Are acoustic active pickups Hi or LoZ?

[joesixpack123]

Hi,

 

I use an active Fishman Deluxe SC piezo bridge pickup on my Larrivee acoustic guitar plugging directly into a mixer/PA system with line level (LoZ?) 1/4" inputs.

It seems to me that the output of an active pickup should match a line level input just fine. Is that not true? I'm inclined to try an LR Baggs just to see if it would improve the sound, which I find a little thin and hi-endy. Yeah, I use EQ to clean it up for whatever room I'm in.

 

Would using a direct box or preamp such as a LR Baggs paracoustic DI make any difference in sound quality as opposed to simply using EQ on the board and/or on the pickup itself?

 

Yeah, I should probably post in the acoustic gtr forum too. I'm more interested in this group's input. How do you pro-sound guys recommend handling getting good sounds from active ac gtr piezo pickups in a live situation?

 

-JS

[Scodiddly]

Does the pickup have a battery in it? If so, it should be OK with most inputs. I wouldn't expect an active pickup to have a line-level output, though - the designer would usually want it to be compatible with the inputs on guitar amps.

[prosigna]

"Line Level" and "Lo-z" are not exactly the same thing. A Shure SM-58 is Lo-z but no where near line level. Line Level designates the voltage of the signal. Hi-z and Lo-z designate the impedance.

[agedhorse]

The guitar world (generally) uses a somewhat different approach, in that to them, 50k is "lower" Z compared to 10k as higher Z in the pro audio world.

 

This allows for reasonable compatability, but loading can occur depending on the actual impedances of the equipment involved.

 

That's why most passive DI's are roughly 50k input impedance, and why sometimes, just plugging into a line input on a mixer doesn't produce the best (though usually pretty good) results.

 

The signal level is another thing, in that the acoustic guitar output will be around -10 to -30dBu or so and the line input of a mixer will usually want to see between -30 and +4dBu. There is some overlap so it will usually work, but not always.

 

These are some generalization, there are plenty of exceptions.

[joesixpack123]

Thanks, guys.

 

So, in my situation would you recommend a DI before the line level input?

 

-JS

[prosigna]

Some of the reasons (but not all the reasons) for a DI would be:

 

1. Impedance matching - I don't think you have this problem.

2. Phantom Power Protection - If you are using the 1/4" jacks you may not need this.

3. Interface with an XLR snake - If a 20' cable will get you to the board you won't need this.

 

The product you listed (paracoustic?) Is voiced for an acoustic guitar. The eq frequencies and curves are optimized for an acoustic guitar. The eq in the mixer is a generically voiced eq. The Paracoustic is more an effect than a regular DI. It will change you sound - good or bad is up to the listener.

[joesixpack123]

Great - thanks again. From what I'm reading it doesn't appear to be an impedance issue between the pickup and the mixer input. I'm just running an 18' guitar cable to the board.

 

It seems to me like I just need a better pickup (or different guitar) rather than a DI. I like the sound of the Dual Source/mini microphone pickups I've heard. I think I'd prefer to go that route rather than an outboard box.

 

-JS