Good morning and thank you very much again for your kind and precious help
Maybe I expressed myself badly
I was referring to the distance from transformer secondaries and the diodes bridge
It's not critical?
This is a very important point for me
Yes I know what a sawtooth voltage is
Maybe I expressed myself badly
I was referring to the distance from transformer secondaries and the diodes bridge
It's not critical?
This is a very important point for me
Yes I know what a sawtooth voltage is
Yes but do you understand that there is a sawtooth on the capacitor after the rectifiers?
I was just jooking about the distance ;-)
It is best to keep the secondary, the rectifier and the capacitor close together.
These parts have high current pulse-like signals and you want the wiring keep as short as possible to avoid radiating into the area and the amp.
Then you can connect from the capacitor to the amp by a longer cable if you wish; use thick wiring and twist the wires, again to limit radiating junk.
Jan
I was just jooking about the distance ;-)
It is best to keep the secondary, the rectifier and the capacitor close together.
These parts have high current pulse-like signals and you want the wiring keep as short as possible to avoid radiating into the area and the amp.
Then you can connect from the capacitor to the amp by a longer cable if you wish; use thick wiring and twist the wires, again to limit radiating junk.
Jan
well i have never seen it on a scope but i have seen it when simulating a basic power supply with LTSpice just transformer diodes and caps
and i have seen the effect of increasing capacitance
😀
thank you very much indeed So if i get it right the problem is AC inside the chassis ? actually i have seen some brands offering upgraded external power supplies like Naim and Mission The external power supplies have all rectification inside and a DC umbilical to the amp is used
I guess this is the only sane solution ? ok No more silly questions
Thanks a lot again
And you undwerstand why that is? Why it is a sawtooth, why not some other wave form?
Sorry to persist, but this is important if you are interested in how power supplies work.
And I believe you really want to know.
Jan
Honestly I have no clue
What kind of effects this causes?
I was impressed to see the effects of increasing capacitance
The commercial amps look poor in uF to me
I have seen AC umbilical only in preamps and headphone amps
I had a preamp kit
When I moved the transformer out of the metal chassis I feel something good
Maybe I was hearing things
What kind of effects this causes?
I was impressed to see the effects of increasing capacitance
The commercial amps look poor in uF to me
I have seen AC umbilical only in preamps and headphone amps
I had a preamp kit
When I moved the transformer out of the metal chassis I feel something good
Maybe I was hearing things
Thank you very much again I owe you an explanation
i cannot understand the theory behind phenomena I can only understand a graph a measurement
When i see an equation my brain stops to function I just get lost in the reasoning
the result of my effort is that I just get a headache
This is the reason why i am an avid watcher of videos on lab testing for instance Because i see things on measurement devices
I have been able to run some very basic simulation only because a kind Moderator has provided me with usable settings
Then i tried to sim some amp schematics stolen from service manuals Just for curiosity
I did not even tried to learn the theory behind LTSpice and what each setting really means It is beyond my abiltity to understand
I was very bad at math at school I chose chemical engineering for that I got a degree without really know anything Just copying from books
I can only copy and paste And sometimes i even copy badly
My very dream would be to learn how to make a pcb from the schematic of simple amps (i.e. with very low parts count) well regarded for their sound and build a prototype
Then i could test it on a scope A spectrum analyzer is a little too expensive The qa403 for instance is around 800 euro in Europe
I do not need much power I have decided to go for high efficiency speakers that will not need much power
It is a game for me
As an example i have an amp with a 40-0-40 transformer I have at hand a mighty 600VA 24-0-24 transformer that i would like to try
One idea would be to lower with a variac the 230VAC input voltage and see how the performance of the amp degrade
In this sense an audio anaylzer could show me easily the THD+noise graph But it is 800 euro A price above the market value of my own audio equipment I have a psychological block when I buy expensive stuff even if it's obviously of the highest quality
I love this DATS unit because gives me curves quite easily
For instance i am now doing impedance sweeps of anything with a coil i have at hand 🤓
Like these (i love aluminum cabinets They are neverending With the right drivers can do magic)
above a decent 8-10", a right xover and it is done
But i still need the instruments to check the freq response mostly
Then i have already seen some very great design SWs to design the xover
If i had to design a xover on the basis of the xover theory i would be completely lost
This is the sad situation
At school i had decent results only in lab activities Because i was following a protocol
I need to be told what to do step by step
Like a slightly retarded person
With all the respect for them of course
Maybe i am not that retarded Are the others that are too way ahead
i cannot understand the theory behind phenomena I can only understand a graph a measurement
When i see an equation my brain stops to function I just get lost in the reasoning
the result of my effort is that I just get a headache
This is the reason why i am an avid watcher of videos on lab testing for instance Because i see things on measurement devices
I have been able to run some very basic simulation only because a kind Moderator has provided me with usable settings
Then i tried to sim some amp schematics stolen from service manuals Just for curiosity
I did not even tried to learn the theory behind LTSpice and what each setting really means It is beyond my abiltity to understand
I was very bad at math at school I chose chemical engineering for that I got a degree without really know anything Just copying from books
I can only copy and paste And sometimes i even copy badly
My very dream would be to learn how to make a pcb from the schematic of simple amps (i.e. with very low parts count) well regarded for their sound and build a prototype
Then i could test it on a scope A spectrum analyzer is a little too expensive The qa403 for instance is around 800 euro in Europe
I do not need much power I have decided to go for high efficiency speakers that will not need much power
It is a game for me
As an example i have an amp with a 40-0-40 transformer I have at hand a mighty 600VA 24-0-24 transformer that i would like to try
One idea would be to lower with a variac the 230VAC input voltage and see how the performance of the amp degrade
In this sense an audio anaylzer could show me easily the THD+noise graph But it is 800 euro A price above the market value of my own audio equipment I have a psychological block when I buy expensive stuff even if it's obviously of the highest quality
I love this DATS unit because gives me curves quite easily
For instance i am now doing impedance sweeps of anything with a coil i have at hand 🤓
Like these (i love aluminum cabinets They are neverending With the right drivers can do magic)
above a decent 8-10", a right xover and it is done
But i still need the instruments to check the freq response mostly
Then i have already seen some very great design SWs to design the xover
If i had to design a xover on the basis of the xover theory i would be completely lost
This is the sad situation
At school i had decent results only in lab activities Because i was following a protocol
I need to be told what to do step by step
Like a slightly retarded person
With all the respect for them of course
Maybe i am not that retarded Are the others that are too way ahead
Hi thank you for the very valuable advice
I see that in the datasheets the secondaries DC resistance is mentioned
So I guess that is of some interest
Then I measured the impedance at 50Hz and I noticed that it can be quite higher than the DC resistance
And at higher frequencies even bigger
I wonder if this measure can tell anything about the quality of the transformer
I see that in the datasheets the secondaries DC resistance is mentioned
So I guess that is of some interest
Then I measured the impedance at 50Hz and I noticed that it can be quite higher than the DC resistance
And at higher frequencies even bigger
I wonder if this measure can tell anything about the quality of the transformer