Have you ever tried this combo or have this in your system? If you have, can you give me some details as to how it sounds? This would be used with PMC OB1i speakers. Any thoughts would be appreciated. Thanks in advance.
You can't go wrong with Quad amplification.
I have used Quad amplifiers exclusively now for forty two years.
The Quad current dumping amplifiers are superb and unique. There is no other amp in the world that has a circuit or configuration anything like that in the 909.
The current dumping amplifiers are one of the many strokes of pure genius by the late Peter Walker OBE, the founder of Quad.
The end result is a highly efficient amplifier, that performs as a class A amplifier with none of the draw backs.
They are a smooth effortless amplifier, guaranteed to be stable under all loads. They do not care what the phase angles are they just grin and bear it and perform with smooth effortless sound within their power range.
The true mark of genius is to reduce part count and reduce a concept to beautiful simplicity. The part count is lower than for any amplifier I am aware of at this power and specification.
There are no internal adjustments. Any part can go at least 30% out of spec, without affecting performance, due to the elegant feed forward self correcting design. So a long trouble free life form these designs is to be expected and that has been my experience. I own five 909 amps. I have lost count of the number of 405s I have in various iterations. I have had a couple of 303 amps, these are not current dumpers, for over 40 years now and have never had occasion to open the cases. They have a vast number of hours on them and currently are biamping a set of my speakers at our town home in the Twin Cities.
The Quad 909 will not care what speakers you have. you Can expect optimal performance from any speaker you choose.
I have not had a Quad 99 pre amp though my hands. I have three or four 33 preamps, two Quad 34 pre amps and a 44 preamp. I also have a Quad 22 tube pre amp I bought in 1965.
I have no reason to suspect that the Quad 99 is anything other than satisfactory, although that was designed after Peter's retirement.
Here are pictures of my 909 amps.
The three 909s on the left are triamping my left and right mains. The one on the right is biamping the center speakers.
On of the 405-2s are powering the surrounds, and the other two 405-2s biamping the rear backs.
The Quad preamps in the turntable case, from left to right, Quad 22, Quad 44 and Quad 34.
Quad FM 4, Quad 34 and Quad 909 in my downstairs system.
Here is a look inside a Quad 909.
You are looking at one power amp board of a 909, note the very low part count. The six output devices are either side. They are driven underrated for long life and these amps stay cool at high power. The output devices can be biased well towards class B, so efficiency is high and they stay nice and cool. The output stage has to provide the muscle, and does not have to be highly refined. A feed forward error correction is applied from a low power but very good class A amp. Peter showed mathematically and by measurement that the performance is entirely determined by the class A amp and not the six dumpers. Just brilliant!
I think the Quad 909 is the best domestic power amp available in its power class. I'm of the view that if you can afford Quad amplification, you should use it. I can recommend the Quad 909 without reservation.
I have only ever heard one pair of PMC speakers in a mastering studio in the Twin Cities and they are superb.
