Greetings from the UK!
 
I've just got through the epic 81 page thread on the JVC RX700 and RX900, and I've ordered 2 pairs of RX700 for me and my other half. The thing is, where I live speakers are not always possible, so I wanted to be able to have some late night listening sessions with her through my system. Currently it's a Marantz CD63 SE KI cd player and Onkyo TX8050 receiver (100wpc). I want to be able to run both headphones through the amps headphone socket, but I've read that a Y cable can degrade sound quality. Will it just mean lower volume, or an actual decrease in quality? Is there a way of combatting this relatively inexpensively? (Perhaps a FiiO 5 or two somewhere in the chain)
 
(Online specs put the RX700 at 48ohms)
 
The cable I've bought
http://www.amazon.co.uk/Ixos-XMM125-3-5mm-Audio-Adaptor/dp/B003L6MTI6/ref=sr_1_1?s=electronics&ie=UTF8&qid=1331622753&sr=1-1
 
 
 
Thanks

obviously it'll decrease volume if you try to run two headphones at once, but as far as sound quality, as long as it is built well there shouldn't be and problems.  But if there are any noticeable problems you can always make your own y-splitter.

Thanks
 
I'm not sure how linear things are, but for example, the amp goes up to 80 on the volume, and with one set of RX700's in now 25 is about perfect, so as a rough guide, double that to 50 for both cans running and based on that there'd still be plenty of volume left to play with and thus power and quality
 
Or so goes my theory
 
I know how much difference speaker cables make on my home hifi, so how would you make a Y cable? I'm fairly new to this

Making your own interconnects can be simple if you have your own soldering iron, if you don't have one then you need to buy one...
 
get one meter of this
http://www.qables.com/shop/index.php?main_page=product_info&products_id=575
 
one of these
http://www.qables.com/shop/index.php?main_page=product_info&products_id=547
 
two of these
http://www.qables.com/shop/index.php?main_page=product_info&products_id=366
 
i'll give you the short short version of how to make a y splitter.   Cut/ strip down the canare cable to the main 4 wire, cut that in half so you have 2 pairs of 4wires.  Solder 2 wires to left, 2 to right, and 4 to ground on the male plug,  Then solder each left cable to the their own female jack. Do the same for right wires.  Then solder 2 of the grounds to one female jack and the other 2 to the other female jack.  done.  There's more fancy things you could do like braiding the cable and covering it in expanding sleeve and shrink tube-ing the split but that's extra stuff.
 
with shipping this will all be about 18.41 euros

Running a y-cable will have an inverse of the effects of going full balanced on a single ended setup.
 
Balanced setups have less crosstalk, more power available to each channel since there is one driving element (whether tube or opamp) per channel, and I think it just plain sounds better by 10% when you go balanced.
 
So I'm guessing you're doing the reverse of that to a single ended setup, but who knows, you might come out sounding exactly the same at half the volume.