In need of a simple router (possible bass management)

[mattiasNYC]

Hi guys,

I registered a long time ago but life got in the way of DIYing and didn't get very far. I'm now in need of a box to re-route or bypass a signal and ultimately do bass management.

I have 6 outputs from my LYNX TWO-B sound card. These outputs are usually L, R, C, LFE ("sub"), Ls, Rs. All are balanced line level and go to powered monitors. Subwoofer has L/R inputs and L/R outputs. It has a variable XO, phase invert (or whatever), and volume control. It is intended for L/R to go through the sub for a 2.1 configuration, or the LFE to go to either L or R only in a 5.1 or higher setup.

When using my DAW I'm able to work by treating the 5 speakers as full range and only sending dedicated effects in LFE channel to the sub. But I'm also able to do software bass management to check my work should I want to.

Watching movies my computer will decode to 5.1 but not bass manage (as far as I know). It's actually ok for most viewing and I don't have a big problem with it.

But listening to music in stereo I would like to extend the range using the subwoofer.

Short Term Solution: Simply build a switch to alternate L/R between going straight to speakers for 5.1 use, or into sub for XO and from there to speakers. Note that channel 4, LFE, is not sending anything in the stereo scenario. The build needs to be relatively cheap and simple to build.

Long Term Preference: Bass management for 2 to 5 channels.

Questions:

1) I'm thinking that my L/R will have a switch that would switch between sub/XO stereo and bypass for 5.1. If I do this I suppose the output of the sub is where the L/R would "reconnect" in bypass. So do the sub-outs need to be switched out in L/R bypass mode? And is a dpdt switch or rotary fine for this? Is anything else needed really (I'm thinking about potential pops when switching etc)?

2) My LFE (output 4) would have to be going into one of the sub's two inputs for when the L/R signals are bypassing the sub and sent straight to speakers. Would having this connected to for example Left at all times be a problem? (remember, this input would not carry signal to be summed with Left, it would be either LFE or Left).

3) Has anyone done any bass management around here? I've looked but haven't seen any finished projects.

4) What do I need to keep in consideration - if anything - in order to make a move to bass management easier if I start out with a simple switch only? (like, if switching more channels is easier and/or cheaper with relays, do I benefit from using that from the beginning? etc)

Thanks if you made it this far!

Any help is appreciated,

mattias

 

[mattiasNYC]

Please forgive me for bumping as well as providing a terrible sketch. All I have time for right now.

So is it this simple?

The inputs are balanced, so I'm wondering what type of switch I'd need. Ground (pin 1?) goes to chassis I guess, so that leaves two pins. Minus and plus (2 & 3 respectively?). When looking at my schematic it looks like DPDT the way I drew the left channel, so would I simply "multiply" that by two? Four pole dual throw?

As you can see the output goes to respective speaker since the sub has L/R in/out. So for channel 4 (3 not applicable) carrying LFE I'd simply route it into Right (in this example). So what's the best bet here; do I go with as many poles as possible (dual throw) or with multiple switches - for example 3 switches, one for each channel; Left, Right and LFE (4pdt, 4pdt, 2pdt)?

Again, sorry for not being better at this but I'm just starting out.....

 

[moamps]

Please forgive me for bumping as well as providing a terrible sketch. All I have time for right now.
So is it this simple?

Hi,
the schematic can be rearranged to save one switch, IMO.

You can try to find a cheap switch for switching two computer on one monitor, like this one
http://www.ebay.com/itm/PC-Computer-2-VGA-2-Serial-2-PS-2-Ports-Input-Switch-Box-2-way-/121085663998?pt=LH_DefaultDomain_0&hash=item1c31449afe
and use it for your purpose.

Regards,
Milan

 

[mattiasNYC]

Thanks so much Milan!

I think the suggestion you linked to seems like a great quick fix.

Just a few quick follow-up questions:

First; the connection from Left to 6 in S2 should happen in S1 as well, correct? It too needs to always be present at the output to speaker, either crossed over or full range.

Second; in the box you linked to, the kvm switch, did you mean that I'd use the circuit it comes with by just connecting to its inputs (different connector of course) or just the switch itself and rewire it on the inside? (Christ I need some coffee now...)

Third; If buying switch(es) I do need to double up on the actual poles though (compared to what I drew) in order to accommodate both pins for each channel, right?

 

[moamps]

First; the connection from Left to 6 in S2 should happen in S1 as well, correct? It too needs to always be present at the output to speaker, either crossed over or full range.

Yes, of course.

Second; in the box you linked to, the kvm switch, did you mean that I'd use the circuit it comes with by just connecting to its inputs (different connector of course) or just the switch itself and rewire it on the inside? (Christ I need some coffee now...)

First, replace the D and DIN connectors with stereo female jacks (for example), and rewire them to the switch.

Third; If buying switch(es) I do need to double up on the actual poles though (compared to what I drew) in order to accommodate both pins for each channel, right?

Yes, twist the wires from one balanced signal and use adjacent switch poles on the switch for switching one output. Be careful with the wireing, ensure that always + inputs from a balanced inputs is switched to the + output of a balanced output (same for - signals) to avoid "out of phase" routing.

Regards,
Milan

 

[mattiasNYC]

Thanks again.

My outputs are all XLR male, balanced line level. I'm thinking I'll cannibalize a couple of VGA connectors/cables and get some XLR m/f ones and just do the wiring on the outside of the box, if that suffices. Or is it preferable to go straight to the switch? I guess I'll just get the box and open it up and I'll see for myself what the better option is.