Ive got a pair of amps with bad amplifier sections and am wondering if rather than throwing them out, giving them new life by reusing the enclosure, power supply section and heatsink by adding some class D modules.
As I understand the schematic, there is a 15v supply coming into the amplifier section. I am planning to try to isolate the power supply section from the rest of the components and remove them making room, and am curious what chips may lend well to my scenario? Ive got a nice TPA3116 and would like to find something more powerful.
I know some have dabbled extensively in Class D, and have seen some promising pieces at very low prices, but am doubful that should be my primary deciding factor. I look forward to your suggestions, thanks in advance.
As I understand the schematic, there is a 15v supply coming into the amplifier section. I am planning to try to isolate the power supply section from the rest of the components and remove them making room, and am curious what chips may lend well to my scenario? Ive got a nice TPA3116 and would like to find something more powerful.
I know some have dabbled extensively in Class D, and have seen some promising pieces at very low prices, but am doubful that should be my primary deciding factor. I look forward to your suggestions, thanks in advance.
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The only power supply available is a single +15V rail? That will rather limit your output power if so and the TPA3116 would be a suitable choice. No other chip will give you more power as the rail voltage is what's restricting the output.
All i see in the schematic is a 15v line... the amp was originally a 100w amp... maybe I am misreading the schematic? Unless there are other non class D designs that achieve such numbers using 15v?
You may be missing some details in the schematic. A 100W amp into 8ohms would typically have power rails in excess of 40V.
Fair enough assumption. I cannot wrap my head around this schematic.
Service manual is in here.
Onkyo TX-8050 Manual - Network Stereo Receiver - HiFi Engine
When turned on, speaker protect trips and shuts off instantly. As I understand it, there are issues with the amplifier that resulted in most of them failing and cannot really diagnose and repair that kind of problem easily. so am hoping I can repurpose the power supply along with the heat sinks and enclosure to make a new amp to use in my active biamp rig. The cases are in great shape and can make something nice I think. Beats a 3116 on a slab of MDF 😛
Service manual is in here.
Onkyo TX-8050 Manual - Network Stereo Receiver - HiFi Engine
When turned on, speaker protect trips and shuts off instantly. As I understand it, there are issues with the amplifier that resulted in most of them failing and cannot really diagnose and repair that kind of problem easily. so am hoping I can repurpose the power supply along with the heat sinks and enclosure to make a new amp to use in my active biamp rig. The cases are in great shape and can make something nice I think. Beats a 3116 on a slab of MDF 😛
HiFi Engine looks to be blocked here. I found a low-res version of the poweramp schematic here : http://bilder.hifi-forum.de/medium/...tic-detail-power-amplifier-circuit_261397.jpg
Its rather blurry but does appear to show nominal 50V rails. They are beyond any integrated classD amp I'm aware of so I'd suggest acquiring some IRS2092-based amp boards.
Its rather blurry but does appear to show nominal 50V rails. They are beyond any integrated classD amp I'm aware of so I'd suggest acquiring some IRS2092-based amp boards.
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I used an old Dynaco ST150 that never worked right. Bumped up the power supply to 33000uf caps and drive a ClassDaudio module.
Also a rust bucket beat to crap AB international 900 with 20000uf caps to power a cheapo set of 2092 modules.
If you can get the chassis cheap it's a great way to go. Otherwise just buy and Carvin HD3000 and be done.
Also a rust bucket beat to crap AB international 900 with 20000uf caps to power a cheapo set of 2092 modules.
If you can get the chassis cheap it's a great way to go. Otherwise just buy and Carvin HD3000 and be done.
One caveat when retrofitting old equipment with class-d is to be cautious of how the outputs a wired. Some old amps can have the negative speaker terminals tied together which won't turn out so well if you're using a module with BTL outputs.
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