5.1 Analog (6 RCA jacks) Splitter Box ???

[Soundfield]

Well, all I can say is either you guys live under high voltage power lines and next door to massive radio transmitters or I’ve been very lucky wherever I’ve lived. At the moment probably all of my interconnects are 1m to 1.5m in length. There’s a tangled mass of them. I’ve don’t think I’ve ever had a problem with mains hum than wasn’t due to a fault and with all gains at maximum I can’t detect any noise anywhere in my system.

 

[DuncanS]

Well, all I can say is either you guys live under high voltage power lines and next door to massive radio transmitters or I’ve been very lucky wherever I’ve lived. At the moment probably all of my interconnects are 1m to 1.5m in length. There’s a tangled mass of them. I’ve don’t think I’ve ever had a problem with mains hum than wasn’t due to a fault and with all gains at maximum I can’t detect any noise anywhere in my system.

Neither have I. I did get mains hum in one bedsit at the very top of the house that I lived in as a student, but there was rather a large voltage difference between earth & neutral! and in the same bedsit I wondered why I could hear the fire service radio messages when playing an LP, then I drew the curtains and looked out there were 2 fire engines on the other side of the road putting a fire out in the building opposite.

 

[LuvMyQuad]

So I needed a fast cheap 6 channel RCA switch for combining 5.1 audio. I bought two 4 in x 1 out composite AV boxes. passive units. After I ordered them, I wondered about the specs that were published for it:

Video Input level resistance: VS0.8-1.0Vp-p/75©.
Output level resistance: VS0.8-1.4Vp-p/75©.
Support: 50Hz-5.5MHz .
Input connector: 4.
Output connector: 1 .
Audio Input level resistance: 2V(RMS)/45©.
Output level resistance: 2V(RMS)/1K©.
Support: 10Hz-20KHz, 0dB .
Input connector: 4(L+R) .
Output connector: 1(L+R) .

Why specs for a passive switchbox? OK. So when they get here Ill open them up and see what's inside. If I see any hint of circuitry, Ill just order another and use just the audio sections.

This is what is inside:

How can those specs jive with the photos? Its just mechanical switches, jacks and foil traces. Am I missing something?

 

[par4ken]

The specs are really meaningless just there to assure a customer that it will handle the normal audio and video signals. "level resistance"? Poor translation from Chinese!

Composite video has one video convection, usually yellow jacks plus two more for audio.. Component video has three connections for video plus two more for audio. From the picture I can't tell exactly what that is but it doesn't look like the switch's have enough contacts (5) for Component or (6) for Component + Composite., to be useful for 5.1 audio.

 

[mandrix]

Looking at another thread the other day, and curiosity, had me look for 5.1 analog switches. I also found one that would do 5, but not 6 (5.1) as someone mentioned.

I found none, but I think I noted there are a few tutorials on the tube about making switches using relays. Not specifically 6 channel, but to extend them would not be a problem.
Many relays are actually DPDT, (double pole, double throw) which means e.g. that one would do stereo, two Quad, three 6 (5.1). They are pretty cheap on Ebay, etc, and you could probably find push button switches or selector switches if you like them better, project boxes, power supplies, etc.
The relays are simple enough for a home made project but have the advantage over other solutions ("fancier" circuits with mosfets) for the non-pro duffer like me in that you don't need a EE degree to figure out anything too complex. Plus being relays (switches) they will just pass the signal without any processing at all. It's basically connecting all the components and soldering wires between them on a board and sticking them in a box with a small appropriate power supply to drive the relays.

I think I've about talked myself into building one. It's more a matter of time than anything else, and though I had Industrial Electronics courses years ago (DC) studying theory, breadboarding circuits, building a radio, etc, that was in the late '70s! But thankfully we have YouTube these days.

 

[LuvMyQuad]

The specs are really meaningless just there to assure a customer that it will handle the normal audio and video signals. "level resistance"? Poor translation from Chinese!

Composite video has one video convection, usually yellow jacks plus two more for audio.. Component video has three connections for video plus two more for audio. From the picture I can't tell exactly what that is but it doesn't look like the switch's have enough contacts (5) for Component or (6) for Component + Composite., to be useful for 5.1 audio.

Each box can switch 3 channels, audio left, audio right, composite video. I have 2 boxes = six channels.

 

[mandrix]

So I needed a fast cheap 6 channel RCA switch for combining 5.1 audio. I bought two 4 in x 1 out composite AV boxes. passive units. After I ordered them, I wondered about the specs that were published for it:

Video Input level resistance: VS0.8-1.0Vp-p/75©.
Output level resistance: VS0.8-1.4Vp-p/75©.
Support: 50Hz-5.5MHz .
Input connector: 4.
Output connector: 1 .
Audio Input level resistance: 2V(RMS)/45©.
Output level resistance: 2V(RMS)/1K©.
Support: 10Hz-20KHz, 0dB .
Input connector: 4(L+R) .
Output connector: 1(L+R) .

