How Do Amps Affect Soundstage?

"I'm not that technically strong on audio yet, so please refrain from mockery on this...."

I've been on Audiogon for just a few months.  This is one of the saddest comments I've read. 

This is an expensive hobby.  We are much more financially successful than most people.  And probably much better educated.  We should be better than this, welcoming new people not making them fell stupid. 

I've all tubes. I do find that they have a more pronounced three dimensional soundstage. It could be that they simply have a lower noise floor—allowing the tiny signals necessary for the most nuanced sound cues through. It could also be that the glass picks up sound waves which causes a slight reverberation giving the music a more echoic perception. 

Monoblocs sound better because there is no cross-modulation between channels. In other words, you get better stereo separation. 

I finally heard an amp paired with the 40.2 that actually made me want to sit and listen. The JFM. Sadly they don't give them away. 

It maktters , if you have a low budget amp say under $2k ,you will not get the budget soundstage and imaging that a good Solid state amp with bring 

which will have Mosfets, Fet, bipolors which as have some tube like traits .

IMO and many others a good SS amp , and Tube preamp is a classic combination 

a minimum of $10 k on average for a quality pre or amp ,

that would be -B class my audiophile standards. 

I agree with several of the above comments, and most seem to agree that the lower the distortion, the more accurately the source material, including the soundstage, can be reproduced.

Along those lines, I would say that vibration control, and especially of speakers, can also contribute to a better soundstage. Speaker vibration tends to produce distortion that is referred to as a "smearing" of the sound, and controlling it can reduce or eliminate the issue. Among other positives, I noticed a better defined soundstage after having employed Isoacoustic Gaia under my speakers.