PLEASE match Advice Pass Labs X350.5 (20k) to Hovland HP-100 (2500ohms) Miss-match ???

I can agree with jahatl! Get a CJ ET-7se and be done with it. One of the top 5 preamps in the world today. GAT 2 being the other one. Cj has the prat thing going for it which makes other preamps sound less analog!

If your speaker is neutral u dont need all tubes. Cj pre with pass amp great combo. If you get tube pre and tube amp. You will lose prat & fine detail. Nuances! I had set before sounds nice but loss of fine detail and bass dynamics. But to be fair my speakers weren't really efficient.

 For the most part I don’t necessarily think it’s about tube and solid state. I totally disagree that you lose fine nuances with Tubes in fact I would tend to say it’s the opposite. One thing I have never heard solid-state do as well as Tubes is the holographic imaging thing. 
 So even though in my first sentence I say it’s not about one versus the other then I go on to say that I prefer Tubes LOL.Maybe I just haven’t heard the right solid-state stuff although I’ve heard most of it.
One thing I had a question about is earlier on in this thread someone mentioned to stay away from a cathode follower because of rising impedance Or something like that. My understanding was that a cathode follower is there to make the unit able to drive the next stage without mismatch problems? Is there something I’m missing?

I agree analogluvr! I was trying not to piss off tube afficianos! 😁

That's why I love cj only one tube rest is with good parts and volume control. I had the highly touted LTA MZ2. It sounded nice, did layering was airy & somewhat rounded. But lacked prat, transient bite and fine detail which gave CJ an edge in dimensionality. Eg. Snare kit being hit sounded more realistic projecting out 360 degs.

So the the point with a tube preamp with a cathode follower is they will typically (nothing is always) have a higher output impedance or one that rises quickly and/or both typically and this will cause a poor impedance match with a said matching ss amp.

So
with a preamp the output impedance rule of thumb is the lower, the better.

The simplified reasoning for this is the minimum of a 10 to 1 impedance match you want for your preamp to your amp.

There are many technical reasons for this but to make it easy to understand just know as a rule of thumb the minimum is 10 to 1 but to have more is better.

Why is this? Mainly to keep from having your bass roll off or other roll off issues.

So if the output impedance of a solid state preamp is 100ohm (SS preamps are typically lower than tubes) and the source (input) impedance of a solid state amp is 30k then you know you are good.

Why because 10 to 1 or 10 x 100ohm = 1,000ohm. 1,000ohm is much lower than amps input impedance of 30,000ohm or 30kohm. 

In this event you will be covered and good to go.

You will have your 10 to 1 covered via (10 x 100ohm) being 1,000 which is well under the 30kohm (30,000ohm). Remember the more head room the better. Here your amp max is 30,000ohm and you are only at 1,000 so you are in great shape.  

Now the idea is that a tube preamp with a cathode follower will have a much higher output impedance. Also, the impedance is not only much higher to start with but also rises much quicker also so its double trouble.

Lets say for this example this example the tube preamp with cathode follower output  impedance is 3,000ohm ohm. The Solid State preamp was only 100ohm. These are common numbers of tube and ss.

Big difference here. My SS preamp has an output  impedance of .5ohm which is nice and super low.

As a rule this is why SS preamps and SS amps work well together. Same said for tube preamps and tube amps. The output  impedance of tube preamps is high but many times the tube amps source impedance or input impedance is equally high to form a good match as such as 80k or 100k so it can handle the tube preamps higher output impedance.

This is why people say that tube preamp and especially tube preamp with cathode followers can be tough match for ss amps. Because tube preamps with cathode followers typically have higher output impedance and many (not all) solid state amps do not have very high source impedance to cover the 10 to 1 delta.    

So back to our tube preamp with cathode follower example that has an output impedance of 3,000ohm. Take the 3000ohm x 10 and that is 30,000ohm or 30k.

Your ss amp has a source impedance 30k and this puts you right up against the ss amps source impedance of 30k.

This you might be able to squeeze by with but not  ideal. The problem is like I stated before tube preamp with cathode follower not only starts high but also rises. At some frequencies it could rise to 5,000 or 6,000 and now you do not have the 10 to 1 covered and you can get bass roll off and/or top end roll off or both and now for no other reason than a improper  impedance match your rig will not provide anywhere near its potential.  Never mind how great each preamp or amp may sound if they don't match electronically your rig will be flat and rolled off and has all kinds of problems.

I hope this hacked version helped clear some of this up.

Thanks