House curves and power required in IBs

[chrisbee]

I'm not sure this has been covered specifically though it might have mentioned in a number of threads.

Thomas has repeatedly mentioned the ease of driving an IB subwoofer at the lower frequencies.

Does this mean that house curves are independant of power input?

Let's say you set a positive +3db filter on your BFD at higher frequencies. (say somewhere between 50-80Hz)

I believe it would take double the amplifier power to drive that frequency to the same level as all the other frequencies around it.

So what happens to amp power equirements at much lower frequencies when you introduce a broad house curve?

Does the power requirement rise as it would with a narrow, higher frequency filter?

Or does the ease of producing VLF with an IB offer free output for the same power or less?

[ThomasW]

chrisbee said:

Thomas has repeatedly mentioned the ease of driving an IB subwoofer at the lower frequencies.

Does this mean that house curves are independant of power input?

Any forum of EQ, house curve or other, for any type of loudspeaker, is dependent on variations in the amount of power being used.

Let's say you set a positive +3db filter on your BFD at higher frequencies. (say somewhere between 50-80Hz)

I believe it would take double the amplifier power to drive that frequency to the same level as all the other frequencies around it.

Correct

So what happens to amp power equirements at much lower frequencies when you introduce a broad house curve?

Does the power requirement rise as it would with a narrow, higher frequency filter?

The power needed to increase output +3dB is independent of the frequency

Or does the ease of producing VLF with an IB offer free output for the same power or less?

IB's decrease the air spring pressures on the drivers. That increases the power to SPL ratio, resulting in increased output below Fs, and requiring lower amounts of power to do this. The downside to this approach is the lower max SPL achievable per sweep area. This is another reason for the recommend of a very high Vd for IB subs.

[jman]

Thomas-

how much more efficient is an IB compared to something like Bossobass's small, quad Tumult sealed LT setup?

[ThomasW]

jman said:

Thomas-

how much more efficient is an IB compared to something like. Bossobass's small, quad Tumult sealed LT setup?

The efficiency is the same regardless of the alignment (horns being the obvious exception.)

[chrisbee]

Thankyou, Thomas