45 Type Push/Pull

Apprently they are rare- I have a friend that made a custom PP2a3 that could be converted to PP45 (I already have an SET 45 from him which is great- it is an awesome tube), so I am curious how it would sound as well. I can only guess that if the reason for wanting more power from the 45 is why the reason to creat a PP version, at that point people might be thinking a 300B instead at 8+ watts, hence the popularity of those amps. It would be great though, to see more 'all-out' 45 PP designs...

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.