Thresholds & Opinions on Modern Carbon Comp Resistors

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Thresholds & Opinions on Modern Carbon Comp Resistors

Postby vez on Thu May 11, 2017 6:58 pm

In your opinion, what threshold(s) do you apply when replacing resistors? 5%,10%? Perhaps it depends on how its used?
What's your opinion of modern carbon comp resistors? Are they different from the old A&Be? And, are they worth it or should I just go with carbon film or even metal?
Thanks, Rick
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Re: Thresholds & Opinions on Modern Carbon Comp Resistors

Postby Unit_1 on Fri May 12, 2017 2:32 pm

I only use metal where really close tolerance is required, like in the 1 ohm resistor to ground for bias setting using Ohm's law. I built one amp with all metal resistors and it was kinda cold sounding compared to others I made.

I disliked it so much I replaced them all. Although I notice all tube stereos I've seen use metal, but then guitar amps are made to color the sound, where stereos are aiming for as close to original signal as possible. When you play an electric guitar without an amp, it becomes obvious why you need to color that sound!!!!!

I use carbon film for everything else for several reasons. CF have basically the same sound as CC but without the buzz and hum. CF has a very high tolerance to impulses (damn my brain is farting, I can't think of the right word? you know, when current goes up and down real quick, lol.... I hate getting old), CC drift in resistance with age and are prone to cracking eventually where CF do not.

And now Izzy is in my lap, he bites my hands when I type so I gotta go!!!! :highfive:
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Re: Thresholds & Opinions on Modern Carbon Comp Resistors

Postby vez on Fri May 12, 2017 3:46 pm

Unit_1 wrote:I only use metal where really close tolerance is required, like in the 1 ohm resistor to ground for bias setting using Ohm's law. I built one amp with all metal resistors and it was kinda cold sounding compared to others I made.

I disliked it so much I replaced them all. Although I notice all tube stereos I've seen use metal, but then guitar amps are made to color the sound, where stereos are aiming for as close to original signal as possible. When you play an electric guitar without an amp, it becomes obvious why you need to color that sound!!!!!

I use carbon film for everything else for several reasons. CF have basically the same sound as CC but without the buzz and hum. CF has a very high tolerance to impulses (damn my brain is farting, I can't think of the right word? you know, when current goes up and down real quick, lol.... I hate getting old), CC drift in resistance with age and are prone to cracking eventually where CF do not.

And now Izzy is in my lap, he bites my hands when I type so I gotta go!!!! :highfive:

Thanks Unit. How have you been lately? I havent been here for a long time.
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Re: Thresholds & Opinions on Modern Carbon Comp Resistors

Postby pdf64 on Fri May 12, 2017 6:49 pm

Have a read of http://www.geofex.com/Article_Folders/c ... oncomp.htm
My understanding is that CC cope much better with energy pulses than other types, hence they're still made / widely available.
When maintaining equipment fitted with them, I suggest that as a minimum they are replaced if their value has drifted enough to affect an operating point, or they're adding excessive noise into the signal path.
My band:-http://www.youtube.com/user/RedwingBand
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Re: Thresholds & Opinions on Modern Carbon Comp Resistors

Postby vez on Sat May 13, 2017 3:09 am

pdf64 wrote:Have a read of http://www.geofex.com/Article_Folders/c ... oncomp.htm
My understanding is that CC cope much better with energy pulses than other types, hence they're still made / widely available.
When maintaining equipment fitted with them, I suggest that as a minimum they are replaced if their value has drifted enough to affect an operating point, or they're adding excessive noise into the signal path.

Great read Pdf64, thank you.
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Re: Thresholds & Opinions on Modern Carbon Comp Resistors

Postby Unit_1 on Sat May 13, 2017 10:17 pm

vez wrote:
Unit_1 wrote:I only use metal where really close tolerance is required, like in the 1 ohm resistor to ground for bias setting using Ohm's law. I built one amp with all metal resistors and it was kinda cold sounding compared to others I made.

I disliked it so much I replaced them all. Although I notice all tube stereos I've seen use metal, but then guitar amps are made to color the sound, where stereos are aiming for as close to original signal as possible. When you play an electric guitar without an amp, it becomes obvious why you need to color that sound!!!!!

I use carbon film for everything else for several reasons. CF have basically the same sound as CC but without the buzz and hum. CF has a very high tolerance to impulses (damn my brain is farting, I can't think of the right word? you know, when current goes up and down real quick, lol.... I hate getting old), CC drift in resistance with age and are prone to cracking eventually where CF do not.

And now Izzy is in my lap, he bites my hands when I type so I gotta go!!!! :highfive:

Thanks Unit. How have you been lately? I havent been here for a long time.


Getting old has been challenging. I was taking more and more opioids for the arthritis pain and it was working less and less. Out of desperation, I bought some of the arthritis pain marijuana at ye olde dispensary (was only using for insomnia) and I'LL BE DAMNED IT ACTUALLY WORKS.

I couldn't believe it. :say_what: Not only was the pain just GONE in an instant, but the swelling went away and I have like 500% more freedom of movement in my right hand!!!! I could only close my hand down to where I could clasp a 3/4" diameter rod and not enough to keep it from sliding out. Now I can hold a pencil and hold it nice and tight!

It's a freakin' Miracle. Good Bye Opioids..... I no longer need them. Unless I get a cold. Pot doesn't do shit for a sore throat, lol...

current ripple. That's the word I was shooting for. Very high tolerance to current ripple. :thumbsup:

How's life been treating you Rick? :rawk:
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The ability to play/make music is a gift that not everyone gets. Those of us who have it should use it.

Asimov:Individual science fiction stories may seem as trivial as ever to the blinder critics and philosophers of today — but the core of science fiction, its essence, the concept around which it revolves, has become crucial to our salvation if we are to be saved at all.
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