Product overview
Experience your music in Hi-Res with the R-A90S 6-channel R-Series amplifier. This is one of the most versatile Class-D 6-channel amplifiers on the market, featuring a unique staggered power channel layout that has double the power on the last two channels, as well as built-in high-pass and low-pass filters to build any kind of sound system.
The “R” line of speakers and subwoofers have a heritage of sound quality you can hear from a block away, and the newly added R-Series amplifiers are no exception. Aside from their best-in-class performance, these amplifiers are tuned to emphasize the characteristics of the R-Series speakers and subwoofers, giving you that legendary R-Series experience.
The R-Series lineup is “The Loudest Family on the Block”. The products are designed to be played loud, delivering a fun and exciting listening experience, and are known for dependable performance and high-quality sound. All R-Series components are developed to perfectly match each other.
With double the power on the last two channels, the R-A90’s 5th and 6th channels can be bridged to provide up to 500 Watts RMS @ 4 Ohms to your subwoofer system. The R-A90S has a unique staggered power channel layout, that has double the power on the last two channels. This means you can set the amp to deliver 4x 75 Watts + 2x 150 Watts to run 2 separate subs, or configure it 4x 75 Watts + 1x 500 Watts to run one very powerful subwoofer.
Thanks to the unique staggered power channel layout, the R-A90S can host different levels of power on each channel, compared to traditional multi-channel amplifiers. The R-A90S can effectively function as both a 3-way active amplifier and a 5-channel amplifier by delivering the power you need to the channels where you need the most.
Hear the subtle details you’ve been missing in your music. The R-A90S maintains an extremely low phase shift throughout the music spectrum, which minimizes audible imperfections in your music and allows your music to stay faithful to the original recording. With a hi-resolution frequency response, the R-A90S can reproduce sound with incredible accuracy that stays true to the artist’s intention.
Using custom Alpine internal components originally launched in Alpine’s premium X-Series amplifiers, the R-A90S has dual “Sierra” post-filter feedback loops that correct signal distortion by making the output as close as possible to the original input for accurate sound reproduction
Key features
- Small footprint for easy installation
- Screw terminals (for speaker and power cables)
- Thermal Management Control
- Top Mounted LED Power/Status Indicator
- Speaker Level Input with remote turn on
- Bass EQ
- Remote Bass Control ( RUX-KNOB2 ) Ready
- High Level Input with automatic power on
Technical specifications
| Install | |
|---|---|
| Terminal Layout | One side |
| General | |
| Amplifier Type | Class-D (Digital) |
| Channel Design | 6/5/4/3 Channel Design with Ch 5 + 6 Power Stagger Feature |
| Crossover | Adjustable Low-pass (LPF), High-Pass Filter (HPF) and Band-Pass Filter |
| Gain Control | Adjustable |
| Max Power Output Ratings | |
| Total Max Power | 1800W |
| RMS Power Ratings | |
| Per Channel into 2 Ohms, 14.4V (≤1%THD+N) | 4 x 100W + 2 x 250W |
| Per Channel into 4 Ohms, 14.4V (≤1%THD+N) | 4 x 75W + 2 x 150W |
| Per Channel into 4 Ohms, 14.4V (≤1%THD+N) | 4 x 75W + 1 x 500W (bridged) |
| Per Channel into 4 Ohms, 14.4V (≤1%THD+N) | 2 x 150W + 1 x 500W (bridged) |
| Sound Tuning | |
| Variable HPF/HPF-H | 50Hz – 400Hz / 400Hz – 6kHz |
| LPF | 50Hz – 400Hz |
| BPF-L / BPF-H | 50Hz – 400Hz / 400Hz – 6kHz |
| General | |
| Power Requirements | 14.4 V.DC (9 – 16 V allowable) |
| Input Sensitivity (RCA Input) | Hi: 0.5V – 10V / Low: 0.2V – 4.0V |
| Cable size | Power Cable AWG 4, SPK Cable AWG 8 |
| Frequency Response (+0/ -3dB | 1W into 4 Ohms): 10Hz – 45kHz |
| THD+N (@ 10W into 4 Ohms) | <0.02% |
| THD+N rated power into 4 Ohms) | <0.03% |
| Damping Factor | >500 (ref. 10W into 4 Ohms at 100Hz) |
| Signal to Noise (rated power into 4 Ohms) | >103dB (Ch 1-4) / >106dB (Ch 5+6) |
| Weight | 4.52kg |
| Dimensions | |
| Heat Sink (WxHxD) mm | 273 x 50.8 x 200 |
| With attached brackets (WxHxD) mm | 273 x 50.8 x 324 |
What you are ordering
The exact Alpine model shown above, SKU R-A90S. Confirm vehicle compatibility for installation kits, interfaces and vehicle-specific systems before checkout.
Product information verified against the official Alpine product page.