Creating bass weight and impact?

[Bjorn]

Watch the first 30 seconds from where the video clip starts in post number 124, as it is relevant to my "more cost-effective" claim.

We agree on most, but I wanted to comment this. Multi subwoofers are not the most cost effective. The result I achieved below cost less than even two subwoofers. There's only front speakers used here.
Before and after frequency response overlay.

Before and after waterfall.

However, it required covering big surfaces and stole room area. So it's obviously not for everyone.

If we talk about the most cost effective solution and not the ideal solution, generally using EQ below 80 Hz and having one subwoofer to even out dips would be the better way to go. But it will never achieve the full potential and neither does multi subwoofers alone.

Another good compromise is combining physcial treatment above 80/100 Hz and apply some EQ to peaks below this. And use subwoofer(s) for that matter. It's a lot easier to treat the area above 100 Hz. Having the 100-250/300 Hz area with both short decay, resonance free and even makes a huge difference. We tend to focus too much on the deep bass and too little on the mid/upper bass and lower midrange IMO.

 

[Sokel]

Not advice you can take to the store and pick up a speaker, but here are some data points to consider. These three speakers each feature 15" woofers, horn loaded 4" diameter compression driver mids and horn loaded tweeters. Details and comments below.

View attachment 333820

The 4350 has (2) 15" woofers working in parallel up to 250Hz. A 12" midbass driver with the same motor as used on the 15" drivers that operates between 250Hz and 1200Hz. A 4" driver with aluminum diaphragm operating between 1200Hz and ~9500 Hz and an aluminum ring radiator and horn above.

The Speakers must be bi-amped at 250 Hz and has a sensitivity of 96dB/watt. These woofers roll off in most rooms below about 30Hz.

View attachment 333821

The DD67000 has (2) 15" woofers that operate in tandem up to about 150 Hz, only one woofer continues up to the 850 Hz crossover point to the 4" Beryllium domed compression driver which operates up to about 20kHz where the 1" Beryllium domed super tweeter kicks in.

The speaker is typically not bi-amped and has a 96dB/watt sensitivity. The woofers roll off in most rooms below about 40 Hz.

View attachment 333823

The last speaker is a DIY speaker that I built with a 15" woofer that is basically a sub and runs up to 75Hz where it crosses over to a 10" woofer that runs up to 750Hz to a 4" Beryllium compression driver that operates up to about 12kHz crossing over to a 1.5" Beryllium diaphragmed compression driver.

The speaker is tri-amped with a 93dB/watt sensitivity. The 15" woofer rolls off in most rooms below about 25Hz.

I mention the driver compliments and crossovers because these details help explain what driver(s) are the predominant players at various frequencies for these various systems. Above 1200 Hz all three speakers have similar horn loaded drivers. The DIY speaker with the TAD TH-4003/TD4003 combination sounds and measures the most linear, but for the purposes of this discussion all three are pretty much the same with ample headroom and very low distortion even at >110dB.

I have owned all three of these systems and set them up in multiple rooms. All three of these speakers are capable of exceeding safe listening levels by quite a margin and while I have blasted all three for brief periods above 105dB, I have never approached their calculated limits.

Regarding the focus of this thread, creating bass with weight and impact, the 4350 sounds the closest to a live performance... amplified large venue performance. If you are going for an unamplified string quartet it will be the least likely to convince you. But for the purpose of this thread, it has the ability to really playback music with impact and can fool you into thinking there is a maniac pounding the life out of a drum kit four feet away from you.

The DD67000 will do much better on the string quartet and will also get pretty darn close in the weight and impact department, but it actually needs a sub to pull it off as the VLF extension is simply not there and the lacking VLF becomes very apparent with some music.

The DIY system with the 10" woofer will do a more credible job on the string quartet than the other two, but it sounds more like your typical audiophile speaker in the weight and impact department. Think large Magico or Wilson. I am not saying that this DIY is as refined, depending on the model many of the larger Magico and Wilson speakers are really, really, great, but they still lack that last bit of impact. Just as this DIY speaker does.

My working assumption is that while the room does play a huge part in this, you need a fair amount of physical displacement, or a very large horn covering the range below ~800Hz. Think Magico Ultimate, not Klipsch. I have heard the Ultimates a couple of times in different rooms and have owned La Scalas and Klipschorns. These two designs from Klipsch will certainly get scary loud, but are not the last word in weight and impact.

