---
product_id: 478719374
title: "Infinity Alpha 121W Single Voice Coil Subwoofer (Black)"
brand: "infinity"
price: "¥18379"
currency: JPY
in_stock: true
url: https://www.desertcart.jp/products/478719374-infinity-alpha-121w-single-voice-coil-subwoofer-black
store_origin: JP
region: Japan
---

# 1800W peak power punch Waterproof for any ride 12" powerful driver Infinity Alpha 121W Single Voice Coil Subwoofer (Black)

**Brand:** infinity
**Price:** ¥18379
**Availability:** ✅ In Stock

## Summary

> 🎶 Drive the vibe, own the bass.

## Quick Answers

- **What is this?** Infinity Alpha 121W Single Voice Coil Subwoofer (Black) by infinity
- **How much does it cost?** ¥18379 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.jp](https://www.desertcart.jp/products/478719374-infinity-alpha-121w-single-voice-coil-subwoofer-black)

## Best For

- infinity enthusiasts

## Why This Product

- Trusted infinity brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **1800 Watts Peak Power:** Unleash thunderous bass that commands attention on every drive.
- • **Bass Boost Technology:** Elevate your audio experience with enhanced low-frequency performance.
- • **Waterproof Durability:** Engineered to withstand moisture, perfect for adventurous lifestyles.
- • **Seamless Compatibility:** Effortlessly pairs with car stereos and smartphones for ultimate convenience.
- • **Deep 12-Inch Bass Driver:** Feel every beat with a robust single voice coil subwoofer designed for immersive sound.

## Overview

The Infinity Alpha 121W is a 12-inch single voice coil subwoofer delivering 1800 watts peak and 250 watts RMS power. With a 4-ohm impedance and 89dB sensitivity, it offers powerful, clear bass. Waterproof and compatible with car stereos and smartphones, it features bass boost technology for an enhanced audio experience, making it a perfect upgrade for any vehicle audio system.

## Description

Full description not available

## Features

- 12" Single Voice Coil Subwoofer, Peak Power 1800 Watts, RMS Power 250 Watts
- RMS Power: 250 W
- Impedance: 4 ohm
- Sensitivity (2.83V/m): 89dB
- Is Waterproof: True

## Technical Specifications

| Specification | Value |
|---------------|-------|
| Mounting Type | Flush Mount |
| Material | other |
| Model Name | 121W |
| Speaker Type | Subwoofer |
| Special Feature | Bass Boost |
| Recommended Uses For Product | Styling |
| Compatible Devices | Car Stereo, Smartphone |
| Subwoofer Diameter | 12 Inches |
| Surround Sound Channel Configuration | 1 |
| Colour | Black |
| Included Components | Subwoofer, Installation Manual and Warranty Card |
| Product Dimensions | 77D x 20W x 31H Centimeters |
| Item Weight | 3600 Grams |
| Impedance | 4 Ohm |
| Is Waterproof | True |
| Warranty Type | Limited |
| Number of Items | 1 |
| Control Method | Voice |
| Wireless Communication Technology | Bluetooth |
| Speaker Size | 12 Inches |
| Power Source | Battery Powered |
| Woofer Diameter | 12 Inches |
| Tweeter Diameter | 1 Inches |
| Water Resistance Level | Waterproof |
| Audio Driver Size | 12 Inches |
| Subwoofer Connectivity Technology | Wireless |
| Manufacturer | HARMAN INTERNATIONAL, Harman International (India) Pvt Ltd, Prestige Technology Park, 4th Floor, Jupiter 2A, Marathahalli Ring Rd, Bangalore 560103, India, Customer Care 18001020525 |
| Model | ALPHA |
| Item model number | ALPHA |
| Special Features | Bass Boost |
| Speakers Nominal Output Power | 250 Watts |
| Noise Level | 89 Decibels |
| Speaker amplification type | Passive |
| Speaker connectivity | Wired |
| Wattage | 1800 Watts |
| Batteries Included | No |
| Batteries Required | No |
| Includes Rechargeable Battery | No |
| Manufacturer | HARMAN INTERNATIONAL |
| Item Weight | 3 kg 600 g |

## Product Details

- **Brand:** Infinity
- **Speaker Maximum Output Power:** 1800 Watts
- **Frequency Response:** 35 Hz
- **Connectivity Technology:** wired
- **Audio Output Mode:** Surround

## Images

![Infinity Alpha 121W Single Voice Coil Subwoofer (Black) - Image 1](https://m.media-amazon.com/images/I/61vNkpCzQyL.jpg)
![Infinity Alpha 121W Single Voice Coil Subwoofer (Black) - Image 2](https://m.media-amazon.com/images/I/51P8k9tsmXL.jpg)

## Questions & Answers

**Q: Can i use this subwoofer for Home theatre**
A: Yes, I am using it for my home theatre only. But to get a good bass you need to hook up a powerful amplifier. If your idea is to connect this to your AV Receiver (with a Passive Sub output), then I wouldn't recommend this. Hope it helps. Thank You.

**Q: Is it safe to connect this to 220w amplifier or will there be any issues to amplifier and speaker? Please reply**
A: Yes, I am using this for my Home Theatre with Dayton 250W Plate Amplifier. Getting a very good Bass.
Thank You.

**Q: I want to put 2 of this subwoofers in my swift vdi which amp should i use?**
A: Infinity Alpha 2804A

**Q: What are the dimensions exactly and what is the difference in this and infinity refrence 1200s??**
A: 12 inch subwoofer.
Reference is high power, this is lower in power.

## Frequently Bought Together

- Infinity Alpha 121W Single Voice Coil Subwoofer (Black)
- BOSS AUDIO RCA KIT2 8 Gauge Installation Wiring Kit For Amplifier, Multicolor
- Kicker 46KISLOC2 K-Series Stereo Line-Output Converter w/Remote Turn-On Output

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**Shop now:** [https://www.desertcart.jp/products/478719374-infinity-alpha-121w-single-voice-coil-subwoofer-black](https://www.desertcart.jp/products/478719374-infinity-alpha-121w-single-voice-coil-subwoofer-black)

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*Product available on Desertcart Japan*
*Store origin: JP*
*Last updated: 2026-03-18*