BWC (Big Woofer Club): Why Big Woofers Matter

@k4rstar I’ve neither heard nor heard of a coaxial speaker that didn’t have gross imd in the upper midrange and low treble. The best I heard were the late 90s and early 2000s Tannoys with the super tweeter which were solid yet “pushed.” I’ve even heard from multiple Germans that the Geithains have weird treble to the point of sound pushed, etched, and saturated despite otherwise being great refrigerator sized speakers.

 

James B Lansing himself hung himself. That was after he left jbl though, and had started altec Lansing

Edit:
Also damn what kinda field am I getting myself into in a year...

Edit2: after he left altec and started jbl

 

And it wasn't in the campus, it was at his home in 1949. He left Altec-Lansing in 1946 and started JBL.

And then this ad has been showing repeatedly in Nasvhille.

Spoiler

I know there are a few studios in Nasville with custom built in TAD monitors and laminated wood horns. Including famed mastering engineer Glenn Meadows. Man, they sounded glorious.

 

f**k, size does matter. The 15" Tannoys are like the opera singer whereas the 10" Zu's are like the highschool choir singer. Don't get me wrong, I loved the Zu's and lived with them for 8 years. But the Tannoys are something else. Once positioned right they energized the whole room, and have a taller, higher and wider stage with insane imaging. They engulf you with sound. I also have 6" Omega speakers. Very pleasant and I would be perfectly happy with them, but they can never produce that full stage the 15 inchers can.

 

@batriq your setup is f'ing glorious. Well done.

Something I realized later today that I think why we are at odds with each other: volume. Anything louder than 90 dBL on my SPL meter results in pretty clear bass distortion and compression, and other aspects of sound quality are degraded (like loss of focus with soundstage).

If you want low and loud bass, it can't be small. That I agree with. Distortion rises very fast in the bass and lower mids when cranked to higher levels. This is measurable.

The box of my current speakers is tuned for 40hz extension (I've measured this flat except for a slight bass null at 50hz I need to address). But that's the thing with smaller speakers, usually they are not designed for maximum SPL. And any speaker can be driven to its maximum, it's simply a matter of at what level and how the speaker will react accordingly. Many drivers will start to compress and sound worse until they can't get any louder. Other drivers have a "hard limit" where it sounds fine until a particular point. It comes down to how you make decisions in the design.

But I'm not after very high SPL levels in my current living situation. I don't have the amp to get stupidly high either with inefficient speakers. And the drivers in my mini-monitors were not designed for high SPL but that decision allowed the designers to make performance advantages in other areas. Everything is a compromise. There is no perfect speaker. What I have now is akin to a mid-engined roadster that is sleek, sporty, quick, has razor sharp handling that's like driving on a knife's edge but it ain't expected to tow a boat or a family of 7.

Sure if I had the money, I'd get big woofers that give vanishingly low bass distortion, extension, efficiency, speed and tightness. That ain't gonna be cheap. But this notion you can't get quality bass from a small woofer is bullshit. Just like when I read you need bigger speakers for proper soundstage. Cabs ain't got nothing to do with soundstage.

 

He doesn't contradict anything I'm saying nor does he answer your second question. What's your point?

 

He builds for the parameters given by the marketing people. The market wants narrow baffles, so even KEF Blades had to have their 10" drivers on the sides (but Muons could have them in front). If audiophiles would spend the same amount of time looking for the right partner as they spend researching gear, there wouldn't be some silly WAF in play.

 

As I said, he builds to a specific price that puts constraints on the design. He's an excellent engineer who gets the most out of those limitations.

All I'm getting from folks here is the quality of bass is determined if it can dig deep and play loud. This is like an American muscle car vs European sports car argument. SBAFers like Camarro speakers. I prefer the finesse of a Lotus Elise.

A small speaker can do quality bass just as well if not better than a bigger one. Depends on your definition of "quality bass", as I said before. Nothing to do with WAF or marketing.

Disliked for being a smug asshole and insulting my audiophile friends who are considerate of their spouses.

