Subwoofers make all big speakers obsolete?

[computer-audiophile]

My Adi-2 has a neat screen where you can see the signal level at various frequencies. A lot of classical music proves to have meaningful output in the range 25-40 Hz. This is also audible: my main speakers (Quad 2805) have full output down to 37 Hz but fall off a cliff below that. Adding (3) subs makes an obvious difference.
In my case the system is a stereo system, primarily used for classical music and jazz. However it also serves to provide video sound and is quite impressive even though only 2 channels.
In my experience issues with subwoofer sound all come down to integration, and not so much with the main speakers but with the room. The lower you go, the more obvious room problems become. So in some room and particularly small ones with room modes up to quite high frequencies it may be better to use small speakers without subs. But in a large room...

Good point! Especially many ESL have too little body in the low bass for my taste. I have also experimented with this. As you say, integration is the biggest problem. Not such a big problem today though, since you have lots of tools.

On my JBL Studio 590, on the other hand, I even had to take away some bass by closing off the bass reflex ports with the associated tube inserts.

However, I tried to point out in my example in #378 that even in a very large room, of course, the modes are there.

 

[Gringoaudio1]

The woofer reproduce a part of the mid.

Not if they are crossed over properly. Subs should handle very low frequencies and have a cutoff slope steep enough that no mids are involved.

 

[Kvalsvoll]

Not if they are crossed over properly. Subs should handle very low frequencies and have a cutoff slope steep enough that no kids are involved.

Very important, and often misunderstood. Especially if sub units are placed far away from main speakers, or even in the back, both impulse/transient response and imaging will be compromized if subwoofers are allowed to play up into the midrange.

 

[Trell]

Very important, and often misunderstood. Especially if sub units are placed far away from main speakers, or even in the back, both impulse/transient response and imaging will be compromized if subwoofers are allowed to play up into the midrange.

At what crossover frequency and slope do you think this becomes problematic?

 

[Willem]

Especially many ESL have too little body in the low bass for my taste.

My QUAD 2805s go decently deep (flat to 37 Hz in room) and the bass is impressive, although I decided that subs were still desirable. I think what many experience as lean bass is in fact bass with fewer room modes. Because they are dipoles they excite far fewer room modes, so you don't get the woolly overripe bass from traditional speakers that have not been equalized to cut the room modes. So room integration is key and the traditional complaint about subs and electrostats in my view originates in the contrast between dipole main speakers that do not suffer as badly from room modes, and subs that do. The traditional cure was dipole subs, but those tend to be huge or anaemic. I think multiple subs with dsp room eq is the modern answer.

 

[Kvalsvoll]

At what crossover frequency and slope do you think this becomes problematic?

Depends on the location of sub units. Hearing can detect direction down to around 60hz, and approaching 200Hz it starts to become quite critical. This means a typical subwoofer with crossover say 100Hz and only 4. order low-pass can be problematic. This is solved by additional low-pass filtering, which can be done above crossover.

 

[Jon AA]

Movies are not aiming for "High Fidelity" - and the LFE channel is supposed to have deep thick monster bass - it is all about EFFECTS... distortion is relatively irrelevant... it's all about the BOOM.

I don't agree with that at all. Good movies, at least, certainly do aim for "High Fidelity." It can most certainly be heard in larger, well done systems--a mediocre system may be able to go BOOM fairly loudly but not necessarily sound good. Distortion is distortion, and if it reaches audible levels it is never good. When program material is heavier in bass and thus more likely to push the subs into distortion I'd say it matters even more.

It's not all "just bass" - there are two competing requirements... best case you want your system to do both perfectly, but within a constrained budget, it is quite common to be able to achieve one or the other, but not both.

They aren't really competing though. As you make the subs larger and capable of more output, generally distortion at a given output will go down. Do one and you've fixed the other.

Or are you talking about the type of sub (driver)? It is widely thought many "home theater" type subs that become very inefficient and difficult to drive once you get much over 80 Hz don't sound very good when crossed with smaller speakers at higher frequencies. For quite a few years now a large trend in the DIY community has been using Pro Audio sub drivers with a high BL, etc, that are very efficient and still sound very good at 120, 150 Hz. And yes, the better ones are usually more expensive so if that's what you were talking about I agree.

Crossing everything over to a sub channel at 80hz is a $$ based compromise - a performance based compromise would have either full range speakers all around (5 or 7) with sub(s) for LFE, or seperate sub systems for LFE (focused on SPL's distortion not a major concern) and for the main channels (accuracy is the priority, SPL's no a major concern)

It's hard to imagine having two separate sub systems would end up being cost effective in the end (not to mention space effective). I think most would be better off just getting better subs that can do both well in the first place. Now that more sophisticated bass management is working it's way down to the masses, the prospects for smaller speakers get even better. Now even mid level AVR's (D&M) allow for directional bass management (your front left main is bass managed to your front left sub, etc), and any processor capable of using ART can do this when set up that way, I think the prospects for making small speakers sound better are improving.

