--- product_id: 58115674 title: "M04 Subwoofer Amplifier for Home Theater Mono Channel Digital Class D Integrated Power Amp for Passive Speakers Subwoofer" brand: "fosi audio" price: "KD 26.30" currency: KWD in_stock: true reviews_count: 13 category: "Fosi Audio" url: https://www.desertcart.com.kw/products/58115674-m04-subwoofer-amplifier-for-home-theater-mono-channel-digital-class store_origin: KW region: Kuwait --- # 100W output power Cool-running Class D tech Bass & frequency control M04 Subwoofer Amplifier for Home Theater Mono Channel Digital Class D Integrated Power Amp for Passive Speakers Subwoofer **Brand:** fosi audio **Price:** KD 26.30 **Availability:** ✅ In Stock ## Summary > 🎵 Elevate your bass game with the Fosi M04 — small amp, massive impact! ## Quick Answers - **What is this?** M04 Subwoofer Amplifier for Home Theater Mono Channel Digital Class D Integrated Power Amp for Passive Speakers Subwoofer by fosi audio - **How much does it cost?** KD 26.30 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.com.kw](https://www.desertcart.com.kw/products/58115674-m04-subwoofer-amplifier-for-home-theater-mono-channel-digital-class) ## Best For - fosi audio enthusiasts ## Why This Product - Trusted fosi audio brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Powerful 100W Output:** Drive your passive subwoofer with crystal-clear, room-shaking bass that commands attention. - • **Compact & Sleek Design:** Fits seamlessly into any home theater setup without sacrificing style or space. - • **Precision Bass Control:** Switch effortlessly between subwoofer and full-range modes for tailored soundscapes. - • **Plug & Play Convenience:** Complete package with power supply and easy bare-wire connections—upgrade your sound instantly. - • **Whisper-Quiet Operation:** Enjoy deep, thunderous bass without distracting noise or overheating. ## Overview The Fosi Audio M04 is a compact, high-performance mono subwoofer amplifier delivering 100 watts of clean power via Class D technology. Designed for passive subwoofers, it features adjustable bass modes, a built-in low pass filter, and a robust yet sleek enclosure. Ideal for home theater enthusiasts seeking affordable, powerful, and noise-free bass enhancement. ## Description Product description Fosi Audio M04 Subwoofer Amplifier SNR: ≥ 102dB; THD: ≤ 0.02% (1KHz, 1W) Max Power Output: 100watt @2Ω Drive Your Bookshlef Speaker Fill your device with the throbbing bass beats you want. Drive Your Subwoofer Speaker Play low frequencies without distortion, and provide enough clean power. Sub Freq & Volume Control Fine tunes the volume level signal you wish to control. Fit Almost Anywhere Improving the bass and the power of your music. Texas Instruments TPA3116 Chip Wide voltage input range and high efficiency. Switching Between Modes There is a switch for changing modes on the subwoofer amplifier M04. PBTL defines it as a Full-Frequency Mono amp for driving passive speakers. To SUB, it's a subwoofer amplifier used with passive subwoofers. DIY Your Audio System Creating a professional sound system is easy with this mono amplifier. You can use this amp to drive most bookshelf speakers or subwoofers in your home. Fosi Audio Subwoofer Amp Subwoofer/Mono Amp M04 MAX Power Output 100W Input RCA THD ≤ 0.02% SNR ≥ 102dB Power Adapter 19V/4.74A Bluetooth Learn More Subwoofer/Mono Amp M04 MAX Power Output 100W Input RCA THD ≤ 0.02% SNR ≥ 102dB Power Adapter 19V/4.74A Bluetooth Subwoofer/Mono Amp M01-BT MAX Power Output 220W Input Bluetooth + RCA THD ≤ 0.05% SNR ≥ 102dB Power Adapter 24V/4.5A Bluetooth Learn More Subwoofer/Mono Amp M01-BT 220W Bluetooth + RCA ≤ 0.05% 24V/4.5A Subwoofer/Mono Amp M03 MAX Power Output 200W Input RCA THD ≤0.03% SNR ≥106dB Power Adapter 32V/5A Bluetooth Learn More Subwoofer/Mono Amp M03 200W ≤0.03% ≥106dB 32V/5A Subwoofer Amp TP-02 MAX Power Output 220W Input RCA THD ≤ 0.04% SNR ≥ 98dB Power Adapter 24V/4.5A Bluetooth Learn More Subwoofer Amp TP-02 ≤ 0.04% ≥ 98dB Review: Great little subwoofer AMP - Got this subwoofer amp to bypass the amp component of my active subwoofer which died months ago due to a peak in voltage. My amp was those that work in "stand-by" mode, so they are always powered up somehow. Replacing