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/download...e_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...13-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...opic23338.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.

"Gareth Magennis"


So I have another customer with one of a pair of these subs that needs a
new driver.


** New driver or a repair done ?

Watch out for ambiguity.


In the past I have instructed my local reconer to put a 16 ohm coil in
these (he rolls his own).

** Then surely he can also "roll" a 12 ohm coil.

Makes only 2dB difference in sensitivity and none to the max dB output at
LF.



.... Phil

"Phil Allison" wrote in message
...

"Gareth Magennis"


So I have another customer with one of a pair of these subs that needs a
new driver.


** New driver or a repair done ?

Watch out for ambiguity.


In the past I have instructed my local reconer to put a 16 ohm coil in
these (he rolls his own).

** Then surely he can also "roll" a 12 ohm coil.

Makes only 2dB difference in sensitivity and none to the max dB output at
LF.



... Phil



I will ask.
He generally pre-rolls his coils in batches so he can just grap them from
stock.
This would have to be a one-off special, so I shall have to talk to him
nicely.


Thanks for the info,


Gareth.

Well, I've just contacted Loud Technologies for price and availability, and
the part they are now using is:

Eminence Kappa 15B custom 15 ohm.




Gareth.

"Gareth Magennis"

Well, I've just contacted Loud Technologies for price and availability,
and the part they are now using is:

Eminence Kappa 15B custom 15 ohm.


** How ****ing amazing ........

" Desperate picks do desperate tricks ..... "




.... Phil

"Phil Allison" wrote in message
...

"Gareth Magennis"

Well, I've just contacted Loud Technologies for price and availability,
and the part they are now using is:

Eminence Kappa 15B custom 15 ohm.


** How ****ing amazing ........

" Desperate picks do desperate tricks ..... "




... Phil




Funny, I had a customer bring me 2 of these SWA 1501 amp modules he'd blown
up. He bought just the modules, not the cabinets.
He has brought stuff to me before he's removed from cabinets and tried to
fix himself, and blown everything up in the process. He's a DJ and meddles
with all his gear.

I refused to repair them, because I just know he's probably put 4 ohm
drivers in those cabinets, and will blow them up again and bring them back
to me forever.

Its not often I refuse people just because of who they are, but this guy is
a total disaster and doesn't listen to or understand anything.
His father pays the bills, and he's got loads of money, and actually
understood why I wouldn't repair them, eventually.



Gareth.

"Gareth Magennis"

Well, I've just contacted Loud Technologies for price and availability,
and the part they are now using is:

Eminence Kappa 15B custom 15 ohm.


** How ****ing amazing ........

" Desperate picks do desperate tricks ..... "


Funny, I had a customer bring me 2 of these SWA 1501 amp modules he'd
blown up. He bought just the modules, not the cabinets.
He has brought stuff to me before he's removed from cabinets and tried to
fix himself, and blown everything up in the process. He's a DJ and
meddles with all his gear.

I refused to repair them, because I just know he's probably put 4 ohm
drivers in those cabinets, and will blow them up again and bring them back
to me forever.

Its not often I refuse people just because of who they are, but this guy
is a total disaster and doesn't listen to or understand anything.


** He's a DJ, that is all the info we need.

Donkeys have a higher IQ.




..... Phil

"Phil Allison" wrote in message
...

"Gareth Magennis"

Well, I've just contacted Loud Technologies for price and availability,
and the part they are now using is:

Eminence Kappa 15B custom 15 ohm.


** How ****ing amazing ........

" Desperate picks do desperate tricks ..... "


Funny, I had a customer bring me 2 of these SWA 1501 amp modules he'd
blown up. He bought just the modules, not the cabinets.
He has brought stuff to me before he's removed from cabinets and tried to
fix himself, and blown everything up in the process. He's a DJ and
meddles with all his gear.

I refused to repair them, because I just know he's probably put 4 ohm
drivers in those cabinets, and will blow them up again and bring them
back to me forever.

Its not often I refuse people just because of who they are, but this guy
is a total disaster and doesn't listen to or understand anything.


** He's a DJ, that is all the info we need.

Donkeys have a higher IQ.




.... Phil




Oh, just remembered, he actually brought me 3 of these blown up. The third
one was one he'd borrowed off a mate to see if it was his amps or his
speakers that were dead.


Hee Haw.