Do high-efficiency speakers really have better 'dynamics'?

[tuga]

Regardless, if a resonating surface moves "faster", it will produce shorter wavelengths, aka higher frequency sound.

"Faster" drivers are audio snake oil.

You are missing the point; when people say “faster” they are referring to a perceived quality of the reproduced sound.

Could it have something to do with suspension-induces distortion? Something else?
I can conceive an advantage in terms of low-level detail reproduction by using lighter drivers but it’s an area of which I have not yet seen much research.

 

[Chromatischism]

I think of the idea "faster" or a (speaker + room) system's "speed" more to do with the transient response.

It may be relatively easy to tell between the ff. measurements as which bass managed system is going to be audibly "faster" :

Frequency dependent windowing (FDW) 15 cycles

View attachment 196610 View attachment 196611

View attachment 196612 View attachment 196613

View attachment 196614 View attachment 196615

View attachment 196616 View attachment 196617

It might be, but it's a wash in the end as the room will blur it all unless purpose-built or heavily treated.

 

[dlaloum]

In the bass, it depends on what you are trying to reproduce... many sound effects and synth effects are heavily artificial with no clear auditory reference to "real" sounds...

With acoustic instruments, sounds in the bass start out at around 35Hz to 40Hz - and they have complex harmonic structures....

Lots of subs don't do these instruments justice. Typically the best subs for this type of music, are sealed designs, where the inside air pressure supports the cone, and helps to push or pull it back into place... basically the sealed design to some degree counteracts the inertia of the cone - where on a ported sub, the "motor" has to move it, stop the motion, and bring it back.

Clearly the lower the inertia, the less effort required to move the air driver, stop it, and bring it back.

"Fast Speakers" - tend to be ones that do this well - they tend towards lower distortion as a result, and tend to be good at reproducing the complex low frequency sounds.

For cinematic effects, this is not a big deal, the priority is "pant flapping" and ground shaking effects - they are artificial in any case, and typically relatively harmonically simple - priority goes to SPL and getting max SPL's at very low frequencies (eg: 15Hz)

The other interesting thing, is that some of the very best subs, are multiple driver sealed arrays, using small drivers (eg 6" or even 4") - they tend to be able to achieve a combination of both "speed" and depth ...

I never found a sub that properly matched with my Electrostatic speakers (when I had them) - there was always a point where the behaviour of the two speakers disconnected... the subs felt "slow" - some people resolved this by developing monstrously huge electrostatic subs... - I never felt comfortable with Martin Logan electrostatics as a result - the bass never felt right - except for their CLS full range ESL.

There has been progress in subs though over the last 20 years....

How does one measure "Speed" of a driver - to my way of thinking, the ability to reproduce a low frequency square wave... and analysis of that square wave's shape - would provide some indication - typically to reproduce a square wave requires reproducing a series of harmonics at much higher frequencies which add up to the square wave... so to accurately portray a complex low frequency harmonic structure, the sub needs to be able to reproduce substantially higher frequencies.... does the tendency to cut over to subs and therefore frequency constrain them, affect their "speed"? and if so at what frequency should the XO be? and what slope would assist? - or perhaps (sacrilege?) proper complex low frequencies can only be reproduced by a full range speaker? (ie: are subs a flawed distraction from high fidelity?)

 

[nikosidis]

From my experience bigger bass drivers sound just as fast as small bass drivers and to me more like real bass.

I had some big subs that where slow but that has nothing to do with the size of the driver. It was underpowered.

A given amount of let's say 6" drivers will equal 15" but to me it does not.

Regarding horns I also feel there are something more real about them.

Recently I heard the JBL 4349 and also EROS-9 Anniversary.

EROS-9 ANNIVERSARY - Thivanlabs

thivanlabs.com

To me they sound very real.

Unfortunately I never had horn speakers but my next speakers must be horn loaded.

 

[dlaloum]

From my experience bigger bass drivers sound just as fast as small bass drivers and to me more like real bass.

So, what is your baseline .... what is "real bass" ?

To me, the sound of the bottom register of a double bass played unamplified, or a Tuba, defines "real bass"

What is your criterion for "reality"?

 

[freemansteve]

I suspect natural instruments, normally and ideally heard unamplified, may be harder to reproduce in a way that sounds as if they are there in your room.

For electric instruments, and for synthed sounds, defining reality is pretty hard. The the best you might achieve, especially for rock etc, is for you to feel you are at a gig where (unusually) the sound guy has got it right, or as if you are the studio with the band playing for the recording. In both cases, you will get the dynamic "feeling" possibly because it can get loud and feel pretty "full range".

Sadly, it seems likely that far to few people who are into HiFi regularly go to gigs/concerts or play instruments themselves (not digging at anyone - but it kinda puts "reality" in context).

