Benefits of an external amp for my Denon X3800H with Kef LS50 Meta?

[napfkuchen]

My L/C/R speakers are already active and the LS50 Meta are known for being power-hungry (85 dB efficiency), I've been considering buying an additional external amplifier.
Since switching to Dirac ART, I've noticed that I have to set the Denon to between -20 and -16 for my "comfortable" volume. Would it be worthwhile to reduce the load on the AVR, or does it not matter as long as the power output is sufficient?

My current choice, due to its compact dimensions (it still needs to fit in a closed lowboard...), would be this Audiophonics amp:
Audiophonics HPA-H250NCX

(Heat generation doesn't seem to be an issue. Since the Denon only needs to power 6 surround channels anyway, and I have an AC Infinity unit on top, the unit always stays cool.)

 

[skankhobag]

I own LS50s and have them powered by a Parasound A23 amp (100 W). That will take the KEFs to their limit of 105 dB.

Unless you’re having a problem with your AVR clipping (doesn’t sound like you do), I’m not sure why you would need any more amplifier power.

The only thing you need to do with those speakers is not feed them low bass. You have to use a subwoofer(s) to get the best out of them.

 

[napfkuchen]

Thanks for the confirmation, I'm going to leave everything as is. Crossover is set to 85 Hz right now.

 

[Head_Unit]

I have to set the Denon to between -20 and -16

You're not clipping, all is well. Aside from whatever your subwoofer is, and if you've run the Audyssey, the next upgrade would be to like R3 or whatever, a 3-way Meta. KEF has done a lot of engineering work evolving the Uni-Q but the one Achilles' Heel is the more the woofer cone moves the more it modulates the treble response since it is essentially a horn to the tweeter. A 3-way with another woofer* leaving the Uni-Q cone just for mids reduces that vastly. (*or two woofers-nothing wrong with a center channel model rotated to vertical, since the Uni-Q is axisymmetrical)

 

[Oddball]

Thanks for the confirmation, I'm going to leave everything as is. Crossover is set to 85 Hz right now.

You mean lower end of ART support range for the KEF's?

 

[napfkuchen]

You're not clipping, all is well. Aside from whatever your subwoofer is, and if you've run the Audyssey, the next upgrade would be to like R3 or whatever, a 3-way Meta.

I chose the LS50 Meta because of the short distance to the speakers (1.70m at the back and 2.20m at the front) and their slightly better directivity compared to the R3s. Also, the "entertainment" area in my living room is only about 4x4.5m, and there needs to be a passageway to the balcony behind the couch. Every centimeter counts.

I also don't see the R3s as a "bass monster" (F3 = 58 Hz vs. 79 Hz for the LS50 Meta). The plan for now is to wait until the next Black Friday and then buy two Buchardt SUB10s to place on the back wall. I might then raise the support frequency for the LS50s a bit, although even at my preferred listening level, you can't see any cone movement or hear any distortion. Even with that, I probably won't be able to significantly improve the sound any further, as I'm already very satisfied with it (diminishing returns?).

You mean lower end of ART support range for the KEF's?

exactly

 

[Oddball]

I chose the LS50 Meta because of the short distance to the speakers (1.70m at the back and 2.20m at the front) and their slightly better directivity compared to the R3s. Also, the "entertainment" area in my living room is only about 4x4.5m, and there needs to be a passageway to the balcony behind the couch. Every centimeter counts.

I also don't see the R3s as a "bass monster" (F3 = 58 Hz vs. 79 Hz for the LS50 Meta). The plan for now is to wait until the next Black Friday and then buy two Buchardt SUB10s to place on the back wall. I might then raise the support frequency for the LS50s a bit, although even at my preferred listening level, you can't see any cone movement or hear any distortion. Even with that, I probably won't be able to significantly improve the sound any further, as I'm already very satisfied with it (diminishing returns?).

exactly

If you are happy with the bass as-is, graphs look reasonable well, and you get SPL you want, then it is all good. More subs might do a bit better to further even out frequency response (if needed at all), will probably further reduce decay, and will give you a bit of a headroom for higher SPL, and also lower distortion - if any of those are needed at all.