Help: Y-Splitter Split Before or After Amp

[Jacorby]

Hello, I`am sure this has been answered before, but it just read through a whole bunch of pages of posts, to find an answer and answered someones question even..   Maybe if i make this post rich enough it won`t be so bad.. See, I'm running out of time for this project!!
 
Primary Question, Question 1.  Post Topic
I want to know, coming out of my source (laptop's sound card), which might have only one line-out(not headphone out), should I y-splitter at the line level, to two separate headphone amplifiers, each powering one set of cans, or ysplit after amplification using the strongest headphone amp?  I think my amp should be powerful to drive two headphones....  So where should my splitting be?
 
 
I`ve read conflicting information on internets.
I've read that at the line level, splitting shouldn't make a difference, because the amount of loss would be nominal,  and made up by the end of the process, so long as it is just one split. And also because there will be amping afterwords.
I've also read that the line level is low already, and there will be losses seen by splitting it.. with even one split.
Maybe this is circumstantial?
 
 
Auxiliary, and supplementary questions!  Hook a fella up!
 
Question 2.
    If I'm doing a run, of say.. 10-30ft, should the y splitter be at the begining of the run(at the source), or split closer to the end of the run(near the speaker)?
 
Question 3.
    If i have to convert rca to 3.5mm, is it better to be done at the beginning or end of the run?
 
Question 4
    If a wire changes to a smaller/finer gauge, is it better to be done at the beginning, or end of a run
 
Question 5
    If after the y-splitting is done, and one amp, or headphone, is off,  does the y-splitting still make a difference?
 
Question 6.
    If ysplitting, should i use line out, or headphone out?
        I'm guessing line-out, but headphone has some amping I think.. 
        Though i understand the headphone amping can typically introduce noise.
 
 
Heres the gear, for your enjoyment, or angst, and the laptop, unfortunately, currently, has no line-out!! Which i understand is better than a headphone out, so im in the market to get one.. in a positional audio supporting soundcard..  Heres the run down.
 
Material
   Music
       Wav, (see local storage solution)
        flac (see local storage solution)
        Mp3 (rare)
        Internet Radio
        Super Audio Cd
        Audio DVD
        Genres
            Pop
            Opera
            Classical
            World-Music
            Dance
            Not sure what else Jazz maybe
  Video
    dvd delivered media (incl hddvd, blu ray)
    Local media files from digital store purchases (see local storage below)
    Streamed Video Services
    Possible Digital TV, IPTV

Computer
    Laptop Elitebook 8560W, i7-2760QM.  Powered currently using a nice, big, appropriate, separate, power factor correcting 230 watt laptop power supply: Ho ho ho!  That is the "HP 230W PFC AC Adapter", model HSTNN-DA12.  Or powered by extended life battery + Battery, + possible-future off-grid solution. 
    Storage medium for local files is a new Samsung Evo 850 Solid State Drive, housed separately in a docking station.
 
Soundcard Yet to be decided (must have positional audio support for headphones)
    is thankfully surrounded by the aluminum skinned; magnesium-alloy laptop enclosure, if internal expresscard (military grade?). 
    I`m not sure which Im going with yet...`but one of these
        Creative Xtreme XFI Notebook
          (in-expensive, on-hand, but off location, but without line-out, only headphone out.. laptop powered,  internal expresscard)
        Echo DJX
          (not sure if supports positional audio.. if it does, will likely invest.. for that "miracle dac", and line out, with volume control?, laptop powered internal expresscard)
        Creative Sound Blaster x-fi hd
            (external usb, separately powered(i think?))
 
I actually wouldn't mind an internal solution, since in this laptop the expresscard slot is enclosed in aluminum(military spec?), and pretty separate from other activity..   I guess it should be free from most computer interference, maybe better than a separate plastic case only a foot away..? And infact, protected from other non-computer interference, like the radio waves, additional ground loops?, power lines, ect, that fly around the location un-shielded structure, than say a less shielded implementation.  Typically, with the current cooling solution, my test system, the fan rarely goes on, some days never, dust free convection cools the system, currently, and the solid state drive is farther away in a docking station..  which might be modified for a new enclosure.  The power conversion, when done is far away, too,roughly: halfways down the 10ft cord.  but the power grid in this area i think is not so well tempered however..
 
