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If tubes amplifiers measure poorly, why are they perceived as sounding better?

dalbert02

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From a casual observation tube equipment measures poorly compared to solid state. However, many people say tubes sound better. How is this possible? From personal experience, I have noticed some poorly measuring tube amps will raise the hairs on the back of my neck while listening to Sade. It is as if she were breathing on my neck and ears. However, I have also noticed I do not get this same physical reaction with some very well-measuring solid-state amplifiers. The scientific part of me says this is bullshit but my physical response is undeniable. How can I get these two sides of my brain to agree? I want to believe if it can't be measured it does not exist yet the goosebumps on my neck do not lie. Has anyone else had this experience?
 
From a casual observation tube equipment measures poorly compared to solid state. However, many people say tubes sound better. How is this possible? From personal experience, I have noticed some poorly measuring tube amps will raise the hairs on the back of my neck while listening to Sade. It is as if she were breathing on my neck and ears. However, I have also noticed I do not get this same physical reaction with some very well-measuring solid-state amplifiers. The scientific part of me says this is bullshit but my physical response is undeniable. How can I get these two sides of my brain to agree? I want to believe if it can't be measured it does not exist yet the goosebumps on my neck do not lie. Has anyone else had this experience?
You have actually answered yourself. Tube amplifiers have a specific sound and are not neutral. If you like this sound then OK. But first of all, it is not the sound that was recorded in the studio. Secondly, you won't like the tube sound on some recordings. And you have records that sound nice on tubes and records that can't be listened to on them.
I catch myself that sometimes I like to listen to music (selected recordings) on one of my AB class amplifiers, which has a transformer at the input. Evidently, I like the distortion resulting from saturation and hysteresis. That's how euphony works.
But when it comes to serious listening I try to use “transparent” amplifiers - not bringing any sound. And usually on these amps I don't have the problem that some recordings sound cool and others are impossible to listen to.
 
You can create similar effects on female singers with an Exciter. A good example is Eva Cassidy's live album. That does not mean that one should use an Exciter for all types of music.
What do you mean by ‘exciter’?
 
How can I get these two sides of my brain to agree? I want to believe if it can't be measured it does not exist yet the goosebumps on my neck do not lie. Has anyone else had this experience?
Either measurement is wrong/incomplete or you have a mental/physical condition. If I had the money to spend, only thing from getting a fully tubed setup would be inconvenience for changing and biasing tubes. Ask yourself: how can a $300 record player and a stock riaa give you full sound when it measures stupidly bad in relation to 110db + SNR equipment? Self suggestion :D No way man. If it sounds good to you, go for it!
 
It’s called euphonic.

Running an electric guitar through a Marshall stack sounds way cooler than through a ultra clean preamp and high end studio monitors.

Distortion can sound quite pleasant with the right source and the right audio source.

That, though, is not high fidelity. It’s a sound effect.

As an engineer, I’ve had occasion where adding a good bit of band-limited distortion added clarity to my bass in a mix. Played solo, it sounded cool, but quite different from the perception when in the full mix. Adding distortion made it sound “cleaner”. Yes, very odd.

Doing the same thing to the entire mix would have sounded horrible.

If you’re not plugging a Les Paul or a Strat into it, avoid tubes… and vinyl… and 8-tracks… and video tape, etc. It’s obsolete tech which has no path forward.
 
I want to believe if it can't be measured it does not exist yet the goosebumps on my neck do not lie.

My opinion is that you are looking at the wrong measurements. Look for measurements of perceptual bias.
I bet that if you switched blind between the valve and solid state amps, the differences would pretty much disappear.

Depending of course on the valve amp and speakers you have, I reckon in many cases the differences in amp measurements look *much* bigger than they actually sound
 
Many (most?) valve/tube amps suffer high output impedance due to the output transformer. As no passive speaker system has a ruler-flat impedance curve, the amp tracks the impedance curve and equalises the speaker to a small but highly audible degree. Add some nice ringing in the valves to give a kind of sexy 'halo' over the sound and there ya go...
 
