soulution
nature of sound
Page 4
2Technical highlights
2.1 Philosophy
The ideal amplifier is perfectly load stable, 100% level and phase accurate, and
has no long signal paths. It should not use tricks like over amplification and very
high negative feedback to achieve good results in the lab but poor sonic perfor-
mance in the listening room. The stereoamplifier 711 combines extreme speed with
an ultra wide bandwidth (1MHz/-3dB) and a high current capability far beyond that
of valves and output transformers. A unique and sophisticated circuit design opens
up sonic qualities once considered incompatible: precision, velocity, stability and
power.
2.2 Layout
Throughout, the stereoamplifier 711 is designed as a consistent dual-mono layout.
Both left and right channels feature identical audio amplifiers, each with its own
high efficiency power supply. The layout is optimized towards shortest signal paths.
For minimal losses the stereoamplifier 711 has massive copper rails for all high cur-
rent signal paths.
2.3 Amplification
From the input the stereoamplifier 711 first buffers the music signal. A high per-
formance correction amplifier is then used to capture and correct any deviations in
the signal, very quickly and very precisely. Ultra wideband amplification using no
feedback loops follows, a less than 10 nanosecond transit time and level accuracy
to within 0.1dB ensuring signal purity. The whole is housed within a sealed module,
maintaining a common temperature across all stages to further guarantee precision.
The output stage comprises 14 power transistors per channel, all mounted onto a
massive copper rail which is temperature controlled for a constant quiescent cur-
rent. The 711‘s impressive low level signal handling is reflected in its raw power de-
livery. Current levels of 60A and more are readily attainable.
2.4 Power supply
The supply of the amplifier section is based on modern switched mode power sup-
plies. Four modules with 600VA each optimized for audio application combined
with audiophile capacitors (>1’000’000 microFarad) provide enough power reserves
even for the most demanding music signals. Circuitry that does not process audio
signals should not be able to influence them. That’s why we use no less than 5 ded-
icated power supplies for the ancillary stages.
