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This is not actually what I said
kasey wrote: I see you said that a 4 ohm sub will perform different than a 8 ohm. How is this possible?
I understand what you are saying now, and I definitely learnt something, but in terms of power, you're saying a 4 ohm version sub rated 1200watts will sound different as compared to the same model 8 ohm version sub rated 1200watts if they are tested in the same enclosure? I mean if two different 1200watt amplifiers are used for each sub (a 1200watt 8ohm amplifier, and a 1200watt 4ohm amplifier). I honestly thought that if you give a speaker its rated power, it will sound the same regardless of its impedance (because you match its impedance to the amplifiers power rating).
Cubo15 wrote: Personally I've never seen an 8 and 4 Ohm version with the exact same T/S-parameters.
The 4 Ohm version will see 1.414 times as much current for the same power as the 8 Ohm driver, to safely handle this extra current the voice coil wire needs to be different (thicker, shorter). As a rule of thumb the BL (Newton/ Ampere) is 1.414 times as low. The Re of a 4 Ohm driver is usually not exactly half that of the 8 Ohm driver, therefor Qes will also be different. So now you have a different BL, Re, Qes and Qts so that the 4 Ohm driver will behave the same as the 8 Ohm driver. The offset Qes can but doesn't have to be compensated for by a different Vas, etc.
Best regards Cubo
Ideally it does not but power handling is simply a measure of how much (thermal) energy the driver can handle before it burns up. If Qes, Le, etc. are different enough, it can affect the sound, although these differences are least noticeable in bass and sub enclosures.
you're saying a 4 ohm version sub rated 1200watts will sound different as compared to the same model 8 ohm version sub
As far as 15" drivers go, it's actually a pretty good Cubo Sub driver. For a 15" driver that's a very respectable Mms.
ss the RCF LF15G400 a good driver for the cubo sub?