Amp power rms for SLA Pro loaded with 2x Eminence Pro 5W and HF

[Mkulu]

Looking to experiment with the SLA Pro using the above drivers.
Intend to use two channels driving 2 x Cabs each.
It's a starter for a larger array but want to run an amp for 4 cabs with a little bit of headroom.
My feeling is 150W rms per channel, each cab wired in series and then parallel with its partner.
No EQ, the EQ from the mixer will be sufficient.
Sub amp will be seperate, various combinations are suitable as per Bill's recommendations.
I haven't bought the plans as yet.
Hurry please the amps I am building at the moment.......
What do the guys suggest?

[DJPhatman]

The 2-driver SLA Pro utilizes 2 Alpha 6a drivers, not the Pro 5W-8.

That being said, The Alpha 6a has a maximum voltage limit of 28VAC, or 100 watts @ 8Ohm, so 2 in series can handle 56VAC, or 200 watts @ 16Ohm. The great thing about tops is they will let you know if you are pushing them too hard.


Just so you know, we speak in Volts, not watts. Voltage can be measured quite easily, and is almost always a constant setting irregardless of the load, using a common Digital Volt meter, or DVM. Typically, we recommend picking up a DMM, or Digital Multi-Meter, as they are more common and much more useful doing other electrical work.

[Mkulu]

The 2-driver SLA Pro utilizes 2 Alpha 6a drivers, not the Pro 5W-8.

That being said, The Alpha 6a has a maximum voltage limit of 28VAC, or 100 watts @ 8Ohm, so 2 in series can handle 56VAC, or 200 watts @ 16Ohm. The great thing about tops is they will let you know if you are pushing them too hard.


Just so you know, we speak in Volts, not watts. Voltage can be measured quite easily, and is almost always a constant setting irregardless of the load, using a common Digital Volt meter, or DVM. Typically, we recommend picking up a DMM, or Digital Multi-Meter, as they are more common and much more useful doing other electrical work.

Hi DJ, I am aware of all that , just quoting watts is easier.Always check out the VAC.
The 5W is refered to by Bill in the latest advert for his plans.He updated them due to Eminence making these new smaller drivers.
Yip for sure Tops always let you know,like rice crispies.Snap Crackle and POP!!!

[DJPhatman]

The 5W is refered to by Bill in the latest advert for his plans.He updated them due to Eminence making these new smaller drivers.

I would still double check about using the Pro 5W-8 in a 2 driver SLA. I don't have UTD plans, but usually Bill posts recommended driver additions and omissions on the forum, and I have seen no such post. Still, I would build them with Alpha 6a drivers, anyways. I have used Alpha 6a in another build, and liked them, a lot.

No matter which driver you use, calculate maximum input power as Pe. Alpha 6a = 100 watts, Pro 5w-8 = 75 watts.

[NukePooch]

As per the plans, and the main SLA Pro website page, SLA Pros with 5W-8 can be built in 2 or 4 driver versions. SLA Pros with Alpha 4's are 4-driver cabs, 2-driver cabs are "not recommended". The 4/5" cab size is quite a bit smaller than the 6" cab size... Not as loud, of course, but useful when a small cab is needed. I still want to build a pair of 4" cabs...

My only issue with using the 5W is that here in the US, they cost $60/ea...$20 MORE than the Alpha 6 ($40/ea)... The Alpha 4's are only $30 for a PAIR.