SET v. Pushpull


I did a search and didn't find any threads on this topic.  I am a newbie to tubes - I have a Tavish Adagio phono stage, and I am looking to add an integrated tube amp into the analog chain in my system - I have never owned one, so my knowledge level is low.  Right now I am running KEF LS50 speakers, but they are a little small for my listening area so possibly looking at larger speakers - I was very impressed by the Joseph Audio Pulsars I recently heard, as one example.

Anyway, most of the integrated tube amps in my price range are seem to be push pull, although the Line Magnetic is SET.  At a high level, I understand the push pull design gives higher output power than SET, but also higher potential for distortion.  

Any practical experience with the pros and cons of each?  And how important is this in the overall scheme, in real world applications?  Say, compared to the choice of output tube?

Thanks,


Tom 
tgr

Showing 1 response by sbank

Many excellent replies! 
You really want to do some listening to a variety of tube amps. Many tubes sound quite different and of course designs of a given tube do as well. There are a number of push pull amps that allow you to roll EL34s, 6550s and a few other variants.

SETs are a broad group and many are very low power(e.g. <10w). You really need a super friendly speaker(e.g. horn) to get the most of those. It all comes down to matching speaker+amp. 

A couple of personal experiences might be of help. I loved the sound of a number of SETs I heard, but I didn't like many of the horns and other speakers that were the best fit. That led me to 845 SET monoblocks from Dehavilland which run at 35w and allow you to open up your speaker options to many conventional speakers in the 93db neighborhood. Silverline La Folias were my best match with them. Merlin VSM Series also a good match, though lighter in the bottom end. 

When I had the opportunity I ran a pair of Atma-Sphere MA1 OTLs, which are another entirely unique class of tube amps that do many things better than most others again IF AND ONLY IF paired w/the right speakers (i.e. moderately efficient but more importantly with a friendly impedance curve. Some folks say they conquer that issue using items like Speltz Autoformers, to open up the speaker options to theoretically almost any impedance. Personally, the autoformers were not my cup of tea. OTLs had speed and clarity superior to most of the other tube amps I've heard of all other types. 

For me you've got to find the speaker you want first and then ask what amps will be a good fit with it, and consider a wide variety of topologies based on listening. If you can't audition, buy used so you can change gears without losing your shirt. Cheers,
Spencer