, Various, Spectra segmentation

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Mike Beck2004-02-23 22:21

Andy, Please clarify the segmentation for the Spectra Series. I believe they are electrically segmented to have 3 segments per panel. According to the schematics there is a narrow segment driven full-range, a larger section driven mid/low range, and the last/largest segment driven with low frequency only?
This would require 3 wire connections per stator plus bias for 7 wires total? Also, how were the segments configured for the panel-narrow in the middle (symmetric) or along one edge? How were the multiple panels configured to maintain imaging in the array? Thanks for the information.

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Andy Szabo2004-02-23 22:21

Each Spectra panel is electrically divided into two parts, not three. The two halves are physically identical to each other, and physically identical to all other sectors in the speaker. The difference is how each sector is wired to the interface. For illustration purposes, let\'s look at a Spectra 22 or 2200, which is the smallest implementation possible for a full range Spectra. This speaker has two panels, and therefore four sectors. For the left hand speaker, starting at the left edge, the first sector is lows only. The second sector is mids and lows only. The third sector is full range, and finally, the fourth sector is another mids and lows only. The speaker effectively becomes narrower as frequency increases. The right hand speaker is wired as a mirror image of the left.

The Spectra 33 or 3300 has three panels, or six sectors. The extra two sectors (at the left edge of the left speaker) are wired for lows only. Note that all full-range Spectra models are the same except for the number of sectors devoted to bass reproduction: all sectors carry lows, three sectors carry midrange, and only one sector carries high frequencies. This is why all Spectra models, regardless of size, have very similar imaging characteristics. This is definitely not the case for the pre-Spectra models.

Hybrid systems, like the Spectra 11 or 1100, use only one panel, or two sectors, per speaker. Again looking at the left speaker, the left sector is mids and lows only (above 150 Hz), and the right sector is full range (above 150 Hz). Everything below 150 Hz is crossed over to the woofer.

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