C225 Low Frequency Driver with Short-coil long-gap motor design

C225 stands unique amongst bass drivers, designed as the bottom end power-house of our flagship loudspeaker; the GIYA G1. C225 shares many family resemblances with the C125 including the highly aligned radial struts used in the chassis construction.

Vivid Audio C225 Low Frequency Driver with Short-coil long-gap motor design From its inception, Giya was to be a four way system so the lowest frequency band could be handled by a driver optimised for that purpose. It is all too easy when designing a bass driver, to put all the effort into a superlative motor system only to use an off-the-shelf pulp cone and heavy rubber surround ignoring the effect these will have on the upper frequencies. Vivid Audio designs have always placed great store in the importance of maintaining good out-of-band performance and, while having a generous piston diameter of 225mm, the all aluminium alloy diaphragm construction extends the area of pistonic operation to beyond 2kHz thereby maintaining a comfortable margin between crossover and the first break-up frequencies ensuring absolute purity in the pass-band.

C225 shares many family resemblances with the C125 including the highly aligned radial struts used in the chassis construction. These twelve elements, which present the slenderest section and smallest obstruction to the moving air, nevertheless offer a substantial area in the orthogonal direction with which to dissipate heat, with much of that area located where it will have the maximum benefit, along the full length of the central hub which houses the magnet structure.

Maintaining the Vivid philosophy of underhung motor design, the C225 uses a 12mm long coil in a 35mm long magnetic gap which gives 23mm of linear travel. A mechanical travel capability of 54mm further ensures the capacity to move massive amounts of air. Moving large amounts of air takes substantial amounts of power and a 75mm diameter aluminium ribbon voice coil permits high power transfer while keeping the coil temperature down so minimising power compression effects. Having such a long gap is great for linear travel but requires a proportionately large amount of total flux. This in turn requires all the available area of the pole to be used for flux guidance so a central vent hole is undesirable, but, thanks to the used of the highly perforated coil former pioneered in the C125, the air within the former can still escape with little resistance and no problem resonance.

Vivid Audio Super Flux Magnet Technology Racing Car like Performance

Despite the exceptional gap length, a flux of 1Tesla is maintained evenly along its full extents through the use radial magnet technology. This highly efficient system creates an exceptional level of force from the input current. The result is a driver which couples this tremendous level of shove with a low moving mass of 50g to deliver a truly racing car like performance for the ultimate delivery of fast articulate bass. On its own, however, such a taut driver would give a very bright balance and only really comes into its own when coupled with its computer optimised filter network, the two working together as a unified system rather than separate elements designed in isolation.

Find out more about Super Flux Magnet technology

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