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Impressed with Tubes

For the first time, I auditioned a pair of Paradigm Reference Studio 100s run through a Rogue Perseus tube preamp & a Rotel RB1080 S/S power amp. Prior to that, I have never auditioned a tube preamp. Wow! What a difference! A richer, more integrated sound with the Rogue Perseus compared to S/S alternatives. Now that I am hooked on tubes, a few quick questions:

(1) Would there be a significant difference if I went with a tube power amp as well?

(2) Compared to the Rogue Perseus, has anyone had any experience with the Rogue Metis preamp?

(3) Other recommendations for tube preamps?

I am having a ball doing research for a new 2-channel system. And listening to a tubed component for the first time was a real treat!

Thank you for any help!

Kit
kitjv
pubul57
3,712 posts
 
I do have a tube amp (CAT JL2)that can handle low impedances, but it is expesnive and requires large transformers (the amp weighs 180 lbs!)and Atmasphere obviously uses a different approach. But nevertheless a higher impedance is always better for tubes and a smooth, linear impedance curve is important. I would think even a 4ohm nominal impedance would be ok, as long as the impedance curve was smooth, without large peaks and valleys at various frequencies - I think they call it impedance phase(?) or something. A discussion with your amp and speaker mfg always helps. I never understood much about the subject till Bobby at Merlin (speakers) explained some of this stuff to me and Atmaspheres contribution on the subject have always helped. The speaker in question seems to offer challenges to tube amps, even if they worked, they would "work" the tubes hard.
newbee
4,811 posts
 
Pubul57 - I would have no problem agreeeing with your comments about PP/SET amps interaction with speakers with a flat(ish) impedence curve, and there is no reason that a quality amp can't handle moderate speaker impedence dips, BUT one of the problems is that amps have varible output impedence to deal with that can be as problematic as speaker impedence (one of mine has a rise to 3.5ohms in the mid bass) so its important, at least on paper, to match the amps varying output impedence with the speakers varying impedence. Not a walk in the park if your looking for anything approaching ideal matching of amps and speakers without listening. FWIW.
pubul57
3,712 posts
 
I agree with you, and when you do hear an good match between pre/amp/speaker it suddenly becomes obvious that something good is happening, a sense of balance from highs to lows. One advantage to well designed integrateds.
phaelon
1,053 posts
 
OK, you guys are making me feel pretty inferior here. Are you telling me that I should be able to listen to a specific speaker/amp combo and then determine that somewhere around say 180hz there is an impedance mismatch of 2ohms. Please don't tell me you're telling me that,LOL.

Regards,
pubul57
3,712 posts
 
Not quite. But in speaking with your amp and speaker folks, you should be able to see if there are any red flags that would be obvious to them; if they are honest, then at that point you should not end up with any grave mismatch, and then it is up to you and your taste - there will never be one choice that works best for everyone....
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