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Techno Commander
30-01-2011, 14:18
My girlfriend has a complete set of Quad II, 22 and FM tuner. She is considering having the power amps electronically "restored". Probably a full recap, rewire and possibly changing the resistors and connectors as well. This would not be a DIY job, but a professional refurb (looks towards Anthony :)). Cosmetically, they are in very good condition and dont require anything apart from a good clean.

Her dilema concerns the preamp and tuner. Is it worth having the preamp refurbed as well? The tuner doesnt get used very much and her choices are to spend money on the pre amp to keep everything as a set. Or sell the pre and tuner and invest the money from them along with what she would spend on the pre amp and buy something better?

hifi_dave
30-01-2011, 14:34
The pre isn't up to much sonically and there's not a lot you can do with it as it is a mass of wiring and switches. Back when Quad II's were a reasonable price, we used to re-furb them and partner with a Croft pre-amp.

Having said that, it is nice to have a complete set of quad installed in a cabinet. Maybe not the last word in fidelity but a nice thing to use, touch and admire.

Rare Bird
30-01-2011, 15:20
I would keep the pre & Tuner for completeness as dave says..If they were mine i'd opt for gutting the power amps but only rebuild with carefully selected parts ie: Carbon resistors, paper in oils etc as i'd want to restore that certain originality of sound.It's not gonna cost you an arm or a leg as there's only half dozen caps & around a dozen resistors per amp so you could afford the best.

Jonboy
30-01-2011, 17:13
If Anthony did not want to do them or you are not happy about posting them you could drop them in to me i can get them done for you we are only about 1 hour away from you, they will be done very reasonably by someone who is very well known for valve rebuilding, any caps you want can be fitted, back to standard or somewhere in the middle, he can tell at a glance what needs to be done and knows what works with them the best, the pre amps are nothing special but probably worth keeping together,

hifi_dave
30-01-2011, 21:39
Having experienced many mod'd, repaired, uprated and improved Quad II amps, I would suggest you keep them as original as you possibly can, only replacing any faulty components with as like parts as you can get. I have heard some real horrors in which components had been replaced with modern, high quality parts and totally ruined the balanced, fluid sound of the Quads.

Even worse - back in the 80's, there was a fashion to 'uprate' components to squeeze 20 watts or so from these lovely amps. The result was over-heating and often, burnt out transformers.

Quad knew what they were doing.

Barry
30-01-2011, 21:54
Having experienced many mod'd, repaired, uprated and improved Quad II amps, I would suggest you keep them as original as you possibly can, only replacing any faulty components with as like parts as you can get. I have heard some real horrors in which components had been replaced with modern, high quality parts and totally ruined the balanced, fluid sound of the Quads.

Even worse - back in the 80's, there was a fashion to 'uprate' components to squeeze 20 watts or so from these lovely amps. The result was over-heating and often, burnt out transformers.

Quad knew what they were doing.

Agreed! Two of the components that are often replaced in old Quad IIs are the coupling capacitors to the grids of the KT66s. These were made by Hunts, and are not regarded as being of particularly good quality.

What 'upgraders' do not understand is that these tubular metal-clad capacitors were mounted against the (earthed) metal chassis. The stray coupling capacitance between these capacitors and the chassis was known about and taken into account by Peter Walker during the design.

Upgrade at your peril!

Regards

Techno Commander
30-01-2011, 22:05
Thank you Jon. we will bear that in mind.

We would want the work to be done sympathetically. I would rather have all capacitors replaced as they are likely to be well out of spec. However I would prefer them to be replaced with appropriate components, as opposed to "bling" alternatives. I dont go with the idea of trying to squeeze more power out of these. Apart from anything else, trashing a set of GEC KT66s wouldnt be good.

These amps are 50 years old and there is no reason why they shouldnt do another 50 years if given a little TLC. :)

Jonboy
30-01-2011, 22:14
Quad knew what they were doing.

thats why i suggest the man i'm talking about, he likes to keep things as they were intended and just replace what needs doing, he is not a big fan of so called upgraders either of these and some other classic amps