Assistance on wiring a sub woofer to a 5.1 sound system (1 Viewer)

[Canuk]

Hello all; I live in south east Asia now and purchased a 5.1 stereo system, it came with five speakers which included 2 large front left and right speaker cabinets, 2 smaller left and right speaker cabinets and one center speaker. The set did not contain a sub woofer, unfortunately by the time I got around to buying a sub woofer for this system all of the major stores here where out of stock. This has been the case here do to extensive flooding, so what I did is I went to a stereo speaker store and purchased a nice sub-woofer, case, speaker cover, wiring and connector plate. I was then referred to a stereo installation company who assembled the unit. When I took it home and tried to connect the unit I was surprised to find that my stereo amplifier uses an RCA out put jack and the new sub has a dual speaker wire connection. This left me with few options so I cut off the end one og my RCA cables and soldered on to the solid core wire the red cable (+) of the speaker wire and peeled back the wire braiding (-) of the speaker wire in an attempt to get the sub-woofer working. Unfortunately that did not work. My question is what should I do now? I suppose the best option is to find a female RCA jack connector for the sub but where and or what is is called is a unknown. Thank you in advance for your advice! ,

 

[gene c]

Two thigs we need to know. Does the subwoofer have an internal amplifier? Does the subwoofer have speaker level (spring clips or banana plugs) inputs and outputs like this one? http://www.parts-express.com/pe/showdetl.cfm?Partnumber=300-631 It would help if you could give us the name and model numbers of the receiver, subwoofer and speakers as not all equipment is designed to work with each other.

 

[Canuk]

Before I start to give specifications to you, let me mention that the sub-woofer is now working by connected it to one of the large size speakers. This is not the final solution though as I want the unit to run on its own channel using the RCA jack output. Regarding the Sub woofer it is a passive device using the stereo Amplifier for power. The speaker itself is called a Mark Pro Model MP-1092D, it is a 10” Double Magnet speaker 40oz. x 2 (consisting of 40oz. Magnet and 1.5” Dual voice coil). It has double voice coils with 1000 W maximum capability. Other info is: RMS 200 Watt Impedance 4 OHMS Sensitivity 90dB 1W per 1M Frequency Response 50Hz – 700Hz The stereo system is called a Fantasia FHT-9002 System (a 5.1 system) As this is a stereo system is sold here in South East Asia you will not find much on it. The specifications are as follows: Output: Main Channel (12khHz/4ohm Stereo, RMS) 80W+80W Center Channel (4 ohms, RMS) Surround Channel (4 ohms, RMS) Cross Attenuation >43dB Total Harmonic Distortion

 

[gene c]

"This is not the final solution though as I want the unit to run on its own channel using the RCA jack output." If you want to connect a passive subwoofer to the RCA subwoofer output of the receiver then you will need a seperate amp to power it. The receivers subwoofer output is a low-level signal which needs to be amplified before connecting it to the subwoofers driver. There are dedicated subwoofer amps you could buy or you could use any old receiver you may have laying around by connecting the original receivers subwoofer output to this other receivers CD input (L or R) and connecting speaker output (L or R) to your subwoofer. Make sence? But you need some kind of amp between the receivers subwoofer output and the subwoofer itself.

 

[Canuk]

Yes I understand, I had thought that amplifier on my stereo system would be enough to power the sub-woofer speaker directly, based on your comments this however is not the case. In your mind what would be smallest amplifier that I would need to power the speaker in a Home Theater arrangement. One question for you, why is it that my HTPC amplifier is able to power the sub-woofer when connected to one of the side speakers and does no have the power to amplify the signal through the RCA jack? As mentioned above: 4 Effective Frequency Range under Limited Gains: Main Channel 10Hz – 20kHz (+1/-2Db) Center Channels 10Hz – 20kHz (+1/-2Db) Surround Channel 10Hz – 20kHz (+1/-2Db) SW Line Out Put 10Hz – 20kHz (+1/-2Db) Thank you again.

 

[Al.Anderson]

One question for you, why is it that my HTPC amplifier is able to power the sub-woofer when connected to one of the side speakers and does no have the power to amplify the signal through the RCA jack?

Your receiver (and most modern receivers) has an amplifier attached to all of the speaker outputs *except* the sub channel. It takes more power to drive the lower frequencies, so modern systems offload that to a dedicated amp, usually placed inside the sub enclosure. If you were to attach amyof the other receiver outputs to the sub you'd find that it would work just fine. (Of course it wouldn't be receiving the correct "sub" signals, but it would work.) You can get a "mono-block" amp and run the sub. A the case with most of this equipment you can spend from $50 - $5000. Since it's a 4 ohm speaker, you'll need to spend a bit more for an amp that can drive it. I think the people who agreed to build you a "sub" should have asked more question before they did the work. Of course, I'm not sure what information you gave them; or how things operate in SE Asia.

 

[Canuk]

Thank you Mr. Anderson; Excellent reply to my questions, thank you again!