Filters
106 products
Shop 4 channel amplifiers at JS Ultimate Sounds — the most versatile amp in car audio. A 4-channel runs a complete front and rear speaker stage, or powers your doors while bridging into a subwoofer from the same chassis.
What a 4-Channel Amp Is For
Three common setups:
- Full speaker stage — four channels to four speakers, the classic upgrade from head-unit power
- Front stage + bridged sub — two channels to your door speakers, two bridged into a subwoofer
- Active front stage — separate channels for midrange and tweeters, for builds running a DSP
How Much Power Do You Need?
Match the amp's RMS per channel to your speakers' RMS rating, within about 20%. Typical coaxials want 60–100W per channel; pro-audio midrange can use 150W and up. Popular picks: the Down4Sound JP84 for standard door speakers, the dyno-certified JP234 for a full system or bridged sub, and the JP284 for high-output pro audio builds. Read the JP234 review or the full JP series guide.
Setting It Up Right
Two rules decide whether a 4-channel sounds good: engage the high-pass filter (80–100Hz) so your mids aren't wasting power on bass they can't produce, and set the gain properly rather than treating it as a volume knob. Our amp tuning guide covers both in 20 minutes. Feed it with a true-gauge amp wiring kit.
Running subs only? See monoblock amplifiers instead. Need help matching an amp to your speakers? Message us with your setup.