Development of the PV1
The Problem The holy grail of subwoofer design is deep and clean bass from a near-invisible box. The immediate problem that arises is that reduced box size both curtails bass extension and increases pressure on the enclosure wall and driver diaphragm. Many small subwoofers are unable to reproduce sufficiently extended bass and suffer from considerable cabinet coloration, often resulting in bass that is uneven and dissociated from the midrange and treble.
To illustrate this, there are two analogies that we can apply. The first is the soap bubble. An undisturbed bubble assumes a spherical shape because the pressure difference inside and out is perfectly balanced by the only force the bubble can sustain - surface tension that is entirely in the curved plane of the skin. The second important analogy is found in the architecture of Antonio Gaudi.
These effects are related to the ratio of the sound The problems inherent to small subwoofers are often wavelength to the dimensions of the enclosure. The compounded further by the industrial designer’s desire to resulting pressure and force gradients allowed the reintroduction of bending forces on the walls of the sphere, which raised the level of radiated sound and coloration. Going back to our soap bubble analogy it shave off centimetres here and there.
A secondary consequence of the use of twin opposing Naturally, the driver must be capable of handling this drivers is the inherently balanced kinetic nature of the power. The large magnet structure aids control of the device. It is well known that the reproduction of bass motion of the diaphragm and forms an effective heat with correct dynamics requires a firm, solid foundation – sink for the voice coil, which, at 30mm long, allows sometimes referred to as a mechanical ground.
low-pass filter 80Hz dB EQ = i EQ = ii EQ = iii PV1 - frequency response 100 10 % 1 Bandpass output level 90dB at 1m 0.1 0.01 PV1 - total harmonic distortion -20 dB The vibration levels of the PV1 (red) are -30 compared with those of a conventional -40 subwoofer (blue) of similar bandwidth, -50 output capability and drive unit radiating -60 area, but using a single 250mm driver in a heavily braced wooden cabinet.
Technical features Pressure vessel enclosure 500W ICEpower® amplifier Switch mode power supply Description Active closed-box subwoofer system Drive unit 2x 200mm (8 in) dia mica / aluminium diaphragm long-throw Frequency range -6dB at 18Hz and 40/140Hz adjustable (EQ at i) Frequency response ±3dB 21Hz – 31/110Hz adjustable (EQ at i) Amplifier Power output: Rated power consumption: Input impedance: Signal / noise: Functions: Inputs: Outputs: 500W 110W (105W - 100V version) 100kohms >90dB Volume level Low-p
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