So Who has, or uses a Tube Hybrid Amp with Pre-Power in/out?

[MetalMogul]

I have an old Peavey Classic 2x12 Amp Combo that is a Hybrid amp with a 2x 6L6 power amp section and solid state preamp and has pre and Power amp in or out, not sure how that works.
If I run a tube preamp into the the pre-amp in jack of the hybrid Peavey , would there be any practical difference from that and an "all-tube" amp?

[Jazz P Bass]

Not too sure exactly which model you have.
Generally, the Pre jack 'sends' a signal out from the preamp.
The Power jack 'receives' a signal from another device.

A tube preamp will go in the Power jack.

[g1]

As far as the question about being the equivalent of an "all tube amp" that will depend on the actual power amp section of your classic.
Do you have the schematic?
Some models may have solid state portions of the power amp.
This is only really an issue if you are going for "no silicon in the signal path".

[fastfolkert]

Your preamp output should go into the power amp input of the Peavey.
Pls. note in some cases the power amp input has no volume control! Plugging things in can result in loud pops and clicks.
FWIW: The power amp of my hybrid Champ 25 is all tube (inverter + 2x 6L6GC)

My 2c

[Enzo]

Yes, you can divide the amp into preamp and power amp at the loop jacks. And you can use them separately like that if you wish. But it seems like a lot to hauls around just for the power amp and speakers.

It will have the pair of 6L6 tubes, but the phase inversion is transistor. So it would never be an "all tube" amp. That doesn't mean it won't sound great.