the amp under question is a Quad 303
1) i take as a fact that anyone claims that this amplifier might play properly is a complete non audio related person ...On second thought it might as well be someone with extreme or unexplainable feeling of romance for cans like that . so his opinion cannot be valid in no possible way .
2) i take also as a fact that on first hand the designer had absolutely no relation with the production manager or the can designer .... then of course i take as a fact that in the can factory they produced the cans they didn't have scopes ... or even if they did it is most likely that they didn't know how to operate them
3) one may say that the can was unique when it comes to size and dimensions but other than that this cannot be called a HIFI amplifier and it seems that the target was a unique outline rather than a working amplifier .
I am pretty sure that there is no chance that they ""haven't seen """ seen or didn't notice or didn't know .A tragic example of arrogance is that actually they new but still produced the can ...
Secret lays on the wiring of the 303 where input +output +signal+plus rails +minus rails +ground +base cables +emitter cables +collector cables X times2 for left and right amplifier are tied all mixed and together producing all shorts of electrical interference phenomenon .
As about crosstalk injected from the wiring i could live with that ... as about channel separation ...might also as well .... But all this oscillation produced by the mixed wiring simply is out of any question .
The #1 thing you never do is to twist B-C-E wiring from a board to a transistor How about twisting altogether?
unbelievable !!!!
PS :
Cheerful joke for simulation people
""enjoy one more thing that your simulator cannot show you ""
enjoy pics
1) i take as a fact that anyone claims that this amplifier might play properly is a complete non audio related person ...On second thought it might as well be someone with extreme or unexplainable feeling of romance for cans like that . so his opinion cannot be valid in no possible way .
2) i take also as a fact that on first hand the designer had absolutely no relation with the production manager or the can designer .... then of course i take as a fact that in the can factory they produced the cans they didn't have scopes ... or even if they did it is most likely that they didn't know how to operate them
3) one may say that the can was unique when it comes to size and dimensions but other than that this cannot be called a HIFI amplifier and it seems that the target was a unique outline rather than a working amplifier .
I am pretty sure that there is no chance that they ""haven't seen """ seen or didn't notice or didn't know .A tragic example of arrogance is that actually they new but still produced the can ...
Secret lays on the wiring of the 303 where input +output +signal+plus rails +minus rails +ground +base cables +emitter cables +collector cables X times2 for left and right amplifier are tied all mixed and together producing all shorts of electrical interference phenomenon .
As about crosstalk injected from the wiring i could live with that ... as about channel separation ...might also as well .... But all this oscillation produced by the mixed wiring simply is out of any question .
The #1 thing you never do is to twist B-C-E wiring from a board to a transistor How about twisting altogether?
unbelievable !!!!
PS :
Cheerful joke for simulation people
""enjoy one more thing that your simulator cannot show you ""
enjoy pics
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Oh yes it does; the people who built this thing really knew what they were doing. Have you spotted the output is a triple yet? And it's stable too...
The amp even has a regulated supply, but that's only because Quad judged it the most reliable and best-value way to protect the power transistors.
The amp even has a regulated supply, but that's only because Quad judged it the most reliable and best-value way to protect the power transistors.
you can say as much as you like ...scopes never make mistakes when it comes to things like that ( things like that is not a question of opinion or choice ) things like that its simple electrical measures ...nothing else
( and by the way it doesn't look to me that a regulated power supply might provide some safety when its not needed in a low power single rail capacitor coupled amplifier on the contrary it could only provide a bit less modulation to the rest of the cables as long the power is regulated but nothing else )
( and by the way it doesn't look to me that a regulated power supply might provide some safety when its not needed in a low power single rail capacitor coupled amplifier on the contrary it could only provide a bit less modulation to the rest of the cables as long the power is regulated but nothing else )
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Lots of those things doing sterling service driving small nearfields in broadcast installations up and down the country.
They do just fine.
Bear in mind that that amplifier uses some very old (And thus low Ft, low beta parts), a little wire is just not the issue it would be with modern sand.
The one thing to change is that apalling mains input connector, nothing but trouble, but that is largely a historical artifact, the amp itself works ok, and just keeps on trucking, I have seen some that have been power on for at least ten years, stuck in the back of a bay frame with no attention, the things just work.
Sure, you would design something different these days, but the thing is by no means rubbish, especially given the available sand at the time.
Those PCBs need some care if doing work, they are old enough that the adhesion of the tracking is sometimes not everything you would like.
73, Dan.
They do just fine.
Bear in mind that that amplifier uses some very old (And thus low Ft, low beta parts), a little wire is just not the issue it would be with modern sand.
The one thing to change is that apalling mains input connector, nothing but trouble, but that is largely a historical artifact, the amp itself works ok, and just keeps on trucking, I have seen some that have been power on for at least ten years, stuck in the back of a bay frame with no attention, the things just work.
Sure, you would design something different these days, but the thing is by no means rubbish, especially given the available sand at the time.
Those PCBs need some care if doing work, they are old enough that the adhesion of the tracking is sometimes not everything you would like.
73, Dan.
I couldn't stand the sound of it, nor could I enjoy the utterly undynamic and bland sounding 33 preamp. Don't hate me, Its just my opinion, thats all. The 66 and 67 CDPs were really nice, the 606 and 909 power amps work well with many other associated pieces but the 99 preamp, thin and hollow.
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Good grief. It's a 1966 transistor amplifier design. Can it be bettered for measurements etc ? Yes, of course. But of its time it's really damn good. Leave it be - there's not much more performance hiding in there for the sake of being a smart alec and re-routing a few wires.
The 303 was one of the first really serious attempts to get a transistor amp to match or exceed valve technology. The slow devices available meant it could be built using loom techniques just like valve amps built along side it. Hardly surprising!
Try it into a suitably-period pair of speakers , say Tannoy dual-concentrics or the matching ESL57s; if all you want to do is listen to lots of music these things still deliver surprisingly well.
The 303 was one of the first really serious attempts to get a transistor amp to match or exceed valve technology. The slow devices available meant it could be built using loom techniques just like valve amps built along side it. Hardly surprising!
Try it into a suitably-period pair of speakers , say Tannoy dual-concentrics or the matching ESL57s; if all you want to do is listen to lots of music these things still deliver surprisingly well.
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