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Argus25 · 16th Feb 2019, 11:30 am

I think military rated components, valves, transistors and IC's do have some advantages.

To meet the contract specifications I think there was a lot more supervision & testing of the product during & after manufacture at the factory.

One example of this applying to IC's (though I'm sure the principle is the same for valves) is the difference between 54 series and 74 series logic IC's. They are essentially the same part, but many people who worked with them back in the 1970's reported that 1/100 new 74 series types were faulty. However, if one tries to find a new old stock 54 series IC that is faulty, good luck. I have been trying my whole life (as an ongoing experiment) have tested literally thousands of NOS 54 series IC's and I still can't find a single one faulty from new.

Also other mil spec parts (if genuine) transistors, capacitors, resistors are less likely to be DOA. For my projects using vintage parts, I often go for mil spec parts (if they are affordable).

I don't know if many of the valves out there such as ECC83's that are being said to be mil spec parts are genuine mil spec conformity, but if they were genuine NOS mil spec parts, you could probably quite sure they will be well made & working. Whether they "sound" any different (in an audio application) that is a whole other story.

16th Feb 2019, 11:30 am	#26
Argus25 No Longer a Member Join Date: Oct 2016 Location: Maroochydore, Queensland, Australia. Posts: 2,679	Re: "Audio" Valves I think military rated components, valves, transistors and IC's do have some advantages. To meet the contract specifications I think there was a lot more supervision & testing of the product during & after manufacture at the factory. One example of this applying to IC's (though I'm sure the principle is the same for valves) is the difference between 54 series and 74 series logic IC's. They are essentially the same part, but many people who worked with them back in the 1970's reported that 1/100 new 74 series types were faulty. However, if one tries to find a new old stock 54 series IC that is faulty, good luck. I have been trying my whole life (as an ongoing experiment) have tested literally thousands of NOS 54 series IC's and I still can't find a single one faulty from new. Also other mil spec parts (if genuine) transistors, capacitors, resistors are less likely to be DOA. For my projects using vintage parts, I often go for mil spec parts (if they are affordable). I don't know if many of the valves out there such as ECC83's that are being said to be mil spec parts are genuine mil spec conformity, but if they were genuine NOS mil spec parts, you could probably quite sure they will be well made & working. Whether they "sound" any different (in an audio application) that is a whole other story.