 

[dlaloum]

I suspect natural instruments, normally and ideally heard unamplified, may be harder to reproduce in a way that sounds as if they are there in your room.

For electric instruments, and for synthed sounds, defining reality is pretty hard. The the best you might achieve, especially for rock etc, is for you to feel you are at a gig where (unusually) the sound guy has got it right, or as if you are the studio with the band playing for the recording. In both cases, you will get the dynamic "feeling" possibly because it can get loud and feel pretty "full range".

Sadly, it seems likely that far to few people who are into HiFi regularly go to gigs/concerts or play instruments themselves (not digging at anyone - but it kinda puts "reality" in context).

On rare occasions, I have had classical musicians hear music on my setup, their ( invariably surprised ) response, is that " it sounds real".

All of them listen to music, but few of them have heard what " hifi" can do.

To make a violin, an acoustic guitar, or a saxophone, sound real, is my definition of high fidelity.

( and yeah, we are also shackled to the quality of the recording )

 

[freemansteve]

Indeed - my niece spent years playing in orchestras, and she was startled by a rig I used to have, but then her experience to date was only one of "live" or add-on PC speakers..... The low level of background noise was a surprise to her (studio recordings on my rig, versus live, where people shuffle about, turn pages, cough, and then the aircon turns on!)

 

[gnarly]

As many have said, the idea of of driver 'speed' is a huge set of misconceptions, imnsho.

The audible quality often described as speed, is best described as transient response.
And transient response is a function of full-range frequency response. (phase too, if cutting edge)

A subwoofer driver has very little discernable transient response on its own, it must be combined with the rest of the spectrum before its transient response can be evaluated.

Listen to your sub alone, particularly with its low pass filter in place if it is being crossed over to main speakers.
Download and play the ultimate transient impulse, a single sample full spectrum Dirac pulse https://www.audiocheck.net/testtones_impulse.php
Not much to hear, huh?....
(make sure it is sub alone, or volume is low for full speaker...lots of HF energy.)

Ironically, the subs with the highest amount of THD will sound like they have greater transient response...
simply because transient response (repeat after me Lol) is a function or frequency response.

The mass of the driver's diaphragm, cone, ribbon, etc, has to be considered in combination with the strength of the motor driving it.
Alone, mass is immaterial. Power to weight rules.

Better subs do not strictly attempt to lower cone & coil mass....they optimize those materials with the motor strength for the intended SPL and low frequency extension..

Best 'speed'..... best transient response possible, ........comes from a complete full-range response, having both flat magnitude (freq response) and flat phase, where all contributing drivers are operating in their pistonic range. (no breakups producing higher freq response)

Sure a room can muck things up, but any speaker that meets the above 'best transient response possible criteria' will sound "fastest haha" and better in any room, than a speaker that doesn't meet it. (all extraneous variables being the same, e.g. radiation patterns, linear SPL capability, etc)

 

[tuga]

It might be, but it's a wash in the end as the room will blur it all unless purpose-built or heavily treated.

Yep, just get headphones and bidun.

 

[Chromatischism]

Lots of subs don't do these instruments justice. Typically the best subs for this type of music, are sealed designs, where the inside air pressure supports the cone, and helps to push or pull it back into place... basically the sealed design to some degree counteracts the inertia of the cone - where on a ported sub, the "motor" has to move it, stop the motion, and bring it back. Clearly the lower the inertia, the less effort required to move the air driver, stop it, and bring it back.

Vented subs do the same above the tuning frequency. A vented sub tuned really low is essentially a large sealed sub above about 35 Hz and is why they sound the same in that range if all else is equal.

The driver is under control at all times until below the tuning frequency of the vents, which on the better subs isn't until the infrasonics.

 

[Chromatischism]

How does one measure "Speed" of a driver - to my way of thinking, the ability to reproduce a low frequency square wave... and analysis of that square wave's shape - would provide some indication - typically to reproduce a square wave requires reproducing a series of harmonics at much higher frequencies which add up to the square wave... so to accurately portray a complex low frequency harmonic structure, the sub needs to be able to reproduce substantially higher frequencies.... does the tendency to cut over to subs and therefore frequency constrain them, affect their "speed"? and if so at what frequency should the XO be? and what slope would assist? - or perhaps (sacrilege?) proper complex low frequencies can only be reproduced by a full range speaker? (ie: are subs a flawed distraction from high fidelity?)

It's hard to make heads or tails of this stream of consciousness but it is widely known that the best blend between subwoofer and speaker in a typical home system and room is a crossover of between 70-90 Hz, often times using an LR4. Any higher and you get a degradation of sound quality in one form or another.

Subs will always outperform full range speakers when done right.

