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The ESB 4.165 is a 6.5 inch (165 mm) component mid-woofer from ESB Audio's 4000 Series, rated at 150W RMS (300W transient) at 4 ohms and sold as a pair. Key construction features include a die-cast aluminium basket, Y35 ferrite motor and long-fibre pulp cone.
The matching 4000 Series tweeter is the ESB 4.28 silk dome tweeter. For a complete 3-way component system in the same size, see the ESB 8.6K3 Ottomila Series 6.5 inch 3-way component system.
Key specifications
- Size: 6.5 inch / 165 mm
- Power handling: 150W RMS / 300W transient
- Impedance: 4 ohm
- Frequency response: 50 Hz to 6 kHz
- Sensitivity: 92.5 dB (2.83V/1m)
- Magnet: Y35 ferrite, FEA-optimised
- Basket: die-cast aluminium alloy
- Cone: long-fibre unbleached pulp, nitrile rubber surround
- Grille: stainless steel
4.165 6.5"/165 mm Mid-Woofer
The pole piece is ultra-low carbon alloy steel, CNC-machined using FEM magnet analysis software and cold forged in one piece for precise geometry. This concentrates magnetic force directly in front of the voice coil.
The Y35 ferrite magnet motor is FEA-optimised for symmetrical magnetic flux in both directions of cone travel. Motor metal parts are CNC-machined from solid refined material to maximise flux linearity, minimise magnetic loss and reduce distortion at high power.
The die-cast aluminium alloy basket is rigid with minimal airflow resistance. Casting follows strict procedures to ensure regulatory compliance and consistent quality.
The CNC-machined ultra-low carbon alloy steel pole plate is precision-flat, sitting flush over the magnet without reducing magnetic flux.
The large aluminium copper-clad vented voice coil handles high power while maintaining dynamic, realistic music reproduction. The copper-clad aluminium wire is lightweight with excellent heat dissipation.
The cone uses long-fibre unbleached pulp with a special external treatment, combining lightness, rigidity and internal damping.
The nitrile rubber surround is UV-resistant and unaffected by temperature change, preserving acoustic performance long-term. Its edge design allows free forward and backward movement.
Supplied with a deluxe protective stainless-steel grille.
Explore the full range in ESB 4000 & Cinquemila.
Specification
| Nominal Impedance | 4 Ohm |
|---|---|
| Nominal Power Handling | 150 Watt |
| Transient Power | 300 Watt |
| Frequency Response | 50 Hz ~ 6 KHz |
| Sensitivity | 92.5 dB 2.83v/1m |
What's Included
- ESB 4.165
ESB Audio
About the ESB Audio 4.165
From our tech experts at CEN
The ESB 4.165 is a pair of 6.5 inch (165mm) mid-woofers from ESB's 4000 Series, sold without tweeters. Each handles 150w RMS and 300w transient at 4 ohm, with 92.5 dB sensitivity and a 50 Hz to 6 kHz range. It uses a die-cast aluminium basket, an FEA-optimised Y35 ferrite motor and a long-fibre pulp cone.
Who it suits
Active and component builds that want more control and power handling than the Tremila mid-woofer. The matching 4000 Series tweeter is the 4.28, and the 4.100 or 4.75 midranges complete a 3-way front stage.
Our tech experts advise
With a 6 kHz upper limit it should be crossed to a tweeter well below that, ideally with a processor. Give it its own amplifier channel and a solid baffle, and treat the door. Installation is priced per vehicle, so get in touch with your make, model and year.
Explore the full ESB Audio range at CEN, with fast UK dispatch and expert advice from our Nottingham team. Shop all ESB Audio
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Have it Fitted By Our Team
Our team fits car audio, stereos, dash cams and vehicle security at our workshop in Beeston, Nottingham. Tell us your vehicle and we'll confirm the parts and a fitted price.
- 1
Tell us your vehicle
Make, model and year, and what you'd like fitted.
- 2
We confirm the parts
Fascia, wiring and interfaces checked for your car, with a fitted price.
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Fitted at our workshop
Bring it to our Beeston workshop and we do the rest.
Unit 25 Technology Drive, Beeston, Nottingham NG9 1LA
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Frequently Asked Questions
Q: Will these speakers fit my car?
A: Most car speakers are standard sizes, but mounting depth and fitting rings vary by vehicle. Check the size in the Specification tab against your vehicle, or contact CEN with your registration and we will confirm fitment and any adapters or fitting kits you need.
Q: Do I need an amplifier to run these speakers?
A: Not always. Most speakers will run from a standard head unit, but a dedicated amplifier lets them perform at their best, particularly for component sets and higher power handling models. The RMS figure in the Specification tab is the guide to how much clean power they can use.
Q: What is the difference between coaxial and component speakers?
A: Coaxial speakers combine the tweeter and woofer in one unit for a simple like-for-like upgrade. Component sets separate the tweeter and woofer with a crossover for better imaging and detail, and suit installs where sound quality is the priority.
Q: Do these come as a pair?
A: Unless stated otherwise, car speakers are sold in pairs. Check the product title and What's Included tab, which lists exactly what is in the box.
Q: Can CEN fit these speakers for me?
A: Yes. CEN offers professional installation from our Nottingham premises. Contact us to book an installation slot or ask for a fitting quote.
Q: What is the power rating of the ESB 4.165?
A: 150W RMS with 300W transient power, at a nominal impedance of 4 ohms.
Q: What frequency range does the ESB 4.165 cover?
A: 50 Hz to 6 kHz, with a sensitivity of 92.5 dB (2.83V/1m). As a mid-woofer it is designed to be used with a separate tweeter.
Q: Does the ESB 4.165 have a grille?
A: Yes, it has a deluxe protective stainless-steel grille.
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