Tube vs. Solid State-Basic Question


So here I am with my first all tube amp, the Manley Stingray II. While I wait for my Merlin TSM-XMr's to be delivered I've got the Stingray connected to a pair of Definitive Technology BP7004 towers in my theater room. I also ran them with a few other amps....testing them with a Cambridge 550A amp with 60 watts. I was able to play the speakers with the Cambridge well enough, but on tough passages at higher than medium volume the sound got congested and even distorted above that level.

So now I connect the new Stingray, switch to Triode-Mode (just 18 watts) and I get equal volume (or more) with beautiful sound, dynamics and imaging....and that's 18 watts in triode mode! The extra watts of the Cambridge did not appear to be of any use. What's up with that?

So....can some folks more educated on tubes explain to me....like I'm a two year old how the low powered Stingray plays so well with so little power?

Next up was to switch out of the triode mode and get the full 35-40 watts from the Manley which could drive the speakers very loud in my fairly large theater room. While I'm VERY happy with the Manley Stingray, I'm also a bit confused at the power the thing seems to have in spite of it's lower power. In fact my fat Denon receiver (110 watts) cannot keep up with the Stingray.

All comments welcome!

Bob
robbob
I have one additional comment to add in addition to what's been offered already. It is my understanding that when a tube amp clips, meaning the volume and complexity of a passage overwhelm the tube amps ability to adequately drive the sound, the clipping is not objectionable to the human ear. However when SS clips it is very objectionable. So even if the Manley were to be overwhelmed you may no be able to identify it.
Massive power supplies help. How much does the Manley weight vs the Cambridge?

Also, when you look at specs, you will see dynamic headroom. Some amps can put out peaks anywhere from 0db to 3db to 6db or more. What that means is that some amps rated at 32 watts will sound lousy as soon as they try to push 33 watts, while other amps with let's say 3db of dynamic headroom can handle 64 watt peaks without any noticeable loss of sound quality. Many times you are only playing at 5 watts but may need 10 times that for peaks in the music.
The thing I always go back to is what an "old timer" told me..... that unless there is lethal voltage under the hood, there wouldn't be music. Where do you get lethal voltage....tubes. O sure, I like some SS designs and sound, but tubes usually consistently sound musical. SS is hit and miss. The damping factor is so high with many SS designs they simply don't let the woofer move enough and put the brakes on before the harmonic structure has completely formed, giving a thumpy popping sound in the bass so all the notes sound the same. I don't call that music. However, there are some SS designs very musical like Pass, Bryston, Halcro, Levinson, Ayre, and others, but for the money, tubes gets it done. The key thing mentined before is the matching with your speakers, this includes the damping factor, efficency, etc. A 30wpc tube amp will not cut the job on Maggie 3.6 panels in a big room. You need some real horsepower say more than 500wpc. A speaker with a sensitivity of greater than 95 will do well with many amps at 20wpc or more. Trust your ears, and match amp with your speakers and enjoy the music. Speakers with a sensitivity of 100 plus dB will do well with half of a watt and 10wpc is overkill. It is also about the sensitivity.....Jallen
Well....I bought the Stingray II because Bobby suggested it as a great pick for my soon to arrive Merlin TSM-MXr's. Of course quite a few chimed in to say the Stingray/Merlin pairing was made in heaven, but I just did not expect the Stingray to sound so good with a pair of Def Tech speakers bought at Best Buy!

That's not a knock on the Def Tech BP7004's either. They're quite good, but were bought for home theater as the main course. The Stingray has them singing.

Bob