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  1. Home
  2. Boston Acoustics Store
  3. Discontinued Boston Acoustics Car Audio & Electronics
  4. Discontinued Boston Acoustics Car Speakers
  5. Discontinued Boston Acoustics 4" Speakers

Discontinued Boston Acoustics 4" Speakers for your 1998 Sephia close

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Speaker Size
Refers to the size of the speaker measured in inches. Every vehicle has standard application sizes. Please use our vehicle fitment guide for your vehicle's specific speaker sizes if you do not know them.
Design
The number of individual drivers in a car speaker. Speakers with 2 drivers are known as a 2-way, and 3 drivers are known as a 3-way. Component systems are often referred to as "separates" because the tweeter is not attached to the midwoofer (main speaker driver) and mounts separately in a location such as a door post. Component systems typically come with an external crossover so you can easily adjust the high and low frequencies sent to both the midwoofer and the tweeter. Center channel speakers are great for those looking to have surround sound in their vehicle.
RMS Power Handling
The RMS power is the amount of power the speaker requires to operate safely and properly. RMS Power Handling refers to the amount of power a speaker can handle on a continuous basis. We recommend powering your speakers or subwoofer with 80%-120% of its recommended RMS rating. The RMS power handling specification is typically rated per speaker unless otherwise noted.
Peak Power Handling
Peak power handling refers to the amount of power a speaker can handle during a brief musical burst. The RMS power range figure is a much more reliable rating for determining the speaker's power requirements. The Peak power handling specification is typically rated per speaker unless otherwise noted.
Sensitivity
An efficiency or sensitivity rating tells you how effectively a speaker converts power into sound. The higher the number, the more efficient the speaker and the louder it will play with the same input power. An efficient speaker helps you maximize your available power. Most sensitivity ratings measure the speaker's output with 1 watt of input, 1 meter from the speaker. Some speakers' sensitivity is measured with 2.83 volts of input, instead of 1 watt.
  Efficiency (1w/1m) is not an accurate indicator of a subwoofer's output capability and should not be used as a comparison to other speakers or subwoofers to determine which one is "louder".
Impedance (Per Voice Coil)
The load value (in ohms) that the speakers present to the amplifier per voice coil - the amount of resistance to the current flow. This is a key specification as subs wired in parallel or low impedances can create problems with your amplifier and potentially void all warranties. We encourage you to ask our support department prior to purchase if you do not understand which impedance level will suit your application best.
Shallow Mount Installation
This means that the subwoofer/speaker is designed to be installed in areas that do not have a lot of space. Shallow mount subwoofers are typically found under a seat or behind the seat in some trucks.

Shallow mount speakers will typically have a mounting depth of 2" or less, while shallow mount subwoofers will typically have a mounting depth of 3" or less.
Tweeter Design
Designs such as cone, dome, semi-dome, balanced dome, and whizzer are most popular. Cone tweeters are simple, efficient and typically are the most reasonably priced. Dome tweeters are used in most home speakers, and provide a smoother and more accurate sound. Semi-dome design is one with a dome placed inside a cone. A Balanced dome driver is a semi-dome with equal reproduction area given the cone and dome portions of the driver. A whizzer tweeter is a separate tweeter cone driven by the voice coil of the woofer.
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You are currently viewing discontinued products.

Boston Acoustics FX4 4"

FX4-2 big DISCONTINUED
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Boston Acoustics FX4 4"

4" 2-Way Coaxial Speakers • 80W RMS • Copolymer Woofer Cone • Butyl rubber surround • 3/4" Soft Dome Tweeter

No Fit Icon Doesn't fit your Sephia

4" 2-Way Coaxial Speakers • 80W RMS • Copolymer Woofer Cone • Butyl rubber surround • 3/4" Soft Dome Tweeter

Boston Acoustics ProSeries 6.53 (Pro 6.5<sup>3</sup>)

ProSeries6.53 6-1/2" + 4" 3-way Component System (PRO6.53)

PRO6.53 big DISCONTINUED
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Boston Acoustics ProSeries 6.53 (Pro 6.5<sup>3</sup>)

ProSeries6.53 6-1/2" + 4" 3-way Component System (PRO6.53)

6-1/2" ProSeries 3-way Component System • 500W Max • 250W RMS • Copolymer cone woofer • Butyl rubber surround • Rigid die-cast aluminum basket • 4.5" Midrange • 1" Rigid aluminum dome tweeter • Gold-plated terminals

No Fit Icon Doesn't fit your Sephia

1

6-1/2" ProSeries 3-way Component System • 500W Max • 250W RMS • Copolymer cone woofer • Butyl rubber surround • Rigid die-cast aluminum basket • 4.5" Midrange • 1" Rigid aluminum dome tweeter • Gold-plated terminals

Boston Acoustics RX47

4" 2-way Car Speakers

RX47 big DISCONTINUED
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Boston Acoustics RX47

