Hi there -
Wondering if there are any of these out there that anyone has built, and the quality has met expectations? I expect that most available kits will come from China (which is OK with me).
405's dont come up often in NZ, I see a few kits on eprey, and wonder if there are certain ones better than others?
Wondering if there are any of these out there that anyone has built, and the quality has met expectations? I expect that most available kits will come from China (which is OK with me).
405's dont come up often in NZ, I see a few kits on eprey, and wonder if there are certain ones better than others?
Your choice should be about the format of your project. i.e. whether you want a 405 replica with original case style and build appearance where the PCBs are drop-in replacements for the original (you can even buy complete, working 405 copies from China) - or any cheap board kit with suitable, current style semis, components and power supply might satisfy one's curiosity.
The 405 and similar were designed with standard grade parts quality in mind so apart from a couple of early blunders with PCBs, a poorly documented earth wire link on the board and wrong type of ferrite core, the long running (>12 years IIRC) kits and boards you find on many platform seller sites, are fine for evaluation but they don't fit the original, odd-shaped 405 heatsink brackets. Instead, most are simplified to bolt on a typical, flat heatsink bracket or flange. There are more expensive PCB kits as mentioned, that do fit the brackets.
It may not be obvious but the 100WPC means a large and heavy E-I type transformer and some folk are obsessive about its manufacturing quality and amount of iron, to the point of having custom made versions built to Quad's spec. Maybe first up, you want to search and read a few build threads where these issues emerge, before diving in at the deep end. Inductors supplied in the cheapest kits could well be questionable too but it's not difficult to source your own through recognized Quad fansites. 'Not much more to worry about that hasn't already been discussed here, several times over though.
The 405 and similar were designed with standard grade parts quality in mind so apart from a couple of early blunders with PCBs, a poorly documented earth wire link on the board and wrong type of ferrite core, the long running (>12 years IIRC) kits and boards you find on many platform seller sites, are fine for evaluation but they don't fit the original, odd-shaped 405 heatsink brackets. Instead, most are simplified to bolt on a typical, flat heatsink bracket or flange. There are more expensive PCB kits as mentioned, that do fit the brackets.
It may not be obvious but the 100WPC means a large and heavy E-I type transformer and some folk are obsessive about its manufacturing quality and amount of iron, to the point of having custom made versions built to Quad's spec. Maybe first up, you want to search and read a few build threads where these issues emerge, before diving in at the deep end. Inductors supplied in the cheapest kits could well be questionable too but it's not difficult to source your own through recognized Quad fansites. 'Not much more to worry about that hasn't already been discussed here, several times over though.
https://liquidaudio.com.au/quad-405-2-power-amplifier-restoration/
https://www.aliexpress.com/item/1005002964322909.html
No, I have not bought any of those.
But Brzhifi make their own enclosures as well as electronics.
We had stuff from them before which are OK.
Just don't expect miracle. You get what you pay for.
A second hand 405 will easily set you back between 200~500USD.
And then your restoration cost starts.
Just info, NOT recommendation.
Patrick
https://www.aliexpress.com/item/1005002964322909.html
No, I have not bought any of those.
But Brzhifi make their own enclosures as well as electronics.
We had stuff from them before which are OK.
Just don't expect miracle. You get what you pay for.
A second hand 405 will easily set you back between 200~500USD.
And then your restoration cost starts.
Just info, NOT recommendation.
Patrick
About £70 shipping costs from the uk for a proper Quad one and plentiful to buy on the s/h market
It's not a 405, but a design that's evolved from the 405 using the current feed forward error correction, modern components, and, yes, mosfets. There's a (pdf) document that explains. Not my work, I'm just an interested bystander...
I have bought LJM's clone of 405 from doukmall ebay page, and I'm very pleased with parts and PCB quality. Theres two versions (that I know of), one with TO3 outputs and TO3P (some claim they are 405-2 version )... I bought 'former' one... also, clones are one of earlier version of amplifier, so it is advisable to go and see keith snooke or bernd ludwigs pages on how to upgrade circuit, I myself did keith's upgrades. oh, and for the end, with this ebay kit you buy only amplifier PCB+ and aluminum T adapter... chassis tranny and other hardware you need to provide yourself...