Hi Mark,
Log pots are normally used for audio level adjustments. Linear pots are commonly used for tone control applications.
A dual linear pot will have sections that tend to track each other better. The taper is wrong for level changes.
SY, mine glows green. Do I have to change them??
😀
-Chris
Log pots are normally used for audio level adjustments. Linear pots are commonly used for tone control applications.
A dual linear pot will have sections that tend to track each other better. The taper is wrong for level changes.
SY, mine glows green. Do I have to change them??

-Chris
Depends on the situation. "Linear", when talking about pots, is not a term that implies "better". Linear refers to the fact that for every degree of revolution you will see you will see an equal change in the resistance.
For example, if you use a linear pot in a volume control, it will too sensitive (touchy) at one extreme, and insensitive (useless) at the other extreme.
Log pots have the resistance "scrunched up" more toward one end. This makes volume control "feel" right.
Tone controls and others, can be done with log or linear pots... all depends on the exactl type of circuit used.
😀
For example, if you use a linear pot in a volume control, it will too sensitive (touchy) at one extreme, and insensitive (useless) at the other extreme.
Log pots have the resistance "scrunched up" more toward one end. This makes volume control "feel" right.
Tone controls and others, can be done with log or linear pots... all depends on the exactl type of circuit used.
😀
Green causes a subtle but noticeable diminution of soundstage, a bit of compression in the upper midrange, and some loss of lower midrange liquidity. You should change that to red.
I just replaced them with the new white LED's. After correcting the current I immediately noticed a much cleaner presentation. It seems to show the true colour of the surrounding circuitry.
😀
😀
Two different opinions in 2 posts!
1 says go for linear pot, another says go for log!
I just want to adjust the volume - I'm not bothered about tone controls - I like to leave the music as it sounds!
Basically the plan for the pre-amp is
3 line inputs
volume control
2 line outputs for bi-amping
Gold connectors
silver wiring
LED power indicator
Exposed valves
powdercoated chassis (know a guy who powdercoats).
Keep it nice and simple 😀
1 says go for linear pot, another says go for log!
I just want to adjust the volume - I'm not bothered about tone controls - I like to leave the music as it sounds!
Basically the plan for the pre-amp is
3 line inputs
volume control
2 line outputs for bi-amping
Gold connectors
silver wiring
LED power indicator
Exposed valves
powdercoated chassis (know a guy who powdercoats).
Keep it nice and simple 😀
volume is about log.
Loose the silver wire... it is pure silliness. Silver plated is fine if and only if it has teflon insulation... teflon is good for soldering.
Loose the silver wire... it is pure silliness. Silver plated is fine if and only if it has teflon insulation... teflon is good for soldering.
Hi Mark,
No, we (poobah and I) agree. In a classic volume control application you need to use an audio log taper control. So for the purpose of what you are doing, log taper.
So what colour of LED's are you using?
-Chris
No, we (poobah and I) agree. In a classic volume control application you need to use an audio log taper control. So for the purpose of what you are doing, log taper.
So what colour of LED's are you using?

-Chris
silver wiring 😀
you can get it from www.homegrownaudio.com teflon coated too. i'm not sure of sources in your area.
LED- I like amber 😀 but soft blue is ok 😀
you can get it from www.homegrownaudio.com teflon coated too. i'm not sure of sources in your area.
LED- I like amber 😀 but soft blue is ok 😀
Poobah,
If you play with the current level, the sound will clear right up. Too high a current will reveal things with blinding clairity. Not for long if you go really high.
-Chris
If you play with the current level, the sound will clear right up. Too high a current will reveal things with blinding clairity. Not for long if you go really high.
-Chris
You know sometimes you can score a roll of use aerospace wire with teflon in salvege yards. Commited, teh cool thing abotu teflon is the insulation doesn't shrink back when soldering.
Why do they plate copper wire with siver? Silver oxide is conductive; when your crimping connections onto wires, like for an airplane or something, the theory goes that the connections will remain better longer considering corrosion and all.
You will be soldering, not crimping, so even the silver plating isn't needed... doesn't hurt.
Electrons like copper AND silver... they just like 5% (or so) more copper that's all!
Why do they plate copper wire with siver? Silver oxide is conductive; when your crimping connections onto wires, like for an airplane or something, the theory goes that the connections will remain better longer considering corrosion and all.
You will be soldering, not crimping, so even the silver plating isn't needed... doesn't hurt.
Electrons like copper AND silver... they just like 5% (or so) more copper that's all!
The main reason for plating Cu with Ag in Teflon-insulated wire is that the copper will degrade on its surface during extrusion. Teflon requires VERY high extrusion temperatures compared with PVC, polyethylene, or similar materials.
Re: Teflon wire.
If you have to buy it, don't. Just use normal wire in that case. If you can get it for the same price or lower, it might be cool to play with. It will not sound any different.
-Chris
If you have to buy it, don't. Just use normal wire in that case. If you can get it for the same price or lower, it might be cool to play with. It will not sound any different.
-Chris
Yeah I got this board I build... one of the pins on a bed of nails, to test an LED, got bent somehow... of course the LED is facing down... so I have little mirror glued in place and a push a button real quick quick to verify operation...
Took me about 50 boards before I realized the LED were going dark before I was releasing the button.

Took me about 50 boards before I realized the LED were going dark before I was releasing the button.

Ah stop confusing a "newbie" with all that LED crap 😛
But probably blue 😛
Right - silverplated teflon coated wire.
As fort the pot - is an "Alps blue 100K" available in both log and linear - I have one of these being sent to me and I have no idea which it is
Is the bottlehead design considered a good one? It seems nice and simple - just the power supply to work out...
But probably blue 😛
Right - silverplated teflon coated wire.
As fort the pot - is an "Alps blue 100K" available in both log and linear - I have one of these being sent to me and I have no idea which it is

Is the bottlehead design considered a good one? It seems nice and simple - just the power supply to work out...
anatech said:Re: Teflon wire.
If you have to buy it, don't. Just use normal wire in that case. If you can get it for the same price or lower, it might be cool to play with. It will not sound any different.
-Chris
Yeah - I just have normal wire about the place. Well it's something I can change when I get itchy fingers 😀
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