Cool concept, but I doubt the operating range of these tubes is large enough to get any sort of usable gain out. Unless there's a datasheet that says otherwise I'd imagine these are going to end up early in the gain chain as a "coloring" component.
With the low operating range and low bias point you don't get the same effect as you do with a tube biased to it's sweet spot. It seems like a marketing gimmick like the starved-plate 12ax7 stage they put in everything nowadays (with ~12V B+ as opposed to the 250-400V B+ you find in nearly all classic amp designs), along with a few LEDs and a window in front so you can see where your extra $100 is going.
If you plot (really any) load line on the plate curves for a 12AX7 with a < 50V B+ you're in a really poor, highly non-linear region. Looking at plate curves for some old VFD tubes the operating range for those is way down in the same region in the lower left corner if you plot them over the 12AX7 plate curves.
Given the size and the fact that it uses 2% of the power of conventional tubes, I doubt that these tubes could be used as an output stage. I would have to guess that they're running them cold as well. Preamp tube power draw is often dominated by the heaters
Of course this is all speculation until they publish a datasheet...
I find most cheap tube gear uninteresting, musically speaking. It's generally, as you note, a tiny low voltage 12AX7 preamp stage feeding a regular old transistor gain stage. There's a reason the old master volume Marshall amps are sought after, and why so many manufacturers have returned to all-tube designs.
Some of what goes on in audio is snake oil. In fact, a lot of it is. But, modeling amps and tube preamp stage gear still doesn't hold up well against a good tube amp. I bought a new amp a couple years ago, after having used the same amp for ~20 years (a 1984 JCM 800). I tried every amp in the small size range at two guitar stores. The clear winner was an all-tube Vox model. The modeling amps were way down the list, which was disappointing. I really believed we had the technology to replicate good amp tone (and some guitar amp sims on computer are reasonably good)...but we still aren't there.
And, the preamp tube with transistor volume stage amps were also clearly inferior to the master volume style all-tube amp I ended up buying.
Why is early in the gain chain necessarily bad? Suppose the later stages of the chain introduce no distortion, would it be possible (in theory) to have low power devices like this create all the nonlinear effects considered desirable by audiophiles and then just amplify that later on?
That's a two-segment vacuum fluorescent display! If you want to do your own "tube" experiments, you can find these in salvaged electrical gear, especially VCRs.
Based on that article, I'm not convinced that it's the best that the part could do, based on the circuit schematic. We would not be using the windings of a transformer as a load in a typical gain stage in a musical instrument preamp. A typical inverting stage would have a large-ish resistor as its load, in parallel with the fairly high impedance of the next stage (another tube circuit that is similar).
Generally with tube amps there are two places the tubes can go, either the preamp stage or the output stage. Most tube amp enthusiasts will scoff at the idea of having only a preamp tube stage and not power tube stage. These things look tiny, I'd be impressed if these can deliver the wattage required by output tubes.
Also interesting will be to hear how they actually sound. All tubes aren't built equal, and even with traditional tubes you can find people arguing about the merits of the 6L6 or EL-34.
Of course, if this thing delivers on both fronts that would be incredible. Tubes are in short supply, and my friends who play on tube amps are always complaining out how expensive it is to replace the damn things.
Maintenance is expensive for sure and new old stock is scarce. But there it's not only tube amps vs solid state amps, there are also modeling amps. They've been around for more than a decade and they are able to simulate the effect of tube amplification and even model each electronic component individually. Well at least they pretend they do. And anyway even if they did guitarist would not buy them because they are a little conservative.
unrelated aside since you linked to such an interesting web page.
this 1940 vacuum tube hearing aid used a bone-conducting transducer scheme.[1] I was stuck thinking that was a fairly new concept (at least from the 80s) for military comms, and was intrigued by the use of such tech in the recent Google Glass.
It's cool to see that the idea was much older than I realized.
If they put the same coating on the anode as what they put in the vacuum-fluorescent displays, it will have more than just that warm glow. It will flicker green.
From the photo, it looks like that may be the case: what are those green squares? The form factor is like that of a VFD.
