The Koetsu cartridges in the Platinum series are made from mineral rock. The versions vary according to the type of stone used. Each cartridge is made from a block of rock selected by a skilled craftsman. For this cartridge, each block of coralstone is chosen for its natural aesthetic and quality. The rock is cut into the final shape and carefully polished for a glossy finish. This process requires great expertise. It takes several hours so as not to crack the stone.
The electrical components are meticulously assembled to obtain a perfect magnetic balance and, hence, a finer, smoother and clearer sound quality. The coils are different from other models as they use a high purity (6N) silver plated copper compound. The magnetic system uses strong magnets: 'Platinum Magnets' that are made of a platinum alloy. This hypersensitive motor reacts to the slightest movement of the stylus in the groove. This results in a subtle sound quality and unrivalled precision. The stylus is conventionally fitted to a boron cantilever.
The Koetsu Coralstone Platinum has a relatively low output level, which means that it should ideally be used with a preamplifier of the same high quality. Franck
Type: Low output MC
Magnet: Platinum Magnet
Output: 0.4 mV
Frequency response: 20 Hz-100 Khz
Channel separation: 25 db
Internal impedance: 5 Ohms
Channel balance: 0.5 dB at 1 khz
Load resistance: 30 Ohms
Weight: 8.9 g
Compliance: 5 x 10-6cm/dyn at 100 hz