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Peter Wieck[_2_] Peter Wieck[_2_] is offline
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Default Amplifier for passive subwoofers

On Wednesday, August 15, 2018 at 1:04:38 PM UTC-4, Howard Stone wrote:

(a) The Subwoofers are rated at 250W at 8 ohms and has a basic sensitivitv of 86dBW at the 16ohm setting. Heres some more technical data

€œInside the speaker box is a pair of 260mm pressed-steel-chassis bass units, pulp coned and fitted with low hysteresis half-roll surrounds of foam polyurethane. Placed side by side on the open baffle, one faces forward and the other back, providing some balancing of linearity.
The Gradient employs two low-frequency drivers in each cabinet, arranged as an open-baffle linear array to give dipole operation. 6dB per octave boost needs to be applied throughout the low frequency range to offset the falling open baffle response, and the bass units used need a linear, high excursion capability; ± 12mm is quoted. Before overload is reached, the degree of boost must be limited and this sets the degree of bass extension available. In this sense the SW63 is not a true sub-woofer in that it does not go that final 10Hz down to 20Hz. However, it does extend the power response of the Quad by almost an octave, whilst simultaneously increasing the dynamic range and linearity of the main system.€

(b) Solid state

(c) I listen to organ, harpsichord, small vocal ensemble

(d) used or vintage


Thank you for that level of detail! And your listening spectrum, while exacting is not terribly difficult.

Creek, Cambridge Audio and B&W come immediately to mind as being readily available on the used/vintage scene in GB, have decent reputations and are also reasonably well made.

https://www.ebay.co.uk/itm/B-W-Bower...AOSwX05bbGW O

Or

https://www.ebay.co.uk/itm/Cambridge...AOSwuc1baWW 2

Will have ample power for your application and not even threaten to clip.

https://www.ebay.co.uk/itm/CREEK-EVO...AOSwQrJbYdB E

Maybe.

Peter Wieck
Melrose Park, PA