posted
If someone has the free time can they explain all the T/S Paremeters and what they mean like Vas, QTS....and the rest of them.I think I know what most of them mean but I want to make sure . Thanks Ryan
-------------------- Only one way to know if it works.....try it. Posts: 193 | From: Sour Lake TX | Registered: Dec 2002
| IP: Logged |
posted
The first thing to know about T/S parameters is that they model the speaker as a 2nd order simple oscillator (ie a weight suspended by a spring). If you took physics you should be familiar with that concept. Now, with that in mind.
Fs - The resonant frequency of the speaker mass-spring system. This is the frequency that the cone vibrates most freely at.
Qts - The 'Q' of the speaker's resonance. This is a measure of how quickly the resonance loses energy. Lower values indicate a rapid loss of energy. It is made up of Qes in parallel with Qms.
Qes - The component of Qts resulting from the motor system of the speaker. "electrical Q"
Qms - The component of Qts resulting from the suspension of the speaker. "mechanical Q"
Vas - The volume of air equivalent to the 'K' factor of the spring in the mass-spring model. This is a measure of stiffness put in a form that makes the enclosure design calculations come out nicer.
Those are the basic T/S parameters that define the 2nd order model. Here are some more that are commonly refered to as T/S parameters.
BL - The electromagnetic force factor of the motor. Expressed as Newtons per Ampere or Tesla * Meters they are dimensionally identical. This is the factor that when multiplied by the current through the voice-coil will give the force exerted by the coil on the cone. The value is given as a single number (the value with the cone at rest) but it changes as the cone moves in and out.
Mms - The moving mass of the speaker. This includes the mass of the cone, coil, and part of the suspension as well as the air mass load. This is the mass of the air right next to the cone that moves as though it were attached to the cone.
Re - The DC resistence of the voice coil. Or the real part of the speaker's impedence depending on the model being used. The first is constant the second is frequency dependent.
Le - The inductance of the voice coil. This is a frequency dependent parameter, unlike the inductance of an inductor.
posted
Those are all small signal parameters, which is what T/S specs describe. Xmax, Pe, and even Vas are large signal and therefore not technically considered t/s specs.
Posts: 768 | From: Ottawa, On, Canada | Registered: May 2000
| IP: Logged |
quote:Originally posted by emu: Those are all small signal parameters, which is what T/S specs describe. Xmax, Pe, and even Vas are large signal and therefore not technically considered t/s specs.
well if you put it that way, then Fs, Qts, BL, and most all other parameters become dynamic (large-signal dependent) with excursion and power, unless you have a flat BL & Kms, along with ultra-low power compression
-------------------- SD.com sucks, thats why im here.
show respect to the dead: RIP solobaricsrock 600 posts RIP solobaricsrock2 4600 posts solobaricsrock3 is still alive, but walking a thin line:) Posts: 1 | From: here n' there | Registered: May 2003
| IP: Logged |
Printer-friendly view of this topic