N802's: 4 ohms or 8 ohms? - B&W's recommendation

[McGlentosh]

I've read so much info and advice regarding which taps to use when connecting N802, in this and other forums, that my head was spinning, so I e-mailed B&W to get their recommendation, as follows:

"I am powering, via bi-wiring, my N802's with a McIntosh MC352 amp. The
speaker manual says the 802's impedance is 8 ohms nominal (3.5 ohms
minimal). McIntosh recommends attaching the 802's to the 4 ohm taps on the
amp. What do you recommend, and why?"

And this was their reply:

"Thank you for purchasing B&W! We specify the Nautilus 802s as a nominal 8
ohm impedance loudspeaker, and do recommend that you connect the speakers to the 8 ohm taps for best performance. In the past, consumers with this same scenario have advised upon listening to the speakers using both taps, that the 8 ohm taps do perform better with their N802s.

Best Regards,
Michael Sheehan
B&W / Rotel

Comments?

[RebelMan]

Sounds pretty clear to me, use the 8 ohm taps.

The impedence curves for the N802s will dip down to 3.5 ohms but only for a fraction of the frequency response. Usually, the higher end 800 series speakers will average between 6 and 7 ohms nominal impedence. Therefore, I believe your speakers and your amplifier are best served using the 8 ohms taps. According to your reply from B&W, it seems they, and their customers with similar setups, concur.

[jim777]

Why not just try it, and pick the one that sounds the best for you. You won't break anything

B&W employees are going to say use the 8 ohms tap so that you get the most power.
McIntosh employees are going to say use the 4 ohms tap, because you are being more gentle on the amp (and frankly you don't need to be gentle with it). If the speakers are really 8 ohms, you are using only half of the available power.

I think that you will end up using the 8 ohms tap because the N802 must be able to handle 350Watts. If you listen at lower volumes, maybe the 4 ohms tap will sound better.

I don't have that problem because the MA6500 is fixed at 4 ohms and doesn't have the famous autoformer. Who cares, it sounds great

[McGlentosh]

Thanks, Jim. I did just that (tried 8 ohm vs. 4 ohms) and I preferred the sound at 8 ohms. The first thing I noticed was a drop in the levels at 4 ohms, so I jacked up the volume via setup on my MX135 to equal the 8 ohm level (80db), using a sound pressure meter. So the quantity of sound wasn't the issue; it was the quality.

At the 8 ohm taps, there was a more open and dynamic character to the sound, with a bigger stage. By contrast, the 4 ohm tap sound was more solid and relaxed in presentation. Although I prefer the sound at the 8 ohm taps, lately I find myself doubting my own ears. Am I the only one who feels this way or hears the difference? There seems to be an overwhelming preference for the 4 ohm taps by those who respond to this forum, so maybe that "relaxed, in-the-box" sound is the way the N802's are supposed to sound.

I guess the bigger question is, WHY is there a sound difference, technically, and which sound is "right"?

[jim777]

Why (technically) - because the damping factor is twice as much on the 4-ohm tap. Because of that, I guess that the 8-ohm tap must sound more "tube" like.

BTW, you did the test the right way (with the same sound level).

[Andrew M Ward]

BTW, you did the test the right way (with the same sound level).

Dude!
Louder is better!!!

8)

[jim777]

Dude!
Louder is better!!!

8)

Louder will sound better, but imagine when it sounds better even at the same volume :P