You can get active mixers as well ..ie; https://www.youtube.com/watch?v=NSowZcvoqr4

If only there was something for 5.1 systems

JayAlien wrote on 2024-01-11, 04:08:

If only there was something for 5.1 systems

could not multiple of these be used?

Sphere478 wrote on 2024-01-11, 04:19:

JayAlien wrote on 2024-01-11, 04:08:

If only there was something for 5.1 systems

could not multiple of these be used?

In theory, yes ... 5.1 is Front L/R + Rear L/R + Subwoofer channel ... so you could use 2 x the stereo mixers touched upon here, and 1 x 4channel mono mixer for the sub channel ... which would give you 4 x 5.1 sources, mixed to a single 5.1 output.

Also the center channel. It could be done with multiple units but it’s messy.
I’ve been on the lookout for a while, but there doesn’t seem to be 5.1 audio switches on the market.

JayAlien wrote on 2024-01-11, 05:12:

Also the center channel. It could be done with multiple units but it’s messy.
I’ve been on the lookout for a while, but there doesn’t seem to be 5.1 audio switches on the market.

I've only seen 2 x 5.1 source switches... ie; https://www.aliexpress.us/item/2251832692939592.html

giantclam wrote on 2024-01-11, 06:16:

JayAlien wrote on 2024-01-11, 05:12:

Also the center channel. It could be done with multiple units but it’s messy.
I’ve been on the lookout for a while, but there doesn’t seem to be 5.1 audio switches on the market.

I've only seen 2 x 5.1 source switches... ie; https://www.aliexpress.us/item/2251832692939592.html

Why not re-purpose a component video + L/R (analogue) audio + coax (S/PDIF) switch for analogue 5.1 audio ?

Like this one : https://www.startech.com/en-ca/audio-video-pr … ducts/cpnt410ir

EDIT: I just realized I have that exact one, 🤣 . I'm not currently using it .

EDIT 2: See also the similar Atlona AT-CV41R

Ah thanks. I do have a couple of component switches and I had considered them in the past. May have to revisit that project.

HDMI switches are getting around for cheap now, how hard is it to inject and extract audio in them do you think?

I've got a real fancy KVM I picked up some while back think I saw just a stereo jack on that, might be worth a try if you can grab one cheap.

Also in reserve is a rack/stack type AV source mixer think it does 5 or 6 to one, Realistic brand Tandy/RadioShack unit, that's in storage not sure what all it will do. At least stereo anyway.

4:1 serial switches should probably have enough lines to run thru, 4:1 parallel would def, but I had the impression that a 4:1 serial might be easier and cheaper to get than 4:1 parallel, lots of 2:1 around. But then you might have impedance matching and noise probs.

Also possible is just get a load of analog switch ICs and making an array turning things on with buttons and latches.

If you wanna go super low tech, you can find a junked projection TV and pull the input/output panel off the back, there's some that have like 20 RCA sockets, 2 inputs in both regular RCA and Component plus outputs etc, anyway, just wire that up and use it as a plugboard/patch panel with flying RCA leads.

I hand-made a custom passive mixer for my brother's setup. He has two PCs outputting 5.1, and wanted to also add an MSX that outputs mono. I took a couple of those small prototyping boards and populated them with 3.5mm jacks for inputs and outputs with a few resistors. The end result looks a lot like that commercial multi-input small passive mixer. Works great and is cute and needs no PSU.

Of course it has the same disadvantages of any passive mixer, but I personally can cope with those to save on one more power brick added over my outlet.

I use this 1988 mixer with a 486 and a Pentium 3.

BitWrangler wrote on 2024-01-12, 05:07:

HDMI switches are getting around for cheap now, how hard is it to inject and extract audio in them do you think? […]
Show full quote

HDMI switches are getting around for cheap now, how hard is it to inject and extract audio in them do you think?

I've got a real fancy KVM I picked up some while back think I saw just a stereo jack on that, might be worth a try if you can grab one cheap.

Also in reserve is a rack/stack type AV source mixer think it does 5 or 6 to one, Realistic brand Tandy/RadioShack unit, that's in storage not sure what all it will do. At least stereo anyway.

4:1 serial switches should probably have enough lines to run thru, 4:1 parallel would def, but I had the impression that a 4:1 serial might be easier and cheaper to get than 4:1 parallel, lots of 2:1 around. But then you might have impedance matching and noise probs.

Also possible is just get a load of analog switch ICs and making an array turning things on with buttons and latches.

If you wanna go super low tech, you can find a junked projection TV and pull the input/output panel off the back, there's some that have like 20 RCA sockets, 2 inputs in both regular RCA and Component plus outputs etc, anyway, just wire that up and use it as a plugboard

I do not recall having seen commercial products that do analogue 5.1 to HDMI. A DIY Raspberry Pi solution seems feasible, though.

Sphere478 wrote on 2024-01-11, 02:31:

There’s been a few threads asking about this, I got this 3.5mm jack mixer. It works pretty good!

Heads up. 😀

I used to shy away from passive mixers, but recently I threw one of these very things into a setup and I'm quite happy with it. It does the thing.

darry wrote on 2024-01-12, 15:40:

[...]

I do not recall having seen commercial products that do analogue 5.1 to HDMI. A DIY Raspberry Pi solution seems feasible, though.

Pretty much any modern USB sound 'card' has ADCs galore. Not at all sure about quality of additional A->D->A conversions though, and things could get very expensive if you need to do a *lot* of inputs.

Sphere478 wrote on 2024-01-11, 02:31:

There’s been a few threads asking about this, I got this 3.5mm jack mixer. It works pretty good!

Heads up. 😀

Got one of these passive mixers for my retro computer and I'm impressed, it can handle all four inputs from multiple sound cards quite well. 😁

Nice! :p

I wonder if there is a version with more ports🤔

Sphere478 wrote on 2024-01-21, 15:16:

Nice! :p

I wonder if there is a version with more ports🤔

There is the Edirol (Roland) M-10MX. It can support up to 5 stereo devices. It's also powered so there isn't any volume loss with an unpowered mixer. It even has a headphone jack and digital outs.

It's the most compact option I've found that can support 5 stereo devices.

Beyond that you're probably looking at rack-mount options such as this ART MX822 (8x stereo).

Are passive mixers safe? I was always told you shouldn't directly connect the outputs of two different audio devices.

Randomly came across some stuff in Elektor 303 projects book...
https://archive.org/details/Elektor_Electroni … ge/n13/mode/2up

Circuit 006 and 009 look interesting for these purposes. Note 006 is awkwardly named it's digital selection of analog audio and is also mono source to mono output so you'd need to double it up for stereo.