Lab12 Impedance

[Bryan Cox]

I just read that the Lab12 is a 6 ohm woofer. My amps all are capable of running 2 ohm loads. But if I Daisy chain two Lab12s per side... Wouldn't the 3 ohm load significantly shorten the life of my amp? Would you guys recommend just running one per side? I'd really rather spend the extra scratch up front and run the speakers safely rather than have an amp fail during a gig. Thoughts?

[Grant Bunter]

I just read that the Lab12 is a 6 ohm woofer. My amps all are capable of running 2 ohm loads. But if I Daisy chain two Lab12s per side... Wouldn't the 3 ohm load significantly shorten the life of my amp? Would you guys recommend just running one per side? I'd really rather spend the extra scratch up front and run the speakers safely rather than have an amp fail during a gig. Thoughts?

Sure, avoid the issue to a large extent and use 3012lf's instead.
2 cabs per side is then 4 ohms.
Much the same price as the lab 12, and around 14 pounds per driver lighter...

[Bryan Cox]

I also read on here that when installed, a Lab12 acts as an 8 ohm load. Not quite sure I understand that one. I am considering the 3012LF as an alternative. I was trying to get the most bang for the buck out of four cabs.

The 3012LF is 496cc Vd and the Lab12 is 659cc Vd. I've seen other threads dance around the topic. But how much does the Vd really correlate to the output of these two drivers?

[Grant Bunter]

I also read on here that when installed, a Lab12 acts as an 8 ohm load. Not quite sure I understand that one.

The cab (all Bill's horn sub designs) adds 2 ohms in acoustic impedance. So, similarly, a 3012lf loaded cab acts as a 10 ohm load.
Still, my personal preference, especially when trying to match drivers to amplifiers, is to ignore acoustic impedance.

I am considering the 3012LF as an alternative. I was trying to get the most bang for the buck out of four cabs.

The 3012LF is 496cc Vd and the Lab12 is 659cc Vd. I've seen other threads dance around the topic. But how much does the Vd really correlate to the output of these two drivers?

Vd is most useful when trying to compare to lower drivers with lower Vd, eg 1 lab 12 is equal to 2 x BP102's.
In the plans, you will see both drivers are voltage displacement limited to 50V.
It gets shortened to volts, but Voltage displacement limits, as set by Bill, have numerous factors.
The top 2 most important factors are impedance and Xmax, and then the rest of the TS specs come into play as well.
Because the Lab12 is nominally 6 ohms and the 3012lf nominally 8 ohms, the lab 12 wins with the same 50V limit.
By how much? About 1, maybe 2 dB. Almost insignificant.
Given the weight penalty for the Lab12, IMHO, not worth it...

[Bryan Cox]

That's what I was looking for, Grant. Thank you!