MT-ViKI MT-431AV 4 Way Switch Review

[musicforcities]

I kinda like all these little cheap device reviews, occasionally there's a gem that serves a purpose. Transparent functionality in audio doesn't have to equate to $$$$.

Agree. One needs these sorts of things from time to time, for example:

- bypass an AVR with external l/r amps for music listen (put a box like this between the avr and the amps, and between a DAC or audio preamp.

— occasionally listen to a turntable with phono preamp, SACD player etc within an otherwise streaming/server based system. Though a proper preamp is probably preferable.


A search on Amazon etc often turns up dozens of choices, some cheep as chips, some rather more expensive, and no way if any device is either great or at least “good enough” for one’s purpose etc.

In the case, the cross talk seems problematic but only if one is going to have multiple sources running at the same time.

 

[musicforcities]

It's most likely the wiring inside. If you measure with open inputs at a high impedance, any capacitance will give you major crosstalk.
It should have been measure with sources connected. Who listens to open inputs?

Can noise enter the active input through either unused inputs or used but inactive inputs? Guess one could use rca shorting plugs on unused ones.

I have had devices with cross talk between l/r channels.

 

[bgravato]

could one use the composite video for coax digital audio instead? Or for a subwoofer? Or would there be an impedance issue due to internal configuration?

Just curious.

Being a passive switch, it should be entirely possible. Depending on what exactly you're trying to achieve... I can't really think of a scenario where you'd want to use both stereo analog and coax simultaneously for the same source though...

Somewhat similar in case of subwoofer... though I can maybe imagine some possible (though unusual) scenario.

If you're switching between multiple coax sources, you can use any of inputs (R, L or video), you just need one of them and to make sure you use the same one for all sources and output...

 

[bgravato]

Unfortunately not for me.
I bought two 8-way switchers which appear to be of exactly the same design. My intent was to have one to control which device was playing, and one to control which device was recorded to.

Sadly, once I rigged the whole thing up I found that there was a ground loop (or some kind of noise) which went from inaudible to overwhelming as I moved from the lowest input to the highest on one of the boxes. It didn't matter what devices I was using, or which input they were on, that noise was always there as long as there was a device connected to the box.

Is this partially because I'm asking too much of a cheap passive setup? Probably, but the fact is that the internal design of the switch was clearly contributing.

The one I have (SkyTronic stereo audio source selector) has the ground shunted across all inputs and output... so I'm guessing yours has the same problem... If you have a multimeter just check for continuity on the ground connection (the outer side of the RCA connector).

If you have a source that has a floating ground it can cause nasty ground loops...

 

[Ralf Stocker]

I don't understand how you can only achieve -30dB with a mechanical switch? All electrical engineering laws must have been violated here. China trash!

 

[Hayabusa]

No, just unterminated open inputs

I don't understand how you can only achieve -30dB with a mechanical switch? All electrical engineering laws must have been violated here. China trash!

 

[Robbo99999]

A question regarding the crosstalk, which is the reason for the poor performance of this product. If you only have one input playing at any given time (ie you stop playing the other inputs) then crosstalk performance isn't going to matter because they'll be nothing playing on the other channels. Am I right? I feel a bit silly asking this question, but if you always make sure you only have playback happening on one input at any given time, then this device would be fine & crosstalk results wouldn't matter. Don't most people stop their other inputs playing back before switching?

 

[Hayabusa]

A question regarding the crosstalk, which is the reason for the poor performance of this product. If you only have one input playing at any given time (ie you stop playing the other inputs) then crosstalk performance isn't going to matter because they'll be nothing playing on the other channels. Am I right? I feel a bit silly asking this question, but if you always make sure you only have playback happening on one input at any given time, then this device would be fine & crosstalk results wouldn't matter. Don't most people stop their other inputs playing back before switching?

it all boils down to the question if the measurement was done with open inputs or not.
Please @amirm : can you tell us how you measured?

 

[zoink]

A question regarding the crosstalk, which is the reason for the poor performance of this product. If you only have one input playing at any given time (ie you stop playing the other inputs) then crosstalk performance isn't going to matter because they'll be nothing playing on the other channels. Am I right? I feel a bit silly asking this question, but if you always make sure you only have playback happening on one input at any given time, then this device would be fine & crosstalk results wouldn't matter. Don't most people stop their other inputs playing back before switching?

This is my unit, and I do have to turn off my tuner on input 2 while I am listening to another source on input 1. With the tuner off it is fine — the signal is clean to my ears. With the tuner on I can hear the crosstalk at a low level.

So yes, the crosstalk is audible even with a terminated input on both the selected and unselected channels (though not all inputs are terminated, perhaps the electrical engineers here can say if that would make any difference).

 

[Hayabusa]

This is my unit, and I do have to turn off my tuner on input 2 while I am listening to another source on input 1. With the tuner off it is fine — the signal is clean to my ears. With the tuner on I can hear the crosstalk at a low level.

So yes, the crosstalk is audible even with a terminated input on both the selected and unselected channels (though not all inputs are terminated, perhaps the electrical engineers here can say if that would make any difference).

Ok, so that is answered then
Cross-talk would be more with a not terminated channel selected ( as the input of the next device will have a 'high' impedance)
If unselected channels are not termintated makes less of a difference.
Then its still a big question how they made something failing so big time

 

[Robbo99999]

This is my unit, and I do have to turn off my tuner on input 2 while I am listening to another source on input 1. With the tuner off it is fine — the signal is clean to my ears. With the tuner on I can hear the crosstalk at a low level.

So yes, the crosstalk is audible even with a terminated input on both the selected and unselected channels (though not all inputs are terminated, perhaps the electrical engineers here can say if that would make any difference).

Yeah, if you turn off the input I'm assuming we can ignore the crosstalk measurements, because if there's no playback going on on the input from the the unselected input then there's nothing to "crosstalk with". I've got a cheap switching unit and I've tried turning on all playback on unused inputs to max and I can't hear anything on the active channel, so in the case of my switcher I'm supposing the crosstalk is fine.

 

[bgravato]

Inspired by this thread, I decided to run a quick test on my passive/mechanical switch/selector: SkyTronic Stereo Audio Source Selector (I don't remember how much it cost, probably somewhere between 5-15€, on Amazon, though this was quite a few years ago).

Regardless of having anything connected or not in other inputs I couldn't hear any crosstalk or leaks or whatever might be. Shall I consider myself lucky? I'd expect this to be the standard on a mechanical switch.

Only exception to this is if I connect a source that has a floating ground, in which case there can be some ground loops. This is because the ground pin (the external rim of the RCA connectors) are all shunted to each other (well Left and Right are separated, it's only within the same channel they are shunted across all the inputs and output).

 

[andrewskaterrr]

My first thought as well, especially since my son acquired three vintage consoles over the holidays that all have composite video, and the TV only has a single input (the composite-to-HDMI device I bought doesn't seem to work...).

If you want the best plug n play picture quality, get a RetroTink. I did a lot of research and they are the only ones that are completely PnP, and get you 90-100% of the absolute best quality you can get on the market. The new RetroTink 4K is crazy. I have the 5X-Pro and love it.