Acoustic Energy 109. How to "guestimate" port tuning based on crossover point
I have all the drivers and crossover to make an Acoustic Energy AE 109.
What I do not have is the length and diameter of the port of the woofer (rear ported) and mid woofer (two front ports)
Crossover : 3-way, 8 element 12dB per octave slope at 300Hz and 3kHz with high power low-distortion toroid inductor for bass
Overall frequency response : 35Hz to 22kHz
Frequency Response : 55Hz to 18kHz [± 3db]
Based on the frequency response of 35 hz to 18khz and crossover at 300hz, can I safely assume that the port tuning of the woofer is around 45hz and 300 hz for the mid woofer ?
I do not need the design to be perfect, this would be used as a secondary system.
I have all the drivers and crossover to make an Acoustic Energy AE 109.
What I do not have is the length and diameter of the port of the woofer (rear ported) and mid woofer (two front ports)
Crossover : 3-way, 8 element 12dB per octave slope at 300Hz and 3kHz with high power low-distortion toroid inductor for bass
Overall frequency response : 35Hz to 22kHz
Frequency Response : 55Hz to 18kHz [± 3db]
Based on the frequency response of 35 hz to 18khz and crossover at 300hz, can I safely assume that the port tuning of the woofer is around 45hz and 300 hz for the mid woofer ?
I do not need the design to be perfect, this would be used as a secondary system.
IME, assume 35 Hz Fb and use a vent size that requires a bit of length for worst case of partially blocking it to raise it or make the vent such that it can be removed, shortened.
Within reason the Fs of the speaker is about the end of the road.
Not every speaker is the same obviously mechanically.
But if they claim -3 dB response around 55 Hz
Its relatively close to what the cabinet is tuned to.
50 to 55 Hz
I tend to like to tune lower or
Just use very straight forward QB3 alignment.
Be easier to determine if you had TS parameters
and just use a normal QB3 alignment.
I tend to like lower tunings if the driver allows it.
But for a very good guess-timate
basically yes tune 3 to 5 Hz above or below Fs
Or your 45 to 50Hz ish Guess is reasonable
As for a ported mid, I dont see the point...but
Thermally in high powered systems a ported mid would help
reduce heat.
But a would tune below the crossover point so the reflex
doesn't even come to play. Its just 2 holes for heat venting.
Which again seems rather pointless.
Unless excessive heat was a issue.
Not every speaker is the same obviously mechanically.
But if they claim -3 dB response around 55 Hz
Its relatively close to what the cabinet is tuned to.
50 to 55 Hz
I tend to like to tune lower or
Just use very straight forward QB3 alignment.
Be easier to determine if you had TS parameters
and just use a normal QB3 alignment.
I tend to like lower tunings if the driver allows it.
But for a very good guess-timate
basically yes tune 3 to 5 Hz above or below Fs
Or your 45 to 50Hz ish Guess is reasonable
As for a ported mid, I dont see the point...but
Thermally in high powered systems a ported mid would help
reduce heat.
But a would tune below the crossover point so the reflex
doesn't even come to play. Its just 2 holes for heat venting.
Which again seems rather pointless.
Unless excessive heat was a issue.
The two drivers in the front are woofer, mid woofer? They look like they are two of the same drivers. Is there a larger woofer side mounted we can't see in the pics or is one of those drivers playing the role of woofer and the other mid-woofer?
