My dac has only one output

[hex182]

My dac has one output and I need 2, one for my speakers and the other for my headphones. I don't ever need both to work at the same time and plugging and unplugging 2 RCAs at least once a day isn't a very appealing idea.
1. Would this thing degrade sound quality in any considerable way? http://www.ebay.com/itm/Audio-Video-AV-RCA-2-Port-Switch-Switcher-Selector-2-In-1-Out-Splitter-Box-CC-/181713026181?hash=item2a4ef0bc85:g:1SEAAOSwyZ5UomgH
2.If option one is not good are there any options below 20$? I am not interested in 100$ options because I could buy an other second-hand dac for that and not even in 50$ options because I would rather spend 100$ in this case and buy the other dac.

 

[fjrabon]

the item you link has two inputs and one output, which is the reverse of what you said you wanted.  Usually it's the amp that has multiple outs, not the DAC. Especially not multiple RCA outputs.  The DACs that have multiple switchable outputs usually have different kinds of output, ie balanced and unbalanced.  Pretty rare to see multiple unbalanced outputs on a DAC.  

 

[MindsMirror]

Use a Y-splitter cable to connect them, and just turn on the speaker or headphone amp depending on which you want to use. A splitter won't degrade the sound quality if it is just carrying the signal from a DAC to your amps.

 

[hex182]

1. fjrabon my bad, I just copied the first link I found, would a similar device with 2 outputs and 1 input affect audio quality in any meaningful manner? I'm interested in using this particular dac that has 1 output with L/R RCA jacks so the usualness or unusualness of the problem is not of much concern for me in this particular case.
2. MindsMirror if I would have had a y spliter around I would just try it and not ask but have you tried this? I was thinking about using a y spliter and even though I know little about audio or electrical engineering but it seemed logical to me that having something else connected would affect the signal even if it was power off.

 

[fjrabon]

 

1. fjrabon my bad, I just copied the first link I found, would a similar device with 2 outputs and 1 input affect audio quality in any meaningful manner? I'm interested in using this particular dac that has 1 output with L/R RCA jacks so the usualness or unusualness of the problem is not of much concern for me in this particular case.
2. MindsMirror if I would have had a y spliter around I would just try it and not ask but have you tried this? I was thinking about using a y spliter and even though I know little about audio or electrical engineering but it seemed logical to me that having something else connected would affect the signal even if it was power off.

A box is your best bet.  However, the good ones are somewhat expensive ($80 all the way up to $1500).  The bad ones can sometimes introduce minor amounts of noise into the system, especially if you have an "electronically noisy" environment around them.  They can also have ground loop issues.
 
A splitter cable is much more variable, and it depends on a number of factors: 1) what the output impedance of your DAC is 2) how close the input impedances for your 2 "destinations" are matched 3) how much gain you have available.  
 
In some cases a splitter cable is fine, you just lose half your power (which amounts to 3dB lost in the S/N ratio).  If your S/N ratio is great to start with, you may be able to deal with this.  If it's not great to begin with, then you could experience a loss of soundstage and resolution.  If your amp isn't particularly strong, you may also experience clipping.  It won't matter if the side you're using is turned on or off, as long as anything is plugged into the RCA it will pull the power from the line.
 
I'd say to start with a simple, well-made splitter, and if you notice sound degradation, then try a box.  Your best bet is to get a headphone amp that has RCA outputs though.  But I realize that may not be in the budget at this point.  Another option is a audio interface that are usually in the $150-$500 range.
 
The benefit of a box is that it will completely cut the unused output, meaning you won't lose the output.  An audio interface will actually amplify the signal back up so that both sources receive a full line level all the time.  A splitter will always cut the power in half (in a best case scenario, assuming relatively closely matched input impedances of the receiving sources.

 

[hex182]

Thank you for your time and the very detailed info!
I guess I will try the splitter, then the cheap box if I notice any problems and if that doesn't work as expected I'll just get one more DAC. Power or gain aren't going to be a problem and every out/in is RCA. The problem, budget wise, is that I've already spent more than I wanted to and I was hoping to use the internal ALC1150 with the speakers but it's just not the same and now I'm here looking for the solution.
 
