5.1 Subwoofer and Center mixing

[nin-ha]

Hey guys, I just got a dedicated subwoofer today (by dedicated I mean one meant to go into a receiver for a home theater) and I'm trying to set it up as part of my 5.1 set up for my computer. My set up is actually kind of ghetto in a sense. I have two, two piece speakers that are probably meant to be 2.0 set ups separately, all hooked up to my computer and ran as a 5.1 set up. Till today I was just missing a subwoofer and I saw a deal at Best Buy for an Insignia NS-RSW211 for $25 and decided to get one thinking that it'd be a piece of cake set up. Well after an hour of installing and uninstalling drivers I'm still at square one with my set up. The problem is that on my motherboard, the Center and Subwoofer channels are combined into one even though I have six channels on the board. I linked some pictures of my set up in the Realtek client. When I have the "Swap Center" feature on, I have no center but the bass plays out of the sub. However when I have "Swap Center" off, the bass plays out of the center and nothing comes out of the sub. I've been surfing a lot of different forums and no one really has a good solution besides buying a dedicated sound card.

http://imageshack.us/f/811/swapcenteron.jpg/

http://imageshack.us/f/402/swapcenteroff.jpg/

 

[Pinhedd]

Almost all audio DACs (onboard and discrete) use 3.5mm jacks to pair channels. Front left with front right, side left with side right, rear left with rear right and center with sub.

How are you separating the 3.5mm jack into discrete center and sub wires?

 

[Pinhedd]

okay after inspecting your setup a little more (keep in mind I still don't know anything about your wiring) I see two problems.

In the first photo you have swap center enabled and both center/sub speakers enabled. In the second photo you have swap center off but Subwoofer disabled. Set this to both enabled (if you have a center speaker, you don't mention this anywhere) and leave swap center off because I almost guarantee that you don't need it.

Second, in both photos you have full range speakers enabled. Unless you paid several hundred bucks for those speakers and they happen to weigh 30 pounds they are almost certainly not full range speakers. Full range speakers can reproduce all frequency components from 10hz through 20,000 hz. Most speakers can only reproduce components from 100hz through 20,000hz. The subwoofer is supposed to handle components from 10hz-100hz. Effectively, full range speakers can make a subwoofer unnecessary. Sending 10-100hz components to non-full range speakers will simply result in extreme attenuation and possibly a little static.

To make matters worse, having both full range speakers AND a subwoofer will confuse the *** out of Windows. It doesn't know whether to separate out the low frequency components and send them to the subwoofer or mix them into the other speaker channels. The system doesn't know that your speakers aren't capable of reproducing the full range of sounds. What this translates into is audio streams that have a LFE channel (Low-Frequency Effect, aka the .1 in 5.1 and 7.1) will have it sent to the subwoofer as it should be but low frequency components will not be stripped from the other channels, effectively neutering the bass components of these channels completely. The correct thing to do is disable full range and let the audio codec move the components to where they belong.

Unfortunately most Realtek audio codecs do a piss poor job of resampling and remixing this audio. This tends to introduce a lot of noise into all of the channels that wouldn't be there on a discrete Asus or Creative Labs card.

 

[nin-ha]

I know jack **** about audio software and crap. I'm just a gamer who knows how to put together a computer. I do not have a dedicated center speaker. Well I do but I don't use it b/c it's ac-adapter makes a really obnoxious high pitch squeal. I'll try what you suggested tomorrow. I already packed up the sub in means of returning it b/c it wasn't worth all the effort. When I did get it to work it was also extremely quiet as if it were being played out of my iPhone or something. Any ideas on that? Or is it just the faulty set up that's causing it to play so quietly?

EDIT: so here's a quick clarification. When looking at the speaker, the FRONT left and right is one set of Altec Lansing desktop speakers that are connected to my computer by a 3.5mm stereo jack. The REAR left and right is a pair of Logitech portable speakers that are connected the same way to my computer; one 3.5mm jack. In total at the moment since I ripped out the sub b/c I was thinking about returning it, I only have 2 wires connecting to the back of my computer. The CENTER is being played by BOTH the front speakers.

 

[Pinhedd]

You shouldn't have a center channel if you don't have a center speaker. Disable that in the audio configuration and let your decoding software take care of it

 

[nin-ha]

Alright so I plugged in my sub again and I turned OFF swap center and enabled both Center and Subwoofer. THat's the only way my sub will be detected and will only work if I test it through center. I can't make my sub run without enabling center as well. I'm going to assume that it's b/c they're in the same channel. So right now the only way that I'm getting the sub to work is that I have to enable BOTH center and sub, and with swap center OFF, it plays through center. With swap center ON it plays through the subwoofer.

