Tube power vs Solid state power, how much is enoug


Thinking about getting into tubes. My concern is how much is enough? From what I've seen, tube amp power is, on the whole, lower than solid state. I mean - ain't watts, watts? It's sort of confusing. Not being a big fan of non-dynamic (plannar, which there is nothing wrong with them, just not my cup of tea)speakers, I aim to wind up with either BW802, Legacy Focus/whispers, or the like. Unless I can find another way to achieve full range sound with a tube anp, I'll probably use(and really want to), my Krell with the tube, in a two amp configuration, driving one pair of the above mentioned units.

Shouldn't manufacturers just state voltage development or current ratings, instead of watts? Sure, more folks recognize the term watts, as it relates to power. But if it all comes down to how much voltage/current can be developed, and how quickly, then the term "watts", seems arbitrary. More so wehn you talk about "tube amps".

For the most part, I've long since quit looking at specs and just let my ears do the judging. That seems the best route. Problem with that is my ears usually end up arguing with my wallet, heart, and what is left of my brain. Some of these arguments are frightful. The winner is not always the ears. More times than not, the wallet wins. (not always), but usually. I try to leave the brain out of it as much as possible. Although, in this instance, I need to throw the brain a bone so I ask this question.

Just how do you figure out tube watts vs. solid state?

Please help my poor, ignored, seldom the winner, brain.

Thanks,
the brain
blindjim
My 2 cents (like anybody asked...)?

Trying to get disparate amplifier technologies to get along in the same system is challenging to say the least. You'll need some sort of electronic crossover, which is an additional (and audible) building block, and rarely has the correct crossver curves that a passive crossover does. So that will be a real challenge.

The speakers you listed are not that unfriendly to tubes, but beware the B&Ws that list nominal impedance at 8 ohms then wind up actully being 4 ohms in the woofer region, where most of the amplifier power is demanded. Not a good combo for a tube amplifier! The 802 is an example of such a speaker.

I strongly recommend that for any tube amplifier that you choose, contact the manufacturer and see what their experiences with the speaker you choose is. They may have some tips for you.

I also stongly advise you to heed this tip: try and get a speaker that is as efficient as possible! This was mentioned earlier in this thread and the value of this cannot be understated. If you choose a speaker that is 95db, it will require an amplifier of 1/4 the power to be as loud as a given combo with a speaker of 89db. Tube power in particular is difficult to make! So where a speaker of 89 db might need 200 watts in most rooms (I have found that to be the minimum in my room with such a speaker), you will find it much easier to find a musical tube amplifier if you only need 50 watts to make the speakers sing. In 200 watt amps, you can count the ones that actually sound like real music on one hand, and have a finger or two left over (there are no musical transistor amps, BTW...). But at 50 watts its a different story.

So be careful. Otherwise stand ready at the toilet to flush those dollars goodbye.
blindjim, your last post hit on an important point controlling output and that would be amp design details. Especially class a/b verses pure class a. For the audio rig i have VTL mb185s which are rated at 230 w/side running on 6550 tubes. My guitar rig is a boutique 35 wt el84 class A rig. The guitar amp is insanely loud. It will smoke 50 watt el 34 and 6550 based amps (ok that ain't a real big difference because to double spl you need to 10x output) and hangs perfectly with larger amps and the home rig. A lot of that is in how the amp is voiced as well...it cuts like a knife where as a home rig will be voiced more neutrally...at least you'd hope so.
Atmasphere,

Without sliding too far off field here, I'm curious as to the point where a speaker's high rated sensitivity is undermined by other criterea.

For instance, the Athena AF-2 is rated at 93db and sells for $600 a pair. Wouldn't these speakers do well handling 40W to 50W per channel tube amps?
93 db is a medium efficiency, not high. High would be over 100db. Plus you have to factor something else when you use the word 'senstivity'. It is NOT the same as efficiency.

The Senstivity spec is 2.83 volts measured at the speaker terminal and the sound pressure measured at one meter on axis.
Efficiency is the same, but measured with 1 watt at the speaker terminals.

If the speaker is 8 ohms, the two numbers are the same. If the speaker is 4 ohms though, now the actual efficiency is 3 db less! This is because 2.83 volts driving a 4 ohm load works out to 2 watts, not 1. All of a sudden 40-50 watts may not be enough!

I don't think the cost of the speaker plays a role here, although obviously if you are investing in a tube amplifier it only seems reasonable to use a speaker that allows the amplifier to perform in its best light...
Thank you. Everybody. I'm a bit late in responding to this line of thoughts and experiences, but I do thank you all.

I've chosen what I think is best for me.... tubed preamp, and Solid state amp. Seems the logical choice with fair benefits over strickly SS all the way. Not to mention the greater assortment of loudspeakers that are made available by virtue of the SS amp. I do love the combo I have now. When with speakers not known for their "Audiofool" (and yes, I'm including myself there too)qualities, but far more than adequate, colorless and homogenously coherent speakers... the sound I have is absolutely liquid. Detail, sweet, warm, rich all of these apply.... a good source as well adds to the mix... got one of those too. Finally.

Presently, I reside in the realm of "Man, that's really good!" everytime I turn it on and play it, now. of course, I would prefer to be in the court of "Man, that's really great." each time I play it, though.... and hence the quest for a bit more something edges me onward. Upward. More to the point, to the arena of "Man You sure must have more dollars than sense." which is where I would need to be to acquire the items on my wish list. Not necessarily the item one needs to obtain great audio but close to that , "...great!" sounding ball park. As evidenced by the current state of affairs I enjoy. I am not insatiable. I do have limits. I can be happy simply with the sound that continues to present itself as fresh, involving and musical at each sitting. I am certain also, that domain is soon to be one I enjoy routinely.... a few more peripherals, wires, and an upgrade in loudspeakers will, I am sure, do the trick.

So thanks again for your experience and wisdom, and interesting insights. Perhaps one day given my taste in sound, I'll go ALL tube.... for the time being with an amp of very good quality and less than two years old, I shall remain in this not uncommon space where glass and transistors, give voice to a most wonderful song.