How Do Amps Affect Soundstage?


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

My DAC, premamp, and amp combo (all tube) throw a nice soundstage.  If I substitute (at least some) solid state stereo amps, soundstage is constricted.  If the amp is basically just increasing the signal that it is receiving from the preamp, I don't get how the size and shape of the presentation is altered materially from what the preamp is delivering. (I get that the signal could get distorted, etc.).  How does the amp play such role?  And do monoblocks enjoy any design advantage in maintaining the soundstage received?  Thanks.

mathiasmingus

Amps do affect the sound stage quite a bit.    I have found overall noise is a significant factor in soundstage width and depth.  Quieter your components usually contribute to a larger, more impressive sound stage. 

I have done my own listening test using up to 4 different Amps - using the exact same equipment, locations, music and just switching Amps.  Yes Amps can make a huge difference.  My Brystons 4BSST series produced the tightest most stable  imaging and sound stage.  They also had lightening fast response and slam thru my Maggie 3.7i.  My BAT 655SE produced deeper and better definted bass and seemed to have endless power.  In most ways the BAT are more pleasant to listen too, but they just don't hold imaging like the 4BSST.  I'm just guessing here and I'd love to know if lower frequencies maybe don't give us the same imaging clues as higher frequencies.  Maybe the BAT Amp's low frequencies emphasis drowns out the mids and highs that are more important for imaging.  

Yes some amps comes close to getting most right and they are generally more expensive. My final test would be how musical they sound and how enjoyable and involving they are