Hi,
would like to settle this once and for all.
A few years ago now, I posted on usenet about testing the Mackie SW1501 amp
module on the bench with a sine wave at 8 ohms. They blow up. Well mine
did and I had to mend them again.
I'm pretty sure it was Phil Allison who pointed out that the amp circuit is
not capable of full sinewave power at 8 ohms without exceeding the
transistor specs.
Here is the schematic, it specifies a 12 ohm driver.
http://www.eserviceinfo.com/downloadsm/54201/mackie_swa1501.html
Googling for replacement drivers brings up recommendations by Eminence that
you use one of their 8 ohm drivers.
http://www.guitarcenter.com/Eminence-Omega-Pro-15A-PA-Replacement-Speaker-667713-i1153808.gc
It also brings up that originally, (apparently), Mackie used an RCF driver,
and later went on to use a modified P-audio C15-300MB. I don't know if
these were 16 ohm or 8 ohm drivers.
http://forum.speakerplans.com/driver-for-mackie-sw1501_topic23338.html
So I have another customer with one of a pair of these subs that needs a new
driver.
In the past I have instructed my local reconer to put a 16 ohm coil in these
(he rolls his own).
I suspect this is by far the best plan, but would like some confirmation or
further info if anyone has any.
Cheers,
Gareth.