What do you mean by ‘exciter’?
An exciter is an audio effect that creates distortion only on the higher frequencies via a highpass, which is then mixed with the original signal at low (adjustable) level. That way you get controllable harmonic overtones which are perceived as "airy", "rich" and "spacious". Very common in music production and live concerts.
 
As an engineer, I’ve had occasion where adding a good bit of band-limited distortion added clarity to my bass in a mix. Played solo, it sounded cool, but quite different from the perception when in the full mix. Adding distortion made it sound “cleaner”. Yes, very odd.
Our brains can extrapolate tones from overtones. Maybe that's what's happening there? You enhance the overtones of a bass, which tricks our ears into being able to "hear" the actual bass better than before. It isn't cleaner in technical terms, but more clearly audible for us.
 
As others have said, on certain audio in certain amounts, distortion sounds really good. In the studio, it would not be uncommon to find that some amount of harmonic distortion was added to every single track on a recording, because it sounds better with distortion.

The thing is, more is not necessarily more when it comes to "nice' distortion.

- in the studio, they've already added as much distortion as they think the recording needs.

-in the studio, they add the right kind and amount of distortion to each individual instrument and voice.

A low fidelity tube amp just adds its own dose of distortion to everything indiscriminately.

So, adding even more distortion on playback is like salting the food without tasting it. Maybe you really love salt, fine, but it is not what the chef intended.
 
Our brains can extrapolate tones from overtones. Maybe that's what's happening there? You enhance the overtones of a bass, which tricks our ears into being able to "hear" the actual bass better than before. It isn't cleaner in technical terms, but more clearly audible for us
Kinda. It wasn’t just that the overtones were taken up in level, but that the distortion added new harmonics that didn’t exist from about 150 to 600Hz. The two octaves in that range each had their own bands of distortion.

I was playing a 5 string fretless semi-acoustic bass with classical style strings (tape wrapped). It sounded beautiful, but the song got dense with guitar and strings and the second and third harmonics of the bass were getting lost. EQ wouldn’t fix it at all and multiband compression was marginal.

Adding distortion took the small things like clicks when strings were pressed against the fingerboard and the 3rd & 5th harmonics and made them more prominent without screwing up the instrument’s timbre. All of those obscured elements that made the bass sound so wonderful were audible again.

Hey, I love playing my bass with a ton of effects. Filters, distortion, synths, pitch shifters and every type of time and modulation effect are my thing.

When it comes to monitoring my music, though, I want a straight wire with gain. That exists now.
 
What do you mean by ‘exciter’?

An exciter can be a hardware component or a piece of software (like a software plugin you might use with an audio editing and processing app).

Either way, they generally work by adding harmonics to the signal, usually 2nd harmonics - so for example they will synthesize an 8kHz harmonic of a 4kHz sound that's in the music.

This tends to increase the feeling of "fullness" or ambience. It's also by definition distortion. But the thinking goes that since it's only the relatively pleasing 2nd harmonic and it's added in a controlled manner that you can adjust and dial in to preference, it makes the sound "thicker," and adds an extra "sparkle" in the treble (since the added harmonics in that range are likely to be pretty audible) - therefore it makes the sound more "exciting."

Not to mention, if you add a bunch of 2nd harmonics to the signal and don't adjust the gain to compensate, the result is going to be a little louder than the original, and often we perceive a slightly louder signal as sounding better and... more exciting.
 
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An exciter can be a hardware component or a piece of software (like a software plugin you might use with an audio editing and processing app).

Just to name a few that I use and recommend too:

- Fabfilter Saturn 2
- IK Multimedia Saturator X
- Ozone 11 Exciter
- Waves Magma BB Tubes
- the brand new Fabfilter Pro-Q 4 EQ (that I currently use for crossover duties) has a new, very simple Clean-Subtle-Warm switch that is worth trying too
 
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