6V6
Encyclopedia
Tetrode
A tetrode is an electronic device having four active electrodes. The term most commonly applies to a two-grid vacuum tube. It has the three electrodes of a triode and an additional screen grid which significantly changes its behaviour.-Control grid:...
, introduced by Radio Corporation of America RCA
RCA
RCA Corporation, founded as the Radio Corporation of America, was an American electronics company in existence from 1919 to 1986. The RCA trademark is currently owned by the French conglomerate Technicolor SA through RCA Trademark Management S.A., a company owned by Technicolor...
United States in late 1937, and still in use in niche applications.
Similar to its predecessor the 6L6
6L6
6L6 is the designator for a vacuum tube introduced by Radio Corporation of America in July 1936. At the time Philips had already developed and patented power pentode designs, which were fast replacing power triodes due to their greater efficiency...
, the 6V6 was far more widely used. While the 6L6 was an excellent tube, it was not suitable for use in consumer electronic devices of the time because it required a lot of input power and hence a large, hot, and expensive power supply, and generated far more output power than required, especially in a distortion
Distortion
A distortion is the alteration of the original shape of an object, image, sound, waveform or other form of information or representation. Distortion is usually unwanted, and often many methods are employed to minimize it in practice...
-reducing push-pull pair
Push-pull output
A push–pull output is a type of electronic circuit that can drive either a positive or a negative current into a load. Push–pull outputs are present in TTL and CMOS digital logic circuits and in some types of amplifiers, and are usually realized as a complementary pair of transistors, one...
. With the introduction of the lower-powered 6V6, which required only half the heater power of the 6L6, the beam-power tetrode became a usable technology for the home, and became common in the audio output stage of radio
Radio
Radio is the transmission of signals through free space by modulation of electromagnetic waves with frequencies below those of visible light. Electromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of space...
s and audio amplifiers where power pentodes such as the 6F6 had previously been used. The 6V6 required less heater power and produced less distortion than the 6F6, while still offering higher output in both single-ended and push-pull configurations.
In an audio output stage, a single 6V6 can be used to produce about 3W RMS
RMS
-Science and technology:* Root mean square, a concept encapsulating the "average", in some sense, of a quantity. Frequently encountered in statistics, the physical sciences and electronics...
, and a push-pull pair about 10-12W with the higher power output requiring an expensive grain-oriented output transformer.
History
The 6V6 was introduced in both metal and shouldered glass tubes. RCA was promoting the superiority of its metal tube designs in the second half of the 1930s, and this tube, having been introduced during that period, was produced in large quantities in this format. Other tube manufacturers also produced the 6V6 in glass tubes, which were commonly found in radios not made by RCA. By 1940 the 6V6 was mostly being produced in a smaller "GT" glass envelope, and later the 6V6GTA was introduced which had a controlled warm-up period.Current use
Generally 6V6 tubes are sturdy and can be run beyond their published specifications (the 6P6S, which has poor tolerance for out-of-spec operation versus most American and West European-made 6V6 variants, is an exception). Because of this, the 6V6 became very popular for use in musical instrument amplifierInstrument amplifier
An instrument amplifier is an electronic amplifier that converts the often barely audible or purely electronic signal from musical instruments such as an electric guitar, an electric bass, or an electric keyboard into an electronic signal capable of driving a loudspeaker that can be heard by the...
s. This market allows Chinese
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
, Slovakia
Slovakia
The Slovak Republic is a landlocked state in Central Europe. It has a population of over five million and an area of about . Slovakia is bordered by the Czech Republic and Austria to the west, Poland to the north, Ukraine to the east and Hungary to the south...
n and Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
n tube factories to keep the 6V6 in production to this day. It is very often used in guitar amplifiers, such as the Fender Deluxe Reverb
Fender Deluxe Reverb
The Fender Deluxe Reverb is a guitar amplifier made originally by Fender Musical Instruments, and now by Fender. The Deluxe Reverb is a 22-watt tube amplifier , powered by a pair of 7408/6V6GT power tubes, one GZ34/5AR4 rectifier tube, four 7025/12AX7 preamp tubes, and two 6201/12AT7 tubes driving...
, the Fender Super Champ XD, or the tweed Fender Champ.
Similar tubes
A similar tube is 6AQ56AQ5
The 6AQ5 is a miniature 7-pin output beam tetrode. Ratings are virtually identical to the 6V6 at 250V and was commonly used as an output audio amplifier in tube TVs and radios. Also known under Mullard-Philips tube designation EL90...
, which has similar specifications to the 6V6GT, but in a miniature glass shell with a 7 pin base (this base being known in the UK as B7G
Tube socket
Tube sockets are electrical sockets into which vacuum tubes can be plugged, holding them in place and providing terminals, which can be soldered into the circuit, for each of the pins. Sockets are designed to allow tubes to be plugged in in only one orientation...
), and the 7408 as well as the Soviet-produced 6P1P
6P1P
The 6P1P is a Soviet-made miniature 9-pin beam tetrode vacuum tube with ratings similar to the 6AQ5, EL90 and the 6V6. Because of a different pinout than an 6AQ5/EL90, it cannot be used as a plug-in replacement for these types, however, it will work in the same circuit with component values...
, which is essentially the same as 6AQ5, but has a 9-pin base. Also with a 9 pin base (UK B9A
Tube socket
Tube sockets are electrical sockets into which vacuum tubes can be plugged, holding them in place and providing terminals, which can be soldered into the circuit, for each of the pins. Sockets are designed to allow tubes to be plugged in in only one orientation...
) was the 6BW6, an exact miniature equivalent of the 6V6. The 12AB5 is a 9 pin miniature variant with a 12V heater, suitable for automotive radio applications.
In the Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
a version of the 6V6GT was produced since the late 1940s which appears to be a close copy of the 1940s Sylvania-issue 6V6GT - initially under its American designation (in both Latin and Cyrillic lettering), but later, after USSR had adopted its own system of designations
Russian tube designations
- Receiver tubes :In the 1950s a 5-element system was adopted in the Soviet Union for designating receiver vacuum tubes....
, the tube was being marked 6P6S (6П6С in Cyrillic.)
See also
- List of vacuum tubes
- KT61
- KT66KT66The KT66 is a beam tetrode/kinkless tetrode vacuum tube for audio amplification.KT66 is the designator for a vacuum tube introduced by Marconi-Osram Valve Co. Ltd. of Britain in 1937....
- KT77
- KT88KT88The KT88 is a beam tetrode/kinkless tetrode vacuum tube for audio amplification.- Features :The KT88 fits a standard eight-pin octal socket and has similar pinout and applications as the 6L6 and EL34. Specifically designed for audio amplification, the KT88 has similar ratings to the American 6550...
- 6L66L66L6 is the designator for a vacuum tube introduced by Radio Corporation of America in July 1936. At the time Philips had already developed and patented power pentode designs, which were fast replacing power triodes due to their greater efficiency...
- 6CA7/EL34
- 6CM6
- 6DQ5
- 6DQ6
- 807807/ATS25The 807 is a beam tetrode vacuum tube, widely used in AF and RF power amplifier applications. The 807 is one of the most ubiquitous and recognizable of thermionic valves/vacuum tubes.-Audio uses:...
- Beam tetrodeBeam tetrodeA beam tetrode is a type of vacuum tube specially designed to produce greater output power than a similar pentode...
- Several tube data sheets