Hi car audio experts. I am looking to set up an amp for off-the-grid PA (music and speech) to run on a 12V battery. A single channel (mono) is all that is needed. The speakers would be one or two 8-ohm. Amps like the Lepai LP2020 are limited to about 7 true watts at 12V supply with an 8-ohm speaker, double that for a 4-ohm load. So how to get more watts? I'm aiming for something around 100 watts, with the least draw on the battery and hopefully at low cost.
One idea I'm investigating is to use a readily available class D car subwoofer amp. E.g., the Kicker DX250.1 is rated 140 watts RMS into a 4-ohm load. The little info I have found on these amps indicates that they have a switching power supply internally that creates high enough DC voltages to reach the target power output. It seems much easier to use such a pre-built amp than to try and build my own step-up power supply or to patch together such a supply and a separate amp.
But, these subwoofer amps have a built in low pass filter, and I want to use it as a full-range amp. I would think that modifying it to bypass the filter would be easy enough? But can the amp circuit itself handle frequencies up to, say, 15 KHz, or is it inherently unsuitable for that, e.g., due to the use of too low a switching frequency?
If there are similar amps that already are full-range let me know. A stereo one would not hurt, even if I only use one side, as long as it's small and efficient and inexpensive. But if modifying a sub amp is feasible, it may be the ideal solution.
One idea I'm investigating is to use a readily available class D car subwoofer amp. E.g., the Kicker DX250.1 is rated 140 watts RMS into a 4-ohm load. The little info I have found on these amps indicates that they have a switching power supply internally that creates high enough DC voltages to reach the target power output. It seems much easier to use such a pre-built amp than to try and build my own step-up power supply or to patch together such a supply and a separate amp.
But, these subwoofer amps have a built in low pass filter, and I want to use it as a full-range amp. I would think that modifying it to bypass the filter would be easy enough? But can the amp circuit itself handle frequencies up to, say, 15 KHz, or is it inherently unsuitable for that, e.g., due to the use of too low a switching frequency?
If there are similar amps that already are full-range let me know. A stereo one would not hurt, even if I only use one side, as long as it's small and efficient and inexpensive. But if modifying a sub amp is feasible, it may be the ideal solution.