That's a very interesting observation and info – at least, it interests me very much.
Can any one suggest why is it so from the technical aspect?
Generally, this was explained by less self-inductance for carbon comp: so the signal current flow with minor impedance at high frequency.
About their sound quality, another my recently personal idea, is the following:
- due to the above weak auto-inductance, the hf noise originates from power supply comes well discharged versus the gnd point, so the amp circuit is no much sensible to this noisy.
Francesco.
Hugo, IMHO it's not the subjectivism per se that is the problem. I think the real problem is when someone is trying to push their own subjective assessment down other people's throats.
The problem I see is when people attempt to pass their subjective assessment off as something more than that. In other words, when they insist that their subjective experience is inherently an unerring reflection of some objective reality, i.e. that any subjective perception of a difference must be the result of some actual audible difference.
That's the problem.
se
Well, experience show us that pots do have a characteristic sound, depending on what they are made of, and how they are put together, i.e. engineering tradeoffs. Therefore, some pots that have no easily measurable problem, stlll can sound marginal.
Other pots will actually distort in some way, in certain settings, if they are used in a slightly unconventional way, such as a 'loaded linear' configuration, in order to get a pseudo-audio taper from a linear pot, as Dick Burwin suggested to Mark Levinson; as a rheostat, like PMA wants to do, etc. etc.
Some pots are also inductive, other pots are noisy, especially when changing the setting, and most have a modulation noise that is signal sensitive, and MANY dual pots are lousy trackers.
Most here didn't realize all this, did they? ;-)
Other pots will actually distort in some way, in certain settings, if they are used in a slightly unconventional way, such as a 'loaded linear' configuration, in order to get a pseudo-audio taper from a linear pot, as Dick Burwin suggested to Mark Levinson; as a rheostat, like PMA wants to do, etc. etc.
Some pots are also inductive, other pots are noisy, especially when changing the setting, and most have a modulation noise that is signal sensitive, and MANY dual pots are lousy trackers.
Most here didn't realize all this, did they? ;-)
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Well said. The other problem I think is that when I spout my subjective opinion. Someone comes with some kind of objective reality that they think proves that my subjective opinion is not valid. For instance: If I prefer listening to records instead of CD's. Someone informs me that this is not correct for me to do. Because CD's have higher signal to noise ratio's. And so on and so forth.The problem I see is when people attempt to pass their subjective assessment off as something more than that. In other words, when they insist that their subjective experience is inherently an unerring reflection of some objective reality, i.e. that any subjective perception of a difference must be the result of some actual audible difference.
What do you think of the lightspeed "pot" John?. I was not interested until an audio friend of mine actually tried it and thought it was very very good. So now I shall investigate it as well.
Well said. The other problem I think is that when I spout my subjective opinion. Someone comes with some kind of objective reality that they think proves that my subjective opinion is not valid. For instance: If I prefer listening to records instead of CD's. Someone informs me that this is not correct for me to do. Because CD's have higher signal to noise ratio's. And so on and so forth.
Yeah, that's the flip side.
As long as all someone's doing is simply relating their subjective experience or subjective preference, they shouldn't get any grief from anyone.
se
(trying to get back on topic)
john & demian (and others):
what characteristics should us amateurs seeking higher performance results look for in choosing a "good" pot for a volume control?
btw, i am assuming we are doing some sort of signal attenuation with the pot, versus what charles (and maybe others) are doing for volume control.
mlloyd1
john & demian (and others):
what characteristics should us amateurs seeking higher performance results look for in choosing a "good" pot for a volume control?
btw, i am assuming we are doing some sort of signal attenuation with the pot, versus what charles (and maybe others) are doing for volume control.
mlloyd1
Well, experience show us that pots do have a characteristic sound, depending on what they are made of, and how they are put together, i.e. engineering tradeoffs ...
Contrary to some others opinions, I consider cermet pots to sound seriously better than conductive plastic - from personal listening.
Anyone actually also tried cermet critically?
The Vishay cermet is my favorite - it sounds (to me) just like a two resistor attenuator. But it's low end tracking is hopeless.
Regards, Allen
Anyone actually also tried cermet critically?
The Vishay cermet is my favorite - it sounds (to me) just like a two resistor attenuator. But it's low end tracking is hopeless.
Regards, Allen
Contrary to some others opinions, I consider cermet pots to sound seriously better than conductive plastic - from personal listening.
Anyone actually also tried cermet critically?