It only makes sense the way you put it.
Strangely (as you talked about Wilson's) ,some hybrid watt-puppies (active at lows,passive for the rest) did a great job pounding a lot of slam in a medium size 50m² room once.

Every time I have asked old studio guys about "big" sound and impact the answer was "more than a 3" voice coil is a good start".

 

[Svend P]

The impact you are looking for is mostly dependent on the mid-bass, and air displacement by the woofer. The sound you are looking for can't be reproduced by small bookshelf speakers or small monitor no matter the quality of the speakers. The simple answer is you need big speakers even in a small room.

How would this show up in the measurements? I have tried with 6 pcs. 15" PA drivers going as high as 800 Hz, but they did nothing for the impact in my system

 

[Sokel]

How would this show up in the measurements? I have tried with 6 pcs. 15" PA drivers going as high as 800 Hz, but they did nothing for the impact in my system

Try only two of them,in stereo.right under your mains if they are separate and feed them some good amount of watts.

 

[Svend P]

Try only two of them,in stereo.right under your mains if they are separate and feed them some good amount of watts.

I have sold them off. I tried twice with different drivers, but there was nothing to gain. I could choose between a hooking sound or no effect.

But how would you measure impact?

 

[Sokel]

But how would you measure impact?

That's the big question.
It's a psychical property after all,there must be a way.

I already posted one way tested by Audioholics that seems legit:

Bass: the Physical Sensation of Sound

Ever wonder why you can feel bass? We take a look behind the science of bass waves and the tactile sensations that they cause. Our bass experiments were quite revealing but don't try them at home.

www.audioholics.com

Of course there must be more as some members above have stated.

 

[Duke]

We agree on most, but I wanted to comment this. Multi subwoofers are not the most cost effective. The result I achieved below cost less than even two subwoofers. There's only front speakers used here.
Before and after frequency response overlay.
View attachment 333866

Before and after waterfall.
View attachment 333867
View attachment 333868


However, it required covering big surfaces and stole room area. So it's obviously not for everyone.

If we talk about the most cost effective solution and not the ideal solution, generally using EQ below 80 Hz and having one subwoofer to even out dips would be the better way to go. But it will never achieve the full potential and neither does multi subwoofers alone.

Another good compromise is combining physcial treatment above 80/100 Hz and apply some EQ to peaks below this. And use subwoofer(s) for that matter. It's a lot easier to treat the area above 100 Hz. Having the 100-250/300 Hz area with both short decay, resonance free and even makes a huge difference. We tend to focus too much on the deep bass and too little on the mid/upper bass and lower midrange IMO.

WOW! What did you do to make such a dramatic difference?

 

[gnarly]

You said one must try to eliminate confounding variables while listening.

For sure... but I think we can also already expect that the vast majority of people who do not have a lot of practical experience with critical listening of bass frequencies or AB/ABX blind setup testing are going to have higher subjective tolerance for what is okay or acceptable.

Fully agree. I know I'm over the top re variable elimination.
I just wish more folks compared their indoor critical listening, to some outdoor critical listening.

The difference outdoors vs indoors, is so large that it it makes most all my critical listening comparisons indoors, feel like tweedily-dee-vs tweedily dum.

 

[NIN]

Fully agree. I know I'm over the top re variable elimination.
I just wish more folks compared their indoor critical listening, to some outdoor critical listening.

The difference outdoors vs indoors, is so large that it it makes most all my critical listening comparisons indoors, feel like tweedily-dee-vs tweedily dum.

Why should I listen ourdoors?

 

[gnarly]

Bingo! This is because the ear/brain system does not detect and classify the first arrival sound in the bass region quickly enough for us to perceptually differentiate it from the subsequent reflections! This IS a time-domain resolution issue!

Thanks Duke,

I really don't know what to think about how the ear/brain detects and perceives long wavelengths.
I haven't stubbled on any truly cogent and definitive science yet...as more researchers are beginning to say phase may be more audible at low frequencies than high.

And I think phase, not our ability to localize subs, or trying to discriminate how long it appears to take the ear/brain to recognize what frequency it's hearing.....
....I think phase is the key to how at a more full-spectrum integrated level, our hearing perceives a sense of correctness, a sense of reality, to sound.

Ok, so what does that have to do with multiple subs.....maybe nothing, maybe everything, dunno...