Why specs for a passive switchbox? OK. So when they get here Ill open them up and see what's inside. If I see any hint of circuitry, Ill just order another and use just the audio sections.

This is what is inside:

View attachment 76269
View attachment 76270

How can those specs jive with the photos? Its just mechanical switches, jacks and foil traces. Am I missing something?

I can't see the components too clearly, but it looks like they are using relays. Thats good.

 

[par4ken]

Looking at another thread the other day, and curiosity, had me look for 5.1 analog switches. I also found one that would do 5, but not 6 (5.1) as someone mentioned.

I found none, but I think I noted there are a few tutorials on the tube about making switches using relays. Not specifically 6 channel, but to extend them would not be a problem.
Many relays are actually DPDT, (double pole, double throw) which means e.g. that one would do stereo, two Quad, three 6 (5.1). They are pretty cheap on Ebay, etc, and you could probably find push button switches or selector switches if you like them better, project boxes, power supplies, etc.
The relays are simple enough for a home made project but have the advantage over other solutions ("fancier" circuits with mosfets) for the non-pro duffer like me in that you don't need a EE degree to figure out anything too complex. Plus being relays (switches) they will just pass the signal without any processing at all. It's basically connecting all the components and soldering wires between them on a board and sticking them in a box with a small appropriate power supply to drive the relays.

I think I've about talked myself into building one. It's more a matter of time than anything else, and though I had Industrial Electronics courses years ago (DC) studying theory, breadboarding circuits, building a radio, etc, that was in the late '70s! But thankfully we have YouTube these days.

There were some remote controlled boxes for stereo and for six channel listed on eBay. Even some with passive volume controls. They all switched using relays. I haven't looked in awhile but being from China they were rather inexpensive. I don't recall how many inputs though.

 

[par4ken]

I can't see the components too clearly, but it looks like they are using relays. Thats good.

Those are just push button switches.

 

[par4ken]

Each box can switch 3 channels, audio left, audio right, composite video. I have 2 boxes = six channels.

That'll work it's just slightly inconvenient to have to switch two boxes.

 

[LuvMyQuad]

There were some remote controlled boxes for stereo and for six channel listed on eBay. Even some with passive volume controls. They all switched using relays. I haven't looked in awhile but being from China they were rather inexpensive. I don't recall how many inputs though.

When I looked I did not see a single switchbox that could be used for 6 channels

 

[par4ken]

When I looked I did not see a single switchbox that could be used for 6 channels

They used to be there. Maybe not just a passive switch box but a remote volume control with switched inputs. In addition to seeing six channel ones I also remember seeing some meant for balanced stereo that could have been used for 4 channel.

A quick check and I don't see any either. There are lots of remote stereo motorized volume controls though with relay switched inputs.

 

[mandrix]

Those are just push button switches.

I can see the push button switches. I was thinking this was a powered unit and wondered if the components in the top pic were relays.

OK I blew it up, I can see it a little more clearly now. My bad.

 

[LuvMyQuad]

This is a contender for a remote controlled active unit. I may look into it some day. Boonie you can get it without the case for pretty cheap.

25.65US $ 5% OFF|5.1 channel audio switcher 2 input 1 output audio input selector 5.1CH audio switcher board|Amplifier| - AliExpress

 

[mandrix]

This is a contender for a remote controlled active unit. I may look into it some day. Boonie you can get it without the case for pretty cheap.

25.65US $ 5% OFF|5.1 channel audio switcher 2 input 1 output audio input selector 5.1CH audio switcher board|Amplifier| - AliExpress

I really need one that can switch 3x5.1. If you run up on one cheap, let me know?
I need to switch between 2 pc sound cards and an old Oppo I keep on my desk..

 

[Soundfield]

This is a contender for a remote controlled active unit. I may look into it some day. Boonie you can get it without the case for pretty cheap.

25.65US $ 5% OFF|5.1 channel audio switcher 2 input 1 output audio input selector 5.1CH audio switcher board|Amplifier| - AliExpress

It looks wonderful. Not only has it got a lovely hole in the front panel that you can see an LED through (obviously held in place by that nice bolt that obscures the legend!)-

but it will also handle all your Dobly signals -

and in Digtial which is good to know. Clearly a quality product.

 

[LuvMyQuad]

Gotta love those Chinese product descriptions.

I do wish there was a higher quality option. But I haven't found one.

 

[MidiMagic]

I just bought two of those at WalMart.

Does anyone know if the composite connection can be used for a third audio signal?

 

[Soundfield]

Gotta love those Chinese product descriptions.
I do wish there was a higher quality option.

It will probably give weeks of trouble free operation!

 

[LuvMyQuad]

It will probably give weeks of trouble free operation!

OK, OK, you talked me out of it.

I just bought two of those at WalMart.

Does anyone know if the composite connection can be used for a third audio signal?

With the pair I have I cant see anything except jacks, switches and foil traces in the signal path (see photos above). So I cant see why it couldn't be used for audio.