Tube amps under $7500

@bdp24 Appreciate the warning. At this stage I should focus on amps with dedicated 4 ohm tap.

@passthedutchie Like you I would naturally incline to KT150s and wonder why the unit costs $400 less with these vs. stock EL34. 

Always a BIG fan of RM’s Music Reference work…including the power amps…but they are super neutral ….hardly overly tubey but very very musical… get fantastic RAM tubes for them !  9 mk2 or the 200. IF you have fairly efficient speakers or don’t listen loud, try to find the RM-10 version w hand wound by RM transformers…. a grail amplifier…imo….

Yes, as I mentioned above, OTLs may not work with a low impedance load.  Adding a transformer to lower the amp’s output impedance sort of defeats the purported advantage of being transformerless.  I personally don’t care about such theoretical problems and like the sound of iron anyway.  The M 60 and M 30 are very good sounding to me, although a touch lean (i.e., not warm).  The Joule Elecktra OTLs were warmer sounding, but some developed problems with their tube sockets over time so one must take care buying those amps.  The bigger Atmasphere amps sound very good and are a touch warmer, but even used they might be beyond your budget.  The bigger Atmasphere amps use more output tubes in parallel to increase output and this also lowers output impedance so they should be even more compatible with your speakers than the M 60 or M 30.  When they are compatible with your speakers, OTLs kick ass-they make the music so lively and dynamic without being harsh.

I had a Rogue ST-100 for a minute. It sounded terrible on my speakers, which are extremely accurate. I understand that Rogue overdrives the power tubes so you must constantly replace them at about six months.

I have two Prima Luna Dialogue Premium HP, the non-balanced pre-cursor to the EVO's. I loaded the HPs (I run them as mono-blocks) with KT150's. That gave me just below 200 watts for UL and nearly 100 for TR mode The PL is easier to work with as all the controls are accessible while playing. The auto adjust bias is a godsend as I don't worry about having the tubes adjusted properly.

I've had the PL HPs for six years now and I'm still running the same tubes. They must have lost something, but I still can play anything very loud with no fatigue. That's the best test I know for an amps usability. I had to stop listening to the Rogue after it was in use for an hour. I didn't keep it a month. Don't buy a Rogue.

Ayon Scorpion II

$5,500

www.usatubeaudio.com