Friday, 31-Mar-2006, 04:50:06 GMT
Last modified: 04-Mar-2004, 01:20:22
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http://ldsg.snippets.org/vendors/peerless.php3
Vendor guidelines - Peerless: |
Peerless is a sister company to Scan-Speak and Vifa, all owned by Danish Sound Technology [now Tymphany]. Although Peerless makes a competent full line of drivers, it is best known for its woofers, subwoofers, and mid/bass drivers. The standard and CC lines feature PP cones, while the CSC and CSC-X (CSX) lines feature proprietary composite sandwich cones. The CSX line adds an advanced magnet structure with a shorting ring to improve linearity. Peerless has also recently introduced a new HDS line of cast frame, high-displacement drivers using CSX motor and cone technology. Based on my respondents, all of Peerless' woofers, subwoofers, and mid/bass units - and especially the CSC and CSX lines - can be recommended. All you need to do is to check the curves and numbers to determine which units will work best in your planned project. Some drivers worthy of special consideration include:
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Passive radiators: |
Passive radiators (PR's), are also known as auxiliary bass radiators (ABR's) and "drone cones". Simply stated these are woofer/subwoofer chassis with cones but no motor. The only characteristics of PR's are their excursion limit, compliance, and their resonant frequency (determined mostly by cone mass). PR systems use one or more woofers in a sealed box with a PR. Since the box is sealed and the PR has no magnetic motor, the PR's motion is entirely determined by the air in the enclosure and the back wave of the woofer(s). System design and modeling are exactly as for a ported system, except the port tuning is replaced by adjusting the PR's mass to match the mass of the air in an equivalent vent with the same cross-sectional area as the Sd of the PR. For best results, the PR should therefore have low mass, a compliant suspension capable of wide excursions, and a resonant frequency below both the box and port tuning frequencies. Any DIY'er can make a PR from an old woofer by simply removing the magnet and voice coil assembly, leaving only the chassis and cone. This is generally not a good idea. The PR's "Xmax" will be equal to Xsus of the driver. Without the constraints of motor design, PR designers can achieve outrageously high vales of Xsus. As might be expected, along with the PR's typically compliant suspension, this raises Vas considerably. Furthermore, good PR's typically use much more massive cones than drivers, resulting in a subsonic Fs and a very high Qms. For more professional (and cosmetically pleasing) results, there are several commercial sources of PR's listed below. The currently preeminent source for general purpose PR's is Stryke Audio. There are several vendors who produce PR's specially designed to work one or more of their own drivers. For more information on PR's in general, read "Passive Radiator Enclosures: In Theory and In Practice" by Adam Bird. |
PR Details: |
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