My powered sub's amp is 10+ years old and over heats/cuts on music. Movies are fine.
Instead of buying an external amp to power it, I'd like to build my own.
I've taken apart an old onkyo 809 for the EI transformer. Everyone seems to use to toroidals.
Planning on just a 150 watt clean mono channel amp for the sub. Love that there are additional power leads on the transformer for adding more channels as I learn.
Looking for any advice on boards and power supply. Will just use rca inputs, but would like to add a switch for xlr in the future.
Looking at this amp.
Sure Electronics AA-AB31511 1x500W Class D Audio Amplifier Board Compact - T-Amp
Only wish there was volume but not truly necessary.
Looking at the build photos, I see caps bigger than the one on my ac compressor! Are those really necessary?
Instead of buying an external amp to power it, I'd like to build my own.
I've taken apart an old onkyo 809 for the EI transformer. Everyone seems to use to toroidals.
Planning on just a 150 watt clean mono channel amp for the sub. Love that there are additional power leads on the transformer for adding more channels as I learn.
Looking for any advice on boards and power supply. Will just use rca inputs, but would like to add a switch for xlr in the future.
Looking at this amp.
Sure Electronics AA-AB31511 1x500W Class D Audio Amplifier Board Compact - T-Amp
Only wish there was volume but not truly necessary.
Looking at the build photos, I see caps bigger than the one on my ac compressor! Are those really necessary?
Attachments
Hi
a 2nd hand transformer is not a bad thing - i read in the manuel that the max power consumption is about 710WATT @ 230V - so its big enough i guess
Your Onkyo Transformer give you 48V and after rectifier =about 67V DC its too much for the requested power supply voltage of max 50V of this amp!
Please use the 24VAC line = 34VDC its fine.
the caps on the amp board are needed! these are responsible to deliver the power at fast bursts which the power supply can´t handle so quick.
chris
a 2nd hand transformer is not a bad thing - i read in the manuel that the max power consumption is about 710WATT @ 230V - so its big enough i guess
Your Onkyo Transformer give you 48V and after rectifier =about 67V DC its too much for the requested power supply voltage of max 50V of this amp!
Please use the 24VAC line = 34VDC its fine.
the caps on the amp board are needed! these are responsible to deliver the power at fast bursts which the power supply can´t handle so quick.
chris
These Onkyo AVR´s are really hot. In a 2 channel configuration the program power is ridiculous, it can hit 500 W/4 ohm.
When all identical 7 amps are driven, this is reduced to about 7x 100 w/4 ohms. This is still quite some noise in the living room!
What you can build around this very capable transformer depends on you and your skill´s / knowledge.
So the transformer is great. Build a good and simple symetric power supply, with a bridge rectifier or 4 diodes, minimum 25 amps, some 1-4 mF MKP or MKT capacitors and about 20.000uF in electrolitc capacitors, rated 80 volt. I prefer to use more smaller capacitors, like 4x 4700uF or 6x 3300 instead of two large ones. This is about the minimum PS for a good quality sub amp.
Very interesting is the L30D for your needs, it is about 30$ and seems to work quite well.
Konfektionierte L30D 850W Digitale Mono-Verstarkerplatine IRAUDAMP9 | eBay
Your question about the "large capacitor": Yes, they store not only the energy for the next bass vibration, but take the ripple (100 or 120 Hz hum) out of the rectified AC current.
You may add a speaker protection board, that also prevents a "thump" when the amp starts and closes down.
If you are not to sure what all this means, ask BEFORE you burn money. Some stuff can explode, if wired wrong, no joke! 67 volt are able to kill you with a little luck.
The simplest would to buy amp, power supply and speaker protection to complete your transformer as finished modules. Don´t think any one can wire 4 components in half an hour, this is still serious work not taken to easy, if you want something functioning.
The best way to get a negative result is "to wire just for a test". This gets expensive in most cases. Do it once, right.
Any conection has to be made of decent wire, well insulated and running in a defined way from component to component. There are many examples in the amp build picture thread.
Hope that helps!
PS Sure stuff: 4 times more expensive? Yes. Any better than 1/4 the price? No. Just look good with the black PCB...
When all identical 7 amps are driven, this is reduced to about 7x 100 w/4 ohms. This is still quite some noise in the living room!
What you can build around this very capable transformer depends on you and your skill´s / knowledge.
So the transformer is great. Build a good and simple symetric power supply, with a bridge rectifier or 4 diodes, minimum 25 amps, some 1-4 mF MKP or MKT capacitors and about 20.000uF in electrolitc capacitors, rated 80 volt. I prefer to use more smaller capacitors, like 4x 4700uF or 6x 3300 instead of two large ones. This is about the minimum PS for a good quality sub amp.
Very interesting is the L30D for your needs, it is about 30$ and seems to work quite well.
Konfektionierte L30D 850W Digitale Mono-Verstarkerplatine IRAUDAMP9 | eBay
Your question about the "large capacitor": Yes, they store not only the energy for the next bass vibration, but take the ripple (100 or 120 Hz hum) out of the rectified AC current.
You may add a speaker protection board, that also prevents a "thump" when the amp starts and closes down.
If you are not to sure what all this means, ask BEFORE you burn money. Some stuff can explode, if wired wrong, no joke! 67 volt are able to kill you with a little luck.
The simplest would to buy amp, power supply and speaker protection to complete your transformer as finished modules. Don´t think any one can wire 4 components in half an hour, this is still serious work not taken to easy, if you want something functioning.
The best way to get a negative result is "to wire just for a test". This gets expensive in most cases. Do it once, right.
Any conection has to be made of decent wire, well insulated and running in a defined way from component to component. There are many examples in the amp build picture thread.
Hope that helps!
PS Sure stuff: 4 times more expensive? Yes. Any better than 1/4 the price? No. Just look good with the black PCB...
I'm now searching for a power supply and recruiter. The Sure option on parts express looks great. What I'm finding on amazon is not so impressive.
4*10000uF/50V Rectifier Filter Power Supply Finished Board PSU https://www.amazon.com/dp/B008ONJQEG/ref=cm_sw_r_cp_tai_fosBDb1G0GZXW
4*10000uF/50V Rectifier Filter Power Supply Finished Board PSU https://www.amazon.com/dp/B008ONJQEG/ref=cm_sw_r_cp_tai_fosBDb1G0GZXW
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.