Quad S4 Floorstanding Speakers – Sapele Mahogany

Here we have a pair of the well regarded S4 floorstanding loudspeakers from Quad, finished in a satin Sapele Mahogany veneer. They are in good fully working condition with a light mark on the side of one speaker – please see photographs. They come supplied in original packaging, with grilles and our standard 3 month warranty.
Quad Say…….
It was way back in the mono days of 1949 that Quad launched its first loudspeaker, the Corner Ribbon. This was, indeed, a prestige product, but it offered something special, a particularly clear and detailed upper midrange to treble performance from a large and delicate ribbon driver.
…And that was 1949. So, the question is, can Quad engineers replicate this performance today, or even surpass it? the answer, not surprisingly, is yes.
The Quad corner ribbon was a speaker incomparable to competitors at its time, all with thanks to the Quad ethos, which is still adhered to in all product development and to deliver; “The Closest Approach To The Original Sound”.
Being our first ever commercially available loudspeaker, the Corner Ribbon was not completely perfect – it generated a relatively low power and the ribbon unit was very fragile. As we know founder Peter Walker moved on to develop the world’s first full range, push-pull Electrostatic speaker, if not the most iconic loudspeaker of our time.
So, to make a ribbon unit that handled today’s high power amplifiers and to do the original Corner Ribbon justice was no mean task. The S Series ribbon accomplishes this by utilising a composite ribbon sandwich substrate that is far more robust than earlier designs and immerses this ribbon in an exceptionally strong magnetic field to yield ultra-high sensitivity.
Unlike conventional dome treble units where the voice coil ‘motor’ is attached separately to the diaphragm, S Series ribbon is both the diaphragm and the motor system.
While taking influence from the unparalleled success of the ESL speaker, the ribbon itself is engineered to be extremely light and thin, which delivers the startling accuracy and wide coverage Quad is famous for.
The result is a unique combination of delicacy, smoothness and hear­ through performance that helps make your music sing.
The ribbon tweeter is aligned with Quad’s Kevlar-coned bass and midrange drivers through sophisticated crossover networks. Through our extensive and innovative approach to loudspeaker design on the floorstanders of the S series, ABRs or Auxiliary Bass Radiators have been implemented, and offer many benefits when compared with conventional bass reflex ports.
In inferior loudspeakers, air rapidly moving in and out of bass ports can cause an unwanted “chuffing” sound. While ABRs replace the mass of the air in the port tube with and equivalent mass diaphragm, they significantly reduce distortion and give a more stable sound with lower bass extension.
The result of this is that the clarity of the bass frequencies are equally matched with the detail of the ribbon tweeter – these frequencies extend right down to reach the fundamentals of orchestral instruments, creating our signature, breathtaking sound we are known for and as found in the original ESLs.
Beautifully presented with rounded top edges at the front and rear, each speaker cabinet uses a sandwich construction of alternate layers of MDF and high-density particleboard to reduce panel resonance to below the level of audibility. Aesthetically, the look is classically Quad yet subtly updated.
Specifications:
General Description: 3-way floorstanding speaker
Enclosure Type: ABR
Transducer Complement: 3-way
ABR: 125 mm x 3
Bass Driver: 125 mm Woven Kevlar Cone x 2
Midrange Driver: 100 mm Woven Kevlar Cone
Treble Driver: 12 x 45 mm True Ribbon
Sensitivity (2.83 V @ 1 m): 88 dB
Recommended Amplifier Power: 25 – 100 W
Peak SPL: 100 dB
Nominal Impedance: 6 Ω
Minimum Impedance: 3.5 Ω
Frequency Response (± 3dB): 44 Hz – 23 kHz
Bass Extension (- 6dB): 37 Hz
Crossover Frequency: 520 Hz & 3.9 kHz
Cabinet Volume: 47.0 litres
Dimensions: 870 (H) x 180 (W) x 300 (D) mm
Weight: 16.4 kg