Ker pow!!!

[Marco]

I think it's one of those things where you wouldn't understand until you've lived with a system that sounds good at low volume. I have, and I remember being pleasantly surprised at the time.

As has been said earlier, you can have the volume down to whisper levels and everything sounds alive without loss of bite or bass.

...or moreover a convincing and accurate (if not as loud) portrayal of voices and instruments.

The key here is to successfully differentiate between what sounds 'correct', musically, but simply quieter, and similarly 'correct', musically, but simply louder. It's not about bass or treble, or anything like that. However, at least someone *gets* where I'm coming from!!

I'm not denying how, factually, the ear/brain relationship works [that's a different thing entirely], simply saying that not all equipment is equal, in terms of its ability to resolve low-level musical information, in such a way that the overall sound it produces is as good at low volumes, as it is when played more loudly.

However, Matt, you make it sound as if such a system is 'unusual' or outside of the norm, hence your "pleasantly surprised" remark. IMO, it shouldn't come as any surprise, if a) the constituent components of a system are of the requisite quality, b) they compliment each other well, and c) the system owner knows what he's doing!

For me, ALL systems should sound good at low volume. If not, something's not right. "Good", however, doesn't necessarily mean 'best'.

Marco.

[Marco]

Hi All,
In very basic terms:

Valves are high impedance voltage devices, Transistors are low impedance current devices, speakers are low impedance devices, valves therefore need some form of converting their high impedance to low, enough to drive a basic speaker impedance [ say 8 ohm] That’s where the output transformer comes in. Many would state that that is the main weak point of a basic valve amplifier, and to a point, I agree.

Now, if we look at Transistors, as stated, they are very low impedance compared with valves, and therefore an output transformer in most cases is not needed, [Mcintosh Amplifiers being amongst the few that still used output transformers in their solid state designs] Now it would seem from the examples given that transistors have the upper hand, however; this would only be true if the load they were driving remained constant.

Unfortunately that is far from the case where loudspeakers are concerned, i.e.; they may have a nominal impedance to start with, [4, 8, 16, etc] however; that can change quite dramatically once you put frequencies through them, and if we go back to the comparisons, when a speaker impedance falls [usually with low frequencies] the transistor output stage will put more power into the load, but as the speaker impedance rises, the power output will decrease, with a valve amp, with very minimal feedback, the opposite is the case.

Damping factor is another aspect of superiority grossly over played' by those promoting solid state designs over valve. Lets look at that for a moment, most well designed conventional valve amps manage a damping factor of around 12 to 20, now compare that to what a well designed conventional solid state amp is capable of i.e.; well into the hundreds, and again; those solid state fans amongst us here may be rubbing their hands with glee.

However, again’ all is not what it may seem, e.g., the full potential of that higher damping factor in solid state designs rarely gets put into play where loudspeakers are concerned, as most conventional speaker designs have a choke in line with the unit that would most benefit from it, the bass, or low frequency driver!

Anyway, I know there are many here knowledgeable enough to get where I am coming from on this, and can contribute their own thoughts, safe to say; there are good and bad aspects of both topologies, and because of this; there are very good, and very bad examples of both solid state, and valve designs.

Excellent post, Anthony, expressed in a way that was fairly easily understood by a layman.

I would also add that the 'problems' associated with valve amps, in terms of reproducing bass frequencies, are only (in the real world) applicable when using the wrong speakers. Use the right ones (easy load, high-efficiency), and it's simply a non-issue, if the valve amp in question has been properly designed.

Therefore, as ever, as you've ably highlighted above, in your outlining of the various pros and cons of valves and transistors, it's simply a question of context.

Could I ask you which part of what you wrote, if any, might help explain what was mentioned earlier, and what is commonly heard by almost everyone who's carried out the (listening) test, in that 'valve watts' subjectively seem more 'potent', or powerful, than those of their solid-state counterparts?

I'm specifically interested in your mentioning earlier of voltage rails.