It is quite suggestive of the intent that the part will be mounted such that it is visible through a display window in the equipment's case.
I'm surprised the government didn't outlaw tubes along with all the incandescent bulbs. That's just the kind of collateral damage they never seem to consider.
They're highly non-linear wrt amplitude and frequency, in a pleasing way.
This makes them almost instruments in their own right. When playing a guitar through heavy tube distortion, the tubes react to your playing very sensitively, just like the guitar itself does.
When people describe random pieces of electronic equipment as "musical" this is usually what they mean.
This applies to IC amps as well, but not to the same extent. The recent history of music tech is a story of working hard with esoteric techniques to produce amazing music from primitive gear in the 60s and 70s, then inventing more reliable and repeatable techniques using digital technology in the 80s and 90s.
In recent years, people are realising that the man-vs-machine-vs-physics attrition of the mid to late 20th century actually led to a certain sonic complexity that has been missing in recent years. So now we see these hybrid products which merge old and new technology to get a deep sound while retaining reliability and a good workflow.
See also: analog voltage controlled oscillators which automatically tune themselves using digital clocks, and compensate for temerature changes.
(Incidentally, a lot of audiophile nonsense stems from them making category errors between their puported search for crystal clear reproduction, and studio engineers' quest for signal distortion with emotional quality. This is similar to how MBA types cargo cult programming terminology.)
I will expand on a comment below. Tubes usually distort with even order harmonics which means the distortion is usually in key with the note and our brains find this distortion pleasing. Transistors distort with odd order harmonics which sounds more dissonant and harsh to the ears. Transistors also tend to be clean or clip, there is little to no build up. Tubes saturate gradually and can make things sound "warmer, fuller and generally awesome".
Not all tubes are great though and it doesn't look like these are power tubes so it would be for preamp/line level gear only. Either way I'm really excited to see this.
I don't see where the article says that they are. It says that the tubes are designed for musical instrument applications to generate rich harmonics. Essentially, the distortion characteristics of a tube amplifier are different from those of modern designs, and these characteristics are sometimes desired in for example guitar distortion pedals.
Korg has previously released synthesizers and a sampler using vacuum tubes for effect rather than to make them "better" in any objective sense.
it plays into that old joke about audiophiles listening to hardware. Perhaps the distortion has properties that ICs fail to emulate, or likely put three of these guys in a room and a blind listening test will have four results.
[+] [-] hamiltonkibbe|11 years ago|reply
With the low operating range and low bias point you don't get the same effect as you do with a tube biased to it's sweet spot. It seems like a marketing gimmick like the starved-plate 12ax7 stage they put in everything nowadays (with ~12V B+ as opposed to the 250-400V B+ you find in nearly all classic amp designs), along with a few LEDs and a window in front so you can see where your extra $100 is going.
If you plot (really any) load line on the plate curves for a 12AX7 with a < 50V B+ you're in a really poor, highly non-linear region. Looking at plate curves for some old VFD tubes the operating range for those is way down in the same region in the lower left corner if you plot them over the 12AX7 plate curves.
Given the size and the fact that it uses 2% of the power of conventional tubes, I doubt that these tubes could be used as an output stage. I would have to guess that they're running them cold as well. Preamp tube power draw is often dominated by the heaters
Of course this is all speculation until they publish a datasheet...
[+] [-] SwellJoe|11 years ago|reply
Some of what goes on in audio is snake oil. In fact, a lot of it is. But, modeling amps and tube preamp stage gear still doesn't hold up well against a good tube amp. I bought a new amp a couple years ago, after having used the same amp for ~20 years (a 1984 JCM 800). I tried every amp in the small size range at two guitar stores. The clear winner was an all-tube Vox model. The modeling amps were way down the list, which was disappointing. I really believed we had the technology to replicate good amp tone (and some guitar amp sims on computer are reasonably good)...but we still aren't there.
And, the preamp tube with transistor volume stage amps were also clearly inferior to the master volume style all-tube amp I ended up buying.
