klon silver question

[kirshman]

What is to be gained by switching from 10k lin to 10k log on the volume pot of the silver.  Is the sweep better?  I'm just not sure why that component switch is there?  Educate me please.

[Travis]

Whether or not it's "better" is subjective, but whether you choose linear or log won't change the sound at all. Linear will just reach unity gain earlier in the sweep

[Frank_NH]

I built a "silver" based upon the Aion Electronics "Refractor" PCB.  Yeah, sweep doesn't matter too much as long as you can dial in your sound level.  The gain pot seems to get heavier in a non-linear way, but again not a big problem.

Apparently, there really is no true "silver" Klon specs, and the mods from the standard schematic are relatively minor.  What probably makes the most difference in the character of the effect are the clipping diodes.  Experiment and find what you like.  I used the "magical" Russian D9Es and they sound fine, but honestly some BAT41s may work just as well.

Having said all the above, I really DO like the Klon.  It's a great overdrive and an even greater booster/buffer.  I feel the Klon buffer alone is an asset to my signal chain, but combined with a little boost from the overdrive circuit makes for a great "always-on" preamp.   

[Muadzin]

I never understood why so many people use a log volume pot in their layouts and builds. Any sweep that puts unity gain past 12:00 even into 14:00 territory is bad in my book. And log tends to do that most of the time. Is there some weird impedance thing that you get with linear, or any other kind of weird thing that everybody assumes is common knowledge so nobody bothers to explain?

[Travis]

No, but the unity volume will be different depending on your amp. Someone with a super loud amp may find log more usable because they have more control over unity

[induction]

Muadzin wrote

I never understood why so many people use a log volume pot in their layouts and builds. Any sweep that puts unity gain past 12:00 even into 14:00 territory is bad in my book. And log tends to do that most of the time. Is there some weird impedance thing that you get with linear, or any other kind of weird thing that everybody assumes is common knowledge so nobody bothers to explain?

It's a good question. Here's the answer:

The human ear has a logarithmic response to SPL (sound pressure level). In other words, an additive increase in perceived loudness requires a multiplicative increase in signal level. Thus a linear volume pot will create a logarithmic loudness profile. At low settings, the loudness will increase quickly, but at higher settings it will increase slowly. To counteract this, we use volume pots that increase the signal exponentially, so that the perceived loudness will increase linearly. This is why 'log taper' is also called 'audio taper'. (BTW, pitch increases logarithmically with frequency, so log pots are also good for tone controls.)

Another good question is why they are called 'log' pots when they actually have exponential response curves. I don't know the answer to that one. Some historical accident, I'm sure.

FWIW, where unity gain falls on the volume sweep depends on the circuit. If you want it at a particular setting, it usually takes only a very minor modification to the circuit to get it there.

[Frank_NH]

"If you want it at a particular setting, it usually takes only a very minor modification to the circuit to get it there. "

Quite true.  If you can't get to unity gain before or at 12, then look for a series resistor just before output pot and reduce it's value to taste.  If it is part of an output filter, then you'll also need to adjust the related capacitor's value so as not to alter the tone.

If that doesn't do it, then you may have to tack on a recovery gain stage to bump up the volume a few dB.