the board with a new one (original) was too expensive, even more expensive than what the sub costed me in the first place, so in order to not throw the box and the woofer cone to the trash, I decided to just rewire things up in order to bypass the sub's integrated amp, so I got this GREAT little FOSI amp to power my "now passive" sub. Things worked great and my sub is now back to life, shining again. The M04 Fosi Amp is a great choice as it is POWERFUL, noiseless (at least to my ear), very small and does not generate any important heat. It comes with a power adapter, so you only need the cables to connect the input signal and the output signal to the passive subwoofer. I used the convenient "bare wire connection" to hook the modified sub to the speaker output of the Fosi Amp. Worked NICELY. Quality of the M04 Fosi AMP is VERY GOOD, in a very neat, compact and ellegant BLACK enclosure. It is definitely worth the money, which is NOT AT ALL expensive, but quality exceeds by far the amount paid for this amp. Until now, i'm really loving it. Review: Does the job. Quality feels escellent - Works perfectly. My use case doesn't push it so can't comment on the power, but it sounds good to me and does the job it is intended for. ## Features - High-Performance Mono Amplifier:The Fosi Audio M04 is a mono amplifier designed for driving passive subwoofers or speakers. It features the Texas Instruments TPA3116 chip and NE5532 op-amp, providing an output power of 100 watts for a 2-ohm subwoofer or speaker. - Enhanced Bass Response:The M04 SUB amp is designed to improve the bass response of passive subwoofers. It features a selector switch that allows the user to switch between subwoofer bass amplifier and full-frequency mono amplifier modes. - Compact and Robust Design:This mini amp has a small and robust design with a built-in low pass filter for subwoofers and a sub frequency control, making it practical and powerful. It uses highly efficient Class D technology that remains cool under demanding loads and doesn't take up much space. - Superior Sound Quality:The home subwoofer amplifier can produce a deep, crisp, and clean low-frequency sound effect, making it an excellent addition to dedicated home audio receivers & amplifiers. It has been designed to enhance the sound and performance of your audio system at an affordable price. - Complete Package:What You Get: M04 subwoofer amp x1, 19V/4.74A power supply x1, user manual x1. ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B07942M4MC | | Best Sellers Rank | #11,558 in Electronics ( See Top 100 in Electronics ) #53 in Audio Component Amplifiers | | Brand Name | Fosi Audio | | Customer Reviews | 4.4 out of 5 stars 513 Reviews | | Included Components | Fosi Audio M04 | | Item Dimensions | 5.2 x 3.5 x 1.4 inches | | Item Weight | 450 Grams | | Item dimensions L x W x H | 5.2 x 3.5 x 1.4 inches | | Manufacturer | Fosi Audio | | Maximum Supply Voltage | 19 Volts (DC) | | Minimum Supply Voltage | 19 Volts (DC) | | Model | M04 | | Mounting Type | Freestanding | | Number of Channels | 1 | | Output Power | 100 Watts | | Part Number | M04 | | Specification Met | [Inf] Thd <= 0.04% and Frequency Range 20hz - 120hz | | Unit Count | 1.0 Count | | Voltage | 12 Volts (DC) | | Warranty Description | 18-month manufacturer | ## Product Details - **Item dimensions L x W x H:** 5.2 x 3.5 x 1.4 inches - **Manufacturer:** Fosi Audio - **Maximum Supply Voltage:** 19 Volts (DC) - **Minimum Supply Voltage:** 19 Volts (DC) - **Voltage:** 12 Volts (DC) ## Images ![M04 Subwoofer Amplifier for Home Theater Mono Channel Digital Class D Integrated Power Amp for Passive Speakers Subwoofer - Image 1](https://m.media-amazon.com/images/I/51ghuLx4kZL.jpg) ![M04 Subwoofer Amplifier for Home Theater Mono Channel Digital Class D Integrated Power Amp for Passive Speakers Subwoofer - Image 2](https://m.media-amazon.com/images/I/61Ak0UXz-9L.jpg) ![M04 Subwoofer Amplifier for Home Theater Mono Channel Digital Class D Integrated Power Amp for Passive Speakers Subwoofer - Image 3](https://m.media-amazon.com/images/I/71wr-HQ6BrL.jpg) ![M04 Subwoofer Amplifier for Home Theater Mono Channel Digital Class D Integrated Power Amp for Passive Speakers Subwoofer - Image 4](https://m.media-amazon.com/images/I/61wiAu6j8pL.jpg) ![M04 Subwoofer Amplifier for Home Theater Mono Channel Digital Class D Integrated Power Amp for Passive Speakers Subwoofer - Image 5](https://m.media-amazon.com/images/I/71Gs1A+QKpL.jpg) ## Questions & Answers **Q: Will this power up passive subwoofers ?