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(ab) wrote in message et...
Lets say we have a 2-way speaker using a passive x-over, 6.5" mid/woofer, and
a 1" dome tweeter. Would it be correct to say that for most music passages
the mid/woofer would be drawing more power from the amp than the tweeter
would?

Unfortunately a significant piece of information needed to answer
this question is missing from your hypothetical speaker description.

The energy in the music your speaker is playing is distributed in
some fashion or another across the audio spectrum. The details
of the distribution change with the type of music, it varies from
moment to moment, and so on.

The relevant point here is tha depending upon WHERE the crossover
is placed frequency wise determines HOW the power is distributed.

Let's take a simple, though not entirely realistic case. Let's say,
for the purpose of illustration, that the spectral distribution
of the music you're playing has the characteristics of pink noise
(most music does NOT, but we're making some simplifying assumptions
here). This means that each octave across the musical spectrum has
the same power in it as every other octave. The octave spanning
40 to 80 Hz has the same total power as the octave spanning
4 kHz to 8 kHz.

Now, let's put our crossover at around 700 Hz (again, for the purpose
of illustration). This places the crossover so that the woofer handles
5 octaves and the tweeter handles 5 octaves. In this case, using our
hypothetical musica signal, half the power goes to the woofer, and
half goes to the tweeter.

Instead, let's put the crossover at, say, 5 kHz. Now, the woofer has to
handle the range from 20 to 5 kHz, which is about 8 octaves, while the
tweeter has to handle only 2 octaves. In this case, the woofer has to
handle 80% of the power, and the tweeter has to handle only the remaining
20%.

Pick real musical signals, where the spectrum is significantly different,
and you find the distribution of power is also significantly different.

Does it take more power to produce low frequencies than it does to
produce high frequencies?

Depends upon what you mean by the question.

In the simplest, most unambiguous interpretation, a speaker with
flat frequency response will require exactly the same power to
produce the same sound pressure level at ANY frequency.

But, again, you have to go back to the concept of how the musical
energy is spread across the spectrum and how the crossover divides
up the spectrum and thus the energy.

As a VERY general rule, music has most of its power concentrated
at high bass and low midrange frequencies, and the power falls
off above and below that. But, again, it's very dependent upon
the type of music and the instantaneous spectral content of
the music, which varies from moment to moment.

Now lets say we are running a 80W amp to the 2-way speaker and
we are really blasting a hip hop song with a huge bass track
and a lot of highs. Assume that the mid/woofer is drawing 50W
of power from the amp. Is the tweet able to get access to 80W
of power from the amp at the same time (since it is playing
different frequencies) or is the tweet only able to get 80w-50W=30W?

It ALL depends upon the spectral distribution of the power AT THAT
MOMENT, and it all depends upon the crossover frequency.

But to answer you more general question. If the total power of the
amplifier is 80 watts, and it's already busy using 50 watts of it
to do one, thing, then no matter what tehe other thing is, there's
only 30 watts remaining to do whatever that is.