Is pre-out the same ?

Check the specks in the owners manual for output impedance of pre-outs. In general, since your intg. is solid state, solid state outs are low impedance- you should be good to go.
 " I believe that it is a 1 to 10 ratio of impedance from
preamp to amp ." - general rule for tubed pre to solid state amp matching.

 There are some here, that have had good results from a solid state preamp matched with a tube amp. A good consideration would be a tubed-hybrid amplifier matched with a solid state preamp. I have this combo.

Phooey,

Get a good RCA and give it a shot. I use a SS Mac with pre out all the time.. If it sounds good it sounds good.. :-)
No bad matches so far, just some better than others..

Regards

Thanks Folks ;
   I do have an ' all tube system ' so...ya !
But this is an all-in-one box for streaming and I really
like the simplicity of this thing . It all works together and is quite easy
to operate . It is my most used system but not the one for critical listening . 

PMM - owners manual ? we don't get no owners manual !
            That spec is not listed and I have 2 emails out to the                             manufacturer . They seem to be quite busy ! ? 

You all be safe now

Just plug it in and away you go......

It will be safe.

The 10:1 ratio has more to do with the frequency response.  The higher the ratio the better, but even a 5:1 won't sound terrible or break anything.