[+] [-] grandalf|11 years ago|reply
[+] [-] illicium|11 years ago|reply
[+] [-] pjc50|11 years ago|reply
[+] [-] fnordfnordfnord|11 years ago|reply
[+] [-] sbierwagen|11 years ago|reply
[+] [-] kazinator|11 years ago|reply
[+] [-] nharada|11 years ago|reply
Also interesting will be to hear how they actually sound. All tubes aren't built equal, and even with traditional tubes you can find people arguing about the merits of the 6L6 or EL-34.
Of course, if this thing delivers on both fronts that would be incredible. Tubes are in short supply, and my friends who play on tube amps are always complaining out how expensive it is to replace the damn things.
[+] [-] jdmoreira|11 years ago|reply
(at least that's my guess)
[+] [-] kubiiii|11 years ago|reply
[+] [-] kazinator|11 years ago|reply
Also, when tubes were in their heyday, there existed miniature tubes: perhaps not as small as this new one, but a lot smaller than a 12AX7/ECC83.
Check out the vacuum tube hearing aid pages in the Hearing Aid Museum:
http://www.hearingaidmuseum.com/
Can't believe they made kids wear such things. :)
[+] [-] joezydeco|11 years ago|reply
[+] [-] serf|11 years ago|reply
this 1940 vacuum tube hearing aid used a bone-conducting transducer scheme.[1] I was stuck thinking that was a fairly new concept (at least from the 80s) for military comms, and was intrigued by the use of such tech in the recent Google Glass.
It's cool to see that the idea was much older than I realized.
[1]: http://www.hearingaidmuseum.com/gallery/Vacuum%20Tube/Acoust...
[+] [-] Aardwolf|11 years ago|reply
[+] [-] kazinator|11 years ago|reply
From the photo, it looks like that may be the case: what are those green squares? The form factor is like that of a VFD.
It is quite suggestive of the intent that the part will be mounted such that it is visible through a display window in the equipment's case.
[+] [-] droopyEyelids|11 years ago|reply
[+] [-] mark-r|11 years ago|reply
[+] [-] diydsp|11 years ago|reply
But it's confusing: There is already a model of tube called 6P1 (1).
Anyway, who is this for? Engineers/instrument designers? Korg to use internally?
(1) http://en.wikipedia.org/wiki/6P1P
[+] [-] amdolan|11 years ago|reply
This is an important question. I doubt I'll have the chance to use this unless someone in Asia makes a knock off.
[+] [-] arunc|11 years ago|reply
[+] [-] JonnieCache|11 years ago|reply
This makes them almost instruments in their own right. When playing a guitar through heavy tube distortion, the tubes react to your playing very sensitively, just like the guitar itself does.
When people describe random pieces of electronic equipment as "musical" this is usually what they mean.
This applies to IC amps as well, but not to the same extent. The recent history of music tech is a story of working hard with esoteric techniques to produce amazing music from primitive gear in the 60s and 70s, then inventing more reliable and repeatable techniques using digital technology in the 80s and 90s.
In recent years, people are realising that the man-vs-machine-vs-physics attrition of the mid to late 20th century actually led to a certain sonic complexity that has been missing in recent years. So now we see these hybrid products which merge old and new technology to get a deep sound while retaining reliability and a good workflow.
See also: analog voltage controlled oscillators which automatically tune themselves using digital clocks, and compensate for temerature changes.
(Incidentally, a lot of audiophile nonsense stems from them making category errors between their puported search for crystal clear reproduction, and studio engineers' quest for signal distortion with emotional quality. This is similar to how MBA types cargo cult programming terminology.)
[+] [-] S_A_P|11 years ago|reply
[+] [-] boomlinde|11 years ago|reply
Korg has previously released synthesizers and a sampler using vacuum tubes for effect rather than to make them "better" in any objective sense.
[+] [-] Shivetya|11 years ago|reply
[+] [-] mdellabitta|11 years ago|reply
[+] [-] serf|11 years ago|reply
[+] [-] grondilu|11 years ago|reply
http://spectrum.ieee.org/semiconductors/devices/introducing-...
Could be the next big thing in computing. Or not. Only time will tell.
[+] [-] morokhovets|11 years ago|reply
[+] [-] dzhiurgis|11 years ago|reply