What's the lowest impedance for JBL 4311's?

[vifa32144]

With todays amps ratings rising to 6 - 8 ohm impedances only, does anyone know the precise
impedance of the JBL 4311 Monitors?

[GordonW]

Given that the 123A/2213H and variants all have a DCR of around 4.5 ohms, this can sometimes be a problem. There's no passive crossover components, either, to "mitigate" the impedence... those woofers are wired DIRECTLY TO THE INPUTS on 4311s, L100s and such.

If your 4311s have the alnico (123A/2212) driver, the below plot should be very close to what you should expect, as far as impedence from your 4311. The high-end (mid and tweeter) aren't accounted for here, but their contribution to the load doesn't start until around 2KHz... by which time there shouldn't be enough power content in the material to make an amp 'give it up'. Note that the impedence is at a minimum, at about 4.6 ohms, at around 30 Hz and 400 Hz... very "busy" parts of the spectrum, especially on home-theatre content (movie soundtracks, etc). Personally, I'd "treat" the speaker as if it was about 5 ohms, overall... that's probably a good average representation.