I had a Katana amp for a while.
The artist has the same amp models, effects and abilities to download cab sims.
So yes, it is a modeller.
You can download patches from the boss tonelab if you’re so inclined.
The big differences (from memory) were that the artist series had Midi and a much better speaker. It’s a VERY nice sounding amp. 
Wow! That’s cool. So I just download the patch I like and what do I do next? Sorry @HowlinDawg I’m such a noob, lol. I’m trying to fill my first 4 preset then hopefully do the rest as I get better, thanks.
Play. 
You put it into one of the presets.
I think there are six slots you can drop patches into.
Justin has a series of videos on it - I’m not sure how up to date they are though.
Cool. There are 8, 4 on each bank on mine if I understand that part correctly.
Thanks @HowlinDawg
This just came up on TalkBass (apropos; then again, it also was posted yesterday 
):
https://www.talkbass.com/threads/why-vacuum-tube-amps-are-louder-the-truth-of-natural-even-harmonic-phase-rotation.1602311/
roughly 50% louder i would think. you can roughly estimate that his 15w amp is putting out around 96 dB (assuming 85 dB sensitivity, which actually may be pretty low for a guitar amp) and 100w would be around 6 dB or so louder. 96 dB doesn’t seem like a lot, roughly jazz music territory, but guitar is sooo treble-y and piercing it just cuts through everything.
That’s fantastic!
But what if we spin around while we play through the Berg? We’ll get the same effect, no? 
Only one way to find out - looking forward to the video proof 
When I gigged with a previous band in Lyon (2nd or 3rd biggest city in France), my amp was a Hayseed 30 which is more or less a boutique version of a '63 JMI Vox AC30. This amp has 4 EL84 power tubes for exactly 36w, with a half-power mode (which uses only 2 power tubes) for 18w. When playing live with this amp, I never used the 36w mode. Never.
By the way I still have this amp and I still love it, like on the first day.
Now my main guitar amp is a '07 Bad Cat Hot Cat, 30w with no half-power mode. That’s loud.
Very cool Paul, I also have a KC-220 new in the box… just have never used it yet. It’s a good thing the KC-600 has wheels on it because you’re correct, it’s a beast in more ways than one. Thanks for the reply, cheers! Dale
It’s not that they have to be measured differently, but it’s kinda turned out that way.
In days gone by there were no standards for how power was to be measured and even now that standards exist no one is required to use them or tell you how they made their measurement. High end PA systems are engineered, so real math has to happen and engineers won’t use things without valid specifications. The music market tends to be a little more marketing oriented.
For analogue amps power has often been measured by putting a broadband (across the frequency range of interest) pink noise signal into an amp and turning it up until it distorts. The question is how much distortion is allowable for the power rating. Maybe a high quality amp allows 0.05% Total Harmonic Distortion, maybe something else 1%, maybe something else 10%. The nice thing about analogue amps are that they are more forgiving if you go above their limit. They just have some gentle distortion that in many cases people liked. If you drive an analogue amp into distortion, you are running it above its power rating.
When we talk about power or level numbers in audio, we are concerned with the average and the peak. Sharp attacks are going to hit peaks and the note ringing out is going to be our average. The pink noise signal used to determine the power rating usually has a crest factor (distance between the average and the peak) of 6dB. Each 3dB is a doubling of power. Soooo, if we measure an amp to have an average power rating of 200 Watts for a particular total harmonic distortion, we are going to double that twice (6dB) to get the peak power rating of 800 Watts (because the pink noise used has a crest factor of 6dB).
Digital devices don’t distort nicely at all when overloaded. If you get into distortion, they fall off a cliff and become unusable very quickly. So, we really care a lot about that peak number and then have to back down from there. The difference is that a well designed digital amp has very low harmonic distortion all the way up to it’s maximum peak; it doesn’t really degrade. And with a well designed digital amp, it is also possible to sustain that high level for a long time. But these nice digital amps were getting short changed on the spec sheet because their advantages didn’t shine using the traditional test methods.
There was some talk that music is a lot different from pink noise and you can actually get much more power out of an amp with music than the pink noise test would say you could. So the Audio Engineering Society (AES) wrote an amp power test standard using a burst signal rather than pink noise which digital amp makers began to use. This produces a higher baseline power rating, but leaves less in headroom, so it is closer to the peak number. This skews the power ratings higher in modern digital amps. Manufacturers may be giving you the peak number rather than the average number if they don’t say.
In this forum we usually talk about compression in the context of the musical character of the playing, but here compression applies to how loud your average level can be. The more you compress the sharp transient sounds, the more you can turn up the amp and make your average level louder. Compression means you are decreasing the distance between the average and the peak. This means you will have more rumble level, but less impact on the pluck.
The linked article brings up two other relevant factors. A valve amp has connections for both a 4 ohm and an 8 ohm cabinet, so it will always deliver its max rated power. If you hook most digital amps up to an 8 Ohm cabinet, you only get half the power rating on the label. (A few exceptions exist)
The other is the sensitivity of the cabinet. In one cabinet maybe you get 97dB-SPL out of it at 1 meter away if you put in 1 Watt. In another cabinet maybe you get 91dB-SPL out of it at 1 meter away if you put in 1 Watt. If you put a 200 Watt amp on the 97dB cabinet, you will need to put a 800 Watt amp on the 91dB cabinet to get the same level (6dB difference requires doubling the power twice). This makes power and level comparisons very difficult.
Thanks for another excellent post, Dave.
This is actually always the right way to think about compression, even on pedalboards. It’s a lot easier to understand when you think of it as increasing the general loudness of the signal compared to the peaks.
I think most people think of compression in terms of limiting, which is only part of the story.
Thanks @DaveT I could follow along and didn’t need any pictures either.
I love this forum for stuff like this.
Thanks for the masterclass @DaveT, it just sum up amp power in the nutshell. I enjoyed that very much.
Sorry for the bad pictures but I wanted to show you the cab I made by converting my Line6 Lowdown 300 Pro combo into a separate cab and head. The head is not finished yet but I’ll post pictures when it’s done.
The cab is a 1x15" 300w under 8Ω, it’s built like a tank (heavy AF) and the low frequencies are really impressive. It works fine either with vintage-style tones and more modern clean tones, but it’s a bit blurry in the low end with saturation. Probably just too much low end for this.
I’m considering trading or selling it because I’d prefer a lighter 1x12" or 2x10" cab. But this 1x15" is quite good so it’s not really a problem if I just keep it.
Do you have a before picture?
Dang @terb! You do good work. It doesn’t look like it was ever a combo amp.
Nice @terb interesting how they use the banana plug connection.
that’s something that I added, in fact there were no plug at all because the connexion between the “cab” and the “head” was all internal. I found those plugs so I said, why not 
