konsl
New Member
I'm currently trying to design an enclosure for the 416-8A, and experiencing some challenges.
First, I can not find any T/S parameters for this speaker. I can find them for the 416-8B (incorrect in original documentation, and correct numbers derived in the 1980's found here: http://alteclansingunofficial.nlenet.net/Thiele-Small.html). The problem is that the 416-8A is different than the 416-8B (their free air resonance frequencies are 25Hz and 24Hz, respectively).
Second, I don't know what kind of port size I need for an arbitrary sized cabinet. I'm trying to alter a 612C cabinet slightly to increase the volume to >= 7.25 cu ft (7 cu ft when removing the 0.25 cu ft the speaker displaces). I've read that the 416-A/B/C/Z requires at least 7 cu ft to become effective. The official Altec literature says ~14 sq inch port for a 612C (source: http://alteclansingunofficial.nlene...letters/AN-5_CustomizingAltecLFEnclosures.pdf), but that seems really small. I've also read that Altec literature can be incorrect and/or contradict itself. How do you calculate the "optimal" port size, or at least the minimum port size?
Does anyone have any advice, experience, or documentation that could help my project?
Additional context: I want a multi-genre speaker system for a large, rectangular room (17 x 45 ft - 765 sq ft with 12 ft ceilings). I'm putting custom horns on top (outside of the enclosure) that will crossover at 800Hz. Will play jazz/classical/soul via vinyl, but also use for regular listening like hip hop and house music. I'll likely improve the latter with the addition of a subwoofer?
Thank you!
First, I can not find any T/S parameters for this speaker. I can find them for the 416-8B (incorrect in original documentation, and correct numbers derived in the 1980's found here: http://alteclansingunofficial.nlenet.net/Thiele-Small.html). The problem is that the 416-8A is different than the 416-8B (their free air resonance frequencies are 25Hz and 24Hz, respectively).
Second, I don't know what kind of port size I need for an arbitrary sized cabinet. I'm trying to alter a 612C cabinet slightly to increase the volume to >= 7.25 cu ft (7 cu ft when removing the 0.25 cu ft the speaker displaces). I've read that the 416-A/B/C/Z requires at least 7 cu ft to become effective. The official Altec literature says ~14 sq inch port for a 612C (source: http://alteclansingunofficial.nlene...letters/AN-5_CustomizingAltecLFEnclosures.pdf), but that seems really small. I've also read that Altec literature can be incorrect and/or contradict itself. How do you calculate the "optimal" port size, or at least the minimum port size?
Does anyone have any advice, experience, or documentation that could help my project?
Additional context: I want a multi-genre speaker system for a large, rectangular room (17 x 45 ft - 765 sq ft with 12 ft ceilings). I'm putting custom horns on top (outside of the enclosure) that will crossover at 800Hz. Will play jazz/classical/soul via vinyl, but also use for regular listening like hip hop and house music. I'll likely improve the latter with the addition of a subwoofer?
Thank you!
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