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A force canceling subwoofer for implementing DBA's ( and Trinnov variant) around the periphery of a videowall based on the Purifi PTT10.0X04-NAB-01.

CINERAMAX

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This is a Quad Variant on the dual opposed concept. It is particularly useful in the new niche market, as the top videowall engineers are always extremely cautious regarding subwoofer placement. Videowalls resemble jigsaw puzzles, exhibiting a delicate sensitivity to vibrations that cause them to open up.

It is an-In bulkhead sealed design, the port is covered with wood lattice that is acoustically transparent to bass.
lattice work specs:
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The concept (based on dual opposing 12's) was enthusiastically endorsed by Arnaud Laborie at CEDIA. He even sketched it and offered a 10 % displacement variant that allowed for a larger cinemascope aspect ratio screen.
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The original design explored reaching 125 db @ 7hz with the 8 inch variant whose charts are here.
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The original plan with DSP, we make a Linkwitz Transform to give it more boost in the bass. Here I have boosted it down to 12Hz Q0.71 and shown the results with 2V peak on the speaker

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Unfortunately, the 8-inch Purifi was found to be insufficient, as third-party peer review revealed. Additionally, we had neglected to consider room gain. German dBa experts suggest that room gain typically ranges from 7 to 9, while the English collaborator, associated with all Trinnov demonstrations and numerous dealer showrooms, indicated a room gain of up to 14.

A quick and dirty recalculation based on the 10-inch model indicates:

If the goal is still to achieve 125dB at 7Hz, then upgrading to the 10-inch model will be advantageous due to its higher excursion and larger cone area. Following similar calculations:

- A single PTT10.0X04-NAB-02 in a 35L enclosure, DSP corrected so that 7Hz is 10dB down, results in an SPL of around 91dB @ 7Hz within the driver's maximum excursion.
- With a 7dB room gain, this increases to 98dB. Therefore, an additional 27dB is required, equating to 4.5 times more woofers, or about 23 woofers. Consequently, it might be prudent to increase this number to 32 woofers, arranged in an 8 x 4 configuration.

Thus, it appears feasible to achieve the desired outcome with the 10-inch model.
 
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