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Compare speakers at true scale

Pick two speakers and see them side by side at their real-world size.

Speaker A
Speaker B
OverlaySide by side
Presentation mode
References

Front view — overlaid at true scale

AQuad S-4BCastle Avon 4
Quad S-4 front view
Castle Avon 4 front view

Click either cabinet to swap A ↔ B · Reference height: 955 mm (95.5 cm) · 1 mm = 0.59 px

Quad S-4vsCastle Avon 4

The Castle Avon 4 stands 95.5 cm tall — about 8.5 cm more than the Quad S-4 at 87.0 cm. At 89 dB against 88 dB, the Castle Avon 4 is the easier load to drive and plays louder from the same amplifier. The Quad S-4 is loaded by a passive radiator and the Castle Avon 4 is a transmission line.

TrueSpecs presentation

Specifications

mm / kgin / lb
AB
ManufacturerQuadCastle
ModelQuad S-4Castle Avon 4
Height870 mm955 mm
Width180 mm180 mm
Depth300 mm310 mm
Weight20.5 kg17.6 kg
Enclosurepassive-radiatortransmission-line
Drivers1× tweeter (ribbon), 1× 100 mm midrange (woven Kevlar cone), 2× 125 mm woofer (woven Kevlar cone)1× 130 mm woofer, 1× 115 mm midrange, 1× tweeter (ribbon)
Frequency — low44 Hz45 Hz
Frequency — high23000 Hz20000 Hz
Sensitivity88 dB89 dB
Impedance6 Ω8 Ω
Recommended amp40–200 W25–100 W
MAP (USD)$1,499 / pair—
Where to buyCheck availability ↗Check availability ↗
Brand websitequad-hifi.co.uk ↗castle.uk.com ↗
Product pageOpen product page ↗Open product page ↗

Larger value highlighted in green. For low-frequency extension, lower Hz = greater bass reach, so the deeper side is highlighted.