Tbh even though your subwoofer is only 250 watts RMS I would still get something a little more then 300 watts maybe a 500 watt amplifier so you have some headroom and the ability to upgrade the subwoofer if you want down the road. Always better to have more power available then not enough. I would consider any of these below
The 1st one is a Rockford Fosgate that has 300 watts RMS at 4ohms & 500 watts RMS at 2ohms
This one is a Kenwood Excelon X501-1 which does 300 watts RMS at 4 ohms and 500 watts RMS at 2 ohms
Amazon.com: Kenwood Excelon X501-1 Class D Mono Power Amplifier : Electronics
This one is refurbished but JBL makes a decent monoblock as well.
JBL CLUB-5501 Monoblock Amplifier Renewed • 1300W Peak 550W RMS Club Series Class D Monoblock Amplifier • 370 Watts RMS x 1 @ 4 ohms • 550 Watts RMS x 1 @ 2 ohms • Total Peak Power: 1300 Watts • Slim Chassis design to fit more vehicles • Variable Bass Boost • Heavy duty aluminum alloy...
This kenwood is 300 watts at 4ohms and 500 at 2 ohms
Kenwood KAC-D5101 • Class D Mono Amplifier 1000 Watts MAX Power • 300 Watts RMS x 1 @ 4 ohms • 500 Watts RMS x 1 @ 2 ohms • Total Peak Power: 1000 Watts • Speaker Level Input • Signal Sensing Turn-On • Variable Low Pass Filter: 50-200 Hz at 24 dB per octave • Variable Bass Boost: 0 to...
Alpine MRV-M500 • 500W V-Power Series Class D Monoblock Digital Amplifier • RMS: 300W x 1 @ 4 ohms 500W x 1 @ 2 ohms • Total Peak Power: 1000W • CEA-2006 Compliant Amplifier • 4-Channel Speaker-Level Inputs • Heavy Duty Aluminum Alloy Heat-Sink • Dimensions: 7-7/8"W x 7-7/8"L x 2-3/16"H
MTX Audio THUNDER500.1 • 500W RMS Class D 1-Channel Monoblock Power Car Amplifier • RMS: 300W x 1 @ 4 ohms 500W x 1 @ 2 ohms • Total Peak Power: 1000W • 3-Way Protection Circuitry • Selectable Bass Boost 0-6-12 dB • Class D Circuitry • Dimensions: 6-5/16"W x 8-15/16"L x 2-1/4"H
Alpine S-A60M • S-Series Monoblock Class-D Amplifier 600W RMS • Alpine S-Series Mono Power Amplifier - S-A60M • 400W RMS x 1 4ohm 14.4V < 1% THD+N • 600W RMS x 1 2ohm 14.4V < 1% THD+N • Remote bass knob compatible
Personally I think I would go for the Pioneer below, 300 watts at 4ohms, 500 watts at 2ohms and 800 watts at 1ohm. Giving you quite a bit of room for upgrading the subwoofer down the line. Obviously check all places for the price but
Sonicelectronix is a great place to buy from.
Pioneer GM-D8701 • 800W RMS Class D Monoblock GM Digital Series Amplifier • RMS: 300W x 1 @ 4 ohms 500W x 1 @ 2 ohms 800W x 1 @ 1 ohm • Total Peak Power: 1500W • CEA-2006 Compliant • Variable Bass Boost: 0 to +18 dB • Class D Circuitry • Dimensions: 10-7/16"W x 2-3/8"D x 7-7/8"H
This is the same model as above just the older version of it. They say out of stock but you can find it somewhere else
Pioneer GM-D8601 Ships as 2019 model: Pioneer GM-D8701 • 800W RMS Class D Monoblock GM Digital Series Amplifier • RMS: 300W x 1 @ 4 ohms 500W x 1 @ 2 ohms 800W x 1 @ 1 ohm • Total Peak Power: 1500W • CEA-2006 Compliant • Variable Bass Boost: 0 to +18 dB • Class D Circuitry • Dimensions...
Amazon has them for 199.99 and have 4 left. Pay attention to the RMS ratings that is what matters. Plus they have tested higher as well by Williston so you have headroom as I said above. Really nice amplifiers all around.
Buy Pioneer GM-D8701 Gm Series 1, 600 Watt Monoblock Class D Amp: Mono Amplifiers -
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