Lampy Lampy Lampy

[Burning]

pisałem o RCA, były ich 3 rodzaje:
RCA 12AX7:

RCA ('Radio Corporation of America') is the most well known company that produced tubes in the USA, and their 12AX7s are among the most popular NOS and vintage tubes looked for by musicians and audiophiles. RCA also produced some of the earliest 12AX7s and made many innovations in tube manufacturing that were copied by other companies. Many RCA tubes came standard in vintage Fender amps and are considered a big part of that 'Fender' sound. Some RCA tubes are popular with audiophiles, especially the 5751 tubes like the RCA Command Series and some RCA Blackplate 12AX7s. You can break down RCA 12AX7 tubes into three common types:

Gray plate 17mm 12AX7:

These tubes were produced from the late 50's to early 60's. They have 17mm ribbed ladder plates and a horseshoe, 'D,' or halo getter. Earlier versions will have the horeshoe/D getter, and are worth more. These tubes have that classic 'RCA' sound in a guitar amp: a bell-like clean tone and a 'Phat' somewhat gritty overdrive. They are popular with Fender users and other people interested in an early rock and blues sound. A very sweet sounding tube. Keep an eye out for the rare, low noise version of this tube.... the 7025 Gray Long Plate. I don't come across these too often. (They are much less common than the 14mm RCA 7025 Short Plate.) Also look for Baldwin or Lowrey branded RCA long plate 12AX7s. These were specially selected low noise tubes made for organs and represent high quality RCA tubes. They were once a bargain, but prices have been going up recently as more people discover these tubes.

RCA Gray plate 14mm 12AX7:

The most common RCA 12AX7 type, the Gray 14mm short plate was produced from the mid-60's onward and came standard in many Fender and other American amps of the era. They will have 14mm gray ribbed plates and a halo getter. These tubes have a similar sound to the RCA Grayplate 12AX7 ... bell-like clean tone and gritty overdrive. They are a bit 'less open' than their long plate counterparts, but still fine tubes. Look out for the 7025 low noise version of this tube... many people consider it to be superior, with slightly different sonics. RCA short plates can be had at a reasonable price, although can be somewhat costly if 'perfect' NOS.

RCA 17mm Black plate 12AX7:

This is the first RCA 12AX7s ever produced and it is one of the most sought after 12AX7 black plates. They were manufactured starting in the early 1950's and can be identified by their 17mm dull ribbed Black plates and a horseshoe or square getter. Earlier versions have the square getter. These are highly regarded tubes by audiophiles and guitarists, and can command high prices, especially if they are NOS . Like all black plates, these have a more complex, harmonic sound similar to some European tubes. The clean tone is very colorful and balanced and the overdrive is harmonic and very saturated in a guitar amp, with a touch of high-end roll off. Audiophiles who are looking for a warm yet balanced tube will probably like the RCA 12AX7 as well. One of my favorite black plate 12AX7s.