3 ms·

Price and weight are close. About $2500. AxeFx III is about ~6.8 Kg. Between a half and a third of a Plexi head or an AC-30 Head. For a stadium band. It makes

Price and weight are close. About $2500. AxeFx III is about ~6.8 Kg. Between a half and a third of a Plexi head or an AC-30 Head. For a stadium band. It makes the stage setup much easier. No cabinets, mics and low stage volume. Each member gets a rack with two units (backup) and you are done. Sound will be always the same. Less likely to fail. For a small band, you don't need the bulky rack editions. You get the same sound quality in pedal form (Helix, FM-3, etc). It can be carried in a bag. In both cases, the sound engineer has an easier job. You plug your devices directly to the mixer/Front of House. Most musicians program few pre-defined rigs, but a device like this gives you not only one sound, but the sound of ~300 amplifier models including some rare collection items.

qppo 6y ago
Yes you have more control, it also sounds worse. They have advantages in live reproduction, yet you still see tubes mic'd up in the studio. And for a small band even if you have a FoH mix, it's going to sound better out of a 40W combo than through whatever PA your vocalist dragged along. But that's just my opinion. Digital models do a good job in a vacuum (no pun intended). They do a very poor job of modeling how a guitar and FX chain load and drive the preamp of an real tube amplifier (which is really difficult to capture in either white or black box models). That's also a key to getting lush and evocative ranges of tone from a single configuration. Just speaking as a player, I don't really fiddle with my tube amps all that much. The tone changes come from dynamics of my hands and controls over my pickup volume controls, and it's accentuated by my drive and boost pedals. That kind of play doesn't translate well to modeling amps which don't have the low headroom, lower impedance inputs of a pure tube stage. I don't need 300 different amp models, I need 1 amp model for 300 tones.
- ReactiveJelly 6y ago
  > They do a very poor job of modeling how a guitar and FX chain load and drive the preamp of an real tube amplifier Are there ABX tests for digital vs. physical tubes?
  - klodolph 6y ago
    There are a ton of people doing ad-hoc stuff like this on YouTube if you search for it. ABX test is definitely the wrong type of test here. It is only really useful for testing if there are differences, and in general a tube amp and a digital sim are not going to sound the same as each other. What I’ve seen as more common is that you’ll have someone playing blind through a selection of digital models and tube amps. If you’re lucky, the digital models and tube amps may be closely matched, but that’s not necessarily the only way you would want to run a test. There are also an incredible number of different scenarios that need to be taken into account in a simulation, so you’d want to try different styles of amp. Various overdrive scenarios are harder to simulate, broadly speaking. https://www.youtube.com/watch?v=k6AwTp4ZUm0 https://www.youtube.com/watch?v=k6AwTp4ZUm0 Note in this video, the speakers are being simulated for the tube amps. So it’s a bit of an unusual comparison, it’s just something I found.
- klodolph 6y ago
  > …lower impedance inputs of a pure tube stage… I don’t know what your idea of “lower impedance” but a pure tube stage has an input impedance that measures close to open. Off the range of my multimeter, I bet. You just see the Miller capacitance and with the grid-plate somewhere around 1.6pF and maybe 20dB gain, it’s not a lot. The input impedance of the guitar amp is usually dominated by the 1 MΩ resistor to ground, and the tube barely registers because the input impedance of a preamp tube is so high. This is usually considered “high impedance” (as opposed to “ultra high” like you see in a piezo amp, which might run 10 MΩ). It is very common to see solid-state equipment with lower input impedances, especially guitar pedals. There’s a lot of weird voodoo electronics repeated around guitarist’s forums so you got to watch out. Just quick fact check: small tubes = high impedance input, in most normal configurations, normal operating conditions (cathode is positive relative to grid). Just as another point of reference—this is why you hear about “tube microphones”. These microphones have a vacuum tube inside them as a preamp / buffer, and the reason you might want to use a tube for these applications is precisely because the input impedance is so high. When they moved away from tube mics what you see replacing them is something like a FET, possibly bootstrapped, to try and replicate the naturally high impedance of a tube.
  - fuzzfactor 6y ago
    Yes the input impedance of a good tube is much higher than the typical 1 Megohm resistor referencing it to ground. That's a million ohms so not much of your guitar signal is wasted passing through it to ground. The input impedance of the tube reacts dynamically according to the signal coming in, and the often dynamic behavior of whatever is plugged directly into it. When that's just your guitar without any pedals or anything, that can be the most dynamic from a touch-sensitive point of view.
irscott 6y ago
Nobody is buying or playing those big heads these days. It's super rare to see people buying tube amps above the 50w range even for stage use. They're just too loud and unweildy and weigh an absolute ton. I've been in high end music retail for several years and even the big name stars we deal with are buying primarily combo tube amps in the 40w range.

