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Interesting discussion here that some of you Amp freaks might be interested in. It's with Ian from Blackstar, so I'd like to keep any discussion solely on your thoughts on the different tech involved and not so much dissing this or that manufacturer. There should be something in here for everyone. I think it's going to be a 5 part series with different people from Blackstar.

 

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I found it very interesting. It didn’t change my mind about anything but it did put to words much of what has been in my head but I was never able to put to words. I quite liked at the end when they talked about leads affecting your tone and he reached over and turned up the treble and said there now my lead sounds the same as yours. It doesn’t matter what gear I use it always needs some adjustment for the environment I’m using it in. I also liked the way they explained why handwired sounds different from pcb.
 

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If it were people from more than one company I may have actually watched it.

My not clicking on YT streak continues.
Even as a Blackstar owner, I had second thoughts about watching it. Figured it was just going to be a commercial for their new product(s). Came across as being fairly unbiased....key word fairly because some of the topics were touched on in a Blackstar way of thinking. Which might be what is being aimed at. Not their thinking in particular, but the way people in general view the differences and what they deem to be necessary to their sound.
 

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Exactly. It’s such a ridiculous fucking statement that nobody is suggesting I moved on.
 

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Will this clear things up? I'm pretty sure the BS guy brought this up at some point.

A class-D amplifier or switching amplifier is an electronic amplifier in which the amplifying devices (transistors, usually MOSFETs) operate as electronic switches, and not as linear gain devices as in other amplifiers. They are rapidly switching back and forth between the supply rails, being fed by a modulator using pulse width, pulse density, or related techniques to encode the audio input into a pulse train. The audio escapes through a simple low-pass filter into the loudspeaker. The high-frequency pulses, which can be as high as 6 MHz, are blocked. Since the pairs of output transistors are never conducting at the same time, there is no other path for current flow apart from the low-pass filter/loudspeaker. For this reason, efficiency can exceed 90%.
The term "class D" is sometimes misunderstood as meaning a "digital" amplifier. While some class-Damps may indeed be controlled by digital circuits or include digital signal processing devices, the power stage deals with voltage and current as a function of non-quantized time.
Class-D amplifier - Wikipedia
 

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The only people who believe tube amps sound better than solid state are those who are paying way too much for booteek crap.
 

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The only people who believe tube amps sound better than solid state are those who are paying way too much for booteek crap.
I guess it depends on the sound you're looking for. Some great solid state amps out there but I have yet to find one that responds to my playing the way a good tube amp does.
 

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I haven’t heard a SS or modeller that will raise the hair on the back of my neck like a proper tube amp. I still haven’t heard a Kemper or Helix though. I think as players migrate from gigging to home playing (it’s the future) the majority will move to modelling. Doesn’t mean I like it.
 
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"At its most fundamental level, this is because a moderately overdriven valve amp produces strong even harmonics, which add a sweetening complexity to a sound. An overdriven transistor amp, on the other hand creates strong odd harmonics, which can cause dissonance."


Physics explains why rock musicians prefer valve amps

February 8, 2017, Institute of Physics
For many guitarists, the rich, warm sound of an overdriven valve amp – think AC/DC's crunchy Marshall rhythm tones or Carlos Santana's singing Mesa Boogie-fuelled leads – can't be beaten.

But why is the valve sound so sought after? David Keeports, a physics professor from Mills College in California, looked at the science of valve amps for the journal Physics Education, to explain why their sound is 'better' to the ears of so many guitarists.

Professor Keeports said: "Although solid state diodes and transistors are cheaper, more practical, and technologically more advanced than glass valves, valves survive because so many guitarists are exacting about their tone, and prefer the sound a valve amp gives them."

"At its most fundamental level, this is because a moderately overdriven valve amp produces strong even harmonics, which add a sweetening complexity to a sound. An overdriven transistor amp, on the other hand creates strong odd harmonics, which can cause dissonance."

Professor Keeports explored the physics of why even harmonics enrich a sound, and why the timbre of the sound from a valve amp changes when a guitar is played more loudly.

First he ran a 200Hz sine wave – a pure wave with a single frequency– through a small Bugera hybrid amplifier, featuring a valve preamp and a solid state power amp. He tested both 'sides' of the amp; first turning up the gain knob, which controls the valve preamp while the master volume knob (controlling the solid state power amp) was set low. He then repeated the process with the preamp set low and the master turned up.

Using Logic Pro X music production software, he examined the resulting sound waves in both frequency and time domains.

Professor Keeports said: "The output from the amp showed that a moderately overdriven valve preamp produced prominent 2nd and 4th harmonics at 400 and 800 Hz, and only a very weak 3rd harmonic at 600 Hz. For the solid state power amp, this pattern was reversed. All of this behavior is consistent with the common claim about the harmonics that valve and solid state amplifiers produce. But the story is not quite so simple. Overdriving the valve preamp harder produces strong odd harmonics."

"The shift toward odd harmonics at increasing gain is a characteristic of valve amplifiers that further explains their appeal. An electric guitar player can overdrive an amp two ways: by turning up the amp's gain control, and by attacking guitar strings more strongly. Experienced guitarists don't just play their guitar – they also play the amplifier. By striking the strings harder or softer, they can change timbre along with volume."

And why does a valve amplifier behave this way?

"The simple physics of triode valve function explains everything," said Professor Keeports. "Valves have two ways to to flatten a sine wave. Overdrive a valve moderately, and it flattens just the top of the wave to make an asymmetric wave that is rich in even harmonics. Overdrive the valve harder, and it also flattens the bottom of the wave to produce a symmetric wave full of odd harmonics."

"The even harmonics provides the complex, warm, rich sound that so many guitarists desire. Add to that a valve amp's ability to produce somewhat dissonant yet driving sounds when a guitarist attacks strings harder and turns rhythm playing into lead playing, and valve function creates just the harmonics a rock guitarist needs."



Read more at: https://phys.org/news/2017-02-physics-musicians-valve-amps.html#jCp
 
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