IsoTek, AV & Home Automation ALPHA LITE

To ensure the best possible sound quality, the mains supply must meet two basic requirements: a clean 50 Hz sine wave provided by a source with the lowest possible impedance, and the absence of high-frequency noise. Low impedance ensures an almost constant voltage, regardless of how much power is being consumed in the vicinity. In practice, fluctuations of around
5% can typically be expected. The very low impedance of the mains supply, which is well below 1 ohm at 50 Hz, is not maintained when affected by radio frequencies (> 50 ohms > 100 kHz), and it acts like an antenna that actively attracts interference. IsoTek's mains filter circuits are designed to reduce impedance, operate reliably, and work well into the audio frequency band. This is achieved not only through sound electrical engineering, but also by reliably meeting electrical safety requirements.

Overvoltage and voltage spikes in the power supply generally pose a risk to any electrical device, but especially to the sensitive components in hi-fi and home cinema systems. Voltage spikes or overvoltage occur when an electrical charge builds up somewhere in the mains supply—for example, due to a lightning strike or the switching on and off of high-power devices such as lift motors or air conditioners. The resulting changes in the magnetic or electric fields around their high-voltage cables can cause voltage spikes in nearby cables. IsoTek's protection system uses multiple varistors (VDRs = voltage-dependent resistors), providing protection against current surges of up to more than 100,000 A. Depending on the magnitude of the overvoltage or voltage spike, the system activates in rapid, sequential stages, greatly extending its protection when needed, almost instantaneously. The protection circuit has two main functions: to protect itself and to respond rapidly and in stages when a problem occurs. The protection circuit also safeguards the filter stages against possible damage, while the filters themselves provide additional support when irregularities arise. Unlike many other protection systems, IsoTek components not only provide optimal protection, but also have a positive effect on sound quality. Studies suggest that voltage spikes occur quite frequently, especially in the range of 1,000 to 6,000 V. It is reasonable to assume that most protection systems are not comprehensive in their effect and are also likely to compromise sound quality.