repairing a quad 303

[Thunderchild]

I've got an old quad 303 power amp that needs new smoother and output condensers, I've contacted quad and they say they can supply them, but are these going to be like the originals or just modern condensers of the same value that I could buy elsewhere at the same price ?

has anyone else worked on quads and dealt with quad for replacements before ?

 

[Nigel Goodwin]

I've got an old quad 303 power amp that needs new smoother and output condensers, I've contacted quad and they say they can supply them, but are these going to be like the originals or just modern condensers of the same value that I could buy elsewhere at the same price ?

has anyone else worked on quads and dealt with quad for replacements before ?

Quad have long since gone, the name is now used by some less reputable company - and the service isn't what it was. Last I heard they were totally unhelpful.

Just buy replacement capacitors from anywhere of the same value, there's nothing special about them.

There was an official modification (decades back) to replace the smoothers with new ones fitted upside down, and wired down the outside. This was because the originals leak and corrode the PCB's.

If you google, there's LOT'S and LOT'S out there about them, including performance mods and even replacement PCB's to make your own ampliifers.

Bear in mind, while 303's were good amplifiers, it was a LONG time ago, and they have been surpassed many times since.

 

[Thunderchild]

I wanted to keep it all as original as possible so as to resell it as a working quad 303, can original psu board be bought ? or are they just mods ?

 

[Nigel Goodwin]

I wanted to keep it all as original as possible so as to resell it as a working quad 303, can original psu board be bought ? or are they just mods ?

I doubt you could buy original boards now, if you ever could?.

Why do you need a new board?.

 

[Thunderchild]

it has signs of burning under one resistor, my dad is thinking it might be easier to just replace it, I'd just get some replacement caps and take it from there

 

[Nigel Goodwin]

it has signs of burning under one resistor, my dad is thinking it might be easier to just replace it, I'd just get some replacement caps and take it from there

No need to replace the board, on an amp that old there's likely to be some discolouring.

You might find this (one of many links) helpful

https://www.electro-tech-online.com/custompdfs/2009/07/site27_20081122163115_1_303_service_data.pdf

 

[Thunderchild]

thanks that is useful info

 

[Nigel Goodwin]

thanks that is useful info

I've repaired various items of Quad gear over the years, it's nice stuff.

I've think I've mentioned this before, but back in the 70's I used to help run a music club - a band played there one night, and they had something like 13 Quad 303's they used as PA - and they had been given them