 

European mains monitors for production of sophisticated European arts such as Eurodance for poor dancing and flailing of the limbs while under the influence of the ecstasy cut with the methamphetamine:




That's a 16" woofer. If your dick was that big, you could quit the job and pursue a novel career in pornography American as a big, bright shining star.

 

I need to get a pair of Orcas to match my penis size.

BTW those M3's are designed for higher SPL output. Just because they can get loud doesn't make them better than smaller woofers when it comes to bass quality.

 

All of those speakers are designed for the reference levels at the appropriate listening distance. Also, they can survive the volume for the rap, the metal, and the eurodance when checked by the artists.

 

Volume, Psalm, volume. If that's how you define good bass by how loud it gets, fine. I have a different definition.

 

Your definition is flaccid with chancres.

 

That would be my definition if all I listened to was Reign in Blood. More like eunuch bass.

 

Looks like I missed a whole 'multiple small woofers vs big woofer' discussion yesterday. However I still want to add some points:

"Moving mass is why smaller woofers sound faster."
This is something I find that's simply not true. Take four 8" woofers vs one 15" woofer for roughly the same 800cm² moving area. I think small woofers can just as easily be made to have the same low Fs (and really the large pro audio woofers normally have a higher Fs than the smaller "hifi" woofers), so they can usually be made to have very similar TS-parameters. So that's about as apples-to-apples as it gets.
However by moving four diaphragms for your 8" woofers your moving mass just quadrupled aswell. People seem to conveniently ignore that. Does it sound like slower bass now? No. I think the important spec here is not the moving mass itself, but rather the moving mass/surface area. And that's where some pro audio woofers (or vintage Altec drivers) with lightweight diaphragms excel. For a 15" woofer with 60g moving mass we would need just 15g moving mass for the 8" drivers. The only 8" drivers with less than 15g moving mass I know are widebanders like the Fostex FE206En/FE208EZ, Lowthers, etc. All of those are very Xmax-limited and will not be able to produce low distortion, high SPL low bass.
The moving mass/surface area is basically also what defines your overall efficiency. The reason why a single 15" woofer is often more efficient than four 8" woofers is because it has a lower moving mass. Use Tolvan Basta! to simulate a few drivers and you'll see what I mean. I made a small list of calculated values for moving mass/surface area some time ago: https://www.superbestaudiofriends.o...-and-recommendations.4062/page-47#post-236783

"The faster step response of a smaller woofer means it will sound faster even after low-pass filtering."
All it means is that the smaller woofer has more HF-extension. The reason why larger drivers don't reproduce high frequencies as well is due to cone breakup, size and VC Le. However once low pass filtered to the same response the step response will look the same. Due to beaming you may filter the larger woofer at a lower frequency, however for a true comparison you'd need to arrange the 8" woofers in a 2x2 grid, which will likely be even more beamy than the 15" woofer would be. Normally you would arrange them on top of eachother.
@RobS In your example of a "a whack from 0hz to 20hz" the rise time will be significantly slower than that of the 1kHz signal precisely because it is low-pass filtered. Your rise time will be on the order of 50ms.
Now that's not to say that I think subjective speed is nonsensical. I just don't think measured step response/impulse response/frequency response really correlates all that much to what I hear in terms of speed.

I've heard large woofers sound slow before and I've also heard multiple smaller woofers produce good quality bass before. What gives?
I think it has a lot to do with filtering and distortion. I haven't seen enough data to be sure, but HiFiCompass is an excellent starting point for distortion.* Compare the distortion across various driver sizes for the same voltage (if they're a similar impedance). For my example of 4x8" vs 1x15" woofers you would need to compare the distortion at a 6dB lower level for the 8" woofers vs the 15" woofers. Overall it seems that for bass distortion of the drivers they measured the 15" TD-15X Apollo and the 11" Accuton S280 woofers are the best so far. The 6.5" Purifi woofer also isn't too different at 2.83V vs the TD-15X at 5.6V (since it's a 4 Ohm vs 8 Ohm driver in that case). Keep in mind that you'd need about 13 of the Purifi woofers to replace two 15" woofers. In terms of price the choice is clear. However the smaller woofers aren't really made for larger speakers, anyway.
Generally suspension and motor linearity will be the most important here. This is also why low inductivity helps. Since Le is not constant across the range of motion of a driver (introducing harmonic distortion and FR changes across its excursion range) it's generally best to just keep it as low as possible. Otherwise there are ways to keep it as constant as possible.

