Hello,
I'm looking to build an 8 channels amplifier for sound art (installations, theatre...) and would appreciate some input as to best suited design. The goal is to have an ultra inexpensive and small multichannel amplifier.
Inexpensive is easily achieved stacking 20-30$ used hifi amplifier, but that's not fun to carry around. 4ch Behringer amps for around 350$ would work but multiply that by 2 and it's not cheap enough, especially as I plan to upgrade to 16 ch (make a second unit) within a year.
Requirements are:
-mid low power (50W-80W RMS 8R @ 0,1% THD)
-reasonable peak power, ability to have higher output for a couple seconds.
-driving all sort of loads, tactile transducers, small hifi speakers, computer speakers...
- some sort of OL/short/whatnot protection
- decent noise floor
- As cheap as possible.
- Reliable
- Compact/light
My first thought is buying a handful of LM3886 PCBs off ebay for dirt cheap, and stuff them on a large heatsink. Power them with a Meanwell SMPS. Would love to find a way to stuff them in a small 1u rack, and would absolutely love to have passive cooling (goes against light, I know).
But I'm concerned by the lack of balanced input and gain adjustment (strapping a pot on the input resistor is calling for high noise floor at lower gains), I'm worried that I won't find suitable symmetrical SMPS (and I would need to make my own PCB for single rail it would seem). I might want a tad more power.
So, would there be a better solution?
I had a look at the 6*100W Sure Electronics boards, but reliability seems a concern, with overheating. So, not suited. I also like the fact that the LM3886 are mono amps: stuff as many as needed, if one fries, easily replaced/repaired. I won't be treating the amp nicely xD.
Note: I can design PCBs and have them made, but Olimex is not taking orders anymore and it was the cheapest I could find. And I would have had trouble making them for <10$ per channel anyway. So this probably will be a too expensive route.
Thanks,
Nicolas
I'm looking to build an 8 channels amplifier for sound art (installations, theatre...) and would appreciate some input as to best suited design. The goal is to have an ultra inexpensive and small multichannel amplifier.
Inexpensive is easily achieved stacking 20-30$ used hifi amplifier, but that's not fun to carry around. 4ch Behringer amps for around 350$ would work but multiply that by 2 and it's not cheap enough, especially as I plan to upgrade to 16 ch (make a second unit) within a year.
Requirements are:
-mid low power (50W-80W RMS 8R @ 0,1% THD)
-reasonable peak power, ability to have higher output for a couple seconds.
-driving all sort of loads, tactile transducers, small hifi speakers, computer speakers...
- some sort of OL/short/whatnot protection
- decent noise floor
- As cheap as possible.
- Reliable
- Compact/light
My first thought is buying a handful of LM3886 PCBs off ebay for dirt cheap, and stuff them on a large heatsink. Power them with a Meanwell SMPS. Would love to find a way to stuff them in a small 1u rack, and would absolutely love to have passive cooling (goes against light, I know).
But I'm concerned by the lack of balanced input and gain adjustment (strapping a pot on the input resistor is calling for high noise floor at lower gains), I'm worried that I won't find suitable symmetrical SMPS (and I would need to make my own PCB for single rail it would seem). I might want a tad more power.
So, would there be a better solution?
I had a look at the 6*100W Sure Electronics boards, but reliability seems a concern, with overheating. So, not suited. I also like the fact that the LM3886 are mono amps: stuff as many as needed, if one fries, easily replaced/repaired. I won't be treating the amp nicely xD.
Note: I can design PCBs and have them made, but Olimex is not taking orders anymore and it was the cheapest I could find. And I would have had trouble making them for <10$ per channel anyway. So this probably will be a too expensive route.
Thanks,
Nicolas