Looking for a refined switch to toggle between two inputs for a DAC.
Thanks in advance for your suggestions.
Thanks in advance for your suggestions.
You want a commercial unit or to build one?
Basically, coaxial SPDIF uses an 75-ohm RF transmission line coax. If you want a mechanical switch and you want to keep impedances matched, then you may be looking at some money. If you want to do it yourself, the question is passive or active? Logic chips can be used as switches, but the 75-ohm line needs to converted to logic first, then after switching, it needs to be converted back to 75-ohm with a SPDIF transmitter.
A passive switch that ignores impedance matching could probably work in some cases, but may increase jitter even if it does work.
Basically, coaxial SPDIF uses an 75-ohm RF transmission line coax. If you want a mechanical switch and you want to keep impedances matched, then you may be looking at some money. If you want to do it yourself, the question is passive or active? Logic chips can be used as switches, but the 75-ohm line needs to converted to logic first, then after switching, it needs to be converted back to 75-ohm with a SPDIF transmitter.
A passive switch that ignores impedance matching could probably work in some cases, but may increase jitter even if it does work.
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Not sure what you mean by "do it yourself".
I don.t know enough to determine whether it needs to be active or passive.
"you have two SPDIF sources and you want to toggle between them"
Yes.
I don.t know enough to determine whether it needs to be active or passive.
"you have two SPDIF sources and you want to toggle between them"
Yes.
How long are the SPDIF cables, how long from the switch to the dac, or whatever the common device? Does it matter how much jitter is added?
"How long are the SPDIF cables"
No more than a few feet.
"how long from the switch to the dac"
the switch will be mounted on the DAC chassis
"Does it matter how much jitter is added?"
Yes
"You could use something like this (with some RF adapters from SMA to RCA, or to BNC):"
Found one for $10 on ebay. Cheap enough to try.
From the look of it, not sure how it toggles? Besides the connector adapters, what else does it need?
I am kind of a less is more kind of person, so, not sure this thing looks too transparent not to mention adapters etc.
Found one for $10 on ebay. Cheap enough to try.
From the look of it, not sure how it toggles? Besides the connector adapters, what else does it need?
I am kind of a less is more kind of person, so, not sure this thing looks too transparent not to mention adapters etc.
Radiall R570413000 RF Coaxial Switch 0-18GHz 28V 328243299136 | eBay
Same model number you suggested
Same model number you suggested
Good point about impedance. Most switches are going to be 50-ohm, except maybe for video which is 75-ohm same as SPDIF. Otherwise, baluns could be used before and after a 50-ohm switch to match impedance.
Maybe could try something like: 4 In 1 Out BNC Coax Composite Video Switch | eBay
Maybe could try something like: 4 In 1 Out BNC Coax Composite Video Switch | eBay
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Let me elaborate on my situation. I use a network renderer to provide a digitil signal to my DAC via BNC input.
I would like to add a another input that would come from a computer. I am manually changing input sources currently. Its not that bad as I only use the computer occassionally for streaming movies, youtube etc.. but... if I could add a simple and transparent switch (not another box or other active solutions) then that would be cool.
I don't want to compromise the current sonics as I have things sounding pretty darn good.
But, I'm not quite as picky with the computer source. Getting the 3-D imaging and a pristine decay just so, isn't that important w the computer... so not sure if there is a way to keep one signal unmolested by more switches or not. But if its cheap enough I can always give it a try and see (hear) how it goes.
I would like to add a another input that would come from a computer. I am manually changing input sources currently. Its not that bad as I only use the computer occassionally for streaming movies, youtube etc.. but... if I could add a simple and transparent switch (not another box or other active solutions) then that would be cool.
I don't want to compromise the current sonics as I have things sounding pretty darn good.
But, I'm not quite as picky with the computer source. Getting the 3-D imaging and a pristine decay just so, isn't that important w the computer... so not sure if there is a way to keep one signal unmolested by more switches or not. But if its cheap enough I can always give it a try and see (hear) how it goes.
I would use asynchronous USB, clocked synchronously with the dac clock. Add galvanic isolation followed by reclocking, and that's about the best we can do today. If using SPDIF, the only way to really de-jitter it is to use a good FIFO reclocker with the output synchronous with the dac clock. Anything else can be expected to produce some sonic compromise.
Thanks for your thoughtful reply.
I'm working on figuring out what Audio Note is doing (see picture in previous post).
I'm working on figuring out what Audio Note is doing (see picture in previous post).
Looks like Audio Note allows either SPDIF or balanced AES. Both use the same audio data with embedded clock. AES is the professional version for running longer wires and for use in more electrically noisy environments. AES also can contain different non-audio data, or not; IIRC it also uses a bit higher voltage signal. There is some interfacing info in the SRC4392 datasheet, starting on page 43 of the pdf. https://www.ti.com/lit/ds/symlink/s...09020&ref_url=https%3A%2F%2Fwww.google.com%2F