The Type 45 Triode

The Type 45. This very early tube type dates to 1929 and makes the biggest and boldest 1.5 watts of single ended power known to man. This tube type kicks ass and is probably the ultimate triode from the standpoint of its superb fidelity combined with the sheer numbers of superb old stock tubes still available. And this tube has been reinvented, with a number of good quality current production tubes that continues to grow in variety, with mesh plates, globes, who knows what…the future is bright for the 45. This tube sounds wonderful and will be around for a long time. Most of the original 45 tubes out there are ST shaped, the globe ended production in the early 1930s. As seems typical with these ancient tube types, the globe shape does sound more open and transparent to me, while the ST shape has more "slam" and body. The 45 is certainly one of the best sounding tubes of all time and has become an audiophile classic. Tube data for the 45 can be found here.

45. A great assortment of early 1930s globe 45 tubes. Here we have one of Ken-Rad’s first tubes, the UX-245, a Majestic G45, Speed’s 145, an Arcturus blue glass No. 145, the amazing and super rare Perryman mesh plate PA245 and finally a Cunningham CX345. Notice the plates are slanted on the Majestic tube. This is the result of many decades of being stored on its side without moving; globe tubes have no support micas and gravity eventually takes it’s toll.

45. Mesh plate 45. The Perryman has a woven mesh plate and the modern Sophia "mesh" is actually a perforated plate rather than being woven. Both sound very good, but the Perryman is a little more magical and is probably the best sounding 45 ever made.

45. Mesh plate 45. A pair of modern 45 tubes, the Chinese-made Sophia mesh 45 and the Czech-made Emission Labs 45. Its hard to overstate the build quality of the Emission Lab tubes.

45. The 45 family tree.

45. ST 45 are great tubes, with a bit more authority than the globe shaped tubes. The RCA Cunningham engraved base tube on the right is an early 1930's tube.