Though with better subs and better bass management I do think the prospects for fans of full range sound from bookshelves are improving, I'm with you in the end and still think there are gains to be had by using the largest speakers one can afford/fit in the room.

 

[computer-audiophile]

My QUAD 2805s go decently deep (flat to 37 Hz in room) and the bass is impressive, although I decided that subs were still desirable. I think what many experience as lean bass is in fact bass with fewer room modes. Because they are dipoles they excite far fewer room modes, so you don't get the woolly overripe bass from traditional speakers that have not been equalized to cut the room modes. So room integration is key and the traditional complaint about subs and electrostats in my view originates in the contrast between dipole main speakers that do not suffer as badly from room modes, and subs that do. The traditional cure was dipole subs, but those tend to be huge or anaemic. I think multiple subs with dsp room eq is the modern answer.

Yes, a good friend of mine who has 4 Quad ESL's (2 in parallel) also uses additional subs from Quad-Music Germany:

Subwoofer QA - Shop QUAD Musikwiedergabe

Sub QA. Mit 30cm Höhe und 37,5cm Durchmesser ist der SUB QA sehr kompakt und dennoch leistungsstark. Aus solidem Material sind die Gehäuse speziell auf die Anforderungen des inneren Bass Treibers ausgelegt. Genau wie die Elektrostaten arbeitet der Sub QA als Dipol. Zur Ergänzung der Elektrosten...

www.quad-musik-shop.de

 

[MattHooper]

Good point! Especially many ESL have too little body in the low bass for my taste. I have also experimented with this. As you say, integration is the biggest problem. Not such a big problem today though, since you have lots of tools.

On my JBL Studio 590, on the other hand, I even had to take away some bass by closing off the bass reflex ports with the associated tube inserts.

However, I tried to point out in my example in #378 that even in a very large room, of course, the modes are there.

I got rid of my Quad ESL 63s because they lacked the oomph and palpability. Even when I paired them with the made-for-63s dipole Gradient subs.

I've heard a gazillion panel speakers, but very, very few dipole cone speakers. But the experience with ESLs and dipole subs left me thinking that perhaps it's something about the dipole radiation pattern that doesn't quite energize the room the same way, as even the Gradient subs didn't quite have that same feel as
sealed boxes (or ported).

Still, aside from the quibble about that sense of impact and body, I can't say for sure that I've ever truly improved up on the sound of that set up with the Quads/Gradients. It was just a huge, boxless, "see right in to a new acoustic space" presentation that was sometimes uncanny. But they are also like
2001 monoliths in the living room.

 

[dlaloum]

Yes, a good friend of mine who has 4 Quad ESL's (2 in parallel) also uses additional subs from Quad-Music Germany:

Subwoofer QA - Shop QUAD Musikwiedergabe

Sub QA. Mit 30cm Höhe und 37,5cm Durchmesser ist der SUB QA sehr kompakt und dennoch leistungsstark. Aus solidem Material sind die Gehäuse speziell auf die Anforderungen des inneren Bass Treibers ausgelegt. Genau wie die Elektrostaten arbeitet der Sub QA als Dipol. Zur Ergänzung der Elektrosten...

www.quad-musik-shop.de

Nice! - although I did like the Gradient SW63 subs that were designed as stands for the ESL63's.... - just aesthetically liked the whole integration with the speaker idea...

 

[dlaloum]

I got rid of my Quad ESL 63s because they lacked the oomph and palpability. Even when I paired them with the made-for-63s dipole Gradient subs.

I've heard a gazillion panel speakers, but very, very few dipole cone speakers. But the experience with ESLs and dipole subs left me thinking that perhaps it's something about the dipole radiation pattern that doesn't quite energize the room the same way, as even the Gradient subs didn't quite have that same feel as
sealed boxes (or ported).

Still, aside from the quibble about that sense of impact and body, I can't say for sure that I've ever truly improved up on the sound of that set up with the Quads/Gradients. It was just a huge, boxless, "see right in to a new acoustic space" presentation that was sometimes uncanny. But they are also like
2001 monoliths in the living room.

Yep - and the whole Monolith in the living room thing, led to their exit from our household ultimately.... but in sound quality terms, I was never disappointed (I couldn't find a set of SW63's in Australia, so I stepped up to the 989's, and had 4 monoliths in my listening room, using the 63's for surround)

 

[dlaloum]

Not if they are crossed over properly. Subs should handle very low frequencies and have a cutoff slope steep enough that no mids are involved.

Yes, part of the problem in these discussions, is the constant conflation of "woofers" - which operate within the audible "sonic" range, and often need to extend up to 150Hz or more to mate with small bookshelf/satellite speakers.
The satellites/bookshelves in this category are typically "incomplete" speakers - that cannot operate properly without the participation of their externally separate woofer (eg: Gallo Nucleus Micro )

And true SUB-woofers, which are designed for the SUB-Sonic range, below 20Hz, and extend up high enough to properly integrate with full range speakers (so circa 50Hz maybe?)

