bigboss said:
If I was in the market for some speakers, and if AVI stated, for example, 50w into 8 ohms, I would feel cheated, because there's no 8 ohms in it! What would you suggest for this shadders? You cannot compare passives with actives this way at all. If people compare performance between actives and passives this way, they need education as to how to compare specs, not follow their wrong path to satisfy what they're looking for.
I'm afraid you are incorrect. You certainly can (and should) compare active speakers with passive speakers this way.
Remember that an amplifier is an ampifier, irrespective of whether it will be fitted directly to the speaker drivers or not. It has a certain measured output into a certain load which it can sustain for long periods of time, but is also capable of sustaining short bursts of power, otherwise known as peak power. All amps are built this way.
Speaker drivers also have a maximum rated power, after which they will begin to break up. The load they present to the amplifier may be 6, 8 or 4 ohm, although in actual fact some can dip as low as 2 ohm. These loads provide degrees of difficulty for the amplifier, if you like. All passive speakers should, and generally do, give power and load ratings, for example 60W to 80W, 8 ohm. This figure is based on the speakers drivers used.
The crossover basically ensured that the individual driver works at maximum efficiency within its designed frequency range, and, amongst other things, limits the frequency each driver sees. Again, it doesn't matter whether the crossover is active or not, they all function the same way. That's a simplified picture, of course.
Now, a continuous power rating gives an idea of the power of the amplifier. It does change according to load - 50W into 6 ohm could be 45W into 8 ohm or 90W into 4 ohm. The figure does depend on amplifier design, but you get the idea. How you measure continuous power is a bit of a minefield and it is not uncommon for some makers to state lower figures than what the amplifier can actually handle, either for safety reasons or so they look good in reviews, if you believe the cynics.
That's why the continuous power rating, flawed though it may be, does give an idea of how an amplifier will perform with a given load. It was originally introduced in the US (I think) to prevent manufacturers using peak power figures to rate their amps. These figures were highly flattering, given peak power can be 5 times higher than continuous power, but ultimately misleading. Even now some amplifier manufacturers quote continuous power into 4 ohms as the figure always looks better - one French company only gives figures for 4 ohms, so their 100W is really only about 55W into 8 ohms, and not ideal to drive speakers which require 60 - 80W into 8 ohms.
So, you should not feel cheated with the 50W into 8 ohms, as that's (and this really is an approximation) 70 W into 6 ohms or 90W into 4 ohms. However, you should ask questions if a manufacturer uses some other yardstick instead, such as peak power or half peak power. For active speakers, then, continuous power figures, however flawed, are useful as they can give an idea of what to expect. AVI could easily provide more realistic figures, but they have chosen not to do so as it's another way of selling what they want people to believe is an exclusive niche product. Whether it has been successful is a different matter, and you would expect to see changes in marketing strategy if they are taken over and move into the mainstream.
Facebook
Twitter
Instagram