Question about powering 5Jr+'s

sunvalleylaw

Hi, I am kind of a newb, and not very technical in terms of science and math (that is why I am just a dumb lawyer. ;-) ). But anyway, I have acquired an Onkyo TX-822 which is rated at 50w per side, but says the speakers should be 8 ohm minimum in the literature that came with the receiver. As I understand it, the 5jr+ is rated at 6 ohm. Can this receiver drive them nicely in a relatively small space? (12x20 room?)

sunvalleylaw

Here is where I am getting the info on the speakers. https://polksda.com/pdfs/MonitorReference2.pdf

F1nut

You should be fine as long as you're not trying for rock concert volume levels.

Jimbo18

I am using a 55wpc HK receiver with mine and it drives them just fine.

sunvalleylaw

Thanks. @F1nut No, would not be rock concert volumes in this small office. Might crank it up just a little after work if no one is around, but in that small space, I would guess I would not have the dial up all that high.

Also, I need to make sure I am using these numbers correctly. In the light of morning, I am seeing that all the Polk speakers at that time were rated at 6 ohms "nominal impedance." I found an Onkyo instructional manual at HiFi Engine that lists musical power output at 2 x 95 w at 4 ohms, 2 x 68 watts at 8 ohms, and continuous power output at 2 x 50 at 4 ohms and 2 x 45 at 8 ohms.

Am looking for a "Impedance for Dummies" or something sort of article or youtube video to help me understand how it works, for my edification and knowledge as I dive back into this stuff.

FestYboy

If the Denon is rated for 4 ohm, then you'll have no prob driving the 5jrs. That's the short answer. Someone with a bit more time on their hands can get down to the nitty gritty (on lunch). Just know that a speaker does not present a stable load to an amp. It curves based on frequency.

F1nut

I found an Onkyo instructional manual at HiFi Engine that lists musical power output at 2 x 95 w at 4 ohms, 2 x 68 watts at 8 ohms, and continuous power output at 2 x 50 at 4 ohms and 2 x 45 at 8 ohms.

They used to rate power a bit differently years ago. Basically forget the "musical power output" rating and go with the continuous. The sign of a beefy amp is when the 4 ohm rating is double the 8 ohm.

soundfreak1

I powered 2 pair (separate systems) of 5jr+ with a parasound 1200, krell amp 500w and no problem, just no distortion, that will cause problems not "clean power".