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Old 24th November 2005, 09:48 AM   #1
Nordic is offline Nordic  South Africa
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Default Law fake pot

Can someone please draw for me a law fake pot....and how to connect it... I tried the following, but it does not seem to give the required effect.

Click the image to open in full size.

Please I am waiting with tools in hand to finish the case and I need to get the pots sorted first....
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Old 24th November 2005, 10:56 AM   #2
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What you drew there is correct. The pot must be linear type though and don't forget to take the input impedance of your amp into account with the shunt (10k in your case) resistor.
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Old 24th November 2005, 02:02 PM   #3
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Default Re: Law fake pot

Quote:
Originally posted by Nordic
Can someone please draw for me a law fake pot....
I don't understand why you wanna do this.
You will have much better results with a 10K log pot.
Unless you like your sound dark brown.
And noise.

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Old 24th November 2005, 02:24 PM   #4
Nordic is offline Nordic  South Africa
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If I had one... I would...
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Old 24th November 2005, 04:54 PM   #5
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Default Pots

Nordic,
If a 25K pot will work, I can mail a pair of matched log pots. There are a couple extra matched up pairs of 25K PEC mono pots in my closet.
I have never understood the reason for the fake log pots. They present a variable input impedance. This will make for differing frequency response as the pot is opened up. And contrary to opinion, there are log pots that track well.
The PEC pots are the best I have found. Beats the series attenuators tried, and all the conductive plastic tried over the last 20 years.
One neat feature is they have almost 360 degrees of rotation. This gives a very fine control at the low end of volume. On a normal pot most listening was in the first 90 degrees of rotation with every source. Now I use almost 180 degrees for phono, tuner, and digital. It make the hassle of mono pots much easier to deal with.

George
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Old 24th November 2005, 05:04 PM   #6
Nordic is offline Nordic  South Africa
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That would be sooooooo great.. I tried again today, best I could get was some10k linear ones.. I expect I won't like them much, busy with case, so can't test right now.

The reason I wanted to go the law fake, is because i can't get log pots.

But that was all I could get unless I order from RS components which is a little expensive for me
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Old 24th November 2005, 06:45 PM   #7
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10k lin are no good because if you law fake them you will load the source too much.
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Old 24th November 2005, 07:28 PM   #8
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Quote:
Originally posted by richie00boy
10k lin are no good because if you law fake them you will load the source too much.
I recommended 10k log.
You guys forget about law fake, it's not worth it.
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Old 25th November 2005, 01:06 AM   #9
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Hi

What is that law fake pot and what about the dark brown sound means, how to calculate that law fake pot

Thanks
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Old 25th November 2005, 08:24 AM   #10
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Law fake is where you connect a pot like in the top post and it changes the linear curve of the pot to a more logarithmic one like what you need for volume controls. Carlos thinks it sounds bad. I prefer it because it avoids any problems with wiper contact fluctuations losing the input bias path, and it makes it so much easier to use with the lower input impedance of todays amps.
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