Tube amps...why?

Boogie

Zombie Two, DFZ
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Here’s the most - as Mick puts it - simple and eloquent explanation of why a valve/tube amp does what it does to a guitar signal. Skip to 11:07 for the summary, but his guy is chock full of great nerdy details.


Brilliant!
 
Here’s the most - as Mick puts it - simple and eloquent explanation of why a valve/tube amp does what it does to a guitar signal. Skip to 11:07 for the summary, but his guy is chock full of great nerdy details.


Brilliant!

I was thinking of posting this to illustrate the use of the Tone and Volume controls and why they are a very useful tool for a guitarist. So many roll there tone and volume right up to max, set their gear based on that and only use their volume as a 'mute' switch.

Of course its still interesting around the use of Valve amps too but I do think there is a LOT more to learn than just what a Valve amp does.
 
I listened to that yesterday, was interested by the capacitors variance. It was a tad dry though overall.
 
As a synthesist, it’s interesting how much of this explanation dovetails with the creation of sounds on a synthesizer. You have a waveform that in its simplest form is an oscillator (think of the oscillations on a guitar string, for example) that feeds filters, modulators, and other modifiers, the most important of which is the filter that adds a resonant peak where you decide to put it, and thereby generates overtones for the oscillator, plus LFOs, ADSR envelopes to control attacks sustain, decay and release, etc.

He’s right when he says that the basic oscillator - the string - isn’t very complex (though in my opinion the wood and metal choices and pickup act as modifiers to the oscillating tone of the string, as the wooden parts do on an acoustic guitar, where the hollow guitar body is a big acoustic resonant filter). But the main thing that affects what we think of as electric guitar tone is the amp.

I’ve said this before, but a what we’d call a clean tube amp generates harmonics even when it’s not clipping. These old circuits cruise at 10-20% harmonic distortion, meaning they’re adding harmonics to the sound coming into the amp, and creating that familiar tone. It’s a tone that’s inherently more complex than it would be without the harmonic distortion that the circuit adds, even clean.

Increase the gain into the circuit, and it gradually starts to break up as it delivers more harmonic distortion, compression, and saturation.

Regardless of where you come down on the tubes vs modelers question - my view that yes, you can model distortion, but not in the same way, being infamous around here - you have to admire the devices that make the electric guitar so endlessly fascinating, regardless of how they operate on the signal to make the sound.
 
So, I found this interesting, and then I also saw this video, too. Skip to 13:25 for the question about the future of Fender's "modeling". It'd be interesting to see how they would actually get there.

 
So, I found this interesting, and then I also saw this video, too. Skip to 13:25 for the question about the future of Fender's "modeling". It'd be interesting to see how they would actually get there.


Part of that discussion makes me want to stock up on NOS (and other) tubes. I love my tube amps, I don’t want anything else, but if they stop making tubes elsewhere, then we have a different ballgame that I personally don’t want to play.

To be honest, I hope that day never comes, but this is equivalent to my “end of the world” scenario, where I have a lifetime supply of NOS (and other decent new stuff, if it exists) tubes ready to go. Fortunately, I’m old enough that “lifetime supply” isn’t 10 sets for each amp. Let’s see...if I retube every couple of years, and my life expectancy is...

Oh never mind. Just get more effing tubes, Les!!

I’ve got enough NOS to retube my HXDA twice, and my DG30 once; I’ve also got spares for the Lone Star, but not enough to completely retube. The Fillmore is a brand-new project for me, and I haven’t tried NOS in it yet. But I just bought an RCA 12AX7A, and some NOS GE JAN 12AX7WAs to get started on that project.

However, it’s quite clear that I NEED MORE NOS TUBES and I’m in full panic mode!!!!

I’ve really got to work harder so that I can afford all this stuff. ;)
 
Looking forward to watching this next week when I've got some time. AKA, when I'm at work!
 
I love tube amps, but I don't own any, as it just doesn't make sense for me personally. I'd hate to see them die
simply because tube manufacturing stops.

It'd be awesome if they could find a better way to make tubes that didn't cause so many environmental issues.
Sometimes it's hard to believe with the technological advances we've made that we can't get there.
 
I remember in the ' 90s when tubes got scarce. Market demand caused a few tube plants to open or expand.

If there is sufficient demand, tubes will get made one way or another. If not, they won't.

I once got to try a couple prototype 12AX7 tubes that had solid state circuits inside. AT&T I think had commissioned them. This is a possible way to go as well.
 
I remember in the ' 90s when tubes got scarce. Market demand caused a few tube plants to open or expand.

If there is sufficient demand, tubes will get made one way or another. If not, they won't.