1.Is it possible for a splitter or a cheap box to damage anything?
2.Do you think I have any chance with the splitter and the specs mentioned below?
Speaker amp Input Impedance: 10K ohms
Headphone amp Input Impedance: 50k Ohms
DAC: Line out impedance: 100ohm
3.Do these seem fine or are they complete s*** and can you recommend me anything?
http://www.ebay.com/itm/2x-RCA-Audio-Y-Splitter-Plug-Adapter-1-Male-to-2-Female-Gold-Plated-R-connector-/271932034026?hash=item3f50698bea:gWsAAOSwstxVNHkf

 

[fjrabon]

  Thank you for your time and the very detailed info!
I guess I will try the splitter, then the cheap box if I notice any problems and if that doesn't work as expected I'll just get one more DAC. Power or gain aren't going to be a problem and every out/in is RCA. The problem, budget wise, is that I've already spent more than I wanted to and I was hoping to use the internal ALC1150 with the speakers but it's just not the same and now I'm here looking for the solution.
 
1.Is it possible for a splitter or a cheap box to damage anything?
2.Do you think I have any chance with the splitter and the specs mentioned below?
Speaker amp Input Impedance: 10K ohms
Headphone amp Input Impedance: 50k Ohms
DAC: Line out impedance: 100ohm
3.Do these seem fine or are they complete s*** and can you recommend me anything?
http://www.ebay.com/itm/2x-RCA-Audio-Y-Splitter-Plug-Adapter-1-Male-to-2-Female-Gold-Plated-R-connector-/271932034026?hash=item3f50698bea:gWsAAOSwstxVNHkf

nothing would be harmed.  It will just mean that one source will get way more power than the other (though both will get less than if the system was only singly loaded).  I don't know the formula off the top of my head that will tell you exactly what portion of the DAC's line output will go to each.  Worst case is that one gets a line level that is simply too low and then the S/N ratio is really bad on the one with the lower line level going into it from the DAC.  If that happens you need a switching box that completely terminates the connection to the unused amp.  
 
I think the formula indicates that if your DAC outputs 2V, the speaker amp would get 1.7V (which is fine) and the headphone amp would get .3V, which would almost certainly cause the S/N ratio to be terrible and your amp might not have enough gain.  But I could be wrong about the impedance to proportion of output formula.  It will also depend on how your amps operate when turned off.  Some effectively draw power like they[re turned on, even if they're off, some will draw much less when turned off.
 
The splitters you linked are probably fine.  

 

[MindsMirror]

Pretty much everything fjrabon said about splitters is false. He is explaining it as if the Y-splitter put the devices in series, which is not the case. A Y-splitter connects the devices in parallel, so they each receive the same voltage. The impedance of the amplifier's inputs is high enough that it can practically be considered infinite, meaning practically no power is drawn by it, and it will have no affect on the signal going to the other amp. Your DAC's output impedance is several orders of magnitude lower than the amp's input impedance, so it doesn't come into play either.
 
I use a splitter to connect my sound card to my speaker and headphone amps, and I am an electrical design engineer. fjrabon is confused or doesn't know what he is talking about. Please do not spend $1500 or even $80 on a box to connect your DAC and amps, a Y-splitter like the one in your link will work perfectly.

 

[fjrabon]

Pretty much everything fjrabon said about splitters is false. He is explaining it as if the Y-splitter put the devices in series, which is not the case. A Y-splitter connects the devices in parallel, so they each receive the same voltage. The impedance of the amplifier's inputs is high enough that it can practically be considered infinite, meaning practically no power is drawn by it, and it will have no affect on the signal going to the other amp. Your DAC's output impedance is several orders of magnitude lower than the amp's input impedance, so it doesn't come into play either.

I use a splitter to connect my sound card to my speaker and headphone amps, and I am an electrical design engineer. fjrabon is confused or doesn't know what he is talking about. Please do not spend $1500 or even $80 on a box to connect your DAC and amps, a Y-splitter like the one in your link will work perfectly.

Thanks for the info! Glad somebody answered. I've had it be a problem before, though that was in a on stage monitor rig. Anyway glad the Y splitter should work.
For future info, the voltage is evenly split, right? Assuming a 2V out, each will now get 1V?

 

[hex182]

Thank you both for the input, I will get the splitter.

 

[MindsMirror]

For future info, the voltage is evenly split, right? Assuming a 2V out, each will now get 1V?

No. The DAC's output and the amp's inputs are all directly connected by the splitter, meaning the voltage at all three points is the same. If the DAC outputs 2V, each amp will receive 2V. If you disconnect one amp from the splitter, it doesn't make the other one louder.