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We have resisted this because we know how many audiophiles feel when it comes to the association of mobile audio and the high-end. After the request from several of our dealers who got requests from their customers asking if it could be done and some placing orders to do so, we decided to add some information associating the use of the Magellan anti-subwoofers and obtaining sound quality from your almost good mobile system. We hope that this helps all of those that are inquisitive about this subject and this may become a new profit center for creative high-end dealers.

All vehicles do not qualify for audiophile quality bass. It is accepted that certain amounts of low frequency noise is unavoidable and in some cases a distinguished note of the tail pipe maybe more desirable. Vehicles that have an intentional high level of ambient noise may be better off with plain old resonant bass that is loud enough to be heard over the vehicle ambient platform. This type of mobile installation is not the intended application for TBI musical subwoofers as it is not possible to produce a natural musical event in the presence of such high levels of random noise.

Your vehicle is your home away from home. We will sit in traffic, travel long distances and generally spend so much of our time in our vehicles. If we are an audiophile we dream of being able to spend all of that time enjoying our favorite tunes in the manner that we are accustomed.

The disparities that exist when an auto sound system is upgraded are incredible and one begins to wonder just what can be done to really enhance the sound of your system. All that aftermarket installers seem to be able to add is volume and boom.

Audiophiles are generally mature individuals who listen in a sophisticated way. If we play it loud then it is a natural loud with a balanced sound that was obtained through time, expense and listening experience. How do we transport those wonderful achievements into our second home?


Most audiophiles have a decent vehicle with a decent sound system. Whether it is a factory unit which by today's standards can be quite adequate or a tweaked system the last hurdle is getting the right bass in the system. The automobile has by no means the quiet background of our main listening area and in particular has extreme low frequency noise below 40 Hz and this is with the windows closed. The dominant frequencies will be in the subsonic region but can be over 100db at 30 Hz. This is an endemic problem associated with the engine, chassis and dimensions of even the most quiet cars. It is for this reason that the conventional subwoofer is even less effective in a vehicle than in a high quality home audio system.

This problem is the Achilles heel for the auto sound system and the major deterrent into most proceeding further with major investments into a mobile sound system. We have all heard the thunderous noise associated with typical auto subwoofers sometimes even when we are in a different car. Why so loud?

We just mentioned the fact that the automobile is a low frequency noise generator sometimes producing levels greater than 100db in the sub 40Hz region. The better quality autos will bring down the absolute noise levels but it isn't consistent as we drive, changing for road conditions and other uncontrollable factors. The sound generated by a typical subwoofer, as most audiophiles know it, is a noise component of its own sounding separate from the main system. This condition is multiplied many times when the conventional subwoofer has to compete with road noise to be recognized. The result is an impossible condition with one noise source competing to dominate another noise source while not providing you with bass extension for your almost perfect sound system. Another major problem is that the subwoofer is producing the same range of sound as the main speakers (at crossover) with a completely different resonance characteristic. There will never be a point of integration because there is a great difference in settling time for the cones. Sound quality is the main goal for an audiophile and that doesn't change because we are going mobile.


The TBI passive subwoofer modules are right at home doing what they do right in your vehicle. The MAGELLAN VI su occupies only .66 cu ft in your auto trunk while the MAGELLAN VIII su occupies only 1.2 low profile cu ft. These low profile subs will exist in your trunk or the bed of your SUV, or behind the rear seat of your pickup without notice except for the unbelievable sound that you will hear from your vehicles speakers. The Embedded Transmission Line located within the enclosure assures consistent accurate performance regardless of the contents of your trunk or vehicle. Your speakers will sound clearer because of the acoustic damping produced by the high-pressure wave of the TBI Magellan. You will think that you just bought the best speakers at the same time. The sound will be full, rich and deep without blasting and the seamless connection that our bass extension modules have with your main speakers produces music that doesn't have to compete with the low frequency road noise to be enjoyed. You can actually play your music at a volume lower than the road noise and not miss one deep rhythmic beat. The best thing of all is the way that the sub attaches itself to all of your speakers in a seamless integration providing perfect bass extension without giving a clue as to it presence in your system.


The installation of a TBI sub is no different than installing a conventional subwoofer. It is of 8 ohm impedance so for most car amplifiers you will use the bridge connection to achieve maximum output. All that is required is a proper subwoofer amplifier with an adjustable low pass filter. It will probably be best installed by your local reliable and knowledgeable auto sound installer but if you are handy it is a cinch and you may already know how. We recommend the Phoenix Gold Octane-R2.2 Power Amplifier (75W RMS into one or two subs when bridged) or the Octane-R2.2 Power Amplifier (125W RMS into one or two subs when bridged) or similar as they have a built in crossover range of 30Hz to 300 Hz and an adjustable subsonic filter from 20 Hz to 55 Hz. These amplifiers are extremely musical and stable with a low profile for many mounting options. Some of the Key musical bass features of these or other amps that you might discover are:

  • 18 dB Low pass continuously variable crossover (30-300 Hz)
  • Monoblock amplifiers load stability = 2 ohms (multiple subs)
  • 18 dB Subsonic filter (20-55 Hz)
  • Class A/B output stage and some more recent digitals
  • Floating Speaker Level and Line Level inputs with volume control

The passive MAGELLAN subs can be secured in the trunk or interior bed of a SUV using anchor points and flanking the sub with bungee cords to secure into position. This makes removal very simple when banana plugs are used for connecting allowing dual purpose home and auto use. They can be vertically mounted in pickup trucks using this same method and in some cases especially for truck based vehicles mounted under seats or in a vertical position. When installed in this manner the sub may easily be transferred from car to home and back without making adjustments since your home subwoofer amp and car subwoofer amp would not have their controls changed and therefore the system would be already adjusted when connected. You only need to place it back in the same physical location each time.

In some luxury automobiles there is a metal partition between the trunk and the passenger compartment that will prevent transfer of the sound from the trunk. This is easily remedied by your installer by mounting the subwoofer with port towards the metal panel. A small hole slightly larger than the size of the port located at the proper position in the panel (when the woofer is anchored) will allow transfer of sound into the passenger compartment. It is best to locate the woofer as close to the metal panel as possible and seal the opening with a semi-solid foam or solid type circular seal (see diagram). If solid then it should be oversized to prevent altering the tuning of the Magellan sub. If at all possible close mounting with only a gasket type seal would input all of the bass sound into the vehicle and minimal into the trunk. This is desirable in expensive vehicles when care has already been taken to minimize sound spill over into the trunk area with the factory sound system. When making this type of installation care must be taken to avoid any obstacles located behind the panel especially in some cases the fuel tank.

Please use these design templates MAG VI su or MAG VIII su for permanent trunk or bed mounting using the threaded inserts supplied on the subwoofer for the spikes and feet. The bolts supplied for the feet in conjunction with 4 x 1/4 x 1" fender washers will provide suitable fastening means. Shorter bolts .5 in to .75 in should be used if the feet are not used to prevent puncturing of air seal. The indicated dimensions will allow for both vertical or horizontal installation using flat metal strips or a metal plate attached using bolts with the inserts. These are printable PDF documents that you may use to help with your auto-suv-boat-bus -motor home installation. Valuable text information and a basic vehicular speaker layout diagram are also available in PDF form and can be downloaded and printed for your assistance. Vehicle specific Magellan VI su brochure.

Please call or e-mail for more specific information. 1-877-828-7829 or


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