I just bought a mono subwoofer amp from Aiyima with the power supply built onto the board. It has a 24vdc output for a fan and also a 15 0 15v supply for a preamp. I haven't found a low pass filter preamp that takes a 15 0 15 supply but I do already have a single supply preamp that accepts 12v-30v DC or 9v-20v AC. It has only 2 wires for power hookup the + and -. Can I use the +15v and the 0v from the 15v+/- supply on the amps PCB and not connect anything to the -15v? I have searched but finding info on split rail systems is hard specially about only using half of it.
Thanks for your reply, I figured it would be ok but wanted to make sure. I wasn't sure if using half the supply and leaving the other half open would cause issues or not. I'd rather be safe than sorry.
There are a few oddball supplies that require equal loading of both outputs, but your sub amp should be fine.
Try to check on the maximum current the supply can source, and compare that to your preamp's needed current.
Be careful to observe polarity.
What is your single supply preamp circuit?
Try to check on the maximum current the supply can source, and compare that to your preamp's needed current.
Be careful to observe polarity.
What is your single supply preamp circuit?
It is also made by Aiyima but I modified it slightly to change it from a 12db slope to an 18db. I don't think they give current specs but I have used it with an old 18v linear wall wort rated at 500ma before. The Aiyima sub amps preamp circuit is also rated for 500ma so I'm pretty sure I'm good there. I like how the power supply is on the PCB and can use 220v or 110v mains by changing jumpers. It's a 1000w class d amp and they say it will do 300w rms@ 8ohm and 500w rms @ 4ohm. Also says that the amp section runs on 79v +/- rails.
The preamp board has decoupling caps already obviously so do you mean just parallel an additional cap to each one that's already there to increase it's capacity?
Since the amp is equipped with the means to rectify and smooth AC power, feeding it with DC, IMHO, you already have more capacitance than necessary.
Maybe some ceramic (decoupling) caps across the input or ferrite beads around the wire to suppress HF noise...
Maybe some ceramic (decoupling) caps across the input or ferrite beads around the wire to suppress HF noise...
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I won't be feeding the amp with DC power. I plan to hook it up to 110v mains through a fused IEC socket. The amp has a built in SMPS and has a 24vdc output for fans and a 15 0 15vac output for a preamp. I was asking about using the +15vac and the 0v to power my pre amp. The pre amp I have can accept AC or DC and has a 2 prong power input.