In essence, what's your theory behind why that's the perception of so many? IMHO, there has to be some credible technical explanation for it, because I don't believe that the effect is being imagined

Marco.

[walpurgis]

I don't believe anybody has mentioned that many horn speakers seem to retain correct proportions of dynamics and presence at more or less any volume setting. So perhaps there's more to it than amplification characteristics.

[Marco]

Yup, that's another valid point in this discussion, Geoff, and one we so far haven't explored

Marco.

[anthonyTD]

Hi Marco,
From my own perspective, and experiences;
As stated earlier; Some reasons for the way Valve amplifiers sonicaly seem to be more potent watt for watt compared to solid state are; Minimal use of over-all feedback, and thus the way they seem to be able to follow the varying impedances of the loudspeaker, Also; the higher voltage rails they run on also play a part. Over the years I have been on AOS I have discussed the diffrences between Valve and solid state, many times, and I could resurect some of those posts if there is any more interest in the subject.

Excellent post, Anthony, expressed in a way that was fairly easily understood by a layman.

Could I ask you which part of the above, if any, might help explain what was mentioned earlier, and what is commonly heard by almost everyone who's carried out the (listening) test, in that 'valve watts' subjectively seem more 'potent', or powerful, than those of their solid-state counterparts?

In essence, what's your theory behind why that's the perception of so many? IMHO, there has to be some credible technical explanation for it, because I don't believe that the effect is being imagined

Marco.

[anthonyTD]

I don't believe anybody has mentioned that many horn speakers seem to retain correct proportions of dynamics and presence at more or less any volume setting. So perhaps there's more to it than amplification characteristics.

[Marco]

Hi Marco,
From my own perspective, and experiences;
As stated earlier; Some reasons for the way Valve amplifiers sonicaly seem to be more potent watt for watt compared to solid state are; Minimal use of over-all feedback, and thus the way they seem to be able to follow the varying impedances of the loudspeaker, Also; the higher voltage rails they run on also play a part. Over the years I have been on AOS I have discussed the diffrences between Valve and solid state, many times, and I could resurect some of those posts if there is any more interest in the subject.

Thanks, that makes sense to me. However, could you expand more on the bit I've highlighted, as to my knowledge, no-one so far has suggested that as a possible cause

Play a part in what way?

Marco.

[Shovel_Knight]

Maybe I’m missing something, but amplifiers using the same topology will be similar to each other. In some extreme cases, you have just a couple of valves and a handful of passive components per channel. If you replace those passive components with unobtanium resistors and magic dust capacitors, you will not suddenly get a new and vastly superior amplifier design. And as I mentioned already, nothing stops you from using the same exotic passive components in a solid state design.

And no matter how good your coupling capacitors and output transformers are, they will always be worse than no coupling capacitors and no output transformers

But then again this topic has been debated ad nauseam and both valve and solid state amps will always have their proponents.

What I personally don’t like about tube amplifiers is that to get them to really sing, you have to use them with certain speakers and even listen to certain kinds of music. This seems a bit limiting to me.

I like valves in OTL configuration and in fact I used to own an OTL tube headphone amp which I really liked, but then again it was only suitable for high impedance headphones.

[Macca]

What I personally don’t like about tube amplifiers is that to get them to really sing, you have to use them with certain speakers and even listen to certain kinds of music. This seems a bit limiting to me.

Only true of some valve amps, well quite a lot of them actually but it doesn't have to be the case. The main problem is that to build a valve amp that works properly is expensive. Then stick on manufacturer profit, distributor and dealer margins and your at £10K before you've said tube rolling.

So there are a lot of cheap, compromised valve amps around giving the whole lot a bad name, unless, as you say, you are careful what music you play through them. I have heard a few shockers, looked great, lovely casework, sound absolutely terrible, and the owners were in complete denial about it.

[anthonyTD]

If the quote below was truly the case, I would have given up on Valve amplifiers years ago!

What I personally don’t like about tube amplifiers is that to get them to really sing, you have to use them with certain speakers and even listen to certain kinds of music. This seems a bit limiting to me.