Back to multiple subs.
When I've smoothed out the frequency response (magnitude) in my rooms with multiple subs, a bit of work could get smoother response at listening position (and often other areas too).
Sustained bass tones were glorious. But even with pant-flapping power, ....unfortunately chest thump, strong bass transients like a kick drum, got weaker.
That was in a large well treated room where i could put multiple subs anywhere...even hung double 18"s from the ceiling, front and rear, trying stuff. Had a lot of subs to play with.

Here now in a smaller room but still fairly large (34x18x16 ft vaulted, and open into other rooms)...I'm constantly playing with 1, 2, or 3...or more subs.
Same phenom as before...sustained tones get stronger with more subbage, and response can be made smoother. But hit and slam diminish.

Best transient response, punch and slam, is almost always a single stack playing mono.... this keeps proving true for both indoors and out.
(Only exception is certain tracks have stereo L-R bass phasing that can sometimes reduce summed bass signal)

 

[Mr. Widget]

It only makes sense the way you put it.
Strangely (as you talked about Wilson's) ,some hybrid watt-puppies (active at lows,passive for the rest) did a great job pounding a lot of slam in a medium size 50m² room once.

Every time I have asked old studio guys about "big" sound and impact the answer was "more than a 3" voice coil is a good start".

I consider the Watt-Puppies as a smaller system, but the better ones, version 7 and later are quite good. While I haven't heard your bi-amped example, even the larger Wilsons I've heard are not monsters in the impact department... very, very good, but not monsters like those twin 15" JBLs.

Anecdotally, a buddy who has Watt-Puppies as his primary speakers borrowed a Meyer Sound system for a backyard party and was shocked by their capabilities. I am not suggesting that any PA system is better across the board, but for bass impact, most of the best consumer systems are just not designed with that as a focus.

 

[Duke]

When I've smoothed out the frequency response (magnitude) in my rooms with multiple subs, a bit of work could get smoother response at listening position (and often other areas too).
Sustained bass tones were glorious. But even with pant-flapping power, ....unfortunately chest thump, strong bass transients like a kick drum, got weaker.
That was in a large well treated room where i could put multiple subs anywhere...even hung double 18"s from the ceiling, front and rear, trying stuff. Had a lot of subs to play with.

Here now in a smaller room but still fairly large (34x18x16 ft vaulted, and open into other rooms)...I'm constantly playing with 1, 2, or 3...or more subs.
Same phenom as before...sustained tones get stronger with more subbage, and response can be made smoother. But hit and slam diminish.

Best transient response, punch and slam, is almost always a single stack playing mono.... this keeps proving true for both indoors and out.
(Only exception is certain tracks have stereo L-R bass phasing that can sometimes reduce summed bass signal)

Very interesting! I would call your room "quite large" for a home audio room, and it sounds like your previous room was even larger. I only have first-hand experience with one room in the size ballpark of your present room, and made no "before and after" comparisons in it.

In considerably smaller rooms I have yet to encounter a situation where a good distributed multi-sub system was a step backwards in "slam". Now the smaller the room the more it stands to benefit from the modal-region smoothing of a distributed multi-sub system, so presumably in a sufficiently large room other issues become dominant.

Outdoors the situation is completely different from the situation indoors in a small room, as far as speaker/room interaction goes in the bass region.

Are these large rooms of yours also open into other areas?

 

[Bridges]

I consider the Watt-Puppies as a smaller system, but the better ones, version 7 and later are quite good. While I haven't heard your bi-amped example, even the larger Wilsons I've heard are not monsters in the impact department... very, very good, but not monsters like those twin 15" JBLs.

Anecdotally, a buddy who has Watt-Puppies as his primary speakers borrowed a Meyer Sound system for a backyard party and was shocked by their capabilities. I am not suggesting that any PA system is better across the board, but for bass impact, most of the best consumer systems are just not designed with that as a focus.

I consider the Watt-Puppies as a smaller system, but the better ones, version 7 and later are quite good. While I haven't heard your bi-amped example, even the larger Wilsons I've heard are not monsters in the impact department... very, very good, but not monsters like those twin 15" JBLs.

Anecdotally, a buddy who has Watt-Puppies as his primary speakers borrowed a Meyer Sound system for a backyard party and was shocked by their capabilities. I am not suggesting that any PA system is better across the board, but for bass impact, most of the best consumer systems are just not designed with that as a focus.

