What to update first: pre or power amp?

I would usually agree with the above statement but, The Rogue 66( Providing it is working correctly) is a good unit. I feel that the 88 upgrade would be the better choice.

After much listening, borrowing friends gear, and getting my friends opinions, I have to say that in my opinion and most of my friends opinions, speakers and preamps make the most sonic differences in a system. I personally was shocked that preamps sound so different!
I think the weakest link in almost any preamplifier is the volume control system.Guy at Placette Audio will tell you the same thing about volume controls on preamps.
You have great speakers.I would personally upgrade the preamp first and see what happens.

I had the 88 and went to the M120's and saw a huge improvment. It just goes to show you that 2 people can do the same thing and not have the same sense of change.
I think the 88 is not a very good amp. I would switch amps first. And as soon as you can afford. Change the pre.

keep the pre you have and get a more powerful rogue amp. the martin logans need gobs of power, and although most goners seem to prefer cj over rogue, i think the synergy between two quality components of the same family give you a system where the whole is greater than the sum of its parts.

I had a Magnum 88 and went to Magnum 120s and there was not a big difference. My point is, I am GUESSING the M88 is a better sounding piece than the M66 pre and therefore agree that you should get the pre first.

There is the argument that since the power amp controls the speakers you may want to upgrade that first. Especially since you have tubes and they do not always control the bass that well, however, The M88 controlled my Maggie 1.6 quite well and is a fine amp so stick with getting the new pre.

all the best,

Phil

preamp and speakers are top for me...

Source first. If you don't have a good pre-amp, your amp and/or speakers (no matter how good) cannot make up for information that does not get to them. This has been proven, although some will undoubtedly disagree.

I am in the exact opposite camp as Stehno........Oh well such is life. The pre-amp has always had the biggest impact on my sytems performance, all things being equal, except for perhaps the speakers. However, having said that either component you upgrade (amp, pre-amp) is going to have a pretty significant impact. You mention your dealer does not stock the 140 does he/she stock or have as a demo the 17 and if so will he/she let you bring it home for a demo. No disrespect intended to Stenho we all have different experiences.

Chuck

Since, in my opinion, the amplifier is by far the most underrated component in any system, I would ensure that that part was taken care of first and then match everything else to the amp.

-IMO