Holographic Soundstage ?

I would like to share my observation and hopefully get some input from people who have the same interest.

My system consist of Wharfedale Opus 3 , Krell KRC-3 preamp, Krell KSA 150 amp, Chord Qutest DAC and a computer with JCAT USB EX running Roon/with LPSU from HDPlex.
I mainly like holographic soundstage and would be able to achieve a very good 3D soundstaging with my current Krell setup.
I decided to try out tube amp a couple days ago because I read through the internet and everybody told me that tube amp always have better holographic soundstage and 3D imaging comparing to SS amp.
So I order a Raven Blackhawk MK3 from Raven audio with 45 days home trial just to try it out. I was expecting a very holographic soundstage that will blow my Krell out of the water.
Well, I was so WRONG. The Krell combo actually has a deeper and wider soundstage comparing to the Raven.
The Raven also has some very weak bass comparing to the Krell which is more punchy and tonally rich textured bass.
I cannot understand why it happens. I am always under the impression that tube amp will always provide more holographic soundstage. Obviously, In my set up the Krell is superior when it come to 3 dimensionality.

I will keeping trying out the Raven Blackhawk in the next couple of weeks and if things are not improved. I am ready to return the Raven and perhaps trying out the other tube amps (or solid state amps) that can beat the Krell combo.

If any one has some idea of such a product, please let me know. I am looking for an upgrade right now.

@viethluu  @jjss49  is correct, it appears that the KEF loudspeakers are not a good load for this particular tube amp. If you look at the speaker you see that has a dual woofer array- so its nominally a 4 ohm load in the bass.

For this reason you should be using the 4 ohm taps IMO/IME. But its a simple fact that speakers designed this way are not intended for tube amps, which don't do well on 4 ohm loads. This is because the output transformer is less efficient on 4 ohm loads and not only will run hotter (absorbing amplifier power) but it may well lose as much as an octave of bandwidth on the bottom end!

If you really want to hear what tubes are about (and to also get lower distortion out of your Krells, which won't hurt) you would need to have a speaker that is at least 8 ohms in the bass to make a more valid comparison.

Put another way I suspect that because of the load of your speakers you are for more likely to get good results from solid state than tubes, but even solid state suffers because while it can drive the load easily enough, to do so it makes more distortion, which obscures detail (including soundstage information).
Prior to my tube amp set up I had a couple of well reviewed Krell integrated amps. My own experience was that my Rogue tube amps killed the Krell for (hologrpahic) soundtstage. Made the Krells sound dry and lifeless.Never looked back. Obviously the (tube) amp and speaker need to be well matched, maybe yours aren't, I do not know. Good luck.
The sound you're looking for is the synergy between your amp, your speakers, and your room acoustics.  You cannot just expect to pull out the ksa-150, and pop in the tube amp, and get that magic.  In fact, just swapping out the amp with another may require you move the speakers to readjust for the new soundstage.  You may want to ask the tube amp vendor the type of speakers that work well with that tube amp.  What speakers were they using to voice the amp during design?  Is there a list of speakers that they have tested well with that amp configuration?  Get that information to help you decide.  If you want to warm tube sound and retain the solid bass, bi-amp the speakers (not sure if that model of Wharfdale is capable.)  Drive the top with tubes, and keep the LF on solid state.  Adjust the speaker placement.  Maybe try out different speakers if possible.  Good luck.
Is your hearing holographic?  When your sound system can reproduce a single unamplified instrument so that you can't tell without opening your eyes whether you are sitting in an audition space listening to the instrument or in your listening room listening to speakers, you are there. 

I've experienced that rarely - once with Quad ESL 57s using Quad low output amplification.  I agree with the guys that have said it isn't the amplification train as much as it is the speakers.
I upgraded a 70 watt Conrad Johnson Premier 11a to a 500 watt Sanders Magtech amp. Sound stage grew by leaps and bounds! And as you mentioned with your Krell amp, bass is much better with SS. I still use Tubes in preamp (Hovland) and DAC (Lampizator) for added liquidity and musicality. Happy as a clam.