I consider 100 square meters to be near PA system territory, even the large Wilson are barely adequate in that situation.

 

[gnarly]

Anecdotally, a buddy who has Watt-Puppies as his primary speakers borrowed a Meyer Sound system for a backyard party and was shocked by their capabilities. I am not suggesting that any PA system is better across the board, but for bass impact, most of the best consumer systems are just not designed with that as a focus.

My anecdotal add-on....
That exact same experience, when I took a pair of Meyer UPA-1Ps out for a backyard party 20 years ago.....has irrevocably changed my pursuit of best sound.

I don't remember if I had them on 650-P subs or if they were on some DIY Lab horns that Danley had designed for prosound web.
All I knew was that my days with home-audio gear had come to an end....
It would be one thing if just bass and its impact were better....but also hearing clarity beyond my electrostats ? From being outdoors????

(I'm not suggesting any particular brand either)

 

[srrxr71]

Why should I listen ourdoors?

Because room modes create cancellations in certain frequencies pretty much wherever you sit.

 

[gnarly]

n considerably smaller rooms I have yet to encounter a situation where a good distributed multi-sub system was a step backwards in "slam". Now the smaller the room the more it stands to benefit from the modal-region smoothing of a distributed multi-sub system, so presumably in a sufficiently large room other issues become dominant.

Outdoors the situation is completely different from the situation indoors in a small room, as far as speaker/room interaction goes.

Are these large rooms of yours also open into other areas?

What you say about smaller rooms makes sense to me; I can see the added benefit of modal suppression, at perhaps a cost of slam.


Yes, current room opens into a 20x11 dining and kitchen, and a hall foyer. Nothing grand, but added volume for sure.
Best part for bass, is I can sit in the main room with my back to a 6ft wide passthough bar type opening into kitchen, so that rear wall bounce is a 24 ft round trip.

 

[ooheadsoo]

I tried some horn speakers with 12" midbass woofers to chase after chest slam, but I really didn't get any improvement at all. I'm still at a loss on how to get gains in an ordinary multipurpose room.

 

[Bridges]

A more powerful might be helpful.

 

[Mr. Widget]

I tried some horn speakers with 12" midbass woofers to chase after chest slam, but I really didn't get any improvement at all. I'm still at a loss on how to get gains in an ordinary multipurpose room.

The speakers have to have the capability... just because they are large doesn't mean they are capable of providing bass with weight and impact.

As @Sokel said, "Every time I have asked old studio guys about "big" sound and impact the answer was "more than a 3" voice coil is a good start"." I think there is more to it than that, but this seems to be pointing in the right direction.

The venerable old Radio Shack party speaker, the Mach One has a 15" woofer, horn loaded HF section and will play loudly, but it won't fill a room with bass with weight and impact.

 

[Duke]

As @Sokel said, "Every time I have asked old studio guys about "big" sound and impact the answer was "more than a 3" voice coil is a good start"." I think there is more to it than that, but this seems to be pointing in the right direction.

Ime the correspondence is actually with motor strength, but that information is seldom made available. In general if a woofer manufacturer has gone to the trouble and expense of using a 4" voice coil they're not going to waste it on a weak motor, so "more than a 3" voice coil" is a good first approximation. But there are prosound woofers with 3" voice coils which have motor strengths competitive with good 4" voice coil woofers.

The venerable old Radio Shack party speaker, the Mach One has a 15" woofer, horn loaded HF section and will play loudly, but it won't fill a room with bass with weight and impact.

In order to get decent sealed-box bass from that size woofer in that size cabinet, the woofer must have a high Qes which in turn implies a low motor strength. And apparently such is indeed the case - here is the replacement woofer, which presumably is similar to the original:

https://www.parts-express.com/pedocs/specs/290-184--grs-rsrmo-8-spec-sheet.pdf

In order to do an apples-to-apples comparison of motor strength between woofers having different voice coil DC resistances (which translates into different BL figures even if the magnet strengths are actually identical), square the BL and divide it by the voice coil resistance. So it's Bl^2/Re. You can even take it one step further and divide that figure by the cone's moving mass (Mms) to get the power-to-weight ratio; or more precisely, the motor-strength-to-moving-mass ratio. The Mach 1 woofer is arguably abysmal by this metric.