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Quad 909

Stereo Power Amplifier (2004)

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Quad 909


The Quad 909 is a two channel power amplifier using current dumping technology.

It weighs approximately 12kg and is built to be robust.

The performance of the 909 amplifier is as accurate as it is possible to achieve by careful design, selection of components and rigorous test procedures.

The unit has no controls other than a power switch (which is normally left on) and may be mounted out of sight in a cabinet or other convenient location.

To keep BUS connections simple you can place the unit below the 99 preamplifier.

Power amplifiers can be placed alongside or out of sight using a long 99 AMPBUS cable.

The amplifier is full compatible with the ESL-63, ESL-988 and ESL-989 loudspeakers but it should not be used with the earlier model ESL which could be damaged by signal peaks unless a protection circuit is fitted in the loudspeaker.


Power output: 140 watts per channel into 8Ω (stereo)

Frequency response: 13Hz to 40kHz

Total harmonic distortion: 0.01%

Input sensitivity: 0.775V

Signal to noise ratio: 108dB

Speaker load impedance: 4Ω (minimum)

Dimensions: 321 x 140 x 240mm

Weight: 12kg


Related Catalogues

99 Series

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Reviewed Oct 06th, 2015 by colin44ct357

Reworked a 909, standard 1200watts of to3 tranis per channel and 2 x 16000uf psu caps per channel. I drove it directly from a cda in my br player, at 25% it rearranged the ornaments in my home, what a beautie!
The deep pure british tone rules, saw some nasty comments on the net...The clinical synthetic audio systems of today dont compare, retro rules...Sound is life!



This website is not affiliated with or sponsored by Quad. To purchase 909 spares or accessories, please contact the company via their website or visit an authorised retailer.