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RE Audio SRX15D4

300W 15" SRX Series Dual 4 ohm Subwoofer


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Monster Performance

Get big bass with the RE Audio SRX series of car subwoofers.! Easily expect monster performance and deep bass from these quality drivers. The SRX series has twice the power handling and improved audio output over the RE Audio REX series. The striking cosmetics complete the look of the subwoofer, while ensuring that high quality sound is produced. Once mounted, the kraft pulp cone and rubber surround will be visible for all to see. Underneath the cone is a 4-layer copper voice coil, a FEA optimized motor structure, double stacked magnets that all work together to keep the subwoofer linear and sounding great. The RMS of the SRX series is an affordable 300 watts and is perfect for those just starting their car audio system or the long time car audio enthusiast. Like all of the RE Audio subwoofers, they are capable of accepting much more power then the recommended RMS. For excellent performance for a great price, check out the RE Audio SRX car subwoofers

Subwoofer Features:
  • 15" Dual 4 ohm SRX Series Subwoofer
  • Power Handling:
    • RMS: 300 watts
  • Impedance: Dual 4 ohm
  • Kraft pulp woofer cone
  • Rubber surround
  • Pressed steel basket
  • FEA optimized motor structure
  • Linear spiders
  • Foam gasket
  • 4-Layer copper voice coil
  • Double stacked magnets
  • Also available in dual 2 ohm: RE Audio SRX15D2
  • Authorized Internet Dealer
  • 1-year Manufacturer's warranty
SRX 10" T/S Parameters:
  • Electrical Q Value (Qes): 0.45
  • Mechanical Q Value (Qms): 4.87
  • Total Speaker Q Value (Qts): 0.41
  • Free Air Resonance (Fs): 23 Hz
  • Equivalent Compliance (Vas): 203 liters
  • One-Way, Linear Excursion (Xmax): 18 mm
  • Efficiency (SPL 1W/1m): 87.6 dB SPL
  • Effective Piston Area (Sd): 810 cm2
  • DC Resistance (Re): 1.8 ohm
  • Nominal Impedance (Znom): Dual 4 ohm
  • Thermal Power Handling (Pe): 300 W
  • Force Factor (Bl): 14.35

For more information on the Thiele and Small Parameters, visit our T/S Parameters Article

Subwoofer Specifications

Subwoofer Series
Each subwoofer manufactured is part of a series. This is the name of the subwoofer's series.
SRX (RE Audio)
Subwoofer Size
Refers to the diameter of the subwoofer, measured in inches.
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.
300 watts
Voice Coil(s)
Dual voice coil subs have more wiring flexibility than single voice coils subs; however, single voice coil subwoofers provide easier hookup options for wiring multiple subwoofers in parallel or series. You may also run a dual voice coil (DVC) sub in parallel, series, or combination. A quad voice coil has four voice coils and is equal to two dual voice coil subwoofers as far as wiring goes.
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.
4 ohms
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".
87.6 dB
Xmax (millimeters)
Typically measured in millimeters, the Xmax value is the measure of a speaker cone's maximum excursion in one direction while maintaining a linear behavior.
18 mm
Subwoofer Design
This is the design of the subwoofer or the opening of the subwoofer enclosure. Each design has it's own benefits, whether it is a square, circle, or oval.

Round/Circle: This is the typical and common subwoofer design. They have a round cone and are a circle in design.

Square: These woofers are able to achieve a greater cone area in a smaller space. Because of the greater surface area, some square subwoofers will be louder than a round subwoofer of the same size.

