【前後級】Simaudio 740P前級、860A後級

[Leo Yeh]

740P前級與860A為Simaudio最新一代的前後級，也是立體聲前後級的次旗艦 (旗艦是850P跟870A，880M是單聲道後級)
在外觀上仍保持的該廠一樣的傳統，並無太大的更動
但是內部已經有許多的進化

[Leo Yeh]

Moon 860A 內部大公開

200 watts into 8Ω and 400 watts into 4Ω
zero global feedback
Custom proprietary toroidal transformer

http://www.simaudio.com/moon860A.htm






















The Evolution of power amplification ...

The MOON 860A Power Amplifier is a balanced differential dual-mono design that effortlessly outputs 200 watts into 8Ω and 400 watts into 4Ω. Transparency and soundstage are exceptional, despite this amplifier's high power rating. Ultimately, the 860A will mate seamlessly with any loudspeaker allowing it to reach its full sonic potential, regardless of its load.

Several in-house developed advancements allow the MOON 860A to perform with both accuracy and grain-free character; These include (i) MOON output transistors, specifically designed for use in our amplifiers, providing tighter and more visceral bass performance, as well as unprecedented linearity thoughout the entire frequency spectrum; and (ii) our advanced "zero global feedback" circuit, commonly referred to as Lynx.

Of course, both RS-232 and 12 Volt triggers for custom-install environments are included as well as a plethora of user selectable cosmetic options that are available at the time of purchase.

Significant Design Features:

· Full unsolicited RS-232 bidirectional feedback
· Lynx circuitry which is a "no overall feedback" design resulting in genuine real-time amplification,
a more accurate musical reproduction with respect to tonality, virtually non-existent IMD and the
elimination of common phase errors resulting from feedback
· Precision matched and fully decoupled proprietary MOON Bipolar output transistors with
unprecedented gain linearity resulting in improved bass response and even more accurate
sonic reproduction
· Custom proprietary toroidal transformer design with lower magnetic, electrical and thermal
loss, yielding an improved power transfer and lower regulation factor. The result is increased
current speed and better dynamics
· An oversized power supply
· 12 Volt trigger input/output for remote operation
· "Class A" output to 5 watts for greater efficiency
· A high damping factor yielding superior musical dynamics, improved signal speed and refined
timbre accuracy
· A very short capacitor-free signal path for a faster transient response
· Stable to any known speaker impedance
· 4-Layer PCB’s with pure copper tracings for a much shorter signal path; This results in
greater sonic accuracy and a dramatically improved signal-to-noise ratio
· Ultra rigid chassis construction to minimize the effects of external vibrations
· Accurate matching of the very finest quality electronic components in a symmetrical circuit design
· Designed to be powered up at all times for optimal performance
· Low operating temperature for a longer than normal life expectancy.

[Leo Yeh]

Moon 740P 內部大公開

全平衡雙單聲道設計
http://www.simaudio.com/moon740P.htm

















Significant Design Features:

· Full unsolicited RS-232 bidirectional feedback
· A dual-mono oversized power supply using 2 toroidal transformers in conjunction with 5 stages
of DC voltage regulation and extensive choke filtering
·4 stages of our newly developed M-LoVo (MOON Low Voltage) DC regulation circuit; a highly
sophisticated circuit made up of a clever combination of IC’s and discrete parts that is virtually
free of noise, yielding an exceptionally fast, precise, and stable DC voltage. The result is a
power supply with a virtually unmeasureable noise floor
· SimLink controller port for 2-way communications with other compatible MOON components
· M-eVOL2 volume control circuit using MDAC’s (operating in a current steering R-2R configuration)
which alter the audio signal’s amplitude yielding no sonic degradation of the signal, regardless
of the selected volume setting
· 530 individual volume steps in 1dB and 0.1dB increments
· M-Lock for “user selectable” maximum volume setting lock-out for each line input
· Power supply voltage regulation includes i²DCf (Independent Inductive DC Filtering); There is
one inductor dedicated to each integrated circuit type component (DAC, Op-Amp, etc.) in the
audio circuit’s signal path - 24 stages in all
· “Gain offset” for each individual line input with a ±10dB range
· Each line input is fully configurable to be “home-theater ready”, where the gain section of the
740P is bypassed
· 4-Layer PCB’s with pure copper tracings for a much shorter signal path; This results in
greater sonic accuracy and a dramatically improved signal-to-noise ratio
· 12 Volt trigger output for remote operation
· Ultra rigid chassis construction to minimize the effects of external vibrations
· Accurate matching of the very finest quality electronic components in a symmetrical circuit design
· Improved reliabilty through the elimination of moving parts
· Includes FRM-3 all-aluminum back-lit remote control.

[Leo Yeh]