In Reply to: RE: "AMPLIFIER DESIGNS FOR REDUCED IMD" posted by rage on November 20, 2021 at 05:36:02:
Feedback is a MUST with pentode outputs. Not only do they produce excessive IMD otherwise, their high anode impedance creates very poor damping. I can't tell you how much is needed in UL, but I typically use 6 dB to 12 dB with SE pentodes. Don't be afraid to use 6 dB or so in order to make it right. Get those measurement issues resolved first though. :)
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Follow Ups
- RE: "AMPLIFIER DESIGNS FOR REDUCED IMD" - Triode_Kingdom 11/20/2115:39:55 11/20/21 (18)
- RE: "AMPLIFIER DESIGNS FOR REDUCED IMD" - PakProtector 05:22:34 11/21/21 (17)
- RE: "AMPLIFIER DESIGNS FOR REDUCED IMD" - Triode_Kingdom 14:18:12 11/21/21 (5)
- RE: "AMPLIFIER DESIGNS FOR REDUCED IMD" - PakProtector 17:31:26 11/21/21 (4)
- RE: "AMPLIFIER DESIGNS FOR REDUCED IMD" - Triode_Kingdom 17:55:09 11/21/21 (3)
- RE: "AMPLIFIER DESIGNS FOR REDUCED IMD" - PakProtector 19:00:45 11/21/21 (2)
- RE: "AMPLIFIER DESIGNS FOR REDUCED IMD" - Triode_Kingdom 07:16:41 11/22/21 (1)
- RE: "AMPLIFIER DESIGNS FOR REDUCED IMD" - PakProtector 15:36:58 11/22/21 (0)
- RE: "AMPLIFIER DESIGNS FOR REDUCED IMD" - cellailuca 08:22:20 11/21/21 (10)
- RE: "AMPLIFIER DESIGNS FOR REDUCED IMD" - PakProtector 17:29:41 11/21/21 (8)
- RE: "AMPLIFIER DESIGNS FOR REDUCED IMD" - cellailuca 00:25:12 11/22/21 (7)
- RE: "AMPLIFIER DESIGNS FOR REDUCED IMD" - PakProtector 01:53:21 11/23/21 (6)
- That's the point! - cellailuca 04:23:45 11/23/21 (0)
- RE: "AMPLIFIER DESIGNS FOR REDUCED IMD" - sony6060 02:53:43 11/23/21 (4)
- 1% THD is Detectable by Most People - Triode_Kingdom 10:32:08 11/25/21 (2)
- RE: 1% THD is Detectable by Most People - sony6060 11:59:24 11/25/21 (1)
- RE: 1% THD is Detectable by Most People - Tre' 20:26:45 11/25/21 (0)
- RE: "AMPLIFIER DESIGNS FOR REDUCED IMD" - PakProtector 15:40:10 11/23/21 (0)
- Effects of IMD - Triode_Kingdom 14:07:06 11/21/21 (0)