Sorry for my english! Some experts needed. With white beard and big glasses!
The first question.
Is the higher Bl really tells us the driver have more acceleration, control, more articulate sound?
If two drivers have the same Qts 0.35, Qes 0.35, same FS but difference is in BL and QMS.
High BL like 8 and hard qms like 1.5-2 or something like this...
VS
Not so high Bl like 5.5 and easier qms like 5-6 or something like this...
Is BL force factor have some formulas with qes or this is very different parameters? How to understand whitch driver is better, articulate, faster, have more resolution? The fs and qms tells us different bass reproduction or its not? I am from this guys why likes fast with big weight in bass, articulate, punchy sound with 3d effect and resolution. Usually i don't think someone prefer different type of sound.
If compare drivers like this for example.
CA18RNX
SB17NAC
Is it big difference in sound?😕
What parameters you look first of all?
Second question.
Someone compares LR2 vs LR4 vs first order? What is pleasant to you more?
If we got the target with the acoustic order as planned.
I saw something like this too. LR2 and acoustic first order.
Sorry guys for this type of conversation. 😀
The first question.
Is the higher Bl really tells us the driver have more acceleration, control, more articulate sound?
If two drivers have the same Qts 0.35, Qes 0.35, same FS but difference is in BL and QMS.
High BL like 8 and hard qms like 1.5-2 or something like this...
VS
Not so high Bl like 5.5 and easier qms like 5-6 or something like this...
Is BL force factor have some formulas with qes or this is very different parameters? How to understand whitch driver is better, articulate, faster, have more resolution? The fs and qms tells us different bass reproduction or its not? I am from this guys why likes fast with big weight in bass, articulate, punchy sound with 3d effect and resolution. Usually i don't think someone prefer different type of sound.
If compare drivers like this for example.
CA18RNX
SB17NAC
Is it big difference in sound?😕
What parameters you look first of all?
Second question.
Someone compares LR2 vs LR4 vs first order? What is pleasant to you more?
If we got the target with the acoustic order as planned.
I saw something like this too. LR2 and acoustic first order.
Sorry guys for this type of conversation. 😀
Seas have Rms 1,72 and Le 1,2
VS
Sb acoustic Rms only 0,5(less loss more articulate sound?) and Le only 0,13(less inductance better midrange?)
Looks like SB better but only one thing is BL???
VS
Sb acoustic Rms only 0,5(less loss more articulate sound?) and Le only 0,13(less inductance better midrange?)
Looks like SB better but only one thing is BL???
rough guide
higher qms = more dynamic sound.
low le = less distortion, better articulation, better high end extension.
Of course a speaker is always a complete package, so...
ymmv.
higher qms = more dynamic sound.
low le = less distortion, better articulation, better high end extension.
Of course a speaker is always a complete package, so...
ymmv.
Thank you! "more dynamic sound" is it for midrange and for bass too?
Some people understands dynamic sound like fast midrage not puncy artikulate bass with weight.
Some people understands dynamic sound like fast midrage not puncy artikulate bass with weight.
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Thiele small parameters do not tell you how a speaker will sound outside the bass region response shape. The question is fundamentally flawed and a waste of everyone's time.
Qms is defined strictly at resonance. It does not necessarily have anything to do with sound anywhere else. There are reasons a speaker has a low Qms (conductive former) that have nothing to do with lossy surrounds that some people love to hate on.
Qms is defined strictly at resonance. It does not necessarily have anything to do with sound anywhere else. There are reasons a speaker has a low Qms (conductive former) that have nothing to do with lossy surrounds that some people love to hate on.
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Thanks! This is the problem. Higher BL means more damping. Lover qms. Not so high BL and looks like Qms bigger, less damping. The Qes is the same... is it reali don't matter? May be some one have some experience head to head comparison with this situation? The difference not so big and not worth it?
Go here and look at the formulas. Bl has nothing to do with Qms so your question makes no sense.
Thiele/Small parameters - Wikipedia
The only thing that really matters for amplitude response shape is Qts, which represents total damping at resonance. The relative proportions of electrical and mechanical damping don't matter.
