Lab.gruppen C Series 5:4X - Manual (Page 9)

C Series C 20:8X, C 10:8X, C 10:4X and C 5:4X Operation Manual rev. 1.1.4
Welcome
2
2.2 Main Features
Your new C Series amplifier incorporates a number of sophisticated technologies – many of them proprietary to
Lab.gruppen – that are provided to ensure the best possible performance and many years of reliable operation.
Familiarizing yourself with these technologies will prove invaluable in setting up and optimizing your loudspeaker
system.
2.2.1 Class D output stage and universal power supply with PFC
All C…X amplifiers employ a unique Class D output stage that is ideally matched to the lower power outputs of
these amplifiers. The original C Series amplifiers, with power output up to 8800 watts total, require use of Lab.
gruppen’s patented Class TD in order to maintain sonic purity and high efficiency; however, at the lower power
levels of the C…X models, Lab.gruppen’s advanced Class D circuit offers the same performance benefits in a
more cost effective manner.
C…X amplifiers also incorporate a newly developed universal switching power supply which accepts any
voltage from 100-240 V (+/- 10%) @ 50 or 60 Hz. A Power Factor Correction circuit stabilizes current draw
under changing conditions.
2.2.2 Amplifier gain
For greater flexibility in system integration, C...X amplifiers allow gain adjustment from +29 to +38 dB in 3 dB
steps. If the input signal is weak, the gain can be boosted to maintain maximum power output while avoiding a
poor signal-to-noise ratio. This gain adjustment feature makes it easier to achieve an optimal balance between
headroom and noise floor.
2.2.3 Voltage Peak Limiter (VPL)
The Voltage Peak Limiter (VPL) feature allows user adjustments that determine maximum voltage output, thus
matching the amplifier to the connected speaker load. Whether the connected load is low-impedance (2 to 16
ohms) or high-impedance (70 Vrms / 100 V peak), the VPL feature can be set to ensure that neither tempera-
ture nor current limitations are exceeded before reaching the desired voltage threshold.
2.2.4 Protection and performance optimization
Appropriate and reliable power amplification is vital to any audio system. Inadequate or faulty power
amplification could cause damage to the loudspeakers, or in some cases to the power amplifiers themselves.
To prevent any damage or costly service interruptions, C Series amplifiers offer advanced features to protect
both internal circuits and any connected loads. These features even protect the mains fuse that, in extreme
cases, could be overloaded.
Following are short descriptions of standard built-in C Series protection features: