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Old Yesterday, 10:44 PM   #1
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Join Date: Jun 2011
Default Is it that impossible?

2015 and the signal still goes through a pot for volume controlling in almost all analog circuits.

How god is this fot the SQ is a sensitive question, but people pay up to $240 for a Khozmo, Dact; Alps or you name it. Those DLR guys swear to gods and devils, it is the best they have heard.

Is that really needed? Why can't we do this way? Or how can we do it? A Volume Controlling Buffer.
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Old Yesterday, 11:06 PM   #2
OllBoll is offline OllBoll  Sweden
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Quote:
Originally Posted by Nosian View Post
2015 and the signal still goes through a pot for volume controlling in almost all analog circuits.

How god is this fot the SQ is a sensitive question, but people pay up to for a Khozmo, Dact; Alps or you name it. Those DLR guys swear to gods and devils, it is the best they have heard.

Is that really needed? Why can't we do this way? Or how can we do it? A Volume Controlling Buffer.
Which pretty much is what the B1 is.

An easier option if you have a digital source is to use digital volume management. As long as you can ensure that your gain structure is decent then it performs better, is easier and far more cheap =)
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Old Yesterday, 11:33 PM   #3
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Of course I have looked at the legendary B1, but it is still there! The signal goes through the pot, which I (and many others) don't want.

Time for the B2?
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Old Yesterday, 11:58 PM   #4
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In the case of the B1 I was looking for neutrality. The LDR designs (including
my own) generate significant 2nd and/or 3rd harmonic. Nothing wrong with
that if that's what you want.

You seem to have an a priori objection to a pot, perhaps because you
don't trust the wiper.

I deal with that issue by using good sealed pots and by having the wiper see
a high impedance load.

Honestly, I don't have an interest in pursuing the volume control thing further -
too many power amps remain unbuilt.

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Old Today, 12:15 AM   #5
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Thank you Mr. Pass for looking in. I love the concept of B1.

And what means "using good sealed pots and by having the wiper see a high impedance load" how? any explanation please?

Good luck with power.
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Old Today, 12:16 AM   #6
rayma is offline rayma  United States
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Location: Upper midwest
Quote:
Originally Posted by Nosian View Post
2015 and the signal still goes through a pot for volume controlling Why can't we do this way?
In most circuits, the analog of the signal is a voltage. A voltage attenuator requires a series resistance as well as a shunt resistance.
Both resistances are equally important. The shunt resistance is not less critical because the idea that the signal "doesn't go through it" is wrong.
The input characteristics of the following circuit are very important, since they load the attenuator and change its performance.

Switched high quality resistors are much better than any pot for analog volume control.

Last edited by rayma; Today at 12:30 AM.
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Old Today, 12:57 AM   #7
Bigun is offline Bigun  Canada
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If you just move your chair, nearer and further from the speakers, maybe you don't need any volume control
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