4 ohm vs. 8 ohm

Early B.

Aside from power considerations, is there a reason why one would prefer a 4 ohm speaker to an 8 ohm speaker, or vice versa? Is there a preference for sonic reasons?

Thanks.

disneyjoe7

As modern speakers go why did we go from 16 ohms to 8 ohms, just because of Solid State vs. Tubes? So why 4 ohms not 8 ohms is a good question as some speaker as we know are 4 ohms. I can see the reason in car audio for the lower impedance, but then we don't really feel that car audio is really clean. Car audio may not need to be clean due to road noise issues, so why the lower impedance in home audio? I always felt that some speakers are 4 ohms due to the need for a flatter audio curve that some crossovers are designed for this causing the lower impedance.


All in all a good question.

gregure

Generally, lower Ohm speakers have more sophisticated (read: expensive) tweeter technologies than 8 Ohm speakers. The 4 Ohms tend to be silk tweeters, ring radiators, ribbons, transducer films, and electrostatics, although there are some variations that run at 5 or 6 Ohm nominal impedance. It's not to say that 8 Ohm aren't as capable of producing quality music playback, but the reality is that most truly high end speakers are 4 Ohm. They have a different sound, and almost always require expensive gear to run them properly, although some 4 Ohms sound pretty good on lesser products such as Denon, HK and Onkyo receivers in the $800-$1200 range. Again, I say lesser in comparison to high end gear, such as separates or receivers that retail for $3000 or more.

All in all, higher end speakers with such tweeters as listed above tend to be less bright, more tonally balanced, and have tremendous imaging and detail. However, for movies the 8 Ohm, metal dome tweeter speakers seem to still be the best fit, although there are obviously different levels of quality within that range as well. In my experience, though, you will almost never see a metal dome tweeter (aluminum, titanium, etc.) that runs less than 8-6 Ohms nominally.

shiu

Greg,

I know of some high end speakers that use metal dome tweeters. Can you name a couple that use silk? I am just curious, thanks.

gregure

All the speakers from Vienna Acoustics use silk tweeters, as did the entry level Sonus Faber, although those are now being replaced with ring radiators, which is what SF uses for all of their other speakers.
M&K also uses soft domes, although, since they are so geared toward movies in the retail models, they tend to be brighter than other soft dome speakers.
Martin Logan obviously uses electrostatics, but their entry level and on-wall speakers use transducer film for tweeters and mids.
The new Summit electrostatic from Martin Logan israted at 4 to .7 Ohms (!) for the highest frequencies.
Obviously the LSi line uses ring radiator, thus the 4 Ohm impedance and the frequency on the forum of discussing how they need more power to sound good.