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Counterpoint sa-3.1 with a quad 909, Will it work ?

The Finisher

The Finisher

Must have shot a robin
Me again!
So I’ve just bought a quad 909 power amp and would like to know if my counterpoint tube preamp will work with it or not because of any impedance issues .
I do have the counterpoint up for sale but I’ll keep it if it’ll work ok with the ss quad .
 
A vacuum tubes preamp is often a good match with a solid state amplifier so I would definitely give it a try.
Just make sure the volume knob is at the minimum when you will put your first favorite song, in case the gain is not at the right value for the Quad.
 
I always had good experiences with tube preamp and ss amp.
It's my favourite combo.
Maybe not the best match aesthetically (a power amp with the same footprint as the Counterpoint would have been better).
 
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I have no idea about that , I can’t find a schematic either.
 
I was and maybe still am looking at a counterpoint power amp on eBay ( in Spain) but the reviews are not great, having said that reviews are a nightmare
 
I loved the counterpoint transport and dac I owned. I’d be curious to hear their amps. I’d bet they’d be pretty good.
 
Any pre amp will work with any power amp... how well is the issue!

It does not have a cathode follower and has zero feedback. I would expect pretty excessive gain and relatively high distortion. It should be just about OK with the Quad but it's not ideal.
 
Yes I think the gain will be an issue , I’ll wait to try it once I get the quad then if not I’ll wait for the counterpoint to sell.
 
The Counterpoint uses an unusual bias scheme of contact potential biasing, sometimes wrongly called leaky grid biasing... Quite odd.... and not really a very good idea as any trace of "softness" to the vacuum and it's likely to go into runaway. In the 5.1 they stick with grounded cathodes but use full on fixed biasing, as in many valve power amps. They're determined to keep the cathode grounded even if they have to go to these lengths it seems. This method is better, safer and more predictable but for optimum results it may need re-biasing from time to time as the valve wears.
Why are they determined to ground the cathodes? It's very unusual.... I can only guess that they liked the way it sounded in subjective tests:)

It was common in the very early days of valves when a grid battery was commonly used for just this purpose of fixed biasing. There would usually have been a filament battery (often a 2V lead acid accumulator that would be taken to a garage or chemists shop to be recharged) and an HT dry battery of 90V or 120V. Even after mains powering became more common for early radio sets the grid battery stayed for quite a while as it was an easy way of getting hum free grid bias and the battery could last for virtually its shelf life.
 
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