My suspicion is that the filtering is perhaps the most important part why a smaller woofer would sound faster than a larger one. Especially when we compare 2 or 2.5-ways versus a 3-way speaker the additional crossover will introduce considerable group delay for the lower frequencies. My detailed subjective impressions on what the different crossovers do to the sound can be found here: https://www.superbestaudiofriends.o...over-phase-shift-audibility.9313/#post-301094
To be honest I think that's the main reason why a speaker with a larger woofer would produce "slower" sounding bass. Low distortion IMO helps with bass "quality" and to a certain extent can also influence speed, however I've heard some subwoofer designs which should have very low distortion and yet they sounded very slow and certainly "subwoofer-y" to me. Steep crossover filters at low frequencies will introduce a lot of group delay. Maybe that's another reason why some people are hesitant on getting larger speakers - they heard subwoofers and disliked the overall sound and falsely judged that to be due to the driver size. When people talk about group delay for different types of subwoofers (ported vs sealed) they never seem to take into account by how much the sub is delayed relative to the mains simply due to the necessary LP filter. That will often be far greater than the "delay" the port adds (which really isn't important when it's at a very low frequency.). You can easily experiment by generating filters in RePhase and applying it as a convolution to your music.

Overall I think it's more a matter of implementation. I've heard speakers with six highly expensive 8" woofers that sounded like they had "faster" bass than other speakers with one 15" woofer and I've also heard speakers with four 8" woofers that sounded "slower" than both. And then I've heard speakers with two cheap 15" woofers that put all of the above to shame with the fastest, most articulate bass I've heard so far. ;P

*Note that I feel it makes more sense to look at distortion relative to the harmonic frequency and not relative to the fundamental as plotted. This means drivers with steeper LF rolloff will appear as if they have more LF distortion than they do in reality. Really two different ways to look at the data, neither of them wrong.

 

Andrew is an excellent engineer. At the same time it's not the engineers who sell speakers. Sure there is a BOM cost limit, but there will always be limitations in terms of size and appearance dictated by marketing. The end product has to look in line with the brand book and it obviously has to look familiar enough to people. I've shown these monsters to top studio guys in LA:



Everyone was floored by the sound, but appearance was a very divisive factor. Many people would refuse to believe that these can do bass, because the box is open. Most people don't have the chance to audition speakers, so they have to sell by appearance and ideology alone. I do think Andrew's LS50 is a very good speaker, but a lion's share of its success it owes to small size and sharp looks. When you leave appearance to engineers you get stuff that looks like this -



And people see stuff before they hear it. And it's hard to unhear what you see.

 

Blast from the past. I'm fairly sure this is what my friend's dad had in his living room back in early 70s (???). A living room that was also used as a recording studio (partitioned off section with all the techie stuff including a disc-cutting lathe at the back. It was interviews, voice over, etc, so nothing like clear space for a band.). I still have the friend, but haven't been to the family house in decades. I know the other son has the refurbished Quad pre/power amps. Wonderful.

Apart from that, and four decades later, I got my head between big woofers that were part of a system that was all ex-cinema drivers. Even though it was in too small a room, I recall my review of that afternoon of listening to varied kinds of music: The most "being-there" system I ever heard. IIRC, that was powered by Quad too. The guy had read an article about low-power amp and high-efficiency speaker. I couldn't argue with the results.

The technicalities and measurements (whoa, I can just about understand inches) are way over my head, although I have struggled through most of this conversation. If one can call it that, but hey, I guess there's a lot good technical information fallout along the way.