In the luxman M03 designer placed transistors on heatsink one by one, one N and one P.
That creates a mess on the pcb resulting copper flat bars installed for power distribution.
I understand that a practice like that will equalize tenperature better and probably in combination with the copper bars might also have equal or better rail distribution or equal draw of current between a number of transistors.
I expect that this will have some effect on the distortion figures of the amp, and i also expect that if the amp is pushed wilk behave better due to better and equal power distribution. That can also effect the sonic signature providing better kick for example or better drive abilty.
I think though from one hand that this type of diference will be marginal but on the other hand Japanese never did anything that is marginal
To proceed with a thing like that something waa important.
Opinions?
Am I missing something else here?
That creates a mess on the pcb resulting copper flat bars installed for power distribution.
I understand that a practice like that will equalize tenperature better and probably in combination with the copper bars might also have equal or better rail distribution or equal draw of current between a number of transistors.
I expect that this will have some effect on the distortion figures of the amp, and i also expect that if the amp is pushed wilk behave better due to better and equal power distribution. That can also effect the sonic signature providing better kick for example or better drive abilty.
I think though from one hand that this type of diference will be marginal but on the other hand Japanese never did anything that is marginal
To proceed with a thing like that something waa important.
Opinions?
Am I missing something else here?
It makes absolutely no difference upon where the power transistors are placed with performance.
Any extra/less capacitance/inductance that results in a difference not enough to measure.
My advice is don't use assumptions or theory, look at practical designs and their results. After all, no point in trying to reinvent the wheel as it has all been done before.
Any extra/less capacitance/inductance that results in a difference not enough to measure.
My advice is don't use assumptions or theory, look at practical designs and their results. After all, no point in trying to reinvent the wheel as it has all been done before.
For class AB amps I’d say interdigitating the output pairs adds no benefit as only one half is conducting at a time. You should still however make sure the supply rail, 0V and output rail are overlaid/adjacent to each other to keep loop areas low.
On class A, since both output halves are conducting and have signal currrnt differences, if you interdigitate the output devices and carefully overlay/adjacent the supply, 0V and output rail with each other, you get a big reduction in loop area and therefore radiated EM fields. In a well designed class AB amp, you shouldn’t need to interdigitate the output devices for thermal performance.
Just my view. YMMV. 🙂
On class A, since both output halves are conducting and have signal currrnt differences, if you interdigitate the output devices and carefully overlay/adjacent the supply, 0V and output rail with each other, you get a big reduction in loop area and therefore radiated EM fields. In a well designed class AB amp, you shouldn’t need to interdigitate the output devices for thermal performance.
Just my view. YMMV. 🙂
It's great Luxman...
To be pissed off to distribute the P and N transistors for a better balance, all that to lock up the pcbs in a too small box which literally cooks the components...
I am collecting your opinions and thank you for that but still it appears that we cannot find the any reason the Japanese went into so much trouble...
Bonsai yes point is taken but the M03 is a typical class AB amp....
Huggygood been repairing some 50 pcs of M03 so far all of them had minor soldering issues here and there and indeed there is one spot that suffers from heat stress there also you get soldering issues but that is all.
Indeed this spot is wrong design but the rest is comming from the choice to place boards vertically not from heat stress.
All amplifiers in class AB operation and vertical boards suffer from that
Bonsai yes point is taken but the M03 is a typical class AB amp....
Huggygood been repairing some 50 pcs of M03 so far all of them had minor soldering issues here and there and indeed there is one spot that suffers from heat stress there also you get soldering issues but that is all.
Indeed this spot is wrong design but the rest is comming from the choice to place boards vertically not from heat stress.
All amplifiers in class AB operation and vertical boards suffer from that
I'm not going to contradict you, my experience with two of these amps is simply different, totally cooked and it must be recognized that with time and experience, I no longer like to touch these big stranded whales, too tedious, too many exotic components or unobtainium.
Now I have the chance to do things out of passion and not out of obligation.
You question relates to science, not opinion.
Technically speaking, there is no difference. People though, think they know better than proved and tested science and the laws of physics.
huggygood, I am also in that nice position to repair equipment, correctly, by choice and not demand.
Technically speaking, there is no difference. People though, think they know better than proved and tested science and the laws of physics.
huggygood, I am also in that nice position to repair equipment, correctly, by choice and not demand.