 

[Pinhedd]

Each 3.5 mm jack has 3 wires. One for each channel and a common reference. They're not the same channel, just the same cable. If the sub was not designed to work with a center speaker it may have had its jack constructed such that the signal sent to the subwoofer is normally the one that would be sent to the center, thus requiring the swap center option

 

[nin-ha]

I bought a phono to 3.5mm mono cable in order to connect my sub to my computer. Could that be the problem?

 

[Pinhedd]

I bought a phono to 3.5mm mono cable in order to connect my sub to my computer. Could that be the problem?

Yes absolutely, it's just connecting the channel the wrong side. This isn't an issue so long as you have the swap center/sub selected

 

[nin-ha]

Alright so you're saying the solution to my problem is that I just need to have swap center on and then I'm solid? what about the volume issue though? The thing is so quiet it's barely noticeable unless you're actually listening for it. Is that something wrong with the sub or is it just b/c it's connected to my computer rather than a receiver? Is there anything I can do to boost the sub? And should I have the sub playing from the sub on Realtek, or the sub playing from the center?

 

[Pinhedd]

Alright so you're saying the solution to my problem is that I just need to have swap center on and then I'm solid? what about the volume issue though? The thing is so quiet it's barely noticeable unless you're actually listening for it. Is that something wrong with the sub or is it just b/c it's connected to my computer rather than a receiver? Is there anything I can do to boost the sub? And should I have the sub playing from the sub on Realtek, or the sub playing from the center?

You will have to enable the +15db bass boost. This is turned off by default so you don't damage a subwoofer accidentally by having it both pre-amped and post-amped. You can find the setting around there somewhere, otherwise look for a volume control on the subwoofer itself

 

[nin-ha]

I found a way to boost in Room Correction but that only allowed me to boost it by 10db. It's still fairly quiet. Is there an equalizer I can download that will allow me to boost the volume of the bass/center?

 

[Pinhedd]

I found a way to boost in Room Correction but that only allowed me to boost it by 10db. It's still fairly quiet. Is there an equalizer I can download that will allow me to boost the volume of the bass/center?

Doubtful. Does the subwoofer not have its own volume control or amplifier? If it's a pre-amp subwoofer you shouldn't be using it with an onboard audio codec

 

[nin-ha]

It has its own volume knob but even with it turned up all the way it's not that impressive. I have no idea if it's a pre-amp sub. All I know is that it's meant to go into a receiver b/c it's a home theater sub not a computer one. Anyway of finding out? It's an Insignia NS-RSW211.

 

[Pinhedd]

Yes that has its own built in amplifier. Did you turn the full range speaker settings off like I said earlier?

 

[nin-ha]

Yeah I turned off full range speakers. Here's a picture of the final set up. Nothing plays out of center so I crossed it out. My sub plays out my sub though which is good. So there's nothing I can do about the volume?

http://img841.imageshack.us/img841/7413/speakersfinal.jpg

 

[Pinhedd]

It might just be that the sub you bought wasn't designed for use with a PC but only with an external amplifier, that's my guess

 

[nin-ha]

Most likely. It was meant to be part of a home theater set up by being plugged into a receiver. Well you were very helpful. Thank you.

 

[nin-ha]

Best answer selected by nin-ha.

 

[Anazro]

okay after inspecting your setup a little more (keep in mind I still don't know anything about your wiring) I see two problems.

In the first photo you have swap center enabled and both center/sub speakers enabled. In the second photo you have swap center off but Subwoofer disabled. Set this to both enabled (if you have a center speaker, you don't mention this anywhere) and leave swap center off because I almost guarantee that you don't need it.

Second, in both photos you have full range speakers enabled. Unless you paid several hundred bucks for those speakers and they happen to weigh 30 pounds they are almost certainly not full range speakers. Full range speakers can reproduce all frequency components from 10hz through 20,000 hz. Most speakers can only reproduce components from 100hz through 20,000hz. The subwoofer is supposed to handle components from 10hz-100hz. Effectively, full range speakers can make a subwoofer unnecessary. Sending 10-100hz components to non-full range speakers will simply result in extreme attenuation and possibly a little static.

To make matters worse, having both full range speakers AND a subwoofer will confuse the *** out of Windows. It doesn't know whether to separate out the low frequency components and send them to the subwoofer or mix them into the other speaker channels. The system doesn't know that your speakers aren't capable of reproducing the full range of sounds. What this translates into is audio streams that have a LFE channel (Low-Frequency Effect, aka the .1 in 5.1 and 7.1) will have it sent to the subwoofer as it should be but low frequency components will not be stripped from the other channels, effectively neutering the bass components of these channels completely. The correct thing to do is disable full range and let the audio codec move the components to where they belong.

Unfortunately most Realtek audio codecs do a piss poor job of resampling and remixing this audio. This tends to introduce a lot of noise into all of the channels that wouldn't be there on a discrete Asus or Creative Labs card.

I'm not suppost to put my problem in someone else thread but can you check out my problem?
http://www.tomshardware.com/answers/id-2291913/speaker-management.html