I once got to try a couple prototype 12AX7 tubes that had solid state circuits inside. AT&T I think had commissioned them. This is a possible way to go as well.

I agree.

I cannot think of another major source for valves in the current market than for making guitar Amps/gear. Maybe the odd bespoke hi-fi but the biggest consumers (as far as I know) is musicians. The only reason a valve manufacturer would cease is if there is no demand for Valves. Its not just new builds of course but if they were stop using valves in 'new' builds, unless the Valve manufacturers are making other products, I can't see a factory staying open just to cover the numerous owners need for replacement valves. A factory that also makes other products could reduce their valve manufacturing for those who may need to replace valves in older amps but if they stop making valve amps, that would be a big blow for valve manufacturers.

There will be a number of people who will 'refuse' to give up their valve amp preference, want the 'traditional' and believe that it cannot be beat - much like those who still buy Vinyl records. Not that there is anything wrong with that as I am still somewhat a traditionalist myself in numerous areas - I don't buy music, video games etc in formats that I can't hold and put on my shelf and much prefer books, magazines etc than using an eReader or my laptop to read them. I love the sound of a cranked Valve amp and not only hear but feel the music because of the movement of air. There will be others too that want what Valves offer and, to be honest, I can't see the big Amp manufacturers giving up to digital solutions. I can see them coming to some compromise - much like the PT15 and I believe there are power stage units that are designed for pre-amp pedals (isn't that what the Orange Pedal Baby is??) and I guess you could use these after a model of the pre-amp in a 'Helix' (or similar) multi-fx unit.

Regardless of what comes along, even if its superior to the point that even die-hard valve users prefer the sound and feel in a blind test, there will be a portion of the guitarists that will still want valve amps. Any area that is 'weaker' on the Valve amps would be 'character', part of its charm etc - like CD's being too 'clean' without the hiss and crackle of a Vinyl record. Even if the majority do swap to newer solutions, there will be a lot of guitarists that will still want the valve experience like those that still buy physical formats for their music rather than buy it digitally. Hopefully there will be a big enough market for valves to ensure at least one (or more) factory will continue to make them.
 
Ultimately when any product gets phased out, it gets expensive. So those players who just must have tubes better have some $ to burn.

If it's enough money, somebody will continue to make them.
 
Ultimately when any product gets phased out, it gets expensive. So those players who just must have tubes better have some $ to burn.

If it's enough money, somebody will continue to make them.

As if to prove your point, a company called European Audio Team in the Czech Republic has been making a very high end KT88 and 300B for about 15 years. They once had a video on the web that I saw, and it includes processes like hand-blowing the glass for the tube, making very high quality sub-assemblies, etc. And you’d be right if you thought they’d be expensive. They are: $425 per tube.

They’ve gotten stellar reviews in the hi-fi press, and won all kinds of awards.

Yes, I would spend $850 for a pair of special tubes for my HXDA without batting an eye, so I’m probably better off not being able to use KT88s in it (it will run EL34s, KT77s, 6L6, 6CA7 - which at one time was interchangeable with the EL34 but slightly different, and later was the same tube.

I have been eyeing some NOS double-getter Mullard EL34s at $299 each. A pair of these cost about $100 more than my new ‘67 Bassman head cost back when I bought it.

Of course, you have to put these things in perspective. My 1968 Firebird 400, loaded, was about $3000 out the door. A $500 amp was not a cheap amp.

But by any measure, a $600 pair of tubes is an expensive pair of tubes!
 
I saw the same video!

To me it was a play to the folks paying $30k for a CD player.

Definitely. Everyone and his brother has a $30K CD player, so really, it isn’t much of a big deal.

But if they made EL34s or KT77s, I’d want a pair for my HXDA. Because I’m looking forward to this conversation at the pearly gates...

“I see from your file that you were L Schefman, is that correct?”

“Yes.”

“Says here you spent $850 on a pair of tubes for your guitar amp.”

“That’s true.”

“Shut up! Really?”

“Oh yeah. Amps were a thing for me when I was alive.”

“I’m trying to put that into a category. Let’s see...hmmm...it’s not gluttony...and if you’re blowing the money on tubes it’s not avarice...well, I’m just going to put it down as ‘random deadly sin’, because I can’t find a better category for it, and...oh are you kidding? My computer’s down!”

“How can that happen here? Isn’t everything supposed to be magical and perfect? Why do you even need a computer, can’t you just think stuff and it automatically happens?”

“That’s only in heaven. This is limbo. We kind of get the short end of the metaphysical budget here. Just a sec. Hey, Isaiah, can you come here for a minute and help me out? My computer’s on the fritz again...Well I guess I don’t need my computer to figure out where you’re going.” (Takes out a big red rubber stamp, and slams it onto the file, WHOMP!). “Take this folder over to the guy with the horns at the counter, tell him you’ve been interviewed and you need a donkey to take you to hell. Next!”

