45 Type Push/Pull

Deja Vu Audio makes 45PP

You can debate whether you prefer SET or PP amplifiers. They definitely sound different; I think each would appeal to some. Obviously, push-pull gives the kind of advantage in power that allows most to use the triode tubes with a real world loudspeaker.

The 2A3 has half as much power on paper in comparison with a 300B, but real world seat of the pants power doesn't translate, and the 2A3 often sounds like the bigger tube. The 2A3 is also the better sounding tube, and the 45 better still. However, the 45 makes half as much power as a 2A3, sounds/feels that way (figure 3 - 6 watts for push-pull 45 amplifiers), and seriously limits your loudspeaker selection.

I have a Deja Vu pushpull 45 amp. I like the sound. It has a tight, dynamic sound that is characteristic of pushpull. It is a VERY good amp. However, SETs do some things better (I own a parallel 2a3 SET amp). SET amps have a more natural delivery--no artificial edge to the initial attack, notes seem to bloom and expand into space, and the sound is more enveloping.

SET amps are often characterized as being a bit short on dynamics. Most often this is really about bass delivery. SETs don't quite deliver the same kind of "punch" to bass notes. I have mixed feelings on that issue. That same "punchy" sound of pushpull bass can sound a bit mechanical and artificial to me (sounds the same no matter the music), while SET bass tends to have more character (changes subtly with the music). But, the extra punch of pushpull may be what some music needs, so it is hard to say what is better. I currently have in my system a pushpull amp I really like (output tubes are Western Electric 349A), so I am not really in one camp or the other.

My only experience is with SETs. However, 300b SETs are much more tube dependent than 45 or 2a3 SETs. . . so much so that it is hard to make general comments about 300b SETs without mentioning the type of tube used.

Nice post Larryi, no single amp topology does it all.SET is`nt perfect across the board(what is?) but their natural presentation and non mechanical sound is more emotionally real and involving IMO.

Gsm18439(Gary) you`re right, it`s difficult to generalize 300b sound. Depending on the brand they vary from soft,slow and rolled off to simply brilliant sound(Takatsuki-TA) and all stops between these extremes. There are many flavors of 300b tubes.Of course the quality of the individual amplifier is another 'huge' variable.
Regards,