And there is no need for complex multiple small driver subs. You just need a smooth in-room bass response and a good blend. Your issue was likely that your ESLs simply can't go low enough to blend well with subs so the "something in the middle" was missing.

 

[Chromatischism]

As many have said, the idea of of driver 'speed' is a huge set of misconceptions, imnsho.

The audible quality often described as speed, is best described as transient response.
And transient response is a function of full-range frequency response. (phase too, if cutting edge)

A subwoofer driver has very little discernable transient response on its own, it must be combined with the rest of the spectrum before its transient response can be evaluated.

Listen to your sub alone, particularly with its low pass filter in place if it is being crossed over to main speakers.
Download and play the ultimate transient impulse, a single sample full spectrum Dirac pulse https://www.audiocheck.net/testtones_impulse.php
Not much to hear, huh?....
(make sure it is sub alone, or volume is low for full speaker...lots of HF energy.)

Ironically, the subs with the highest amount of THD will sound like they have greater transient response...
simply because transient response (repeat after me Lol) is a function or frequency response.

The mass of the driver's diaphragm, cone, ribbon, etc, has to be considered in combination with the strength of the motor driving it.
Alone, mass is immaterial. Power to weight rules.

Better subs do not strictly attempt to lower cone & coil mass....they optimize those materials with the motor strength for the intended SPL and low frequency extension..

Best 'speed'..... best transient response possible, ........comes from a complete full-range response, having both flat magnitude (freq response) and flat phase, where all contributing drivers are operating in their pistonic range. (no breakups producing higher freq response)

Sure a room can muck things up, but any speaker that meets the above 'best transient response possible criteria' will sound "fastest haha" and better in any room, than a speaker that doesn't meet it. (all extraneous variables being the same, e.g. radiation patterns, linear SPL capability, etc)

I agree. When you achieve flat and smooth bass response, so that no masking is occurring, bass detail and "speed" will increase - a lot.

But there is another factor. Small subs (and speakers) don't produce the lowest bass. This naturally causes them to sound "faster". It's simply how our perception of very low frequencies (or lack of) works.

 

[nikosidis]

So, what is your baseline .... what is "real bass" ?

To me, the sound of the bottom register of a double bass played unamplified, or a Tuba, defines "real bass"

What is your criterion for "reality"?

Well, I'm first thinking about the dynamics and density from electric bass guitar. That is kind of my reference since I been playing in a rock band for a long time. I would kind of apply the feeling to what a horn tweeter do. To me that also sound more realistic. It is never a question if you hear instruments for real or from a Hi-Fi. It is never the same and much of the limitation is stereo but it is also density I think. Maybe I'm way off but seams like horn tweeters and big bass drivers are faster or got a lot more headroom.

 

[Duke]

I never found a sub that properly matched with my Electrostatic speakers (when I had them) - there was always a point where the behaviour of the two speakers disconnected... the subs felt "slow" - some people resolved this by developing monstrously huge electrostatic subs... - I never felt comfortable with Martin Logan electrostatics as a result - the bass never felt right - except for their CLS full range ESL.

The perception of "speed" in the bass region is predicted by the in-room frequency response curve. At bass frequencies, speaker(s) + room = a "minimum phase" system, meaning that the time-domain response tracks the frequency response. So a peak in the frequency response in the bass region corresponds with longer time for that energy to decay into inaudibility. The good news is, when you fix one you have simultaneously fixed the other. This is why EQ and/or a distributed multisub system (both of which directly addresses the frequency response) correspondingly improve the time-domain response, and why increasing the in-room acoustic damping (which directly addresses the decay times) correspondingly improves the in-room frequency response.

As a general principle, the greater the number of widely-separated bass sources in a room, the smoother the in-room frequency response and therefore the "faster" the bass is perceived to be. You can think of a dipole as two monopoles, back-to-back, separated by 180 degrees of phase differential and by the wrap-around path length. So two dipole main speakers approximate the in-room bass smoothness of four intelligently-distributed monopole speakers, implication being that it would take four subwoofers (intelligently distributed) to approximate the in-room bass smoothness of two dipole main speakers. This might be part of the explanation for the audible discontinuity between panels and woofers that you heard with hybrid electrostatic speakers.

How does one measure "Speed" of a driver - to my way of thinking, the ability to reproduce a low frequency square wave... and analysis of that square wave's shape - would provide some indication - typically to reproduce a square wave requires reproducing a series of harmonics at much higher frequencies which add up to the square wave... so to accurately portray a complex low frequency harmonic structure, the sub needs to be able to reproduce substantially higher frequencies.... does the tendency to cut over to subs and therefore frequency constrain them, affect their "speed"? and if so at what frequency should the XO be? and what slope would assist? - or perhaps (sacrilege?) proper complex low frequencies can only be reproduced by a full range speaker? (ie: are subs a flawed distraction from high fidelity?)

