Excuse my innocence,but what is this LED business everyone is mentioning? Is it cathode bias, as a quiet voltage ref. or is it merely cosmetic, e.g. wiring up a magic eye tube to wink in time with the music?
I might reference the above (somewhere) placebo comment. The music we hear is largely a complex interpolation by our brains. The amount of processing inside your cranium is astounding, so what is happening is that your brain conveniently recreates the live "feeling" when given the appropriate cues from a recording that contains them. Placebo, live!
This is also why, up to a point, distortion and less than perfect sound quality is ok. We make up for it.
Just a local Neurologist's point of view...
Piano3,
It is when for cosmetic reasons people light up the tubes with LED's.
They look "nice" to some people! If it works for them then great.
Regards
M. Gregg
It is when for cosmetic reasons people light up the tubes with LED's.
They look "nice" to some people! If it works for them then great.
Regards
M. Gregg
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I am quite sure that this is so; particularly as I have experience of live performance from both sides of the fence. If I hear playback,at least the first time, I am almost back there doing it, with all the nerves etc. ....
I'm not sure ow it relate to placebo; warts==live cues. Often, studio recordings have had the warts surgically removed, and then had fake skin airbrushed over the wounds. It's not often a very convincing result. Add to that the compression and you have sonic mush.
A live recording by contrast contains all the cues necessary for the brain to complete the picture. As long as the job was done in a well balanced high-fi way, the result is a far more enjoyable recording than any frankenstein-like multi-layer glued together autotuned beat-aligned squish-squashed studio monster...
Realism IMO has very little to do with absolute linearity;
Air distorts sound. The speed of the compression part of the wave is greater than the rarefaction part of the wave. This causes 2f distortion. The ear also adds low harmonic distortion to things. Both these effects are greater at high volume levels. Musical instruments and the human voice contain abundant 2f and 3f partials. These are not == distortion but 2f and 3f distortion sometimes hides behind these partials. Convenient, eh? Any distortion that doesn't resemble natural partials sticks out like a sore thumb.
Tube amps, when they do distort, do things that resemble air, ears, and musical instruments, and do this more so at higher signal levels (volume levels).
Maybe more importantly, well designed tube amps avoid doing things that don't resemble music, air, and ears. Well designed solid state circuits can do this also, at least as well in my recent experience using SS devices in a tube circuit.
Cheers
Harmonics (or overtones, not quite the same thing) from the instrument, echoes from the hall, playing techniques etc. are not distortion but part of the signal. Some may be more pleasant than others, which is an artistic decision made by the musicians and others. Distant drilling, underground trains, noisy audiences etc. are on the borderline - you could argue that as they may be part of the live experience then they too are not distortion, but I prefer my music without these additions!
Havng captured the signal at the microphones (generally the fewer the better, in my opinion) the aim then should be to get it as unmolested as possible to the loudspeakers. This is, or was, the aim of hi-fi. I know transducers are horrible non-linear things with lumpy frequency responses and resonances but we have to do the best we can. Anything between the transducers should only distort the signal in an attempt to undo transducer damage. It should not add any more "musicality", "warmth", "slam" etc. etc. If you don't like the performance, choose a different performance!
I know at the end of the day recorded music is just an illusion, but I think we have to let the musicians decide what illusion they wish us to hear. Otherwise it would be like viewing a painting, but with knobs to twiddle the exact colours to our own preference instead of simply enjoying whatever Van Gogh or Turner put on the canvas.
Havng captured the signal at the microphones (generally the fewer the better, in my opinion) the aim then should be to get it as unmolested as possible to the loudspeakers. This is, or was, the aim of hi-fi. I know transducers are horrible non-linear things with lumpy frequency responses and resonances but we have to do the best we can. Anything between the transducers should only distort the signal in an attempt to undo transducer damage. It should not add any more "musicality", "warmth", "slam" etc. etc. If you don't like the performance, choose a different performance!
I know at the end of the day recorded music is just an illusion, but I think we have to let the musicians decide what illusion they wish us to hear. Otherwise it would be like viewing a painting, but with knobs to twiddle the exact colours to our own preference instead of simply enjoying whatever Van Gogh or Turner put on the canvas.
I enjoy your laconic posts almost as much as your generously detailed ones!
I find it strange how widespread this distortion atitude is. Some months ago I attended a tutorial on semiconductors as part of an introductory quantum mechanics course. This same matter came up of tubes being used to produce pleasing distortion. Most improbably, there was amongst the few students who turned up one who played the guitar and he was most voluble on the subject. I felt obliged to point out that in general the transfer function of tubes was much more linear. The tutor, a mathematical physicist working in the defence industry, looked surprised for a moment before conceeding that this was so but qualified this by saying that there were far more linear semiconductors available than those used in normal civilian applications. My lack of knowledge on this prevented the discussion from going any further unfortunately.
Just for interest,
Its interesting how different semiconductors "sound different" in the same circuit.
Its interesting how different tubes sound different in the same circuit, however the electrons are leaving the cathode going to the anode via grids. internals of the tube are dare I say similar! Even the same tube type can make the sound different!
Ups sorry
Regards
M. Gregg
Its interesting how different semiconductors "sound different" in the same circuit.