A higher Qms driver will have a higher impedance peak, which can actually be a problem in some circumstances.
I suggest you read a bit more about the topic and formulate some more answerable questions later.
Thiele/Small parameters - Wikipedia
The only thing that really matters for amplitude response shape is Qts, which represents total damping at resonance. The relative proportions of electrical and mechanical damping don't matter.
A higher Qms driver will have a higher impedance peak, which can actually be a problem in some circumstances.
I suggest you read a bit more about the topic and formulate some more answerable questions later.
Thank you for this formula! A got good results!
CA18RNX fom spec. Bl 7,2
Formula 7,13
SB17NAC35-4 fom spec. Bl 5,2
Formula 5,2
CA15RLY fom spec. Bl 5,5
Formula 5,3
I Am shocked about Cms! The smaller Cms, the harder suspension -> Bl bigger! More damping more control? but this means not so forceful and dynamic?😕
Resistance of coil interesting too...BIGGER resistance better. But how they know how good amplifier is? This is with 1a currrent? 😕
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BL is the product of the magnet field strength against the length of wire in the magnetic gap.
BL and Qes are inversely proportional. High BL is low Qes and vice versa. My way of thinking is that low Qes is a very powerful magnet. High Qes is a weak magnet. One of Speaker Builder Magazine's contributors used to say "The right amount of magnet is always the right amount of magnet". I like that proverb very much.
Cms and Vas are inversely proportional. Low Cms is high Vas and vice versa.
Cms is physically the springyness of the spider and surround lumped together.
The mass of the moving speaker guts is Mms.
Fs = 1/sqrt(Cms * Mms)
...and so on....
This is all from memory. If I made mistakes, apologies...
BL and Qes are inversely proportional. High BL is low Qes and vice versa. My way of thinking is that low Qes is a very powerful magnet. High Qes is a weak magnet. One of Speaker Builder Magazine's contributors used to say "The right amount of magnet is always the right amount of magnet". I like that proverb very much.
Cms and Vas are inversely proportional. Low Cms is high Vas and vice versa.
Cms is physically the springyness of the spider and surround lumped together.
The mass of the moving speaker guts is Mms.
Fs = 1/sqrt(Cms * Mms)
...and so on....
This is all from memory. If I made mistakes, apologies...
It is truly a waste of time to listen to many people especially those not understanding this bunch of numbers called TSP. The benefit of these is to get a picture what you can expect of a certain driver, how loud, how deep, and what kind of loading and enclosure size it may be needed to work normally, the way you want it to. What it will sound like is not to be deduced from TSP. You will have to build it and listen in your own environment. And by then you will have introduced a lot more variables in a formula that together make the final result.
Btw, the photograph you posted is as unique and as interesting as not so often to be seen in general, imo.
"B" is the intensity of magnetic flux in the gap (that the wire of the voice coil is exposed to) and "L" is nothing more than the total length of wire in the voice coil (that is in the gap). Thus, B * L, or "BL product".
That's what BL is in physical terms. In functional terms, it shows the closeness of magnetic coupling between the motor system and the amplifier. On one end of the spectrum, there are magnetic-planar loudspeakers with very low BL factors as a result of weak B fields. This results in nearly resistive impedance curves. Easy to drive, but also very inefficient. Raising the BL factor requires the pairs of magnets get closer together, but that limits diaphragm excursion, and also requires a much stronger frame for the magnet pairs.
On the other end of the spectrum, there are compression drivers with very high BL products. The gap is very narrow, and the magnets are remarkably large. The strength of the magnetic field in the gap is very high, and efficiency is high also.
Conventional direct-radiator drivers fall midway between these extremes of BL product. Manufacturers select magnet size (and the length of wire in the gap) so the bass or midbass driver has a useful set of T/S parameters for cabinets with acceptable sizes. In the time before T/S theory was in use (first publication in the AES Journal was 1973 or so), driver manufacturers chased efficiency, so drivers were made that had very high BL products and low Qes parameters. BL product was a spec back then, but there wasn't much understanding of what we'd call Qes today.
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