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Howard Stone Howard Stone is offline
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Default Amplifier for passive subwoofers

On Wednesday, 15 August 2018 21:43:22 UTC+1, Peter Wieck wrote:
On Wednesday, August 15, 2018 at 1:04:38 PM UTC-4, Howard Stone wrote:
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(a) The Subwoofers are rated at 250W at 8 ohms and has a basic sensitiv=

itv of 86dBW at the 16ohm setting. Here=E2=80=99s some more technical data
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=E2=80=9CInside the speaker box is a pair of 260mm pressed-steel-chassi=

s 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 fo=
rward and the other back, providing some balancing of linearity.
The Gradient employs two low-frequency drivers in each cabinet, arrange=

d as an open-baffle linear array to give dipole operation. 6dB per octave b=
oost needs to be applied throughout the low frequency range to offset the f=
alling open baffle response, and the bass units used need a linear, high ex=
cursion capability; =C2=B1 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 resp=
onse of the Quad by almost an octave, whilst simultaneously increasing the =
dynamic range and linearity of the main system.=E2=80=9D
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(b) Solid state
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(c) I listen to organ, harpsichord, small vocal ensemble =20
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(d) used or vintage

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Thank you for that level of detail! And your listening spectrum, while ex=

acting is not terribly difficult.=20
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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.=20
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https://www.ebay.co.uk/itm/B-W-Bower...-VA100-II-Int=

egrated-Amplifier/292674421961?hash=3Ditem4424c144c9:g:VHIAAOSwX05bb GWO =
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Or
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https://www.ebay.co.uk/itm/Cambridge...o-Integrated-=

Amplifier/192619789579?hash=3Ditem2cd908bd0b:g:xK8AAOSwuc1ba WW2 =20
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Will have ample power for your application and not even threaten to clip=

..=20
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https://www.ebay.co.uk/itm/CREEK-EVO...CONDITION-WIT=

H-MANUAL/123313128754?hash=3Ditem1cb6090532:g:6DcAAOSwQrJbY dBE =20
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Maybe.=20
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Peter Wieck
Melrose Park, PA


Thank you