In the bass region room interaction effects (in both the frequency and time domains) are roughly an order of magnitude greater than the difference between two well-designed subwoofers. So the implication is that effectively addressing room interaction pays significantly greater dividends than does making incremental improvements in subwoofer quality. Note that, perceptually, there is no such thing as "first arrival sound" in the bass region. This is because the ear cannot begin to detect the presence of bass energy from less than one wavelength, and must hear multiple wavelengths to begin to detect the pitch of a bass tone. Consider how long bass wavelengths are and how short the reflection paths in the room are: By the time we begin to hear the bass, room effects are already dominant. Yes we can hear a qualitative difference between subs (the ear is actually very sensitive to small SPL differences in the bass region), but we hear much more of a qualitative difference between smooth in-room bass and lumpy in-room bass.

 

[Newman]

think of a dipole as two monopoles, back-to-back, separated by 180 degrees of phase differential and by the wrap-around path length. So two dipole main speakers approximate the in-room bass smoothness of four intelligently-distributed monopole speakers, ….it would take four subwoofers (intelligently distributed) to approximate the in-room bass smoothness of two dipole main speakers.

That’s not right. Taking 4 monopole subwoofers and placing them as 2 back-to-back pairs, with one of each pair out of phase with the other, is more like the opposite of “intelligently distributing” them.

 

[Duke]

That’s not right. Taking 4 monopole subwoofers and placing them as 2 back-to-back pairs, with one of each pair out of phase with the other, is more like the opposite of “intelligently distributing” them.

I'm not advocating placing two subs back-to-back to create a dipole, and my apologies if that's how it came across. In order for that configuation to work we'd need considerable EQ to offset the cancellation, and there would still be issues which I won't go into here.

James M. Kates wrote a paper many years ago (which I don't have the reference for) which shows the improved in-room bass smoothness of a dipole relative to a monopole. So if we want to approximate the in-room bass smoothness of a dipole, we need to make a worthwhile improvement over the in-room bass smoothness of a monopole.

And an intelligently-distributed multi-sub system (consisting of monopole subwoofers) is an acoustic solution to that problem.

 

[Duke]

Vented subs do the same above the tuning frequency. A vented sub tuned really low is essentially a large sealed sub above about 35 Hz and is why they sound the same in that range if all else is equal.

Yes!

Imo a vented topology has this advantage: It is possible to juggle woofer parameters, box size, and tuning frequency such that the frequency response approximates the inverse of room gain (from boundary reinforcement) over a range of about two octaves. With a sealed sub, an inverse-of-room-gain response over a substantial frequency range is impractical without EQ. Not that EQ is a bad thing, but it can be an expensive thing in terms of amplifier power requirements and woofer power-handling requirements.

 

[Newman]

I'm not advocating placing two subs back-to-back to create a dipole, and my apologies if that's how it came across. In order for that configuation to work we'd need considerable EQ to offset the cancellation, and there would still be issues which I won't go into here.

James M. Kates wrote a paper many years ago (which I don't have the reference for) which shows the improved in-room bass smoothness of a dipole relative to a monopole. So if we want to approximate the in-room bass smoothness of a dipole, we need to make a worthwhile improvement over the in-room bass smoothness of a monopole.

And an intelligently-distributed multi-sub system (consisting of monopole subwoofers) is an acoustic solution to that problem.

IMO you have made some conceptual leaps that are not valid. IIRC Kates’ paper used 2D modeling, which omitted vertical modes with monopoles, and that made them look lumpier than they really are (Kates assumed dipole bass is line-source-like and has no vertical modes), and the paper attracted criticism for that.

Also, why jump to 4 monopole subs? Just because 4 monopole subs in bad locations and phase and positioning will look like a dipole bass pair? Toole showed how much smoother the bass can be with 2 well-placed subs than with one, and until shown otherwise I’ll suggest that it will be smoother than the bass from 4 monopole subs, placed where the main speakers go, back to back and out of phase and with a path-length-delay simulation….ie dipole bass.

Let’s face it: the real reason people have had trouble over the decades getting monopole bass units to sound good* with dipole mains, is that they didn’t know what they were doing in the bass regions.

*assuming the usual confirmation bias effects have been controlled for, otherwise dipole-with-dipole will always “sound better” because they think it should.

 

[Newman]

Not that EQ is a bad thing, but it can be an expensive thing in terms of amplifier power requirements and woofer power-handling requirements.

It shouldn’t be, in a home ie small room scenario. Unless you are using dipole bass, heh. Remember that bass EQ should do very little boosting, instead, mainly cuttiing the heads off of resonant peaks. Which doesn’t require more power.