i want to build my own amp for my car sub. i'm just starting to collect the parts for it. i dont want to spend all that money on an amp, so i figured i'd just build one.
whats the best way to go?? bridge 2 opa541 chips which can run off of 12V (how much power would that deliver???) or (try and) build a SMPS to turn 12VDC into +/-60 or so??
would the bridged 541 produce good sound, loud volume yet low distortion??
the speaker is a 8-ohm 8" speaker.
whats the best way to go?? bridge 2 opa541 chips which can run off of 12V (how much power would that deliver???) or (try and) build a SMPS to turn 12VDC into +/-60 or so??
would the bridged 541 produce good sound, loud volume yet low distortion??
the speaker is a 8-ohm 8" speaker.
running bridged off 12 volts into an 8 ohm speaker would give about 10 watts rms off memory. Not really worth the effort, i doubt you'd get over road noise before you clipped it.
I intend to build a smps (getting there, slowly) basically like Rods design (sg3525 based), and then probably P3A amps off it, running around +/-35v . However, for 8 ohm i can see where the higher voltage would come into play.
I intend to build a smps (getting there, slowly) basically like Rods design (sg3525 based), and then probably P3A amps off it, running around +/-35v . However, for 8 ohm i can see where the higher voltage would come into play.
since that chip can run off of a single power supply, is there any kind of linear power boosting circuit i can build to boost the 12V to something higher?? I dont want switching since they are more complicated to build.
here are another idea for you,
you can find the other woofers, which impedance are 4 Ohms or 2 Ohms better, eight inchs. But the cost will increase.
In fact that is very difficulty for the DC-DC convertor build if you are an amateur, you need the coil, MOSFET for switching, and filter, you also need the PCB layout(that is very important)......
you can find the other woofers, which impedance are 4 Ohms or 2 Ohms better, eight inchs. But the cost will increase.
In fact that is very difficulty for the DC-DC convertor build if you are an amateur, you need the coil, MOSFET for switching, and filter, you also need the PCB layout(that is very important)......
i found this schematic while searching.
I have a source for all the parts, except what type of a torrid is needed, and does it even have to be a torrid?
Also, there is a connection labeled Remote. why do i need a remote on it? Since i dont want it, how many other parts connecting to it can i get rid of?
Also, there are +/- 30V feedback connections. what are those for? Can i get rid of them?
Finally, do i need the three 100uh inductors?
EDIT: Do i need that fan also? if not, how many parts connecting to it can i get rid of?
EDIT: Also, how much amperage should this circuit produce?
I have a source for all the parts, except what type of a torrid is needed, and does it even have to be a torrid?
Also, there is a connection labeled Remote. why do i need a remote on it? Since i dont want it, how many other parts connecting to it can i get rid of?
Also, there are +/- 30V feedback connections. what are those for? Can i get rid of them?
Finally, do i need the three 100uh inductors?
EDIT: Do i need that fan also? if not, how many parts connecting to it can i get rid of?
EDIT: Also, how much amperage should this circuit produce?
I don't think it has to be a toroid, i'm not a transformer expert though (not a fan of that class in my course 🙂.
Remote is car use, turns the amp on and off when the headunit/cd player is turned on and off, so the amp isn't idling overnight draining ya battery.
the Feedback means the IC will control switching pattern and length (pwm) to maintain 30 volt rails (ratio dependant). Without this, it basically goes to max with no load, and comes down under load.
Someone said inductors were purely for the feedback circuit, to make the pulse work better, i guess it might get rid of high freq transients or something, a lot don't have them.
Fan depends entirely on your heatsinking, most amps don't have a fan. Allows an easy connection though.
I think Rod said the circuit will do enough for 6 gainclones, its very toroid dependant.
http://sound.westhost.com/project89.htm is best source of info for this circuit.
Remote is car use, turns the amp on and off when the headunit/cd player is turned on and off, so the amp isn't idling overnight draining ya battery.
the Feedback means the IC will control switching pattern and length (pwm) to maintain 30 volt rails (ratio dependant). Without this, it basically goes to max with no load, and comes down under load.
Someone said inductors were purely for the feedback circuit, to make the pulse work better, i guess it might get rid of high freq transients or something, a lot don't have them.
Fan depends entirely on your heatsinking, most amps don't have a fan. Allows an easy connection though.
I think Rod said the circuit will do enough for 6 gainclones, its very toroid dependant.
http://sound.westhost.com/project89.htm is best source of info for this circuit.
