Single Ended vs Balanced Output Gain

RCA vs XLR,the sound is also different. The mid sound in RCV connect will be outstanding, while XLR high,mid,low will be even.

I try to connect RCA pre to XLR amp(use RCA to XLR cable ),and the sound is like some mixed,finally I give up that cable. 

My opinion is that choose all XLR or all RCA and will give you best sound.

For me,I am really interested in vocal jazz and I think RCA system is more suitable as the mid vocal is just in front me while all  music instruments are step behind,which is really like the small band in the nigh club. I love it.

The most important thing I forgot to mention is that my RCA pre get perfect sound in my point of view,if I changed the pre, the sound is different. I also try RCA to xlr cable, the sound is also different.I will stay with this pre,that's the reason, and this pre does not have xlr port.

I know for sure XLR system get good sound, and get big sound , (I mean the sound get spacious) and get high,mid,bass in balanced. But in reality, it won’t win in all situations.

In my case, I listen vocal Jazz 99%, I want a low voice most of the time as I do not want to disturb kids learning.

I want the singer voice outstanding among all sound.

So in this case, definitely go RCA connection.

Make things simple,what I talked about  is real XLR amplifier port and RCA port.

It is real circuit inside the machine.

Now on first time,I really  feel the taste of  the  amplifier, the tone of the amplifier is so important,which I can not change anything,even the cable.

My pre is Rega Cursa 3 ,or Audio research LS25 MK2

Cursa 3 is RCA only

LS25 MK2 has XLR or RCA

My power amplifier is Audio Research VT100 MKIII, or REF 75se

VT100MKiii have rca and xlr

REF 75se is XLR only

When I listen to vocal Jazz,the only good result is 

Cursa 3 + Vt100 MKiii with rca connection.

I try rca to XLR cable with VT100 MKiii XLR port or REF 75se

the sound becomes different.

The only ok result is LS25MKii + REF 75se,but not good result,the sound is much modern,the jazz I listen is not like the jazz in the nigh club, but a group youth people dancing  on the stage. 

That let me think of conrad johnson fans,they stick to rca connection and do not affect they enjoy the music. If some one said the XLR is so advanced,It is nothing to me here. I can not listen over 1 hours with XLR connection while I can listen as long as I have time with  Cursa 3+ VT100 MKiii RCA connection.

My speaker is focal 905,which is not expensive,but very very good.