What is an ultra-linear amplifier?
ULTRA-LINEAR OPERATION, also known as DISTRIBUTED LOAD OPERATION, is a term when applied to single-ended or push-pull vacuum tube audio amplifiers, that describes the particular output stage configuration whereby the Screen Grids (Grid 2) of Tetrodes, Pentodes or Beam Power Tubes are fed from a tapping in the output …
What is the difference between triode and pentode?
A triode tube has a control grid (signal in), a plate (signal out), and a cathode. A pentode adds two more components: a screen grid and a suppressor grid; these make the tube more efficient and increase power output.
What is ultra-linear speaker?
Ultra-linear electronic circuits are those used to couple a tetrode or pentode vacuum-tube (also called “electron-valve”) to a load (e.g. to a loudspeaker). ‘Ultra-linear’ is a special case of ‘distributed loading’; a circuit technique patented by Alan Blumlein in 1937 (Patent No.
What is Ultralinear mode?
In Ultralinear you have a combination of triode and pentode ( where the screen is fed a constant voltage and produces the most power) operation with a specific percentage of the plates output used for feedback through a tap from the primary winding of the output transformer.
What is triode connection?
connected as Triodes. 10. Beam forming plates are used instead of a suppressor grid. They work by forming a concentrated electron beam, which also prevents secondary emission electrons to travel from anode to screen grid.
What is an Ultralinear output transformer?
In short, an ultra-linear transformer is an audio output transformer intended for use in the patented ultra-linear circuit. In this circuit the transformer provides the output load for a pair of tubes but also provides negative feedback around the tube from the output to the input.
What is pentode valve?
A pentode is an electronic device having five active electrodes. The term most commonly applies to a three-grid amplifying vacuum tube (thermionic valve), which was invented by Gilles Holst and Bernhard D.H. Tellegen in 1926. The pentode is closely related to the beam tetrode.
What is a triode amplifier?
triode, electron tube consisting of three electrodes—cathode filament, anode plate, and control grid—mounted in an evacuated metal or glass container. It has been used as an amplifier for both audio and radio signals, as an oscillator, and in electronic circuits.
Is triode mode Class A?
Also, there is no such thing as a class A triode. Class A refers to how the tube is used. Any triode can be wired in class A or class B.
Can you use a pentode as a triode?
Sometimes manufacturers of pentodes also published triode connected curves and often they are used this way. Famous examples include: EF86 (extremely linear), EL34 (everybody knows it can power a decent triode SE or PP amp).
How does a pentode work?
Its function is to create a lower voltage region between the screen grid and the anode. It suppresses the secondary emission where high energy electrons hitting the anode at high speed have a tendency to bounce off. This effect causes a kink in the response curve of tetrode valves.
What does a pentode do?
The pentode can be used for almost all purposes for which vacuum tubes are used, including amplification, mixing, oscillation, and pulse generation, and in circuits for timing, control, and counting.
Which is better a triode or ultralinear AMP?
In these type amps, almost always the ultralinear mode will sound better than the triode because the pentode tube is in a circuit that makes compromises for the flexabilty. Philefreak ; very informative , I was not aware of that !
What was the patent for the Ultra Linear Screen?
Also US Patent 2218902 (22 October 1940). Blumlien’s Patent specified an optimum feedback tapping ratio being between 25 and 50% of plate output voltage to the Screen Grid, however he did not use either of the terms “Ultra-Linear” or “Distributed Load” in his Patent.
When was ultra linear operation of the Williamson Amplifier published?
Details are provided in their paper “Ultra-linear operation of the Williamson Amplifier” by Hafler and Keroes, published in the June 1952 edition of “Audio Engineering” magazine. It seems then that they had the last word, by improving Williamson’s design despite his dismissal of the concept..
What is the output impedance of an ultra linear amplifier?
Output impedance is similar to triodes, allowing minimal or zero negative loop feedback to be used. The ultra-linear amplifier concept is beautifully described by David Hafler and Herbert Keroes in their 1952 US Patent Application 2710312. The following extract is included for convenience: