Clean lines and solid power

German engineering and craftsmanship combine to create a sleek amplifier that'll make your vehicle come alive with big bass. The Helix Blue B ONE mono amp will put out 350 watts RMS to a 4-ohm sub, 600 watts RMS to a 2-ohm sub, or a whopping 950 watts RMS to a 1-ohm subwoofer system, so you can be sure you'll always have plenty of power, whatever kind of system you have.

Made for high quality sound

The Helix Blue B ONE amp starts with a noise-free input stage, then uses proprietary technology to achieve an incredible level of acoustic accuracy. The attention to detail extends down to the superior internal components, specially "surface-mounted" to double-sided, copper-plated circuit boards, all contributing to superb sound quality. A big, heavy wrap-around heatsink dissipates the heat for cool, reliable play.

B ONE features

You'll find the tools you need to shape your bass. You can adjust the low-pass and subsonic filters to get maximum production from your enclosure and the best possible bass tone in your ride. A bass boost will add even more bang, if you want it to. And a remote level controller is included so you can dial in the right amount of bass from the front seat.

Bass amp for a Helix factory upgrade system

The B ONE can also serve as the sub amp in a Helix Plug and Play factory upgrade system.

  • You can use an EPC5 Easy Plug Cable and a Helix vehicle-specific adapter harness to plug your B ONE directly into your vehicle's stereo to get its input signal, with no wire-cutting or splicing necessary.
  • Or, if you're using the PP50DSP processor/amplifier and want more bass, you can get a PP-SC4 cable to directly connect it to the B ONE's input.
It's a great way to add serious bass to a leased vehicle or any vehicle with a hard-to-replace factory radio.

Product Highlights:

  • mono subwoofer amplifier
  • 350 watts RMS x 1 at 4 ohms (600 watts x 1 at 2 ohms)
  • 950 watts RMS x 1 at 1 ohm
  • Class D design
  • variable low-pass filter (35-200 Hz)
  • variable subsonic filter (15-50 Hz)
  • bass boost (0-18 dB at 45 Hz )
  • wired remote bass level control included
  • speaker-level inputs via 8-pin harness
  • preamp inputs and outputs
  • 4-gauge power and ground leads recommended — wiring and hardware not included with amplifier
  • fuse rating: 30A x 3
  • 14"W x 2"H x 10-1/4"D
  • warranty: 2 years
  • Our 60-day money-back guarantee

My system has plenty of power. Who needs an amp?

You might think you don't need an amp because you have a 400-watt system in your car, or because your new stereo puts out 50 watts a channel. But those are peak wattage ratings, which may boil down to 15 or 20 watts per channel, using the more realistic RMS rating. An amp sends your speakers the power they need to deliver your music with clarity and impact, whether you're using factory speakers or high-performance components. And low-frequency reproduction requires lots of power, so an amp is an absolute must if you're adding a sub to your system.

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Hands-on research

What's in the box?

Download owner's manual

  • Mono subwoofer amplifier
  • Three 30 amp ATO fuses (installed)
  • Wired remote control
  • 16.5' Remote cable (RJ-25 plug on both ends)
  • Four 3/4" Self-tapping screws
  • Two 1/2" Screws
  • 8" Speaker-level input harness (Molex plug on one end)
  • 4mm Allen wrench
  • 2mm Allen wrench
  • Instruction manual (German/ English)

Product Research



1-Ohm Stable: The B ONE is stable down to 1-ohm. The 2-ohm output is 600 Watts RMS x 1 channel and the 1-ohm output is 950 Watts RMS x 1 channel.

Protection Circuitry: The B ONE offers four protection circuits: short circuit (or too low an impedance on the outputs), thermal overload, over voltage, and under voltage.

Multiple Amplifiers: Two identical B ONE amplifiers can be strapped together to double the power to a single subwoofer. When used in this configuration one amp is the master (controls gain, crossover point, subsonic filter, and bass boost), and the other the slave.

Wired Remote: The amplifier includes a wired remote control; the remote allows you to control the output level of the amplifier from the dash or center console of your vehicle. The remote features a rotary dial and comes with mounting hardware and a 16.5' connector cable, with RJ-25 phone plugs at each end.


Crossover: The built-in low pass crossover is always active. The crossover point is continuously variable from 35 to 250 Hz.

SubSonic Filter: The subsonic filter is designed to prevent frequencies below the audible range (or below the range the subwoofer can reproduce) from being delivered to the subwoofer. The subsonic crossover point is continuously variable from 15 to 50 Hz.

Gain: The rotary gain control is continuously variable from 0.2 volts to 6.0 volts to match the source signal.

Bass Boost: The bass boost circuit is centered at 45 Hz and continuously variable from 0 dB to +18 dB.

Master/Slave: Choose the master or slave mode if using two B ONE amplifiers together to power one subwoofer. The master setting is used when not strapping two amps together.


Power: The power and ground inputs are set-screw terminals; they will accept bare wire up to 4-gauge (HELIX recommends 4-gauge minimum) and are tightened/loosened with the supplied 4mm Allen wrench.

Remote: The remote turn-on input is a set screw terminal; it will accept bare wire up to 10-gauge and is tightened/loosened with the supplied 2mm Allen wrench.

Speaker Outputs: There are two pair of set-screw speaker terminals, internally wired in parallel so you can easily connect two subwoofers. The terminals accept bare wire up to 10-gauge and are tightened/loosened with the supplied 2mm Allen wrench.

Line Input: Stereo RCA jacks connect to the output signal from the head unit.

Speaker Level Input: Use the included harness when speaker level inputs are needed, or use the HELIX Easy Plug Cable and vehicle specific adapter harness (both sold separately, see explanation above).

Note: The included speaker level input harness doesn't use the standard aftermarket color codes, and there's no color key in the manual (although the pin positions are labeled on the side of the amp). The colors used are:
  • Gray: channel 1 negative
  • Red: channel 1 positive
  • White: channel 2 negative
  • Blue: channel 2 positive

Line Output: Stereo RCA output jacks make adding another amplifier easy. The settings on the built-in crossover and subsonic filter have no effect on the line outputs.

Master Output: A single RCA jack supplies the audio signal to another B ONE amplifier when two are strapped together to power one subwoofer.

Slave Input: A single RCA jack serves as the input when two B ONE amplifiers are strapped together to power one subwoofer.

Fuse: The amp is protected by three 30-amp ATO-type fuses.

Our Product Research Team

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