Here are my unsolved mysteries of amps please friends can u give me some advice
ok friends some of my simple questions are...
1. Is there any relation between the oversize magnet size and the type of amp ( like what ive heard that chip amp cannot drive heavy magnet woofers like (155 mm magnet size ) is it true?)
secondly can i use 3rd order crossover with the LM 4780? by making the same pcb which is given in the datasheet?
how to calculate the power ratings for the amplifier like my LM 4780 i know that the voltage ratings typical values are +/- 35 volts but what about current ratings how to calculate this... ?
please give me reply for these....
ok friends some of my simple questions are...
1. Is there any relation between the oversize magnet size and the type of amp ( like what ive heard that chip amp cannot drive heavy magnet woofers like (155 mm magnet size ) is it true?)
secondly can i use 3rd order crossover with the LM 4780? by making the same pcb which is given in the datasheet?
how to calculate the power ratings for the amplifier like my LM 4780 i know that the voltage ratings typical values are +/- 35 volts but what about current ratings how to calculate this... ?
please give me reply for these....
yeah i want to use the passive crossover like the dynaudio audience speakers they use the 3rd order crossovers so if i want to hook this LM4780 with that then what happens ...
like the other chips like stk they blow up... is it the same case with LM 4780?
another question ive been trying to get reply but nobody is replying....that is....
what are the toroidal trans ratings that must be used with this LM4780 chips...yes ive searched the datasheet i got only voltage ratings i dont know the current ratings like...
we i want to use the 35-0-35 toroidal transformer and what about the current ratings? just telll me one number which matches perfectly and will be highly stable....
like the other chips like stk they blow up... is it the same case with LM 4780?
another question ive been trying to get reply but nobody is replying....that is....
what are the toroidal trans ratings that must be used with this LM4780 chips...yes ive searched the datasheet i got only voltage ratings i dont know the current ratings like...
we i want to use the 35-0-35 toroidal transformer and what about the current ratings? just telll me one number which matches perfectly and will be highly stable....
!!!!!!!!!!
Hi Sandeep!!!!
As Richie00boy!! explained , there's no relationship between big magnets and driving them!!
1. The chip lm4780 should be able to drive those drive unit you have but find its Impedence.
2. Use any order crossover that no way related to destruction of chips.
3. Remember these chips are recommended to work in +/- 35 volt DC so lessen the secondary turnings depending on the load you would like to drive.
4. And of course the current rating again depends on the load you are applying.
I strongly recommended you refer this Fantastic forum & some audio books, and then go ahead to projects.
Thanks
Arasuk
Hi Sandeep!!!!
As Richie00boy!! explained , there's no relationship between big magnets and driving them!!
1. The chip lm4780 should be able to drive those drive unit you have but find its Impedence.
2. Use any order crossover that no way related to destruction of chips.
3. Remember these chips are recommended to work in +/- 35 volt DC so lessen the secondary turnings depending on the load you would like to drive.
4. And of course the current rating again depends on the load you are applying.
I strongly recommended you refer this Fantastic forum & some audio books, and then go ahead to projects.
Thanks
Arasuk
any freeware for room acoustics with 3d multicolour and along with 3d waterfall plots
are there any softwares for room acoustics with 3d plots with multicolour 3d waterfall plots.. etc... i need something like that...
please give me some links if u know any of them....other than LSPCAD, WINISD etc..
ive searched the forums... i couldnt find them.. please give me some names of the free softwares.. or demo ones.....
are there any softwares for room acoustics with 3d plots with multicolour 3d waterfall plots.. etc... i need something like that...
please give me some links if u know any of them....other than LSPCAD, WINISD etc..
ive searched the forums... i couldnt find them.. please give me some names of the free softwares.. or demo ones.....
can i use this kind of power supply? for the LM4780?
Like instead of using the 500VA 22-0-22 toroidal transformer with 10,000uf of capacitor per rail and totally about 20,000uf per LM4780? which gives an equivalent of approximately 20 amperes of current at critical stages
or
using a 100VA with 22-0-22 toroidal transformer with about 20,000uf of capacitor per rail and totally about 40,000uf per LM4780 whcih give and equivalent of approx 40 amps of current at crital stages....
which one do u suggest and why?
I think second one is the best one...for performance and i want to use only 4700uf caps connected in parallel ( i know the size becomes large but it becomes much more cheaper for me...
Like instead of using the 500VA 22-0-22 toroidal transformer with 10,000uf of capacitor per rail and totally about 20,000uf per LM4780? which gives an equivalent of approximately 20 amperes of current at critical stages
or
using a 100VA with 22-0-22 toroidal transformer with about 20,000uf of capacitor per rail and totally about 40,000uf per LM4780 whcih give and equivalent of approx 40 amps of current at crital stages....
which one do u suggest and why?
I think second one is the best one...for performance and i want to use only 4700uf caps connected in parallel ( i know the size becomes large but it becomes much more cheaper for me...
well actually the chip current is limited to 11.5 amps right...>>> well if that is the case then can i use about *****120VA *****22-0-22 with 20,000uf per rail and total 40,000uf of capacitor for one Single LM4780 chip? so at max it may draw about 15amps is it right and note that can I USE 120VA toroidal trans with that value of capcitance?
coz i dont want to spend much on transformers..
coz i dont want to spend much on transformers..
diysmartdeep21 said:
I'm not convinced you really want me to do that
Think of the crossover like a variable resistor in series with the drive unit. As the signal frequency approaches the crossover frequency, the resistance of the variable resistor is increased so less power gets to the drive unit. As the crossover frequency is passed the resistor gets more and more resistive.
well what u say is right and its applicable with the first order crossover and
in the case of higher order crossovers the concept becomes totally opposite like it will be exactly using an variable resistor connected in parallel with the driver ...
right >>>>
now u got the idea what happens with the higher order crossovers... well the above case is with the 2nd order crossover then imagine about 6th order... that means that they have got similar ie about 3 variable resistors which are connected in parallel... so what about this case... can u explain...??
in the case of higher order crossovers the concept becomes totally opposite like it will be exactly using an variable resistor connected in parallel with the driver ...
right >>>>
now u got the idea what happens with the higher order crossovers... well the above case is with the 2nd order crossover then imagine about 6th order... that means that they have got similar ie about 3 variable resistors which are connected in parallel... so what about this case... can u explain...??
HEY PLEASE ANYBODY ANSWER THIS...
well actually the chip LM4780 current is limited to 11.5 amps right...>>> well if that is the case then can i use about *****120VA *****22-0-22 with 20,000uf per rail and total 40,000uf of capacitor for one Single LM4780 chip? so at max it may draw about 15amps is it right and note that can I USE 120VA toroidal trans with that value of capcitance?
coz i dont want to spend much on transformers..
well actually the chip LM4780 current is limited to 11.5 amps right...>>> well if that is the case then can i use about *****120VA *****22-0-22 with 20,000uf per rail and total 40,000uf of capacitor for one Single LM4780 chip? so at max it may draw about 15amps is it right and note that can I USE 120VA toroidal trans with that value of capcitance?
coz i dont want to spend much on transformers..
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