The Vishay cermet is my favorite - it sounds (to me) just like a two resistor attenuator. But it's low end tracking is hopeless.
Regards, Allen
I have never tried them Allen. Any recommendations on a specific unit? I might investigate this.
I not want persuade nobody, but if each experiences is judges only subjective and not objective, then because universally was acceipt that 2A3 is more musical than 6AS7 ?, or that 2A3 mono-plate is better than bi-plate?
Because any makers utilized Dale resistors rather unknow resistors?
I not discover that electrolytic or film caps have proper sound at the end.
If we can spech about its ok, if not no problem, i will go forward to my perceptive sensation. 😀
Francesco.
Because any makers utilized Dale resistors rather unknow resistors?
I not discover that electrolytic or film caps have proper sound at the end.
If we can spech about its ok, if not no problem, i will go forward to my perceptive sensation. 😀
Francesco.
I use a 100k Black Alps which has some dc flowing through the wiper, I know this is supposed to be bad but it sounds better than with an extra cap and res. Now after a year I am worried that I maybe shortening the life of the pot. Anyone know about this particular pot?
Subjective impressions are often at least as valuable as objective ones. Even with tubes, you can measure differences due to manufacture, even if they have the same tube number. I can prove this.
Subjective impressions are often at least as valuable as objective ones. Even with tubes, you can measure differences due to manufacture, even if they have the same tube number. I can prove this.
Thanks, John.
Sometime we can hear differences in sound, but it's more difficult to prove it or at least it is impossible to find differences by electrical measurement.
Not for this reason, people can define this fact as "subjective"
Francesco
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Subjective impressions are often at least as valuable as objective ones. Even with tubes, you can measure differences due to manufacture, even if they have the same tube number. I can prove this.
What type of tests that can reveal - audio attenuator quality ( Assuming Pots are no longer as good as resistor attenuators due to wiper or contact resistance variation issues) ? or whether Precision Bulk foil type resistors perform better as an attenuator than say Metal film resistor with 1% precision?
Kannan
What type of tests that can reveal - audio attenuator quality ( Assuming Pots are no longer as good as resistor attenuators due to wiper or contact resistance variation issues) ? or whether Precision Bulk foil type resistors perform better as an attenuator than say Metal film resistor with 1% precision?
Kannan
Listening maybe 😀
Contrary to some others opinions, I consider cermet pots to sound seriously better than conductive plastic - from personal listening.
Anyone actually also tried cermet critically?
The Vishay cermet is my favorite - it sounds (to me) just like a two resistor attenuator. But it's low end tracking is hopeless.
Regards, Allen
I have never tried them Allen. Any recommendations on a specific unit? I might investigate this.
Are we talking about a small white double linear one with short shaft and terrible L/R balance at start of rotation? It would not give any signal on one channel at medium whisper level actually! After kicking off was OK for balance though. I used that little thing back in the early 90s, law faked with Vishay's lowest PPM resistors of the time. I got it from a guy named Russ Andrews from Cumbria UK. Was a TT tweaking guy. I don't seem to can find it easily so to take a pic, I am not sure I still got it even, maybe it finally gave up the ghost, but I found its paper from Russ! If it is the same, yes I remember it as the most transparent pot I ever got in my system back then. The bad functionality broke my nerves in the end. After both channels would kick in (grrr!) then it would climb up fast even with 20:1 law fake. I remember that when I substituted it with Alps blue, and then Bourns blue, I could finally control my volume but they were thick as mud in comparison. Irony, and was costly too.😀
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Cermet may sound quite good at a given setting and may be fine for a trim pot. However as a volume control they can be noisy in operation and wear faster.
I have found that the Vishay metal foil trimmers are the best sounding to me. The Vishay 1280G was the best value of the options. I even figured out how to make it a front panel control- but 20 turns does not make a good volume control.
I have found that the Vishay metal foil trimmers are the best sounding to me. The Vishay 1280G was the best value of the options. I even figured out how to make it a front panel control- but 20 turns does not make a good volume control.
Cermet may sound quite good at a given setting and may be fine for a trim pot. However as a volume control they can be noisy in operation and wear faster.
I have found that the Vishay metal foil trimmers are the best sounding to me. The Vishay 1280G was the best value of the options. I even figured out how to make it a front panel control- but 20 turns does not make a good volume control.
Have you compared this Vishay Vs. Spectrol and Bourns trimpot, also?
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