Alexander Dumble on YouTube?

[nickt]

[gearhead]

The speed of the effect of electricity is very fast. However, the actual speed of any single, particular electron in a copper wire is nowhere near the speed of light.

http://hyperphysics.phy-astr.gsu.edu/hb ... hmmic.html

It's in centimeters per second, depending upon conditions; called the Drift Speed. I had totally forgotten this effect myself until digging into amps the last couple years.

Honestly, I am skeptical of many audio claims for the purpose of product sales such as Monster. On the other hand, amp gurus know how to build amps based on certain things they feel strongly about. I gotta go with their instincts until proven otherwise by double-blind Audio tests. The human ear is a truly remarkable sensor.

Dave E. too. (BSEE 1982-VA Tech)

[Pete]

The fundamental reason that tube amps are so much more pleasing to the ear than transistor amps is this: When tubes are driven to distortion, they tend to add even harmonics--especially the second harmonic. When transistors are driven beyond their linear region of operation they clip sharply--which adds odd harmonics (the spectrum of a square wave consists of odd harmonics).

So, how 'bout when the amp is NOT "driven to distortion? Does the tube amp still sound better than the transistor amp? I know some would say yes. I feel I'm not alone in thinking tube amps in very clean mode, sound better than transistor (especially dumble). I prefer the "D" amp and I play clean more than 50% of the time.

[dre95060]

The THD of a tube guitar amp is still quite high (5% or more) even when it is running "clean". So the sound is going to be colored anyway. And there are other components that affect the tone of a tube amp--such as the output transformer--that are not present in a solid-state amp. If you play your guitar through a tube amp designed for hi-fi audio (very low THD) it will not sound very good.

The best amp builders excel because they treat the guitar-amp combination like a musical instrument--which it is--rather than a circuit. They know there are many variables that affect tone even between two amps built to the same schematic. And they have developed techniques to voice the amps and get the sound they want.

I am not arguing with the obvious success of designs from guys like Dumble and Fischer. However, they are obviously not physicists. Neither was Stradivarius, for that matter. Just because you build an amp to a Dumble schematic doesn't necessarily mean that it is going to sound like a Dumble amp--as I am sure many of you know from personal experience.

Regards,

Dave E

[dre95060]

The speed of the effect of electricity is very fast. However, the actual speed of any single, particular electron in a copper wire is nowhere near the speed of light.

http://hyperphysics.phy-astr.gsu.edu/hb ... hmmic.html

It's in centimeters per second, depending upon conditions; called the Drift Speed. I had totally forgotten this effect myself until digging into amps the last couple years.

Honestly, I am skeptical of many audio claims for the purpose of product sales such as Monster. On the other hand, amp gurus know how to build amps based on certain things they feel strongly about. I gotta go with their instincts until proven otherwise by double-blind Audio tests. The human ear is a truly remarkable sensor.

Dave E. too. (BSEE 1982-VA Tech)

Yes, this is absolutely correct. But it is the speed of the electromagnetic waves we are concerned about. This is the "information" in the signal path. I think all this talk about electrons is leading people astray--Howard Dumble included. We have an advantage as engineers because we had Maxwell's equations pounded into our brains.

Let me try this for a lay analogy: Suppose Helen Keller is standing in water at the shallow end of a swimming pool and Howard Dumble does a cannon ball at the other end. In a few seconds, Helen knows that somebody is in the pool even though any given water molecule has not moved towards her very much. She is hit with the wave!

This reminds me of Einstein's explanation of how radio works: "You see, wire telegraph is a kind of a very, very long cat. You pull his tail in New York and his head is meowing in Los Angeles. Do you understand this? And radio operates exactly the same way: you send signals here, they receive them there. The only difference is that there is no cat."

Regards,

Dave E.

[gearhead]

Yeah, I actually need to amplify (pun intended) on my comments.

The amp gurus, thru extensive experience, know that doing X with Y component results in very good tone Z. Now, what they attribute that too is sometimes not as solid. Ken's statement about color of wire in that interview took me aback, but he never said it always HAD to be that color. My (admittedly liberal) interpretation is that he needed to use wire from the red spool to get the results he wanted.

Skin effects? Maybe not, but you gotta wonder whether transmission of an electromagnetic signal thru a wire with two different metals might not cause some perceptible audio effect. Copper and silver have different conductance properties. PTFE is a better insulator than PVC.

All that said, they aren't physicists, but artists of a different sort.

[Tubetwang]

All that said, they aren't physicists, but artists of a different sort.[/quote]

They may be Comedians also...pulling on our legs...for all we know...

You've got to have a laugh sometimes...

[The Tube Doctor]

Whenever I read about some of the "Science" that's used to explain various phenomena, I find myself remembering notable quotations from
luminaries such as the late Dr. Richard Heyser;

"One of the most belittling experiences is to deride the 'Black Art' of a craftsman who gets consistent results by a certain ritual which he cannot explain, and then to discover that his actions in fact, held a deeper technical significance than we understood from our simplified model."

And this one, by the late Dr. Micheal Polanyi;

"It is pathetic to watch the endless efforts- equipped with microscopy and chemistry, with mathematics and electronics- to reproduce a single violin of the kind that a half-literate Stradivari turned out as a matter of routine more than 200 years ago."

So, when some inexplicable phenomenon rears its head, and my education and experience fail to provide me with a quantifiable answer, I just reflect on how much there is that we don't know, about the things with which we're familiar.

Silver wire? Cable dress? Shielding termination? Use the mind, as far as you're able, but trust the ears. They don't seem to suffer the confusion of the mind.

[ampdork]

Those are two of the coolest quotes I have ever read outside of some of Telsa writings and "There are no electrons". Thanks for sharing.

[talbany]

This reminds me of the same type of hype associated with class A amps. Just because it is Cathode bias doesn't mean it is Class A. as you all know

[Structo]

Great Quotes!

[Normster]

Silver wire? Cable dress? Shielding termination? Use the mind, as far as you're able, but trust the ears. They don't seem to suffer the confusion of the mind.

Actually, I liked this "quote" best.

[benoit]

This reminds me of the same type of hype associated with class A amps. Just because it is Cathode bias doesn't mean it is Class A. as you all know

Not to mention class A operation (in and of itself) never stopped an amp from sounding awful.