Audio Systems/car audio


okay guess i should just go with my question and not waste your time i have 2 10 inch rockford fosgate r2d2 dvc 2 ohms subwoofers to go in my 08 volkswagen gti. im so lost about subs, tried reading about it but my brain turned to mush.what would be a good amp for these? im not putting them in myself just want to get everything ready so the audio place doesnt rip me off. so hopefully you can help if not thanks for reading this. any other questions you need an answer to feel free to ask me

Subwoofers are for producing low frequency audio.  Usually considered to be below 100Hz down to 30Hz or lower.  There should be a gentle crossover from the sub to the main speakers.  Audio at low frequencies is fundamentally non-directional so often one subwoofer is all that is needed in a multi-speaker reproduction system.

Subwoofers are usually either self powered (meaning power amplifier is built into the sub box) or speaker in the box only (which requires external sub amplifier to power).

The head unit should have a sub output which can input to the power amplifier of either type. If no sub output one must be constructed by the user either with a separate crossover network or a home built DIY crossover.

Car audio amplifiers are plentiful and cheap, relatively speaking, compared to some other components of a car system.  You can look through reviews found online, talk with sales people at the audio shops, discuss with friends, read the mags, etc. for information about specific models, brand names and testing reports.

Since you are using dual voice coil speakers you must decide the amp by how you are going to wire up the speakers. If you are running a 2 ohm speaker unit you must select an amp that will handle that low impedance.  Or, you can put the coils in series for a higher impedance if your amplifier likes to see 4 ohms or 8 ohms.  Most amps now days are good for at least 4 ohm loads. If the amp is a switching type it will almost always be rated for 2 ohm loads or even as low as 1 ohm.

As to a model for your system you should keep on narrowing it down as you decide on the system finalization.  I do not make equipment recommendations because there are too many subjective factors involved in the selection process.  Subjective factors are such things as power output, impedance matching, physical configuration for mounting, color, weight, heat ventilation requirements, space needed in the vehicle and so forth.  Actually, unless you are going for a show car or something at the esoteric level the sub amp is about the easiest component to select.  Maybe price is the key driving parameter - if you are on a budget.  Amplifier sound quality is generally an order of magnitude superior to the loudspeakers so far as reproduction fidelity is concerned.

Carry On.  Good Luck.  

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Audio Design Engineer; systems, loudspeakers, cd/dvd players, etc. I am knowledgeable in all high end audio equipment and installations. MAKE SURE YOU GIVE A MAKE AND MODEL NUMBER AND CAR IF IT IS AN AUTO QUESTION. Note: I am getting some who ask good questions that take a lot of time to research but then the questioner fails to read the answer. Please don't ask questions unless you are seriously looking for an answer. If you find an answer to your question otherwise then let me know with your reply. Thank you.


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