Saving money is not a good reason to build an amp. Saving money is why you walk through pawn shops, swap meets, and yard sales looking for a good deal on a used amp.
It'll cost at least as much in parts to build an amp as to buy one, because you can't get parts as cheap as they do in Taiwan, and you'll have to buy whole rolls of copper wire when you only need 6", and pay UPS to deliver the toroid core, etc etc.
How about calling around at the local car audio stores and see if they have any broken amps you can have cheap? Then maybe you can fix it, or at least salvage the case and transformer. Maybe if the amp portion is dead, you can still use the power supply section.
It'll cost at least as much in parts to build an amp as to buy one, because you can't get parts as cheap as they do in Taiwan, and you'll have to buy whole rolls of copper wire when you only need 6", and pay UPS to deliver the toroid core, etc etc.
How about calling around at the local car audio stores and see if they have any broken amps you can have cheap? Then maybe you can fix it, or at least salvage the case and transformer. Maybe if the amp portion is dead, you can still use the power supply section.
just buy an amp.... even a 30watt rms Avalanche amp would be cheaper to buy than making a 30watt amp.. 😛 $70... sure, its only 30watts, but to get 30watts you need to step the voltage up.. so... yeah.. lol
well all the parts for the PS i can get free samples of or already have (i probably also have a torrid that would work).
The amp would be a lm4651/4652 170W amp.
i guess i shouldnt have said it that way, i want to build it for the fun also.
The amp would be a lm4651/4652 170W amp.
i guess i shouldnt have said it that way, i want to build it for the fun also.
soundNERD said:
Output voltage collapses with any sort of reasonable loading,
and they aren't the easiest thing to drive starting with 12V dc.
🙂 sreten.
ok thanks, i was just looking in my radioshack getting started in electronics book and saw them, it didn't say anything about them, just the schematic, and it looked easier to use than a torrid/rectifier/caps solution.
if its 10 watts into 8 ohm then thats 20 watts into 4 ohm. I think even 10 watts is enough to get above road noise Thats about 2 gazillion watts pmpo and more than most car amps will ever put out.😉
look in a TL494 controller IC datasheet.
I have made three units for DC step up (although not isolated) was simple to build, just needed a choke coil (not a transformer) and got about 85% efficiency with minimun of parts. my units put out about up to 30V with a 12V input. haven't torture tested them yet. probably 2A or so. maybe more with more MOSFETS and bigger coils.
I have made three units for DC step up (although not isolated) was simple to build, just needed a choke coil (not a transformer) and got about 85% efficiency with minimun of parts. my units put out about up to 30V with a 12V input. haven't torture tested them yet. probably 2A or so. maybe more with more MOSFETS and bigger coils.
do you have the exact schematic you used to get that 30V output?
and i wonder, could i build 2 and then use a voltage inverter on one to get +/-30V???
and i wonder, could i build 2 and then use a voltage inverter on one to get +/-30V???
Luke said:
how can a 10W amp put out more power than most car amps will ever put out?
and what exactly is PMPO? I've seen these little wimpy computer speakers claim they were 500W then in little text beloiw it says PMPO. There is no way since the transformer on them is like 500mA, so how could it even come close to producing 500W??
Actually, I think I am just going to go with the schematic I originally talked about with the MOSFETs and IC.
Is it OK that I am using Fairchild HUF76423P3 MOSFETS instead of the BUZ11? I typed BUZ11 into their cross reference, and that was the only one they had samples of. It handles 33A, or 3A more than the BUZ11, and also 60V which is 10V more. The only difference is it is a Logic Level UltraFET Power MOSFET. Does that matter?
Is it OK that I am using Fairchild HUF76423P3 MOSFETS instead of the BUZ11? I typed BUZ11 into their cross reference, and that was the only one they had samples of. It handles 33A, or 3A more than the BUZ11, and also 60V which is 10V more. The only difference is it is a Logic Level UltraFET Power MOSFET. Does that matter?
PMPO
Pretty Moronic Power Rating!
Thats what that stands for, catalogue companies started that term i think, i blame the Tim the tool man culture, HUA HUA HUA!
More power means more ego! oh well forget about it.
Pretty Moronic Power Rating!
Thats what that stands for, catalogue companies started that term i think, i blame the Tim the tool man culture, HUA HUA HUA!
More power means more ego! oh well forget about it.
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