In Reply to: "Class A, literally means 'the best class' of amplifier." posted by FenderLover on August 16, 2016 at 20:56:01:
At one point I proposed "Linear Class A" to differentiate between "good practice" Class A and a design that merely didn't allow cutoff but in the end I changed my mind based on the text.
The Radio Handbook 14th Edition page 98 "......Such an amplifier is normally operated in the center of the grid-voltage plate-current transfer characteristic and gives an output wave-shape which is a substantial replica of the input wave-shape."
The Radio Handbook 38th Edition page 65 A Class A amplifier-- "...is one operated so that the wave shape of the output voltage is the same as that of the signal voltage applied to the grid."
Tremaine Audio-Cyclopedia 2nd Edition page 523 "The quiescent plate current is selected for a value in the most linear portion of the plate-current characteristic."
Page 543 "What is a class A amplifier? An amplifier in which the grid-bias voltage is set to approximately one-half the cutoff voltage to obtain linear operation."
Page 604 "When operating as a single tube, class a, little distortion exists because the grid signal operates in the most linear portion of the dynamic characteristic."
I am fully convinced that Class A is running the tube in "as linear a way as possible". That is, right in the middle of the "most linear part of the dynamic curve" and limiting the input signal to keep the tube's operation away from the non-linear cutoff and saturation regions and staying only in the linear part of the curve as shown in the graph above.
Tre'
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Follow Ups
- RE: "Class A, literally means 'the best class' of amplifier." - Tre' 21:26:18 08/16/16 (32)
- Would Class AB be closer to X or Y-axis of that graph? - FenderLover 06:15:24 08/17/16 (30)
- RE: Would Class AB be closer to X or Y-axis of that graph? - Tre' 10:08:33 08/17/16 (29)
- Thanks! I think... - FenderLover 08:02:43 08/18/16 (1)
- RE: Thanks! I think... - Tre' 09:41:35 08/18/16 (0)
- Ah, but that's the point ... - Naz 01:13:21 08/18/16 (26)
- RE: Ah, but that's the point ... - Tre' 09:28:21 08/18/16 (17)
- Too many variables ... - Naz 16:02:36 08/18/16 (16)
- RE: Too many variables ... - Tre' 17:25:19 08/18/16 (15)
- A Modern Misconception - Triode_Kingdom 08:30:00 08/19/16 (4)
- RE: A Modern Misconception - Tre' 08:47:45 08/19/16 (3)
- RE: A Modern Misconception - Triode_Kingdom 09:14:27 08/19/16 (2)
- RE: A Modern Misconception - PakProtector 04:00:57 08/28/16 (1)
- RE: A Modern Misconception - Tre' 16:36:31 08/28/16 (0)
- I don't disagree with the main aims of Class A ... - Naz 18:00:46 08/18/16 (9)
- RE: I don't disagree with the main aims of Class A ... - Tre' 18:05:36 08/18/16 (7)
- But you haven't answered my question ... - Naz 18:21:46 08/18/16 (6)
- RE: But you haven't answered my question ... - Tre' 19:02:33 08/18/16 (5)
- RE: But you haven't answered my question ... - Naz 19:29:06 08/18/16 (4)
- RE: But you haven't answered my question ... - Tre' 08:45:16 08/19/16 (3)
- Tube curves and Class A - Naz 14:12:59 08/19/16 (2)
- Operating condition vs. bias point. - Tre' 09:21:27 08/20/16 (1)
- We are saying the same thing except for one point ... - Naz 14:31:31 08/20/16 (0)
- +1 (nt) - Steve O 18:04:43 08/18/16 (0)
- When is a V8 a V6? - Triode_Kingdom 07:09:18 08/18/16 (6)
- RE: When is a V8 a V6? - Naz 17:26:17 08/18/16 (0)
- RE: When is a V8 a V6? - Steve O 09:49:20 08/18/16 (4)
- RE: When is a V8 a V6? - PakProtector 13:12:05 08/18/16 (0)
- definitions - Tre' 12:37:29 08/18/16 (0)
- RE: When is a V8 a V6? - Triode_Kingdom 10:15:24 08/18/16 (1)
- intent of "Class A" That is my bigger point - Tre' 11:23:34 08/18/16 (0)
- RE: Ah, but that's the point ... - dave slagle 06:30:58 08/18/16 (0)
- Tre, I'll take Howard Tremaine for 500...what is quiescent?~nT - Cleantimestream 02:36:16 08/17/16 (0)