What's the best/ optimal bass driver size ?

[DVDdoug]

Why the sarcasm

It's just a way of saying that there's no single-simple answer, or maybe no answer at all...

"Who is John Gault?"

 

[Pearljam5000]

It's just a way of saying that there's no single-simple answer, or maybe no answer at all...

"Who is John Gault?"

Oh OK
I got to work on my English then
I didn't know that.

 

[dfuller]

Why the sarcasm

There's no sarcasm here. There's no one best answer here.

 

[fpitas]

The one I use is the best.

/There, that was easy.

 

[sarumbear]

There are a lot of exceptions but they tend to be expensive, like the JBL 2216ND which is run all the way up to the tweeter in the JBL M2. It's also $435.

Mind you that is not an ordinary “Twitter”. It works above 800Hz!

 

[fpitas]

I don't think there exists an answer for this.

Not without a lot of qualifications.

 

[kemmler3D]

Mind you that is not an ordinary “Twitter”. It works above 800Hz!

Also a good point. The M2 is a pretty interesting speaker because that's a very low xover for a tweeter, very high xover for a 15", and somehow they made it sound good anyway.

 

[nerdoldnerdith]

Yes obviously bigger driver = more bass
But what's the optimal size for clean and tight bass in either a speaker or a sub ?
And Also is it better to have 1X15 inch driver or 2X8 inch instead etc ?

The bigger the better. 15" for a speaker. 21" for a sub.

The less a driver has to move the lower distortion it will have. Larger drivers also tend to have lower group delay and a lower Fs in the appropriate enclosure.

The idea that smaller drivers are faster is a myth that comes from the fact that they tend to roll off higher, which tends to produce a flatter bass response which sounds less boomy without EQ. When EQ is used, the flat and extended bass you get from larger drivers will sound better.

 

[nerdoldnerdith]

A loudspeaker in a room is a minimum phase system. Assuming the speaker behaves linearly, the time domain response you get in your room will be determined by frequency response. The way you get the best bass is by using multiple subwoofers and DSP to get a frequency response as flat as possible with as few nulls as possible.

 

[Chrispy]

On the subject of calculating surface area of the driver, hould Sd be based on simple area calculations (as if a simple/flat circle) or cone surface area calculations?

 

[nerdoldnerdith]

On the subject of calculating surface area of the driver, hould Sd be based on simple area calculations (as if a simple/flat circle) or cone surface area calculations?

Using Klippel to get parameters will give you an exact number. It's usually pretty close to the area of a circle with radius going from the center of the driver to the center of the surround.

 

[howard416]

Disregard size/power/excursion/every other single point of reference and go based on calculated air moved or better yet, measurements.

There are some 12" and 15" drivers that are utter garbage compared to a dual 4" on a Devialet Phantom Reactor.

Sure, there are some bad 12" and 15" drivers, but which of them are worse than a high-end dual 4" setup? Even a single bargain-bin 12" would likely outperform a pair of Purifi 4" mids (in the bass region only), let alone some 4" drivers from a little-known manufacturer?

 

[BrokenEnglishGuy]

Sure, there are some bad 12" and 15" drivers, but which of them are worse than a high-end dual 4" setup? Even a single bargain-bin 12" would likely outperform a pair of Purifi 4" mids (in the bass region only), let alone some 4" drivers from a little-known manufacturer?

The thing is, the Deviant phantom are very special.. xD
I don't know why these guys doesnt make a coaxial for the front, that would resolve a lot of their problems

 

[Chrispy]

The thing is, the Deviant phantom are very special.. xD
I don't know why these guys doesnt make a coaxial for the front, that would resolve a lot of their problems

If they are called "Deviant" you'd hope they would at least be different, special maybe. Deviant usually just means an abnormal shift from normal, tho. Devialet not sure where they fit in particularly, they seem to employ a fair bit of bullshit.

 

[howard416]

On the subject of calculating surface area of the driver, hould Sd be based on simple area calculations (as if a simple/flat circle) or cone surface area calculations?

Circle. Some people say to include half of the surround, some say the inside 30% (or third). Not that it makes any appreciable difference, unless your surround is very wide compared to the "rigid" part.

 

[Chrispy]

Circle. Some people say to include half of the surround, some say the inside 30% (or third). Not that it makes any appreciable difference, unless your surround is very wide compared to the "rigid" part.

Just wondering if measuring to surround (or mounting bolt circle) somehow generally alleviated differences between diameter/radius calc vs cone area calc. Just couldn't find in a brief search what the original calculations were specified for....

ps plus wonder if that's the "official" way...as have seen those saying it should be proper cone area.

 

[JohnBooty]

Disregard size/power/excursion/every other single point of reference and go based on calculated air moved or better yet, measurements.

There are some 12" and 15" drivers that are utter garbage compared to a dual 4" on a Devialet Phantom Reactor.

Similarly, in a small room at around 7feet/2.13m listening distance, the Tang Band W4-1720 can actually produce palpable bass. I was feeling it in my chest. Thought that was very impressive.

 

[Chrispy]

Similarly, in a small room at around 7feet/2.13m listening distance, the Tang Band W4-1720 can actually produce palpable bass. I was feeling it in my chest. Thought that was very impressive.

So what particular frequency range do you think that was?

 

[howard416]

Just wondering if measuring to surround (or mounting bolt circle) somehow generally alleviated differences between diameter/radius calc vs cone area calc. Just couldn't find in a brief search what the original calculations were specified for....

ps plus wonder if that's the "official" way...as have seen those saying it should be proper cone area.

There's a lot of math that I forget that relates volume displacement, velocity, and acceleration of a cone to the SPL produced. Suffice it to say that the acceleration makes the sound and the acceleration has a direction. A deeper or shallower cone (unless, perhaps, you push it to ridiculous proportions) doesn't change how much sound is made. Don't calculate based on surface area of a cone.

 

[sigbergaudio]

The bigger the better. 15" for a speaker. 21" for a sub.

The less a driver has to move the lower distortion it will have. Larger drivers also tend to have lower group delay and a lower Fs in the appropriate enclosure.

The idea that smaller drivers are faster is a myth that comes from the fact that they tend to roll off higher, which tends to produce a flatter bass response which sounds less boomy without EQ. When EQ is used, the flat and extended bass you get from larger drivers will sound better.

But increasing the number of drivers can result in smaller drivers moving less as well, so it's about total surface area and staying within linear excursion more than the size of each individual driver. You can also find smaller (8-10") drivers with low Fs. Lower group delay in larger drivers sounds made up.

So neither "smaller drivers are faster" or "larger drivers are better" is categorically true.