4" 2-way Car Speakers

4-inch Two-way Boston Rally Speaker System with Grills • 120 Watts Maximum Power Handling • 3/4-inch Ferrofluid-cooled Tweeter

No Fit Icon Doesn't fit your Sephia

1

4-inch Two-way Boston Rally Speaker System with Grills • 120 Watts Maximum Power Handling • 3/4-inch Ferrofluid-cooled Tweeter

Boston Acoustics SE45

4" 2-way SE Series Coaxial Car Speakers

SE45 big DISCONTINUED
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Boston Acoustics SE45

4" 2-way SE Series Coaxial Car Speakers

4" SE Series Speakers • 2-Way Car Speakers • 80W Max • 35W RMS • 4 Ohm Impedance • Copolymer Woofer Cone • Butyl Rubber Surround • 3/4" TypeS3 Carbon Injected Polymer Soft Dome Tweeter with Neodymium Magnet

No Fit Icon Doesn't fit your Sephia

1

4" SE Series Speakers • 2-Way Car Speakers • 80W Max • 35W RMS • 4 Ohm Impedance • Copolymer Woofer Cone • Butyl Rubber Surround • 3/4" TypeS3 Carbon Injected Polymer Soft Dome Tweeter with Neodymium Magnet

Boston Acoustics S45

4" 2-way S-Series Coaxial Car Speakers

S45 big DISCONTINUED
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Boston Acoustics S45

4" 2-way S-Series Coaxial Car Speakers

4" S-Series 2-Way Car Speakers • 35W RMS • 80W Peak • 4 Ohm • Type S3 3/4" Soft Dome Tweeter • Copolymer Woofer Cone • Butyl Rubber Surround • Neodymium Tweeter Magnet

No Fit Icon Doesn't fit your Sephia

10

4" S-Series 2-Way Car Speakers • 35W RMS • 80W Peak • 4 Ohm • Type S3 3/4" Soft Dome Tweeter • Copolymer Woofer Cone • Butyl Rubber Surround • Neodymium Tweeter Magnet

Boston Acoustics S45 Open Box

(Open Box) 4" S-Series 2-way Car Speakers (S-45)

S45 big DISCONTINUED
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Boston Acoustics S45 Open Box

(Open Box) 4" S-Series 2-way Car Speakers (S-45)

4" S-Series 2-Way Car Speakers • 35W RMS • 80W Peak • 4 Ohm • Type S3 3/4" Soft Dome Tweeter • Copolymer Woofer Cone • Butyl Rubber Surround • Neodymium Tweeter Magnet

No Fit Icon Doesn't fit your Sephia

4" S-Series 2-Way Car Speakers • 35W RMS • 80W Peak • 4 Ohm • Type S3 3/4" Soft Dome Tweeter • Copolymer Woofer Cone • Butyl Rubber Surround • Neodymium Tweeter Magnet

Boston Acoustics ProSeries 6.53 (Pro 6.5<sup>3</sup>) Open Box

ProSeries6.53 6-1/2" + 4" 3-way Component System (PRO6.53)

PRO6.53 big DISCONTINUED
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Boston Acoustics ProSeries 6.53 (Pro 6.5<sup>3</sup>) Open Box

ProSeries6.53 6-1/2" + 4" 3-way Component System (PRO6.53)

6-1/2" ProSeries 3-way Component System • 500W Max • 250W RMS • Copolymer cone woofer • Butyl rubber surround • Rigid die-cast aluminum basket • 4.5" Midrange • 1" Rigid aluminum dome tweeter • Gold-plated terminals

No Fit Icon Doesn't fit your Sephia

6-1/2" ProSeries 3-way Component System • 500W Max • 250W RMS • Copolymer cone woofer • Butyl rubber surround • Rigid die-cast aluminum basket • 4.5" Midrange • 1" Rigid aluminum dome tweeter • Gold-plated terminals

EXCLUSIVE

Boston Acoustics SE45 + Sound Dampening

SE Series 4" 2-way Speakers (SE45) with Two 10" x 10" Pieces of Sound Dampening Material

SE45_CSM big DISCONTINUED
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Boston Acoustics SE45 + Sound Dampening

SE Series 4" 2-way Speakers (SE45) with Two 10" x 10" Pieces of Sound Dampening Material

4" SE Series Speakers • 2-Way Car Speakers • 80W Max • 35W RMS • 4 Ohm Impedance • Copolymer Woofer Cone • Butyl Rubber Surround • 3/4" TypeS3 Carbon Injected Polymer Soft Dome Tweeter with Neodymium Magnet • Included Sound Dampening Material!

No Fit Icon Doesn't fit your Sephia

4" SE Series Speakers • 2-Way Car Speakers • 80W Max • 35W RMS • 4 Ohm Impedance • Copolymer Woofer Cone • Butyl Rubber Surround • 3/4" TypeS3 Carbon Injected Polymer Soft Dome Tweeter with Neodymium Magnet • Included Sound Dampening Material!

 
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