I Need Help!

[Crow47]

Some of you may remember a week ago or so I posted a thread about wanting to replace a Logitech subwoofer. I ordered a replacement woofer and it arrived today. I can't get it to work! Sound comes from the satellites, but there isn't a peep out of the woofer. I bought a MB Quart RWE-204. Here's the link http://www.woofersetc.com/index.cfm?fuseac...Product_ID=3775

 

I have some pictures here to help:

 

This is a picture of the wires going into the subwoofer itself.

 

This is a picture of what the manual tells me to do, I have it wired in a series to get 8 ohms.

 

This is my wire joining job here, thought I'd include this. Something wrong with that perhaps?

 

As always, thanks for the help!

Edited February 12, 2009 by Crow47

[BionicSniper]

Do you have another amplifier you can test it with?

 

Also you can wire it to 4 Ohm and you will get more power out of it. That may be the problem. The plate amp in that logitech box may not have the umph to move that woofer.

[Fanatic]

you have a 4ohm sub running at 8ohms? I think your wiring is incorrect. It would seem to me that you want 4 ohms. The sub is also dual voice coil and the instructions you show really don't show the wiring config enough. The other thing I noticed is the sub is 150watts RMS. Last time I bought computer speakers I was lucky to get 100RMS without dropping serious coin.

[Waco]

Unhook it from the amp and use a 9v battery to make sure the woofer itself is okay. You look like you have it wired properly.

 

 

you have a 4ohm sub running at 8ohms? I think your wiring is incorrect. It would seem to me that you want 4 ohms. The sub is also dual voice coil and the instructions you show really don't show the wiring config enough. The other thing I noticed is the sub is 150watts RMS. Last time I bought computer speakers I was lucky to get 100RMS without dropping serious coin.

You can't wire a DVC 4 ohm sub to 4 ohms...

[Fanatic]

Unhook it from the amp and use a 9v battery to make sure the woofer itself is okay. You look like you have it wired properly.

 

 

 

You can't wire a DVC 4 ohm sub to 4 ohms...

 

Not what the link says:

 

"All woofers from 8" to 15" are available in 2 ohm dual voice coil and 4 ohm dual voice coil configurations to ensure compatibility with any amplifier".

 

* Peak Power Handling: 300 Watts

* RMS Power Handling: 150 Watts

* Frequency Response 28 - 300

* Subwoofer Size: 8"

* Impedance 4 ohm

* Dual Voice Coils

* Recommended box 1 (Vb) 0.50 cu ft. sealed

* Sensitivity 2,8dB

 

What am I missing?

Edited February 19, 2009 by Fanatic

[Waco]

What am I missing?

There are DUAL 4 ohm voice coils. He can either wire it in parallel (2 ohms) or series (8 ohms). The only way he could get a 4 ohm load is to buy two of them and wire them in series-parallel, but that's not what he wants to do anyway. His stock amplifier is meant to handle an 8 ohm load.

[Verran]

There are DUAL 4 ohm voice coils. He can either wire it in parallel (2 ohms) or series (4 ohms). The only way he could get a 4 ohm load is to buy two of them and wire them in series-parallel, but that's not what he wants to do anyway. His stock amplifier is meant to handle an 8 ohm load.

Is that a typo? Series should be 8 ohms, shouldn't it? Also I would think wiring the separate voice coils in series would require a jumper wire between the two currently unused terminals, wouldn't it?

[hardnrg]

There is a jumper of sorts connected for series (in the photo, and the diagram), and two short jumpers for parallel... this is how the diagram reads

 

Are you sure it's the subwoofer driver that was faulty, and not the sub amp? Like have you tried the old (and new) sub on a regular amp? Or the satellite output connected to the sub driver should give you *something*, even with a filtered frequency range

 

On the impedance, you should have got the MB Quart RWE 202, which has dual 2 ohm coils (so you can run the coils in series for 4 ohms from a mono amp that was designed for 4 ohm impedance)

 

Have you tried connecting the sub amp wires to terminals 1 and 3, or 2 and 4? This should give you 4 ohms according to the manual (diagram 2 on that page)... the "standard" wiring appears to be showing a dual channel (e.g. stereo) amp feeding each coil separately, without jumpers.

 

According to diagram 2, the terminals are: Coil1+, Coil2+, Coil1-, Coil2-... so the jumper configurations shown are correct...

 

Yeah, I'd try individual coils (1/3, 2/4) and also try a different amp

[Waco]

Is that a typo? Series should be 8 ohms, shouldn't it? Also I would think wiring the separate voice coils in series would require a jumper wire between the two currently unused terminals, wouldn't it?

Sorry, yes. 8 ohms for series. There is a jumper in the photo, it's just hard to see.

 

On the impedance, you should have got the MB Quart RWE 202, which has dual 2 ohm coils (so you can run the coils in series for 4 ohms from a mono amp that was designed for 4 ohm impedance)

He said before that the stock impedance was 6 or 8 Ohms. It's safer to go with a slightly higher impedance than to drop below what an amp is rated for.

 

He really just needs to get a 9v battery to test whether or not the sub is working properly.