** A: Yes, absolutely. That's the reason I bought it and it works just fine without spending a whole lot of money. **Q: How hot does this amp run? The unit I currently use is very hot to the touch even after a short while.** A: This thing seems cool no issues **Q: What is the input voltage range?** A: Not sure what your question is about. If you mean input power, it's spec'd. at 12-24 vdc. It comes with a power brick rated at 19 vdc, 4.47 amps. Input sensitivity is =< 280 mv... **Q: I have a Harman Kardon reciver with a single rca sub connection. What cables do i need to hook my sub to this amp and the amp to my reciever** A: You need 1/8 audio plug to RCA adapter .. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Great little subwoofer AMP *by A***M on February 16, 2024* Got this subwoofer amp to bypass the amp component of my active subwoofer which died months ago due to a peak in voltage. My amp was those that work in "stand-by" mode, so they are always powered up somehow. Replacing the board with a new one (original) was too expensive, even more expensive than what the sub costed me in the first place, so in order to not throw the box and the woofer cone to the trash, I decided to just rewire things up in order to bypass the sub's integrated amp, so I got this GREAT little FOSI amp to power my "now passive" sub. Things worked great and my sub is now back to life, shining again. The M04 Fosi Amp is a great choice as it is POWERFUL, noiseless (at least to my ear), very small and does not generate any important heat. It comes with a power adapter, so you only need the cables to connect the input signal and the output signal to the passive subwoofer. I used the convenient "bare wire connection" to hook the modified sub to the speaker output of the Fosi Amp. Worked NICELY. Quality of the M04 Fosi AMP is VERY GOOD, in a very neat, compact and ellegant BLACK enclosure. It is definitely worth the money, which is NOT AT ALL expensive, but quality exceeds by far the amount paid for this amp. Until now, i'm really loving it. ### ⭐⭐⭐⭐⭐ Does the job. Quality feels escellent *by R***E on May 7, 2026* Works perfectly. My use case doesn't push it so can't comment on the power, but it sounds good to me and does the job it is intended for. ### ⭐⭐⭐⭐ Not LFE’s best friend. Good with speaker level input. *by J***E on March 12, 2026* Had two of these for a short while now. I’ve tried my setup a few ways. If you have 4ohm speakers, this won’t push much when connected to an LFE. However, if you use speaker level output (by wiring into an rca jack), this will push plenty of sound. It’s frustrating because I want to use my receivers LFE, but cannot because little sound is achieved in that setup. The switch from full-range to sub works great. The frequency dial would be better if it had hz dial markers (around 1/2 way is close to 80hz). The volume does what it should just fine. Build quality is great. Only issue is the line-level input gets me barely any sound on the 4ohm speaker. (6.5” passive woofers in a sub enclosure which is easily getting down below 35hz.) ## Frequently Bought Together - Fosi Audio M04 Subwoofer Amplifier for Home Theater Mono Channel Digital Class D Integrated Power Amp for Passive Speakers Subwoofer - FosPower RCA Y-Adapter (3 Feet), 1 RCA Male to 2 RCA Male Short Y Splitter Digital Stereo Audio Cable for Subwoofer, Home Theater, Hi-Fi - Dual Shielded | 24K Gold Plated - Tan QY 2RCA to 2RCA Cable 3Ft, Gold-Plated 2 RCA Male to 2 RCA Male Stereo Audio Cable for Home Theater, HDTV, Gaming Consoles, Hi-Fi Systems (3Ft/1M) --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.com.kw/products/58115674-m04-subwoofer-amplifier-for-home-theater-mono-channel-digital-class](https://www.desertcart.com.kw/products/58115674-m04-subwoofer-amplifier-for-home-theater-mono-channel-digital-class) --- *Product available on Desertcart Kuwait* *Store origin: KW* *Last updated: 2026-05-15*