Its interesting how different tubes sound different in the same circuit, however the electrons are leaving the cathode going to the anode via grids. internals of the tube are dare I say similar! Even the same tube type can make the sound different!
Ups sorry
Regards
M. Gregg
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So I guess we are tweaking the painting. LOL
So how HIFI is a HIFI after repair, mod, tweak!
Regards
M. Gregg
So how HIFI is a HIFI after repair, mod, tweak!
Regards
M. Gregg
Most probably, while making devices for civilians from semi-conductors, they use full-bodied-conductors for military. 😀
...much warmer than the semi-conductor. 😉
An externally hosted image should be here but it was not working when we last tested it.
The keyword is, smoothness
Can you imagine this full-bodied-conductor made of rough absolute linearly square chunks aligned such a way they form a perfectly straight line?
It will look and measure very linear. But try to scale down and see fine details... You will definitely see tiny higher order harmonics introduced as an attempt to make it linear. Very linear according to measurements. Now, pretend as if this tiny roughness is below "noise floor", or below "audibility threshold", and you are happy manufacturer of cheaper in production gear made of modern components.
I'm not sure, but looking at the packaging (TO44XL), I have a feeling that he may sound a little woolly.
I'm talking about guitar here, not HiFi. 99.9% of all electric guitar u hear is using PP amps, and when they crank them up so the output stage saturates, it's mainly odd, and very sweet odd as well. I like SE guitar amps and their mainly even order harmonics, but most guitarists find it a bit muddy.
Btw, 'harmonics' for us engineers is not the same for musicians.
Sure they are. Not all musicians realize it, but many do understand the importance of harmonic content in individual notes. Some simply refer to it as "tone." Either way a [guitar, violin, cello, voice] wouldn't sound good if it just produced a sine wave, although the near ubiquity of Auto-Tune in modern music might suggest otherwise.
Musicians might not be designing circuits to minimize THD, but anyone with a good ear understands the importance of harmonic content.
W/RT under-voltage tubes, I will vouch for the ability of a preamp with one or two 12AU7 tubes (common cathode stages) running at 12VDC to turn flat-sounding solid state amplifier into the next best thing to a Mesa Boogie or Plexi [or insert your all-tube amp of choice here]. All for a ridiculously low cost. If you aren't looking to introduce distortion, however, I would stay away.
No need for an electric guitar. As Michael Koster already explained, any media, including air that transfers sound, surfaces that reflect it, are non-linear and distort sound. But their non-linearity is smooth. That means, the softer is the sound the less it is distorted. The similar smoothness of transfer curve has a tube stage. It does not kill details, but introduces own distortions. Such distortions are dramatically less audible than distortions of stages that use sharp exponential devices linearized by feedback. The result of straightening of curves of exponential devices may be more linear if to measure the whole big curve, but in order to get is straighter it is bent much more sharply than tube, air, ear, wall curves, all of which are not so straight if to measure on the whole length.
I.e. in order to not introduce audible distortions we go wrong way making transfer curves straighter, while we should make them smoother. How? Selecting proper devices, topologies, regimes, that introduce less distortions. Such a way getting alterations similar to what we expect from air, ear, wall, we avoid alterations that human perception does not treat as alien.
It is all about priorities: smoothness VS straightness. You can drink a water with lots of mineral salts that don't add own taste. But you can choose to purify the water and remove that salts using some bitter substance that neutralizes salts, but adds bitter taste, even when percentage of such a cleaner is hundred thousand percent less than was of tasteless mineral salts the water contained originally.
Clean tube sound does not add "sweet distortions". What it does really, it amplifies the sound without adding bitter distortions that sound nasty, even when their percentage is very low.
You choice: either perception, or percentage...
Interesting and helpful perspective Wavebourn. I have to pay very close attention when reading your posts as your writing style is quite unique but that really does help me to focus. 🙂
I have often pondered this whole subject of what makes music sound real. I have had this nagging feeling that when we try to beat the equipment into submission using things like heavy handed FB to make up for either poor device transfer function or bad design that some violence that is hard to define or measure might be occurring. Had not not previously thought of it as bending the curves as you state but that does make for a great mental picture worth pondering.
Similarly when we take inefficient transducers and throw gobs of power at them to beat them into submission I think that some of the life seems to be kicked out of the music too. Subtle maybe but there. Of course there are some situations where brute force is really the only practical tool available like when size requirements trump all else but when we have the luxury to do so it seems beneficial to use more natural approaches.
You water analogy is fantastic.
Sorry for rambling but it is a very complex subject no?
I have often pondered this whole subject of what makes music sound real. I have had this nagging feeling that when we try to beat the equipment into submission using things like heavy handed FB to make up for either poor device transfer function or bad design that some violence that is hard to define or measure might be occurring. Had not not previously thought of it as bending the curves as you state but that does make for a great mental picture worth pondering.
Similarly when we take inefficient transducers and throw gobs of power at them to beat them into submission I think that some of the life seems to be kicked out of the music too. Subtle maybe but there. Of course there are some situations where brute force is really the only practical tool available like when size requirements trump all else but when we have the luxury to do so it seems beneficial to use more natural approaches.
You water analogy is fantastic.
Sorry for rambling but it is a very complex subject no?
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