+1 All music passes through some form of distorting filter before it gets to your brain, even live music. Even Carnegie Hall "adds something". "Perfection" is chosen not given. It can come from 1,000 different system/room profiles playing the same recording. We've all listened to well recorded 40's music full of rich harmonics obviously "added" by the tubes, just think of an old Bing Crosby album, talk about your 2nd harmonics. But its perfect the way it is, sound wise!
Amplifiers are probably the least intrusive "effects box" in the whole audio reproduction chain unless its obviously clipping.
I think, when it comes to pushing current into a loud speaker, a vacuum tube does it better.......
Actually, not so.
Depending on the power supply, and if it's prone to sag, as they mostly are, transistors have more "punch".
That is why a lot of bass players prefer solid state bass amps over tube types.
Actually no.
I wrote a science paper as thesis in my last graduates physics class on this.
I conjectured current flow through a vacuum tube travels through the tube about(s) the speed of light. Current flow through a transistor travels through the silicon, about(s) 1/10 the speed of light, which generates a great deal of waste heat, and thus generates a fair amount of audio distortion.
I wrote a science paper as thesis in my last graduates physics class on this.
I conjectured current flow through a vacuum tube travels through the tube about(s) the speed of light. Current flow through a transistor travels through the silicon, about(s) 1/10 the speed of light, which generates a great deal of waste heat, and thus generates a fair amount of audio distortion.
How could you post something like this Dr. Moore? You stated that you are a Ph.D., you should maintain correct scientific facts. Electron speed in vacuum tubes is much less than 1% of C, there would be high xray emission otherwise.
speed of current flow through a wire slower.....
speed of current flow through a slab of rock, much slower still.... that was my point . . . . . .
speed of current flow through a slab of rock, much slower still.... that was my point . . . . . .
I call BS, And i can disprove it with Physics I learnt at 15.
electron mass =
9.10938356 × 10-31 kilograms
Light speed. 299792458.00 m/s
Formula for Kinetic energy: 1/2*m*V*V
Kinetic energy of a single electron hitting the anode :
9.10938356 × 10-31 * ((299792458.00)*(299792458.00) = 8.0887966e-14
1 AMP expressed in electrons per second = 6.242 × 1018
1mA expressed in electrons per second =6.242x10 ^15
1mA of cathode current will smash 6.242*10^15 electrons into the anode at the speed of light, we have just calculated the kinetic energy for a single electron traveling at the speed of light at about 8*10^-14 Jules. if we multiply these factors. we get about 500 jules of kinetic energy for 1mA of cathode current.
So a 12AX7 running at 1mA plate current will need a plate dissipation of 500 watts or more. Now even if it were only half the speed of light, thats still 125W
Now say we were running a 50mA 6L6 output tube, it would need a plate dissipation of about 25KW just to maintain a constant temperature at the anode. Given that these formula are quadratic, I'd say you were off by At LEAST two orders of magnitude.
I removed some savage remarks in the edit. Too easy.
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Ballistic velocity of electrons in a small vacuum tube is more like 10,000 km/s, not 300,000 km/s.
http://mitp-content-server.mit.edu:..._pres_0&id=1313&fn=9780262571906_sch_0001.pdf
http://mitp-content-server.mit.edu:..._pres_0&id=1313&fn=9780262571906_sch_0001.pdf
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Well now, according to the posts here after you insisted that I'm wrong, (my thanks to those replies) it seems you need to go back to your physics class.
Best not to go up against an old retired and experienced service tech like me. 😱
Overstating it a bit? A decent valve pre, unless using DHTs, should have no issues with that. What about those lovely Linn power amps from the mid 80s that had an input impedance of 2.6k?
Allright, some constructive remarks from my part, electrons move through a conductor in several feet per minute, depening on the conductor in question. (As far as i know)
Claiming without knowing that something travels at the speed of light is kind of funny. I was like that cant be true! Once you accelerate anything to the speed of light the forces involved are enormous.
A single golfball at the speed of light is going to have more kinetic energy than the nuclear arsenal of some countries.
Here are the calculations for a grain of sand.
A grain of sand, 0.005 grams for example, is 5*10-6Kg
0.5 *5*10-6 * ((299 792 458)(299 792 458)) = 2.5e-6* 8.9875518e+16 = roughly 25e10J
or 2.5e11 Joules. That is approximately 50 Tons of TNT equivalent.
A golfball is 10.000 heavier so will have a energy of about 500KT about 25 times the energy of the Hiroshima bomb.
Claiming without knowing that something travels at the speed of light is kind of funny. I was like that cant be true! Once you accelerate anything to the speed of light the forces involved are enormous.
A single golfball at the speed of light is going to have more kinetic energy than the nuclear arsenal of some countries.
Here are the calculations for a grain of sand.
A grain of sand, 0.005 grams for example, is 5*10-6Kg
0.5 *5*10-6 * ((299 792 458)(299 792 458)) = 2.5e-6* 8.9875518e+16 = roughly 25e10J
or 2.5e11 Joules. That is approximately 50 Tons of TNT equivalent.
A golfball is 10.000 heavier so will have a energy of about 500KT about 25 times the energy of the Hiroshima bomb.
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The Johnson T15R hybrid guitar combo has a 12AX7 input stage and an integrated circuit power amplifier. The tube has low anode voltage for achieving even more "tubey" sound. The tube/bypass ratio can be adjusted with a knob. Several companies licensed it, I met the AXL (Chinese version).
The speed of light in a vacuum is the limiting velocity of the Universe. It is possible to exceed the speed of light in media other than a vacuum. See Cherenkov effect.
Obviously no one ask for the opposite way around.
There are some qualities in audio sound that are quite exclusive achievable with tubes.
A kind of transparency in sound in combination with the best things transistor sound has to offer. Its not easy to achieve those qualities and most middle class tube audio gear is unable to, but I've only heard them with electron tubes in real high end audio systems. Whatever someone understand with this term, but for me its about a very special audio sound unique to tubes.
There are some qualities in audio sound that are quite exclusive achievable with tubes.
A kind of transparency in sound in combination with the best things transistor sound has to offer. Its not easy to achieve those qualities and most middle class tube audio gear is unable to, but I've only heard them with electron tubes in real high end audio systems. Whatever someone understand with this term, but for me its about a very special audio sound unique to tubes.
I use a tube microphone pre-amp in my mobile sound rig to sweeten up the sound when DJs use a digital source. It's an ART Digital MPA-II that I bought used on Ebay for $300 with an upgraded set of matched tubes. Plenty of control over how much tube sauce is in the mix. Also it has a decent ADC inside, although there is a model out there without one. XLR ins and outs, also AES and optical. I like it very much, especially for the $$$. It is a 2U rack unit however.
BTW, For many years on my home system I have been using a plugin for Foobar2000 called Ozone MP. Besides a very granular (control, not sound!) tube drive simulator, you get a spatializer and parametric EQ. It sounds great.
BTW, For many years on my home system I have been using a plugin for Foobar2000 called Ozone MP. Besides a very granular (control, not sound!) tube drive simulator, you get a spatializer and parametric EQ. It sounds great.
How about this device? it does the job and more.
micro iTube2 by iFi audio | Vacuum Tube Buffer and Line Stage Preamplifier
micro iTube2 by iFi audio | Vacuum Tube Buffer and Line Stage Preamplifier