed door ( and window open or closed ) also changes the low frequency

 

[rynberg]

Thanks for your reply. Just wondered if there where any advantages to plugging the port, like less woofer distortion, and why Revel would even Include them with the speakers if there weren't.

It isn't going to reduce woofer distortion, the opposite in fact. The only reason they are provided is for people using them in antiquated systems without EQ in a compromised physical placement -- I mean Revel also provided dual binding posts and EQ switches on the F208 and C208 too, for the same reason (and for marketing). They have no place in modern systems with EQ and with any kind of reasonable placement in the room.

 

[terryforsythe]

The maximum freq keeping them in humane proportions is 80Hz VERY carefully integrated.

It depends on the setup. I use 100 Hz with a 48 dB crossover slope and it sounds fantastic.

 

[terryforsythe]

It isn't going to reduce woofer distortion

It depends on speaker and the port design. On some speakers the harmonic distortion is very high in the bass region (e.g., increases significantly below 100 Hz).

Some ports create chuffing noise. Also, some ports allow some midrange frequencies to emanate out through them. It probably is worse on speakers that have front facing ports as opposed to ports on the rear. On the other hand, having ports on the rear does not work too well for speakers that are placed against the wall.

My speakers have front facing ports and a 6 1/2" woofer. I played with different crossover settings with the ports left unplugged, but the bass never sounded great, regardless of what crossover frequency I chose. Eventually I tried plugging the ports and played with that using different crossover frequencies. What I eventually arrived at as best sounding for my system is the ports plugged and using a 100 Hz crossover frequency.

In another thread I recommended to the OP to try plugging his ports, and he reported that it made his system sound worse. He reported getting the best overall response by leaving the ports unplugged and crossing over at 60 Hz.

So, moral of the story, there isn't a single solution that works best in all systems. Measure your system's frequency response and harmonic distortion, and listen to it, with different settings to see what best works for you and your listening preferences.

 

[Cbdb2]

It isn't going to reduce woofer distortion, the opposite in fact. The only reason they are provided is for people using them in antiquated systems without EQ in a compromised physical placement -- I mean Revel also provided dual binding posts and EQ switches on the F208 and C208 too, for the same reason (and for marketing). They have no place in modern systems with EQ and with any kind of reasonable placement in the room.

What about LF settling time? I've heard sealed designs can have tighter bass.

 

[terryforsythe]

I've heard sealed designs can have tighter bass.

With my speakers, the bass tightened up after I plugged the ports with dense foam. I was contemplating going further and making the cabinets completely air tight, but right now they sound very good, and I'm not sure how much further it would improve.

 

[rdenney]

If the woofer cone vibrates after the signal is over, then that will appear as distortion--output signal varying from input signal. It will also appear in the various diagrams produced by REW as resonant ringing. A sealed design is one way to manage that, but for it to work, the compliance around the woofer cone has to be quite soft. The classic AR/Advent/etc. acoustic suspension speakers of the past used soft foam compliance around the woofer cone, where ported speakers can uses a stiffer (and more durable) compliance. At least, that's my experience.

I always seem to prefer rear-facing ports in ported designs, but I'm not sure I can defend that based on data and certainly my experience sample is rather limited.

But acoustic suspension speakers can also have unwanted resonances and ringing, which is where the term "one-note bass" came from. The term I've always used is "boomy".

And, of course, in the subwoofer range the resonances of many rooms will probably cause a lot more ringing than a one-note woofer.

The solution is not to simply roll off the bass, as a lot of stand-mount speakers do. The solution is to provide broad-banded and smooth response down to the bass region. A lot of speakers went to ported designs to provide more output with smaller drivers, but there are, of course, ways to do it right. I certainly don't hear any boominess in my Revel F12's, which have two forward-facing 8" woofers and a rear-facing port.

Rick "listening in my office to tiny Pioneer BS22LR speakers--no real bass below about 60 Hz but no port chuffing or ringing, either" Denney

 

[terryforsythe]

But acoustic suspension speakers can also have unwanted resonances and ringing, which is where the term "one-note bass" came from. The term I've always used is "boomy".

I suppose if they are poorly designed. But, I have not encountered that issue.

On my present speakers, which are Elac UBR62 bookshelf speakers, any resonances I had were due to the cabinets themselves. I have addressed that by adding fillets of glue to the internal cabinet joints, adding an additional brace and stuffing them with fiberglass. The woofers have a very smooth frequency response with the ports plugged (not a true acoustic suspension, though).

A set of previous speakers I designed myself were acoustic suspension (sealed cabinets). The woofers were Focal 8K415S 8" woofers. They played extremely flat down to 60 Hz. The bass was tight and not boomy at all. The key was the cabinet design. I designed the cabinet to have no parallel internal surfaces, and used a significant amount of bracing (at various angles). Also, the air volume of the cabinet was optimized for the Thiele-small parameters of the Focal woofers, and the woofers had a Qts that made them suitable for use in a sealed cabinet (0.33 comes to mind, but it was so long ago it is hard to remember).

EDIT: I forgot to mention my KEF LS60 Wireless speakers. Their woofers are acoustic suspension. The bass on those also is very tight and clean - definitely not suffering from resonances or ringing.

 

[rdenney]

A lot of good advice in this thread. One issue with the ‘stand-mount plus sub’ model is that some smaller stand-mount speakers start rolling off at circa 120Hz which makes integration difficult. The best results, in my experience, come from a near full range speaker (whether this be a bass capable stand-mount or floor standing speaker) positioned out in the room and subs positioned at the corners / walls.

I agree. This reinforces my earlier point that for many, the objective of using a so-called subwoofer is to provide the woofer the stand-mount speaker didn't provide.

The original point of subwoofers was for movie-watching with surround sound, where the subwoofer was intended to be near the very bottom of the hearing range. Extending it up to over 100 Hz defeats that intention. The first ones I saw were those Bose surround systems with the five tiny boxes and a sub in the middle of the room. Prior to that, people bought speakers with, you know, actual woofers in them.

I'm reminded of the electrostatic Martin Logan speakers I heard at a Best Buy several years ago. It has an electrostatic panel sitting atop a bass driver enclosure. I've never heard anything so disconnected in my life. If a photograph was printed to visually represent what I heard, photographer would call it "soot and chalk". It reminded me of Rick Wakeman's description of Chris Squire's bass EQ--bass all the way up, treble all the way up, mid range all the way down. That's fine for creating his unique sound but I don't want that in a playback system. I'm sure that speaker could have been set up better, but somebody at Best Buy thought that's the way it was supposed to sound. It wasn't just frequency response--there was some sort of time delay between the two parts that forced them to sound separate. And that's probably a setup error.

Rick "remembering when Advent Loudspeakers with their 10" woofers in 12" frames were considered bookshelf speakers" Denney

 

[terryforsythe]

The original point of subwoofers was for movie-watching with surround sound

In the early 1980's, before surround sound for home use became prevalent, SpeakerCraft in Riverside, CA had a subwoofer/satellite speaker system that sold well. Velodyne started making subwoofers for home use in 1983. Also, don't forget car audio where subwoofers were used before then.

But, with the later advent of home theater systems, use of subwoofers in the home did become much more common.