How Do Amps Affect Soundstage?

@mossyrocks I humbly apologize. Now I am going to offend you again :-) but it is Parts Connexion. I don't know Chris. If you told him the same thing that you said above, that

I was finding I could not get the system to 'juice.

Than perhaps what he meant is that the volume control design of the Ref 6 is such that it is the chief cause of a high-ish (footnote here) output impedance. Footnote-the output impedance of the Ref 6 is not, in relative terms for a tube pre, all that high.

The Ref 6 in balanced mode has output impedance of 600 ohms and the recommended load of the amp for the Ref 6 is 20k ohms or higher. In balanced mode the load of your amp is 30k ohm so you don't have a mismatch on paper but it the margin is not great. This would primarily affect frequency response though it also affects maximum power transfer.

So again, yes, the match is not great. But the OP was asking about soundstaging and you SEEM to be talking about power transfer with "I was finding I could not get the system to 'juice.

In my admittedly limited experience, amplifier soundstaging is most affected by channel separation/crosstalk (hence, all else being equal mono blocks better than true dual mono better than stereo), sufficient real power (voltage and current), and competent design. For a moderate power and price amplifier, see Stereophile and Audio Science Review test results of the Benchmark AHB2.

The more info I have the better thanks

Amplifiers matter because of noise, white noise accumulated through signal conditioning and amplification stages. Dead quiet to loud matters. Tubes, like jfets, and mosfets do not have a lot of current input and therefore have almost zero current noise. Voltage noise can be mitigated relatively easily. The listening  experience that enlightened me is from a Counterpoint Solid 2, blown up, that I fixed and changed minutely to drive, any speaker or simply weld to music. I was completely blown away after getting it going.. I wanted to listen to this thing, testing forever with my elac 6.2 debut monitors. My friend Dave, the amps owner was blown away too. Preamps because of noise, and of course speakers the biggest deal.      

Nelson Pass uses a technique of adding an out of phase 2nd harmonic distortion to his designs. This will give you more spatial information and the feeling that the notes are in the air.