Round / Circle
Main Cone Color
This is the color of the speaker's or subwoofer's cone.
Woofer Composition
Lightweight woofer cone materials are essential for efficient operation. Poly cones produce exceptional sound and are sturdy against various changes in temperature. Paper cones are very efficient, and when treated for moisture resistance, will perform at a high level. Poly refers to polypropylene, which is thermoplastic or fibers that are polymers of propylene. IMPP refers to injection molded polypropylene, a commonly used process and material in speakers.
Kraft Pulp
Woofer Surround
A speakers surround is part of the suspension system. The surround protects the cone and prevents it from being displaced as it flexes out from the basket. It is usually made of a durable material like treated foam or rubber in order to withstand the strenuous job of producing bass frequencies.
Magnet Structure
Defines the overall structure of the subwoofers magnet.
Double Stacked
Subwoofer Grille
Most subwoofers are able to accommodate a universal grille; however, some subs include a grille and others have a specific, optional grille available for purchase separately. If "yes", then the subwoofer includes a grille. If "optional (sold separately)" the matching grille will need to be purchased in addition to the sub.
Re-Cone Kit Available
Some higher end subwoofers have replaceable cone assemblies. In case of a blown woofer, a recone kit allows for a simple replacement, as opposed to purchasing an entire new subwoofer.

Recommended Enclosure Specifications

Recommended Enclosure Type
This is the recommended type of enclosure that the subwoofer should be installed into. Some subwoofers are specially designed for particular enclosures.

Sealed: These enclosures completely enclose the air inside the box. These boxes produce a tight bass.

Ported/Vented: These enclosures have a slot of air to escape from the box. The result is a sound that has more "boom".

Bandpass: These are a combination of both sealed and ported enclosures. They can be very efficient, but require tuning for the best response.

Ported / Vented
Minimum Sealed Box Volume
This value indicates the minimum sealed box volume that the manufacturer recommends for the subwoofer. The volume is typically displayed in cubic feet.
1.5 cubic feet
Optimum Sealed Box Volume
This value indicates the ideal sealed box volume that the manufacturer recommends for the subwoofer. The volume is typically displayed in cubic feet.
Maximum Sealed Box Volume
This value indicates the maximum sealed box volume that the manufacturer recommends for the subwoofer. The volume is typically displayed in cubic feet.
2.0 cubic feet
Minimum Ported Box Volume
This value indicates the minimum ported box volume that the manufacturer recommends for the subwoofer. The volume is typically displayed in cubic feet.
2.5 cubic feet
Optimum Ported Box Volume
This value indicates the ideal ported box volume that the manufacturer recommends for the subwoofer. The volume is typically displayed in cubic feet.
Maximum Ported Box Volume
This value indicates the maximum ported box volume that the manufacturer recommends for the subwoofer. The volume is typically displayed in cubic feet.
3.0 cubic feet
Top-Mount Depth
The depth when installed on top of the mounting surface. Measured from the bottom of the speaker's magnet to the bottom of the mounting holes on the rim of the speaker.
Cutout Diameter
The actual diameter of the hole you will need to cut out if you are creating a new mounting location for this speaker, or if you are mounting a subwoofer in a box.
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.


Electromechanical Parameters

Free-Air Resonance (Fs)
The free-air resonance frequency of the subwoofer, measured in Hz. At this frequency the weight of the moving parts is perfectly balanced with the subwoofers suspension system.
23 Hz
Equivalent Compliance (Vas)
This is the amount of air that has the same stiffness as the subwoofers suspension. The greater the rating, the lower the stiffness and larger recommended enclosure. It is measured in Liters.
203 liters
Total Speaker Q Value (Qts)
This is the subwoofers relative damping (Q) at the resonance frequency (Fs), including all dimensionless losses. Essentially, a high Qts value (closer to 1.0) means the subwoofer is great for sealed enclosures and a low Qts value (closer to 0) means the woofer is great in vented enclosures. A Qts of around 0.45 means the woofer will work decently in either enclosure type.
Electrical Q Value (Qes)
The subwoofers relative damping (Q) at the resonance frequency (Fs), including electrical losses. Also called the mechanical damping of the subwoofer. The unitless measurement usually varies from 0.5 10.
Electrical Resistance of Voice Coil (Re)
Amount of DC resistance of the subwoofer when measured with an ohm meter. Typically, this will read less than the impedance rating of the subwoofer.
1.8 ohms
Mechanical Q Value (Qms)
This is the subwoofers relative damping (Q) at the resonance frequency (Fs), including mechanical losses. Also called the mechanical damping of the subwoofer. This unitless measurement usually varies from 0.5 10.
Efficiency Bandwidth Product (EBP)
This number represents the trade off between having an efficient woofer and one with a wide bandwidth. To calculate this number, take the Fs and divide it by the Qes. If the number is below 50, the woofer is designed for a sealed enclosure only. If it's between 50-100 it can be used in either. Lastly, if it's greater than 100 it's designed for vented enclosures.

