Question about creating my own powered sub using car audio components

[witheringsanity]

Hello!

I recently purchased a ONKYO HT-S3300 receiver and speakers set. The set comes with a passive subwoofer, and I'd prefer a powered sub but can't currently afford one (even a cheap one), so I was thinking about making my own powered subwoofer using some car audio equipment that I have lying around. It will cost me far less than buying a sub and seems like a fun project. I've already seen that you can connect car audio to home systems using a computers power supply. My issue is a very specific problem, my car amp has RCA inputs, while my subwoofer output on the receiver is regular +- speaker wire. I'm wondering if there is any danger of destroying my receiver, amp, or sub if i connect it using a RCA-to-speaker wire converter.

Thanks!

 

[Guest]

Some car audio units are designed to boost the speaker output of a dashboard unit so may be okay with already amplified output from a receiver.

Try connecting an unamplified (line level) signal from the receiver to the car subwoofer and see what level of sound you get.

If it's normal(?) volume the sub is designed to take a line level signal. If very low then the subwoofer is designed to take a speaker level input.

I would not connect an amplified output to a line level input.

 

[soundguruman]

You can't connect speaker wires to a RCA input, it will melt.

 

[Guest]

"You can't connect speaker wires to a RCA input, it will melt."

You'd better tell that to car audio manufacturers.

 

[jacobboe89]

if there is a headphone jack , that may work as the range of a headphone jack is quite close to the range of a pre-amp output , i have seen people use a discman with a cord that has a pair of rca's to test car amplifiers . as for using the speaker level inputs if you have them , remember that an indash unit will be 45-50 watts peak and closer to 8-18 watts rms , the typical speaker output of a av receiver is much higher than that so it isn't likely that speaker level inputs would be suitable for this use . i would try to see if you could make use of the headphone output jack for this purpose , if that don't work , you may have look at passive subwoofer options , some car subwoofers are good for this use , jl w0 comes to mind .

 

[americanaudiophile]

Your receiver contains the amp for the subwoofer since it has its' own speaker terminals. Connecting a different amp may not make any difference but if you want to play with it use a speaker to line level adaptor to connect your homebrew amp to the speaker terminals on the sub.