3-Inch Full-Range Audio Speaker - 4 Ohm, 5W with Blue Cone

Specifications

• Nominal Size: 3 Inch (75mm outer frame width)

• Impedance: 4 Ohms (4Ω)

• Power Rating: 5 Watts (5W)

• Frequency Response: Full-Range

• Mounting Hole Diagonal Distance: 85mm

• Total Mounting Depth: 34mm

• Connection Type: Solder Eyelet Tabs (+ / - marked)

• Frame Material: Stamped Metal

Key Applications and Projects

• DIY Bluetooth Speakers: Pairing two of these speakers with a Bluetooth amplifier board to create a custom, portable, battery-powered boombox.

• Retro Arcade Cabinets: Replacing blown or scratchy speakers in bar-top arcade machines (like Raspberry Pi RetroPie builds) for loud, clear gaming sound.

• Interactive Robotics: Giving your Arduino or ESP32 robot a "voice" by combining this speaker with a DFPlayer Mini MP3 module.

Unlock New Capabilities (Project Evolution)

• The Smart WiFi Internet Radio: Why stop at Bluetooth? Evolve your audio projects! Build a custom wooden enclosure for this speaker. Inside, mount an ESP32 microcontroller paired with an I2S DAC (Digital-to-Analogue Converter) and a MAX98357A amplifier. Program the ESP32 to connect to your home WiFi and stream global internet radio stations directly from the web! You will have a standalone, vintage-style smart radio with surprisingly robust sound.

Package Includes:

• 1 x 3-Inch 4 Ohm 5W Full-Range Audio Speaker

FREQUENTLY ASKED QUESTIONS (FAQ)

1. What is the impedance of this speaker? It has an impedance of 4 Ohms, clearly stamped on the rear magnet.

2. What is the maximum power rating? It is rated for 5 Watts of audio power.

3. What does "full-range" mean? It means the single speaker is designed to produce low, mid, and high frequencies adequately, rather than focusing on just bass (subwoofer) or just treble (tweeter).

4. Is this a single speaker or a pair? The listing is for a single (1x) speaker unit.

5. How do I wire this to an amplifier? There are two metal solder tabs on the back of the speaker attached to a red strip. You must solder your positive and negative audio wires directly to the holes in these tabs.

6. Does polarity matter? (+ and -) Yes. While hooking it up backward will not explode the speaker, it will cause the cone to move inward instead of outward, placing the audio "out of phase," which severely ruins bass response. Follow the + and - markings on the red terminal strip.

7. What are the exact physical dimensions? The square-ish metal frame is roughly 75mm wide, the diagonal distance between the mounting holes is 85mm, and the depth is 34mm.

8. Will this work with a PAM8403 5V amplifier? Yes, this is the most highly recommended speaker pairing for a PAM8403 3W amplifier board.

9. Can I connect this directly to an Arduino without an amplifier? No. Microcontrollers output very weak logic-level signals. You must route the signal through an amplifier module (like an LM386) before connecting it to this speaker, otherwise, it will be incredibly quiet and may damage the Arduino.

10. Is this speaker waterproof? No. The blue cone is made of treated material, but it will warp and degrade if exposed to rain or direct water. It is intended for indoor use.

11. Do I need to build an enclosure/box for it? Yes. A raw speaker played in open air lacks bass because the sound waves from the front and back cancel each other out. Putting it in a sealed or ported box drastically improves audio quality and bass response.

12. Can I use a 10W amplifier on a 5W speaker? Yes, but you must be careful with the volume knob. If you turn a 10W amp to maximum volume, it will push too much power into this speaker and physically tear the cone or burn out the voice coil.

13. Are mounting screws included? No, mounting hardware is not included. You will need four standard wood screws or machine bolts to mount the frame.

14. What is the magnet made of? It is a standard permanent ferrite ring magnet.

15. Does it come with a protective grill? No, this is a bare speaker driver designed to be mounted from the inside of your custom enclosure.

16. Can I connect two of these to one amplifier channel? You can, but you must understand impedance. Connecting two 4 Ohm speakers in series creates an 8 Ohm load. Connecting them in parallel creates a 2 Ohm load, which can overheat and destroy many small amplifiers.

17. Can I use this in my car? Technically yes, if connected to a suitable car radio output, but 5 Watts is extremely low power for automotive audio. It is much better suited for desktop electronics.

18. Why does it sound "tinny" or "scratchy"? Tinny audio usually means the speaker is not inside a sealed enclosure. Scratchy audio means your amplifier is clipping (distorting) because it lacks enough power/voltage, or the speaker cone has been physically dented.

19. What is the black dome in the center? That is the dust cap. It prevents dirt and metal shavings from falling into the delicate magnetic voice coil gap.

20. Can I push the center dust cap in? No! Pressing on the center dome will dent or crush it, which can permanently ruin the high-frequency acoustics of the speaker.