If you look at the specifications of the vast majority of "subwoofers" on the market... they aren't subwoofers at all - their range is totally within the traditional woofer range, and doesn't extend into the infra/sub-sonic range. Marketing decided years ago, that a "SUB"-woofer would sell far better than a mere "external" woofer...

 

[EJ3]

In my primo system, I use two larger bookshelves placed on two different subwoofers. I can't imagine a set-up that would be better and more flexible. More of this and less of that?

I do the same but have the same semi custom (by me) 12" ported 2 Ohm subs that my mains sit on (with a 3 degree wedge raising the front of each one off of the subs with anti-vibration material between the subs & the mains.
They are on each side of a fireplace & a foot (back of the speaker) forward about 8 ft apart.
The right one has the long part of the wall that forms the bottom of the L that is the dining room, yet it is aimed from about 2 FT to the inside inside of but parallel to the short wall of the living room.
The left speaker is aimed from about 3 ft from the long wall of the living room, parallel to it. This wall has a curved bay window that 3 people could sit on the inside ledge of it. The ceiling also slope from 12 FT on the right side to 8 FT on the left side. The back of the room has a staircase going from the bottom on the left to the top on the right. At the bottom of the stairs there is a platform that that allows you to take 2 step toward the speakers (about 25 FT away) turn left & go down three steps (with a 12 FT ceiling above you and a partial wall preventing you from seeing the speakers.
So the subs see vastly differing sections of the room, even though they are in the same spots on the sides of the fireplace.
I detect no standing waves in this room, or bass nulls.
There MAY be reasons to move the mains (96" couch end maybe ever so slightly occluding the left main).
But I see no reason to play with moving the subs around.

 

[computer-audiophile]

A former acquaintance of mine, from the time when I built very special highly sensitive full range speakers myself (as an amateur), was Axel Ridtahler. He has developed special dipole subs, for which he also owns a patent. He calls them 'Ripol-Subs'.

I find them very good, have heard them in various places, apart from the fact that I don't need such subs myself. The room is not filled with too much artificial sound energy in the first place, the bass seems very clear and fixed.

Ridtahler: Soundsysteme - Hifi - Audio - Audiosysteme - Subwoofer ... made in Germany

www.ridtahler.de

Picture from his website:

 

[kemmler3D]

I prefer not using subs and I only need down to 40 Hz since I don't listen to church organ music. And these 40 Hz come pretty good without subs.

Do you listen to music with drums? Because all drums (indeed, all sharp transient signals) should have content below 40hz.

 

[chang]

Is this a physical space limitation? "Accuracy" comes from removing nonlinearities in the system, and either analog or digital EQ help there. If you include the range of frequencies covered (and you should), then a larger sub that can go lower would have better accuracy. Distortion also drops with larger systems.

Yeah, a single 12" sealed sub would be way too small for that room.

Yeah, space is an issue. The way the room is setup, the living portion is on one side, with the dining and entrance into the kitchen as well as another room on the other. Distortion would definitely be helped with the larger woofer but I'm not sure most of the music I listen to requires a sub to cover super low ranges

Funny you say that about the 12", b/c I have a 10" sealed running right now with the gain only a 1/3 of the way up and it's almost too much for the listening position (considering my taste).

 

[computer-audiophile]

Do you listen to music with drums? Because all drums (indeed, all sharp transient signals) should have content below 40hz.

I can hear drums very well with my stereo at home, but at my normal loudness level I fall far short of the extreme dynamics and frequency range that big drums and taiko drums would have, for example. This would also not be desirable under normal circumstances, because I do not want to shake the building.

We have already done a house concert where the Xenakis percussion pieces Rebonds A and B were played live in our apartment. I had to warn our neighbors in the immediate vicinity that it would be very loud.

Here is a photo of that performance at our home:

 

[pablolie]

Do you listen to music with drums? Because all drums (indeed, all sharp transient signals) should have content below 40hz.

They indeed do. What hasn't been proven is whether they are necessary for a superior experience when listening to music i.e. whether those make an audible difference and enhance perceived sound accuracy at all. My opinion is they don't, but YMMV etc.

 

[kemmler3D]

What hasn't been proven is whether they are necessary for a superior experience when listening to music i.e. whether those make an audible difference and enhance perceived sound accuracy at all.

An easy enough test if people were willing to participate, we just need to make sure they all have headphones capable of good sub-bass. All you need to do from there is high-pass some good transient content and see if they hear a difference.

Admittedly I tried this myself with a big cymbal crash to see if it mattered. I could see the difference on the spectrogram but couldn't hear it on playback if I'm honest. I expect better odds of hearing a change with bass, tom or snare drums.

 

[sigbergaudio]

They indeed do. What hasn't been proven is whether they are necessary for a superior experience when listening to music i.e. whether those make an audible difference and enhance perceived sound accuracy at all. My opinion is they don't, but YMMV etc.

I don't understand how that's even a debate. Few loudspeakers have the frequency range of a decent sub, and almost no loudspeakers have the dynamic capacity in the bass as a decent sub. A system with a well integrated sub and a good tonal balance sounds very different from two speakers alone, even at moderate volume.