Tubes for Magnepan’s.


I think next up on my acquisition list is a tube amplifier. I'm not looking for the be all end all, cause I don’t think there is a definitive "Best", so am looking for as good as I can get for $3-4k.


Because tubes drive speakers so much more efficiently than solid state I am only looking for 40-50 watts to drive my modded Maggie’s, 1.7i's. (Or what you have when you add a new crossover and planer tweeters to 1.7i's.) Maybe 2.7x? I haven’t settled on that yet. And I have some Zu Dirty Weekend's upgraded to the max coming in in 2 months to replace my KEF's.

Anyway, I haven’t had a tube device since my Halicrafter short wave radio, and reviews are not the same as advice from people that own something. There is a Rouge Audio dealer in my area, last I looked, (opps, they no longer carry them), so I may have to go to another market to hear something, or get a try before you buy from a manufacturer or dealer.

You folks have taught me a lot, and I think asking users is the right thing to do on this change in direction.

Thanks in advance.
128x128william53b
Expecting a tube pre / ss combo to emulate a tube power amp is a fools errand. It could sound very nice depending on the power amp.
Expecting a tube pre / ss combo to emulate a tube power amp is a fools errand.

i agree with the gist of this comment, though calling it a ’fools errand’ is unnecessarily perjorative

a very clean extended tube pre (think upper echelon arc, cj, vac, herron...) mated with a very pure solid state amp (hegel h20/h30, pass, ayre, accuphase) can do wonders in a system where a tube power amp could be impractical due to cost, heat, weight, reliability, tube matching etc etc to drive demanding speakers - but know that a high performing tube pre is not cheap by any means

certainly a top level high tube power amp like the upper arc models will give a greater sense of dimensionality, depth of stage, air and nuanced tactility through the freq range 

all about managing tradeoffs and what the user's priorities are
Im thinking a couple of ma1 atmasphere monoblocks are one of the few that could drive Maggie's 
key point is that well built ss amps can double power output into 4 ohms versus their basic 8 ohm load rating... tube amps cannot do this and can struggle to deliver even the same power in 4 ohms versus 8...
Doubling power is not the same as that amp sounding its best.

The reason is distortion- in solid state amps, this tends to be smaller amounts of higher ordered harmonics. Our ears use the higher orders to sense sound pressure and so tiny amounts of that distortion is perceived as harshness and brightness- and quite literally is why tubes are still around.

Steve McCormick has made amps that can easily double power into 4 ohms. But he sent a letter to Paul Speltz (known for anticables and also the ZEROs which are an autoformer) describing how in fact his amps sound better driving low impedance loads using Paul’s ZEROs (www.zeroimpedance.com). I described why above.


Of course, if you have a set of ZEROs to work with your four ohm Maggies, then you can use a tube amp pretty effectively as well. We are in the same town as Magnaplanar and so have a lot of local customers who use our amps with them. Our amps don’t have an output transformer (hence the term OTL) but the combination works quite well. In smaller systems our M-60s get used with the ZEROs.


The bottom line here is that no matter what amp you have, if it is driving a 4 ohm load directly, it will be audibly inferior to how it drives an 8 ohm load or even 16 ohms. The ZEROs are a workaround for this problem.


I know people will say that a big enough solid state amp will do better, but it does not matter the amp, you will see in the specs that its distortion is higher into 4 ohms. Distortion causes colorations (like harshness and brightness); high end audio is all about getting away from that. If you are really stuck on a 4 ohm speaker, consider a set of ZEROs no matter what amps you have.