The QSP Stereo Power Amplifier is a by-product of the famed Quad 909 Stereo. This product was designed in keeping with the traditional built of QUAD Power Amplifiers, but is right up with the latest technology and the finest audiophile components available. With 140W per channel into an 8 ohm load, and plenty more into lower impedances ensures that there is ample power into a wide range of speakers, including the QUAD ESL range.
Current Dumping - The QSP Amplifier incorporates QUAD's patented current dumping technology developed by QUAD's founder Peter Walker, and is one of the finest audio amplifiers available. One of the few truly innovative amplifier topologies, it is essentially a combination of two amplifiers to give the best of both in each channel. The current dumping circuit like the Quad QSP Amplifier consists of a very high quality class A low-power amp which provides the details of the signal, while a high-power current dumping section provides the grip to keep the speakers under control. These two amplifier circuits are combined with a precision network to perfectly impose the finesse of the class A output onto the power of the current dumper.
This technology eliminates the problems of crossover distortion, quiescent current adjustment, thermal tracking and transistor matching. There are no internal adjustments or alignments and the choice of power transistor types is less restrictive.
|Power Output||140W into 8Ω (<0.01% THD at 1kHz)|
|Total Harmonic||<0.004% (100W at 1kHz)|
|Distortion (THD)||<0.025% (100W at 20Hz - 20kHz)|
|Output Impedance||0.05Ω in parallel with 1.5mH|
|Frequency Response||-1.0dB at 1Hz and 55kHz, ref. 1kHz|
|Power Response||-0.25dB at 20Hz and 20kHz, ref. 1kHz|
|Input Sensitivity||760mV (RCA line input)|
|Input Impedance||10kΩ (balanced)|
|Crosstalk||-90dB at 1kHz (input loaded with 600Ω)|
|Signal-to-Noise Ratio (ref. 140 Watts)||108dB (20kHz measurement bandwidth)|
|Stability||Unconditional with any load and input|
|Standard Accessories||Power cord, User manual, Warranty Card, Ampbus cable|
|Dimensions (W × H × D)||328 × 149 × 270 (mm)|