Here's a shot of a little problem-solver that came today, the Lehle DC Filter. So what's it for, and how does it do? Read on.
You know how some vintage and vintage-style amps are more sensitive to clicks and pops from pedals, effects, and switchers? And some aren't? Turns out there's a thing called a DC Offset that can be present in the audio signal of an effect, or a switch box, or at the input of an amp.
I don't have the technical expertise to describe why this is, I just know it's a thing that happens. Evidently it has something to do with where the signal containing the unwanted DC's waveform crosses the zero point as the wave alternates.
Back to the box, and the need for it in my rig: My DG30 is a vintage-style amp that's always been a bit sensitive to switching noises, especially coming from true bypass pedals and such. Some gear made more noise than other gear when playing the DG30.
We're talking about a mild pop or click when hitting a switch.
It's always been livable, but when the amp was connected to my pedalboard along with other amps via switch boxes or transformers (even with its signal ground lifted), the noise was a little more objectionable, and seemed to cause similar noises in the switching of the other amps that were connected, whether one or two more amps.
Well, when in the studio with headphones on, and switching pedals on and off, or switching between amps, I like to minimize any noises from switching. When I got the Lehle 1at3 SGoS switcher, to take my pedalboard signal to three amps, I asked Lehle's customer service guy, Joki, if there was a fix for this. He asked me what was happening, and I explained it as best I could, and he said he thought it was a DC offset somewhere, and helped me narrow it down to the DG30. Yes, he said, there was a product Lehle makes to make that go away.
Great, I ordered it; the Lehle DC Filter. It's a very small, completely passive (no power needed) box that you plug between the output of your switcher and the input of the amp, in this case (there could also be a DC offset elsewhere in the chain, and in that case, you'd put the filter somewhere else in the chain). And it's wonderfully inexpensive.
The claim was that if a DC offset existed, this would solve it. Moreover, that it's transparent.
I'm happy to report that both are true. I now have no switching noises whatsoever. And I can't tell this thing is in the signal chain. The DG sounds just as good as it always did. I'll do more critical listening at some point, too, but so far, I'm not hearing any change in the tone, or artifacts such as noise, hum, etc.
The thing works. At this price, every studio should have one of these around to solve these kinds of problems. It works with unbalanced, and balanced, signals, too. So an outboard rackmount signal processor will work with it, etc. And it's so tiny, it couldn't be more convenient to put in a gig bag and take along just in case! I think it'd be especially necessary for players who rent backlines on tours and never know what they're going to run into for amplification.
Obviously, if the problem you have is a broken switch, or some other noise-inducing thing, this isn't going to solve it. It's strictly a DC Filter.
Highly recommended!
You know how some vintage and vintage-style amps are more sensitive to clicks and pops from pedals, effects, and switchers? And some aren't? Turns out there's a thing called a DC Offset that can be present in the audio signal of an effect, or a switch box, or at the input of an amp.
I don't have the technical expertise to describe why this is, I just know it's a thing that happens. Evidently it has something to do with where the signal containing the unwanted DC's waveform crosses the zero point as the wave alternates.
Back to the box, and the need for it in my rig: My DG30 is a vintage-style amp that's always been a bit sensitive to switching noises, especially coming from true bypass pedals and such. Some gear made more noise than other gear when playing the DG30.
We're talking about a mild pop or click when hitting a switch.
It's always been livable, but when the amp was connected to my pedalboard along with other amps via switch boxes or transformers (even with its signal ground lifted), the noise was a little more objectionable, and seemed to cause similar noises in the switching of the other amps that were connected, whether one or two more amps.
Well, when in the studio with headphones on, and switching pedals on and off, or switching between amps, I like to minimize any noises from switching. When I got the Lehle 1at3 SGoS switcher, to take my pedalboard signal to three amps, I asked Lehle's customer service guy, Joki, if there was a fix for this. He asked me what was happening, and I explained it as best I could, and he said he thought it was a DC offset somewhere, and helped me narrow it down to the DG30. Yes, he said, there was a product Lehle makes to make that go away.
Great, I ordered it; the Lehle DC Filter. It's a very small, completely passive (no power needed) box that you plug between the output of your switcher and the input of the amp, in this case (there could also be a DC offset elsewhere in the chain, and in that case, you'd put the filter somewhere else in the chain). And it's wonderfully inexpensive.
The claim was that if a DC offset existed, this would solve it. Moreover, that it's transparent.
I'm happy to report that both are true. I now have no switching noises whatsoever. And I can't tell this thing is in the signal chain. The DG sounds just as good as it always did. I'll do more critical listening at some point, too, but so far, I'm not hearing any change in the tone, or artifacts such as noise, hum, etc.
The thing works. At this price, every studio should have one of these around to solve these kinds of problems. It works with unbalanced, and balanced, signals, too. So an outboard rackmount signal processor will work with it, etc. And it's so tiny, it couldn't be more convenient to put in a gig bag and take along just in case! I think it'd be especially necessary for players who rent backlines on tours and never know what they're going to run into for amplification.
Obviously, if the problem you have is a broken switch, or some other noise-inducing thing, this isn't going to solve it. It's strictly a DC Filter.
Highly recommended!
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