Specials with this Item

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Warranty and Return Policy

Parts Warranty Duration
1 year
Labor Warranty Duration
1 year
Warranty Provider

Summary of Customer Ratings & Reviews

Rating Distribution

5 Star
4 Star
3 Star
2 Star
1 Star

Average Attribution Rating


snellville GA

SRX 15D2

September 15, 2011

i have 1 of these in a ford ranger on a power acoustiks ovn1 2000d monoblock amp and this thing pounds hard as hell.

3 of 4 found this helpful

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Kansas City, MO

Bedroom subwoofer

December 1, 2012

I bought two of these to replace floppy old woofers in an 80's sanyo 240 watt home stereo. They are crossed over at 3500 hz for now, i'll eventually get proper 80 hz low pass. They really sound fine playing that high though. Down low, im getting pretty flat down to about 30 hz in sealed ~2.5 cubic foot enclosures with a few pounds of cheap poly fill each. With 32 mm total of controlled travel, and since im still well below the 300 watt rms, im sure i could get flat to 20hz with a 31 band eq. As for the speakers themselves, they are flawlessly built. The quality of the malterials exeeds my expectations. The Foam surrounds seem exeptionally tough and are very thick and stiff and seem to dampen the cone nicely. The cone is sort of paper mache that is so stiff that knocking on it with my knuckles sounds like knocking on wood. The only thing i dont like is the big peices on felt glued onto the cone so that the lead wires dont rub and rattle. I just dont like them. Overall, very good subwoofers. Very low tones, very tight, very well made. Sound quality is excellent. I've listened to indie, folk, pink floyd, electronic, punk, rap, and jazz with these and they are really nice. listening to Tom Petty right now. I dont at all use these for what most people think of as car audio. Its important to remember that there are not really any rules concerning whether you use Home, PA, or Car subwoofers. Look at all of them, their T/s parameters, and choose which one is best for your enclosure. I wanted very low frequencies from my undersized enclosures, so i looked for a low Fs, a high xmax, but a low vas. I could have spent twice the money at a different store for undoubtably higher quality speakers, but they would have sounded terrible with my enclosures. Im confident i found some really great subwoofers.

3 of 6 found this helpful

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bozeman, MT


November 20, 2011

I got this sub about 5 months ago and i got it hooked up to a p300 and it is my favorite sub i have bought ever!! I had a 12" type r running 600 rms and this sub is so much cleaner than that one... it takes half the power so no light dimming!! The sub is so clean too but hits super well. Highly recommended sub and amp also must buy!!!

4 of 8 found this helpful

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June 18, 2011

I got this running off a Fosgate p300-1 and it slaps, the sub stays cool as a mofo

4 of 8 found this helpful

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Fallbrook, CA

Great sub that doesn't need tons of power.

June 11, 2011

I have 2 of them running at 300w rms each from my Polk 5ch amp and wow do they hit hard. I used to have 3 12 " Kicker CVRs before running on double the power that these need and they were not as loud as these are. Since they don't need a ton of power more than likely you won't have a light dimming issue since your amp won't be pulling a lot of current. Highly recommended.

