Popping noise with LR Baggs Lyric + Ultrasound DI Plus

[jorge rodriguez]

Hi,

I was looking for a pickup to amplify my Martin guitar and I finally decided to try the LR Baggs Lyric, it's an internal microphone. I read goods reviews so I decided to give it a try.

I installed it this morning, plugged it in... seems to work... then I tried with an acoustic preamp that I already had, it's an Ultrasound DI Plus. When I added this, I get a continuous popping noise, it sounds kinda like a coffee machine when the coffee is ready...

I tried with and electric guitar amplifier, a Fender, and straight to the computer... both ways I get the horrible noise... so could it be some kind of incompatibility between the Lyric and the preamp? I don't know much about electronics, so any help would be nice...

Cheers

Jorge

[Mark Swanson]

Do you have any other guitars with pickups, electric or acoustic? Plug one of them into the preamp. I suspect something is wrong with the preamp, if it does that with another guitar that will tell you. If the Baggs mic only makes that noise with the preamp that is telling.

[jorge rodriguez]

Hi Mark,

Thanks for your reply.

Yes, I have tested the preamp with another guitar and there's no noise. The Lyric without the preamp works fine... so I'm afraid I can't use the Lyric with this preamp... Not good. Anyone knows why? Just out of curiosity...

Cheers

[Daryl Kosinski]

I will take a guess that both devices have digital amplifiers in them. Could be they use different sampling frequencies and your getting a weird beat frequency between the two.

[jorge rodriguez]

Hi Daryl,

Yes, the Lyric also has a bulit-in preamp. I just wanted to use the Ultrasound with it to equalize the sound a bit before it gets to the mixing desk and have a bit more control over the sound accessible to me if I play live. But to be honest I am an ignorant about "sampling frequencies"... Anyway I guess you are probably right. I sent a message to LR Baggs to ask if the Lyric is supposed to work with other preamps... we'll see.

Thanks!

Jorge

[David King]

Could it be that the Ultrasound DI plus is trying to send phantom power to the Lyric? 48V of dc voltage where it's not wanted could make just about anything or body sound like a pot of hot coffee.

[jorge rodriguez]

Thanks, David. No, I'm using battery in the Ultrasound, no phantom power.

[Daryl Kosinski]

Correction, the term I was looking for is clock frequency not sampling frequency. Pretty much the same thing. The digital age brings all sorts strange issues.

[jorge rodriguez]

Thanks Daryl.

LR Baggs replied saying that the Lyric should work with any preamp, and suggested checking cables and the battery in the preamp. The cables are fine, not sure about the battery. It looks strange to me that a bad battery could cause this problem, I would think it would just stop working, though. I will change it when I can, test it and let you all know, in case it helps anyone in the future.

[jorge rodriguez]

Well, I changed the battery in the preamp and the noise is gone. So aparently that was the problem. A silly thing, yes, but I would have thought that a weak battery would cause weak sound... but this kind of old motorbike noise...? Just like Daryl said, digital age brings strange issues...

Just posting in case it helps anyone...

Thanks everyone.

[Andrew Porter]

Low batteries often have enough juice to make a device work just not properly. My old pignose amp used to give killer distortion when the batteries were low. I put a rheostat in it to do it with new batteries.

[David King]

Even new 9Vs can give weird results. I bought some Lithium "Ultra" batteries once for a mission critical application and the simple act of pulling the connectors off the tops of them broke an internal connection making them intermittent. It's Duracell only for me from now on.