“Wait, uh...first answer one question. Was it the tubes?”

“Sort of. Crazy people like you who’d blow that kind of money on tubes aren’t really allowed into heaven. Next!”

“Hang on a sec...do they have music in hell?”

“Yes, Polkas, played with accordions. You have your choice of instrument when you enter the mouth of hell. You can get a red accordion, or a sparkle silver accordion. OK? Next!!”

“I like accordions. I can play Polkas.”

“Oh geez, another one! You like accordions. That means hell will be enjoyable for you. I have to reclassify you now. Let’s see...likes accordions....no, that’s aardvarks...yes there it is, likes accordions. (Puts file in a new folder, stamps the cover with a different big stamp. Whomp!). OK, take this folder to the angel in the next cubicle, and she’ll open the pearly gates for you.”

“I’m going to heaven?”

“We have no other place to put you. But you won’t like the music, so for you, heaven will be hell. Next!”

“What’s the music like?”

“Herman’s Hermits, Patti Page, Pat Boone; you know, happy music. God likes happy, clean music. 24/7. Next!!”

“What? No Stairway?”
 
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Definitely. Everyone and his brother has a $30K CD player, so really, it isn’t much of a big deal.

But if they made EL34s or KT77s, I’d want a pair for my HXDA. Because I’m looking forward to this conversation at the pearly gates...

“I see from your file that you were L Schefman, is that correct?”

“Yes.”

“Says here you spent $850 on a pair of tubes for your guitar amp.”

“That’s true.”

“Shut up! Really?”

“Oh yeah. Amps were a thing for me when I was alive.”

“I’m trying to put that into a category. Let’s see...hmmm...it’s not gluttony...and if you’re blowing the money on tubes it’s not avarice...well, I’m just going to put it down as ‘random deadly sin’, because I can’t find a better category for it, and...oh are you kidding? My computer’s down!”

“How can that happen here? Isn’t everything supposed to be magical and perfect? Why do you even need a computer, can’t you just think stuff and it automatically happens?”

“That’s only in heaven. This is limbo. We kind of get the short end of the metaphysical budget here. Just a sec. Hey, Isaiah, can you come here for a minute and help me out? My computer’s on the fritz again...Well I guess I don’t need my computer to figure out where you’re going.” (Takes out a big red rubber stamp, and slams it onto the file, WHOMP!). “Take this folder over to the guy with the horns at the counter, tell him you’ve been interviewed and you need a donkey to take you to hell. Next!”

“Wait, uh...first answer one question. Was it the tubes?”

“Sort of. Crazy people like you who’d blow that kind of money on tubes aren’t really allowed into heaven. Next!”

“Hang on a sec...do they have music in hell?”

“Yes, Polkas, played with accordions. You have your choice of instrument when you enter the mouth of hell. You can get a red accordion, or a sparkle silver accordion. OK? Next!!”

“I like accordions. I can play Polkas.”

“Oh geez, another one! You like accordions. That means hell will be enjoyable for you. I have to reclassify you now. Let’s see...likes accordions....no, that’s aardvarks...yes there it is, likes accordions. (Puts file in a new folder, stamps the cover with a different big stamp. Whomp!). OK, take this folder to the angel in the next cubicle, and she’ll open the pearly gates for you.”

“I’m going to heaven?”

“We have no other place to put you. But you won’t like the music, so for you, heaven will be hell. Next!”

“What’s the music like?”

“Herman’s Hermits, Patti Page, Pat Boone; you know, happy music. God likes happy, clean music. 24/7. Next!!”

“What? No Stairway?”
If there were such a thing as God, he’d be listening to Bach, astonished at the paradoxical idea that he could create the man, but couldn’t come close to creating the man’s music. Then he just chalk it up to another higher level by product of free will
 
If there were such a thing as God, he’d be listening to Bach, astonished at the paradoxical idea that he could create the man, but couldn’t come close to creating the man’s music. Then he just chalk it up to another higher level by product of free will

Nah. Omnipotent beings can’t be astonished, because they already know what’s going to happen.

“C’mon, Les, free will or determinism?”

“The philosophical problem with determinism is that it assumes a determinist. Free will assumes that the determiner exists, but takes a ‘hands off’ stance for one creature, just because. Neither can be proven.”

“What do you think, Les?”

“Let’s see what Obi-wan thinks instead.”

 
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In the end it's all deterministic. Knowing the outcome of every action, acting once determines all outcomes, regardless of free will.
 
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