Headphone amp 1
    z-2300 dual operational amp
        (z-2300 seems to have good power handling, and little distortion before clipping)
        If splitting is done post amplification, then this would be the amp..
 
Headphone amp 2
    An on-hand sony boombox,
        with an aux in and headphone out
        (wouldn't be used to power two cans, in the lin level solution it would be implemented to power the second headphone)
 
 
The z-2300 will be the one driving the two headphones.. i know this sounds crazy, but i have some faith in this amp., after all, this duel operation amp, which it feeds headphones (which have their own power amps), if no headphone are plugged in, otherwise later drives the power amps for the the split system, i understand.  So in effect, some motions would be following similar paths, splitting to different power amps...
 
This is just a trial system I'm building for someone.  We just have to get something on the ground rolling for now, and quick!!  Helpful input on the y-splitter condition would be welcome!
 
So what about it, looking at the rig here, where should I plan the splits?  This will help me pick more equipment! And are the Soundcard and headphone options going to make a difference?
Headphones yet to be determined.  Likely proxy in the akg k553, so after amping, or at least 1 k553, and the second set might be different.  I think the akg 553 is fairly easy to drive.  I know I'm asking lots!  But even the y-splitter info can be useful to me and others, in one place, well titled, wheres tags, and I have a nearly complete contribution up my sleeve, for a different topic.  So Ièm not all bad here, hahaha!  Help!

 

[MindsMirror]

 
Primary Question, Question 1.  Post Topic
I want to know, coming out of my source (laptop's sound card), which might have only one line-out(not headphone out), should I y-splitter at the line level, to two headphones amps, or ysplit after the amp?  I think my amp should be powerful..
 
I`ve read conflicting information on internets.
I've read that at the line level, splitting shouldn't make a difference, because there will be amping afterwords.

There is a trade off of cost and performance to consider. Splitting after the amp will require only one amp, but it will reduce performance. The two headphones connected together by the splitter will alter and degrade each others sound. You will also not have control over relative volume of the headphones. Splitting the line output to two amps will solve these problems. Sound quality wise, splitting the line signal before the amps is better.
 
 

  I've also read that the line level is low already, and there will be losses seen by splitting it..
Maybe this is circumstantial?

That seems like incorrect information. A line level signal will usually be higher in voltage than a signal powering the headphone (unless it's a very inefficient headphone), and will be much lower current (practically zero), meaning practically nothing is lost in splitting it.
 
 

 
Question 2.
    If I'm doing a run, of say.. 10-30ft, should the y splitter be at the begining of the run(at the source), or split closer to the end of the run(near the speaker)?
 
Question 3.
    If i have to convert rca to 3.5mm, is it better to be done at the beginning or end of the run?
 
Question 4
    If a wire changes to a smaller/finer gauge, is it better to be done at the beginning, or end of a run
 
Question 5
    If after the y-splitting is done, and one amp, or headphone, is off,  does the y-splitting still make a difference?
 
Question 6.
    If ysplitting, should i use line out, or headphone out?
        I'm guessing line-out, but headphone has some amping I think.. 
        Though i understand the headphone amping can typically introduce noise.

2. Splitting at the end of the run will require less cable, i.e. lower cost. Splitting at the beginning of the run would be similar in effect to using a thicker gauge cable, which could have some effect if the cable is transmitting power, but a line level cable is not (practically zero current), so you should just split it at the end.
 
3. This is essentially the same answer as question 2.
 
4. In electronics if you have components in series (like a small gauge cable followed by a thicker gauge cable), it does not matter what order they are in.
 
5. If you split before the amps, it wouldn't make a difference even if both amps are on. So turning one amp off or even unplugging it from the splitter wouldn't make a difference. If you split after the amp, definitely unplug the other headphone if you aren't using it.
 
6. Use the line out if you are splitting to two amps. Adding an amp before another amp will only degrade the sound.