Bavsound Ghost Underseat Subwoofer Set - 8 Ohm for S677A/S688A Top Hi-Fi & Harman Kardon
More bass without clarity is just noise. Bavsound's Ghost Underseat Subwoofers are engineered to be a plug and play replacement for your existing subwoofers, providing you with louder, cleaner and clearer bass.
WHAT'S INCLUDED? ABSOLUTELY EVERYTHING YOU NEED FOR INCREDIBLE SOUND
Driver & Passenger Side
(2x) Bavsound Ghost Underseat Subwoofer, 8 Ohm
HOW TO DETERMINE WHICH AUDIO SYSTEM YOUR VEHICLE IS EQUIPPED WITH
BASE STEREO SOUND SYSTEM¹
The base level stereo sound is standard on pretty much all Australian delivered models. Specifics vary by vehicle, but this audio system is generally characterized by a lack of an external amplifier, and usually just 6 total speakers (often without tweeters), and generally very poor overall performance. There is no option code for the base stereo system.
HI-FI SOUND SYSTEM - S676A
Hi-Fi Speaker System comes as standard on only a few Australian delivered models. Although exact specifics vary from vehicle to vehicle, this audio system is generally characterized by 10 total speakers and an external amplifier, no user adjustable "DSP" processing or equalizer settings, and "average" overall performance. The option code for this system in a VIN search is S676A.
HARMAN KARDON SOUND SYSTEM - S674A/S688A
If you have "HK" or Harman Kardon labels in your interior, you have this audio system. If you do not have those labels, then you do not have this audio system. The option code for this system in a VIN search is S688A. On some models such as the 1 and 2 Series, option code S674A 'Hi-Fi System Harman Kardon' may be installed. This system is very simlair to the normal Hi-Fi sytem but comes with more speakers and is not as powerful as the premium Harman Kardon system.
TOP HI-FI / LOGIC7 / PROFESSIONAL DSP - S677A¹
This is BMW's "premium" audio system referred to internally by BMW as "Top Hi-Fi" or "Hi-Fi System Professional DSP." There are a number of different names under which this system may be marketed depending on the year and model of your BMW including Logic7, Premium "DSP" and Professional DSP. If your vehicle is equipped with one of these audio system types listed above or referred to by your dealer or invoice as having option code S677A. If you have an "M" vehicle (M3, M5, etc.) you may have DIRAC or Enhanced Premium Sound (EPS). Please view the descriptions of those audio systems to determine whether you have DIRAC or EPS, or check with your dealer.
DIRAC SOUND SYSTEM - S752A²
Available only on "M" model BMWs such as the M3, M5, M6, and so on, this was BMW's "ultimate" audio system, positioned above the Premium audio system offerings. This offering was later replaced by BMW's "Enhanced Premium Sound" system. Changes from the Top Hi-Fi Premium (S677A) system are different speakers, a more powerful amplifier, additional DSP processing, and better hardware crossovers. DIRAC can be identified by silver trim rings on interior door speaker covers and a silvery metallic speaker cone visible through the front speaker covers.
ENHANCED PREMIUM SOUND - S752A²
Available only on "M" model BMWs such as the M3, M5, M6, and so on, this is BMW's "ultimate" audio system, positioned above the Premium audio system offerings. This offering replaced the earlier "DIRAC" system. If you do not have an "M" car, you do not have this audio system. Changes from the "normal" Premium (e.g. Logic7, Harman Kardon, etc.) system are different speakers, a more powerful amplifier, additional DSP processing, and better hardware crossovers. Enhanced Premium Sound is difficult to identify physically as it has the same number of speakers and locations as the "normal" Premium audio systems.
If you aren't sure about what system your BMW is fitted with just send your VIN number through to us and we will be more than happy to assist you. Your VIN will also be required to place an order so that we can make sure you have the suitable kit for your BMW.
¹ Some models such as the E60/E61 5 Series with S677A Top Hi-Fi use a 4 Ohm underseat subwoofer instead of a 8 Ohm. Please contact us if you need to confirm which subwoofer set is suitable for your model before ordering.
² Bavsound Underseat Subwoofers are NOT COMPATIBLE with S752A audio systems.
DOUBLE THE BASS IN YOUR BMW, IN ABOUT AN HOUR
HOW DO BAVSOUND DELIVER BASS THAT'S LOUDER, CLEANER, AND TIGHTER WITHOUT CHANGING THE FACTORY AMP?
In a word, efficiency. Every watt of power generated by your amplifier yields about 2x the bass output with Bavsound's woofers vs factory woofers.
If you're not familiar with the concept of "efficiency" in audio, just use this analogy: with your factory woofers, your amplifier is like a 200hp motor in a 4,000lb Camry.
With Bavsound, it’s like the same 200hp motor in a 2,000lb Lotus Elise - twice the performance with the same power.
YOU WON'T JUST LISTEN TO YOUR MUSIC, YOU'LL FEEL IT
This frequency response graph shows the significantly higher, more balanced output of Bavsound's subs (yellow) vs. factory Harman Kardon subs (white). Higher and "flatter" is better.
