I'm looking for a 2 channel amplifier board that could work with a transformer that I already have that outputs 38.5v-0-38.5 and 14.5-0-14.5. I'm looking to drive some desktop speakers and some statement floor standing speakers in the future. As far as what class amplification I am unsure what to go with. I have found some boards such as https://www.ebay.com/itm/265784869001?hash=item3de2034089:g:L3EAAOSwvZpi1O55 but in my experience some chinese boards can be somewhat hit or miss so any guidance would be appreciated.
Your transformer will put out rectified +/-55V rails, so any amplifier happy with such rails will do.
Expect some 120-150W RMS into 8 ohm, so use this rating as a guide.
Your board looks good and might do but I am not too sure WHY a modern design would choose metallic TO3 transistors to begin with, even worse much desired and expensive so MUCH faked MJ15024, the components shown cost is higher than $99, lots of red flags.
As in: "if it looks TOO good to be true ...."
Expect some 120-150W RMS into 8 ohm, so use this rating as a guide.
Your board looks good and might do but I am not too sure WHY a modern design would choose metallic TO3 transistors to begin with, even worse much desired and expensive so MUCH faked MJ15024, the components shown cost is higher than $99, lots of red flags.
As in: "if it looks TOO good to be true ...."
Stick to boards from well known suppliers, here in India the 5200 / 1943 ready PCBs are popular, and also 80N08 Mosfets are used in higher rated amps.
And do check out your transformer under load, before making a purchase.
And do check out your transformer under load, before making a purchase.
Exactly.....the metal T03 transistors are likely what market research reveals as preferred by newbies - the guys who mostly buy the kits and assembled boards, because the transistors look big, tough and encased in shiny metal - just like the transistors in big, old and respected amplifiers from the 1970s. So everyone gets shiny TO3s, even if what's really inside the can is junk in comparison with the OEM product.
Does it matter if they are inferior semis? Only deaf party animals would need such high power in the home, when most users will need to restrict the output to some level less than 5W, no matter what their system is capable of. So, we often read positive feedback about products that don't actually measure up to claims.
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Small world 😉
I usually tell my customers: "no matter whether you have a 5W amp, a 50W or a 500W one .... you CAN NOT use it at higher than 5W (average) on most days, and maybe the occasional 50/60W party some Friday or Saturday night .... Neighbours and Police will take care of that" 🙄
You can only take that so far. If a “200 watt” amplifier board is only run on +/-18 volts it may run forever on fake MJ15024’s - and be more than loud enough for home use. But run it up on +/-55 and you can still blow those fake transistors, even when putting out only 5 watts of average power. Draw 5 amps into an inductive load (for just a few milliseconds, not long enough to bring the cops) they go short. Maybe not the first time, but eventually someone loses in a game of Russian Roulette.
The quad 405 is an excellent amp with a lot of reviews on this forum and will work with your power supply. I have built using 405 and 405-2 modules - very good results. The thread is here, and on a lot of other forums as well, so you can read users experiences and advice is available
https://www.diyaudio.com/community/threads/quad-405-next-gen.388154/
These are the best boards i have ever heard and will work with your power supply
https://www.ebay.co.uk/itm/27495811...a0++UFS47VyBBh6d3imtI/RJrv|tkp:Bk9SR4LBr5aqYQ
https://www.diyaudio.com/community/threads/quad-405-next-gen.388154/
These are the best boards i have ever heard and will work with your power supply
https://www.ebay.co.uk/itm/27495811...a0++UFS47VyBBh6d3imtI/RJrv|tkp:Bk9SR4LBr5aqYQ
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