11-30-2010, 05:36 PM
I missed seeing this before.
There's no book that will do quite what you want. The internal construction of vacuum tubes was of interest only to the engineers who worked on them. They did whatever was manufacturable at a reasonable cost and met the industry specs. If they had dies on hand for stamping plates with ribs (perhaps because other tubes used the same stampings) that's what they used; another maker might have chosen smooth plates. Getters were bought from outside suppliers because their manufacture was somewhat dangerous: the metals used were unstable. So again, the tube maker used whatever he could buy at the time, that was compatible with his manufacturing processes.
The specific shape of a getter, plate structure, or anything else, is only of interest now as an easy way to identify different products, some of which are assumed to be better than others, often in ways that the original makers wouldn't have dreamed of. It may be that 6L6s with "D" shaped getters (I'm making this up) "sound better" than tubes with washer-shaped getters. If so, it has nothing to do with the getter itself, only that at a certain time, one maker happened to use D-shaped getters and his girls were particularly adept at making good tubes. Whereas the competitor's girls used hand lotion that contaminated theirs. Or, more often than modern audiophiles will admit, there is no difference, but folklore is self-perpetuating (if you paid a lot for a tube or searched for years to find it, it always sounds better). And the differences between tubes must be visually obvious, so your friends will see that you're using the "better" version.
I recommend Robert Tomer's 1960 book "Getting the Most out of Vacuum Tubes" which I've been told is on the net somewhere, which discusses the tube characteristics that really matter, with no nonsense.
There's no book that will do quite what you want. The internal construction of vacuum tubes was of interest only to the engineers who worked on them. They did whatever was manufacturable at a reasonable cost and met the industry specs. If they had dies on hand for stamping plates with ribs (perhaps because other tubes used the same stampings) that's what they used; another maker might have chosen smooth plates. Getters were bought from outside suppliers because their manufacture was somewhat dangerous: the metals used were unstable. So again, the tube maker used whatever he could buy at the time, that was compatible with his manufacturing processes.
The specific shape of a getter, plate structure, or anything else, is only of interest now as an easy way to identify different products, some of which are assumed to be better than others, often in ways that the original makers wouldn't have dreamed of. It may be that 6L6s with "D" shaped getters (I'm making this up) "sound better" than tubes with washer-shaped getters. If so, it has nothing to do with the getter itself, only that at a certain time, one maker happened to use D-shaped getters and his girls were particularly adept at making good tubes. Whereas the competitor's girls used hand lotion that contaminated theirs. Or, more often than modern audiophiles will admit, there is no difference, but folklore is self-perpetuating (if you paid a lot for a tube or searched for years to find it, it always sounds better). And the differences between tubes must be visually obvious, so your friends will see that you're using the "better" version.
I recommend Robert Tomer's 1960 book "Getting the Most out of Vacuum Tubes" which I've been told is on the net somewhere, which discusses the tube characteristics that really matter, with no nonsense.