2 of 5 found this helpful

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awesome quality

February 19, 2013

I have one of these in a 3.5 cu ft ported enclisure tuned to about 34 hz that I built to re audios recommendation an it is plenty cleaner then my 12w6 that I had on a memphis 1000.1 also built to jls specs. this is perfect on a rockford fosgate p300. sounds better then lots of other subwoofers ive hadd. from american bass kicker infinity hifonics sony jl. nothing can evrn be co.pared to this awesome woofer. an thank you sonic for an awesome product definately would tell anyone to get it with the amp I said above. put it in a ported box an youll be amazed what 300 rms does

3 of 8 found this helpful

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Accessory Tools and Products

Accessories added

NVX 25 ft. of True Spec 12 Gauge Speaker Wire

100% OFC wire with EnvyFlex metallic jacket insulates and protects against damage from extreme conditions.

Your Price $39.99

25 ft. of Streetwires 12 Gauge Speaker Cable

You'll need speaker wire to hook up that new subwoofer!

Your Price $44.95

Belva 23 ft. of 12 Gauge Speaker Wire

Ultra-flexible PVC blended jacket for easy installation.

Your Price $9.99

20 Square Feet of Sound Dampening Material

NVX Sound dampening is thicker than competitors, eliminates rattles and gives you bigger bass!

Your Price $59.99

Dynamat Sound Dampening Trunk Kit

Did you know sound dampening will reduce those annoying rattles and even increase your SPL?

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Stinger Sound Dampening Trunk Kit

Stinger's Roadkill sound dampening series is sure to kill unwanted road noise and rattles! Enough sound dampening for your whole trunk!

Your Price $69.99

12 oz. Can of Adhesive Spray

Spray adhesive used for adhering carpet to subwoofer boxes without bubbles.

Your Price $6.99

40" x 15 Ft Piece of Premium Un-Backed Automotive Trim Carpet

Durable design for long life-span, available in many colors and shades.

Your Price $39.99

Gold Plated Dual Terminal Banana Plug Connector

Enables an expandable, secure connection accepting up to 8 gauge wire.

Your Price $1.99

2" Universal, Professional Heavy Duty Roller for Sound Damping/Dampening

Universal rubber roller to make it easy to install sound dampening.

Your Price $7.99

Car Stereo and Speaker Installation Tool Kit

Includes Test Light, Crimp/Splice Tool, Multi-bit Screwdriver and more.

Your Price $16.99

Xscorpion 9-Piece Nylon Plastic Pry and Chisel Tool Set

Easily removes dash/trims, door clips, panels and pins, rubber grommets and vehicle emblems.

Your Price $14.99

Cordless Multi-Functional Heat Tool Soldering Iron Kit

Continuous working lock allows you to work without holding down trigger.

Your Price $79.99

4 Ft of 1/4" Thick Black Heat Shrink Tubing

Provides abrasion resistance and added protection for your cables.

Your Price $3.99

1mm All Purpose Solder

Solder is all purpose for use on most projects where solder is needed.

Your Price $8.99

15" Protective Waffle Metal Subwoofer Grille

Keep your subwoofer looking amazing while keeping it safe with its durable metal construction!

Your Price $6.99

Scosche SPL Meter

Monitor the noise level of your new car audio system with this SPL meter measuring from 60-135 dB.

Your Price $21.99

1 RE Audio SRX15D4 Subwoofer

Mono Amp

2 Channel Amp - Bridged

2 RE Audio SRX15D4 Subwoofers

Mono Amp

Mono Amp - Option 1

2 Channel Amp

2 Channel Amp - Bridged

4 Channel Amp - Bridged

3 RE Audio SRX15D4 Subwoofers

Mono Amp

4 Channel Amp

4 RE Audio SRX15D4 Subwoofers

Mono Amp

2 Channel Amp

2 Channel Amp - Bridged

4 Channel Amp

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Sonic Electronix Wiring Guide

Wiring Diagram Legend

Warning: The image depicted shows the resistance change when wiring multiple subwoofer terminals. Please refer to your subwoofer's owner's manual for the proper wiring of its terminals. Sonic Electronix, Inc. is not responsible for damage caused to your audio system or vehicle due to improper installation. Please call tech support at 1-877-289-7664 if you require additional assistance.

Product Name: RE Audio SRX15D4

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