2X the bass - Bavsound's woofers are 10 dB+ louder from 20Hz to 60Hz vs factory woofers, resulting in twice the loudness in this critical “sub-bass” range (and over 8x the sonic energy). You won’t just hear the bass; you’ll feel it.
Nearly flat frequency response for exceptional linearity in the key sub / mid-bass frequency range from 40Hz to 200Hz (+ or - 3 dB). Which means "clean" and balanced bass.
100% PLUG & PLAY
Installs and fits just like your factory BMW woofers, right down to the bolts and factory style plug. (NOTE: 2018+ X3 models and vehicles with “Base” audio systems require slight modification to factory enclosure and may necessitate additional tools).
SIMPLE, DO-IT-YOURSELF INSTALLATION
Takes less than 90 minutes and only basic tools, even for a total novice. No complex wiring or additional hardware or installation is required. Simply unbolt your front seats, remove the woofer covers, unbolt your factory woofers, and install the Bavsound subwoofers. That's it!
USE YOUR FACTORY AMPLIFIER AND GET EXCEPTIONAL BASS RESPONSE (OR THE REVENANT AMPLIFIER, AND GET EVEN MORE)
Bavsound utilize your factory amplifier to generate amazing bass response in your BMW. To do so, they've designed their woofers using technologies like oversized neodymium magnets and lightweight poly cone to maximize every watt of power they generate and translate that into raw output. That means amazing bass response without replacing your amplifier.
Want even more bass? Ask us about the Bavsound Revenant Amplifier.
SUPER TIGHT, PUNCHY MIDBASS
Your factory underseat woofers aren't just subwoofers; they're midbass drivers. That means they play not just the lowest frequencies, but also "punchy" midbass frequencies like snare drums and high bass guitar notes.
Unlike Bavsound's woofers, which are designed to outperform the factory woofers for both subwoofer and midbass frequencies, other underseat subwoofer upgrades on the market are only capable of playing sub frequencies, not midbass, so you miss a huge portion of the frequency range.
FACTORY MATCHED IMPEDANCE
Depending on your audio system, your factory BMW woofers come in 2, 4, or 8 Ohm impedance. The Bavsound woofers are matched to the impedance of your factory woofers (Bavsound have different versions for each) to maximize performance and ensure the longevity of your factory amplifier.
UPGRADEABLE DESIGN WITH 160W RMS / 320W PEAK POWER HANDLING PER WOOFER
Even though Bavsound's woofers are designed to be extremely efficient to maximize the output of your factory amplifier, they're also built for upgradability. You can power them with an aftermarket amplifier of your choice, up to 160W per channel, but we recommend the ultimate amplifier upgrade for your BMW: The Revenant, by Bavsound.
Translation? If you'd like to melt your face off with absurd quantities of bass, you can - just add an amp.
BAVSOUND'S PRODUCTS ARE BULLETPROOF, SO IS THEIR WARRANTY
Everything Bavsound sell has been engineered for durability and longevity, and they know what they sell will last. And last. And last.
That’s why all Bavsound speaker upgrades and subwoofer systems are backed by an industry leading 4 year limited warranty.
So if something breaks, send it back. We'll replace it at no charge.
THE PERFECT MATCH TO BAVSOUND'S LEGENDARY SPEAKER AND AMPLIFIER UPGRADES
Amazing bass response can transform your listening experience, but if you want the absolute best, overall sound quality and clarity matters too.
That's why Bavsound engineered the Ghost Underseat Subwoofer Upgrade System to perfectly and seamless match the legendary Stage One Speaker Upgrade Kit and Revenant Amplifier Upgrade.
INSTALLATION GUIDES
Note: Professional installation is recommended on some later models (such as the G05/G06 X5/X6, G2x 3 & 4 Series, some models with Base Stereo) that have the standard subwoofers glued into the housings. Please contact us if you have any questions about the installation of the subwoofer kit to suit your model.
FREQUENTLY ASKED QUESTIONS
Can I purchase just the subwoofer enclosure? I already have an amplifier and subwoofer.
Unfortunately, no. Bavsound's Ghost Subwoofer Systems are designed to work together as a unit, with each component perfectly matched to the rest of the system and optimized for your exact BMW. Bavsound also manufacture and warehouse the kits as complete units, so the individual components simply aren't available for sale outside of the entire kit!
Will the Ghost Underseat Subwoofers make a big impact in bass response in my BMW?
The Bavsound Ghost Underseat Subwoofers are the perfect upgrade to dramatically improve bass response in your BMW. The subs pick up right where our midranges roll off, covering the full mid-bass to sub-bass spectrum. This gives your fuller, richer music, and eliminates any gap in your music between the midrange and sub-bass.
The subs give you much tighter, louder, punchier bass, and drastically transform your music. They are engineered for efficiency, and maximize every watt of power generated by your amplifier to yield far more bass output than your factory subwoofers.
Can I install the Ghost Subwoofer System myself?
If you can put together IKEA furniture, you can install the Bavsound Ghost Underseat Subwoofers in your BMW.
Models
1 Series / E82 / E88 (2007-2013) / 1 Series M (1M)
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