Audio Database
Model878
Commentary

A stereo power amplifier that pursues balance theory.

The Model878 supports balanced connections and provides better reproducibility than conventional unbalanced connections.

The interior is completely independent on the left and right.

By replacing the plug-in type circuit board, you can use it in three different ways : stereo amplifier, monaural amplifier, or active speaker.
When using a stereo amplifier, the two monaural amplifiers in the main unit amplify each of the L and R channels. When using a monaural power amplifier, a bridge connection allows two monaural amplifiers to be driven in one block for high power output.

The active speaker configuration uses an optional crossover module (sold separately).
A crossover circuit board allows you to switch between two monaural amplifiers, one with an integrated high-pass filter and the other with an integrated low-pass filter. The circuit board has a 6 dB per octave attenuation and allows you to specify the crossover frequency.

Model Rating
Type Stereo power amplifier
Effective power Stereo : 100W + 100W (4 Ω)
Mono : 272W (4 Ω)
Peak power Stereo : 200W + 200W (4 Ω)
Mono : 544W (4 Ω)
Input sensitivity 880 mV (both balanced and unbalanced)
Input impedance 10k Ω (both balanced and unbalanced connection)
Signal-to-noise ratio (to 5W) -96dB with balanced connections
-87dB (unbalanced connection)
Frequency characteristic 5 hz to 170 khz -3dB
Total harmonic distortion factor 0.009%(5W)
Cross modulation distortion factor 0.04%(5W)
Rise time 2.8 μ sec
Slew rate 18 v / μ sec
Damping factor 400
External dimensions Width 510x Height 98x Depth 305 mm
Weight -
Sold Separately Crossover module