amplifiers tube vs. solid state

Tubes in either your preamp or your amp can give you the best of both worlds.  Most people go with the tube preamp and SS amp, but I have done it both ways. I’ve been a tube guy and a separates guy most of my life, but have just recently gone to the dark side.  A SS integrated with KEF speakers and have mostly good things to say.

All the best.

The “classic” hybrid system combo is tube pre and SS power, but this setup can have consequences - for example, if the tube pre has high output impedance and SS amp has low input impedance (both common for each type), this can result in frequency response aberrations, especially bass roll off (ESR on coupling caps tends to rise as frequency goes low, and the resulting voltage divider eats up your bass response!). Tube amps tend to have high input impedance and SS pres have low output impedance, which is optimal for the voltage signal transfer (not power transfer!) needed there.

More significantly, if the output caps on the tube pre starts to leak DC (which some do after some years) and your SS amp is DC coupled, this can destroy your amp and/or speakers. With a tube power amp, those output transformers can save your speakers from a lot of bad stuff. An output transformer is a much better thing to trust than an output cap.

A very fine SS pre (which I assume your ML is) combined with a tube amp does not suffer these pitfalls, and is a great way to go! Tube amps, when engineered right, are also a lot more reliable than many audiophiles give credit to.

Sonically, this pairing can work out very well too. I think you get more of the “tube sound” from a power amp, depending on your choice to some degree.

I have done the SS preamp and tube amp thing.  Can be quite good if you find that great pairing. 
 

This is something where in home auditions are a must 

I do a tube preamp w/a SS amp. Luxman CL38Use and a Bryston 3B cube w/Aerial 5T speakers and a JL Audio D-110. 

As @mulveling mentioned… check the input impedance of the existing SS amp, and the output impedance of the candidate tube amp.

I run a tube pre now (one from 98 to 2022, and a different one since last year.)
Sonically they are similar.

I have run them into tube amp(s), Class-AB and Class-D and they all were pretty well behaved.