qppo 6y ago

Yes you have more control, it also sounds worse. They have advantages in live reproduction, yet you still see tubes mic'd up in the studio. And for a small band even if you have a FoH mix, it's going to sound better out of a 40W combo than through whatever PA your vocalist dragged along. But that's just my opinion. Digital models do a good job in a vacuum (no pun intended). They do a very poor job of modeling how a guitar and FX chain load and drive the preamp of an real tube amplifier (which is really difficult to capture in either white or black box models). That's also a key to getting lush and evocative ranges of tone from a single configuration. Just speaking as a player, I don't really fiddle with my tube amps all that much. The tone changes come from dynamics of my hands and controls over my pickup volume controls, and it's accentuated by my drive and boost pedals. That kind of play doesn't translate well to modeling amps which don't have the low headroom, lower impedance inputs of a pure tube stage. I don't need 300 different amp models, I need 1 amp model for 300 tones.

ReactiveJelly 6y ago
> They do a very poor job of modeling how a guitar and FX chain load and drive the preamp of an real tube amplifier Are there ABX tests for digital vs. physical tubes?
- klodolph 6y ago
  There are a ton of people doing ad-hoc stuff like this on YouTube if you search for it. ABX test is definitely the wrong type of test here. It is only really useful for testing if there are differences, and in general a tube amp and a digital sim are not going to sound the same as each other. What I’ve seen as more common is that you’ll have someone playing blind through a selection of digital models and tube amps. If you’re lucky, the digital models and tube amps may be closely matched, but that’s not necessarily the only way you would want to run a test. There are also an incredible number of different scenarios that need to be taken into account in a simulation, so you’d want to try different styles of amp. Various overdrive scenarios are harder to simulate, broadly speaking. https://www.youtube.com/watch?v=k6AwTp4ZUm0 https://www.youtube.com/watch?v=k6AwTp4ZUm0 Note in this video, the speakers are being simulated for the tube amps. So it’s a bit of an unusual comparison, it’s just something I found.
klodolph 6y ago
> …lower impedance inputs of a pure tube stage… I don’t know what your idea of “lower impedance” but a pure tube stage has an input impedance that measures close to open. Off the range of my multimeter, I bet. You just see the Miller capacitance and with the grid-plate somewhere around 1.6pF and maybe 20dB gain, it’s not a lot. The input impedance of the guitar amp is usually dominated by the 1 MΩ resistor to ground, and the tube barely registers because the input impedance of a preamp tube is so high. This is usually considered “high impedance” (as opposed to “ultra high” like you see in a piezo amp, which might run 10 MΩ). It is very common to see solid-state equipment with lower input impedances, especially guitar pedals. There’s a lot of weird voodoo electronics repeated around guitarist’s forums so you got to watch out. Just quick fact check: small tubes = high impedance input, in most normal configurations, normal operating conditions (cathode is positive relative to grid). Just as another point of reference—this is why you hear about “tube microphones”. These microphones have a vacuum tube inside them as a preamp / buffer, and the reason you might want to use a tube for these applications is precisely because the input impedance is so high. When they moved away from tube mics what you see replacing them is something like a FET, possibly bootstrapped, to try and replicate the naturally high impedance of a tube.
- fuzzfactor 6y ago
  Yes the input impedance of a good tube is much higher than the typical 1 Megohm resistor referencing it to ground. That's a million ohms so not much of your guitar signal is wasted passing through it to ground. The input impedance of the tube reacts dynamically according to the signal coming in, and the often dynamic behavior of whatever is plugged directly into it. When that's just your guitar without any pedals or anything, that can be the most dynamic from a touch-sensitive point of view.

irscott 6y ago

Nobody is buying or playing those big heads these days. It's super rare to see people buying tube amps above the 50w range even for stage use. They're just too loud and unweildy and weigh an absolute ton. I've been in high end music retail for several years and even the big name stars we deal with are buying primarily combo tube amps in the 40w range.