need a pickup tutorial

[mandomaybe]

I jus bought a new mandolin, and want to add a pickup. As I read posts, shop around, etc., I remember that years ago I installed a pickup in my Taylor guitar (easier to do than I had feared) and recalled that I had to mount a 9 v. battery inside. I don't see batteries mentioned in discussions of mando pickups, nor in ads that I read. I googled this subject to get info, but couldn't find out much. Probably should phrase my search better, but also thought I'd just ask here. Why do some pickups require batteries? By the way, I'm very happy with the sound of my Taylor plugged in, only replaced the battery a couple of times.
If an explanantion/tutorial is too lengthy to do here, maybe someone could just point me to info online. Thanks!

[Nevin]

Most acoutic instrument pickups use a piezo electric element to produce a signal. Electric guitars and the like use a magnetic pickup. The output of these differ in impedence. At one time almost all instrument amplifiers were deigned for magnetic pickup instruments. While they would amplify piezo systems they tended to sound pretty bad. Preamplifiers (preamp) most often were used to both boost the signal and make for better impedence matching. Many guitars have preamps mounted inside them and use batteries. This can be done on mandolins but it is more common to use external preams which run on batteries or wall current. However, there is now a large selection of acoustic instrumetn amplifiers available that don't require a pream for impedence matching.

[pops1]

The battery is for the preamp the the pickup needs to match with the PA. Mandolins are really to small to want to put a battery and preamp inside the instrument so we use an external preamp. The external preamps will use a battery or phantom power from the PA. Two of the popular pickkups are K&K and JJB. Preamps can be another decision there are several that are popular, but there are more opinions on preamps than pickups. I like the FireEye RedEye preamp, others will I am sure weigh in on what they like.

[mandomaybe]

thanks for the replies, and I've seen similar comments elsewhere online. What still confuses me, though, is that my guitar pickup does NOT have a preamp built-in that uses battery power; it is only a pickup (which i installed myself, so I know there is nothing else there).

[CES]

I know there are some electric guitar “active” pickups that require 9 volt power. Maybe your pickup is in this vein? I’ll readily admit that my knowledge on this subject is limited, as I only play in environments where a mic will suffice (primarily in church). I do have an LR Baggs Venue preamp that I use with guitar on occasion and like, but haven’t tried it with mandolin yet...

[pops1]

There are also preamps in the endpin for guitars. They have no volume and tone adjustments, but they are preamps just the same, and look like a longer endpin. While there may be other pickups than active electric guitar pickups that require a battery, I don't know of any piezo pickkups that require a battery.

[Tom Wright]

Pickups per se do not require preamps but piezos mostly include them now, with exception of simple disc or dot systems like the JJB contact pickups. It is primarily the under-saddle pickups that are installed in a bridge that tend to include a preamp. It may not be obvious that one is involved--for example, the Headway "Snake" has a tiny preamp that looks like part of the wire going to the pickup element. Others have it as part of the endpin jack.

Some electric guitar and bass players (mostly the latter) like a preamp in the instrument ("active" pickups), but the magnetic pickups themselves don't require it.

It is really handy, though, to have a volume control, at least, on one's instrument. Taylor used to sell a cable with built-in volume control, but the custom manufacture was too expensive and not enough people were buying it. I built a small box with a volume pot, male chassis-mount jack, and female output jack, that I can plug into my endpin jack.

Others use a volume pedal, or if a preamp is not present, the belt-clip K&K preamp is handy, with its treble, middle, bass, and volume controls.

[pops1]

My preamp has a volume boost that I can preset and just step on the button for on and off should I need it, which I seldom do. I always wanted and easier volume boost for solo's, but I started keeping the mandolin at solo level and playing extremely easy or slightly muted with a shirt sleeve if I chord. I seldom chord so not a problem and it works well. On the slim occasion I need more, I can step on the boost. Should the band get louder the boost gets me thru the song and I can turn up on the PA after that and have the same safety net. I like the least things in front of me that I can and a simple pre like the FireEye does it for me.

[Mandobart]

Whether or not you need a preamp (or DI) is mostly dependent on what you're plugging into for amplification. It's all about impedance matching. The reason undersaddle piezo pickups are more susceptible to the dreaded "piezo quack" than soundboard piezo's is the fact that they are always under strain due to the string tension on the saddle, which biases them toward saturation. Soundboard mounted piezo's such as K&K or JJB are under no strain except when actually playing the instrument. However, they will still sound better if you match their output impedance to the input device. Piezo disc systems absolutely DO need a preamp or DI under certain conditions.

Piezo's (whether undersaddle, undersoundboard, external contact, etc.) have an impedance in the megohm range. Mics and mag pickups are about 1000 x lower. Most all acoustic amps are made with an input impedance that matches the piezo (1 - 20 Megohm). Many PA mixers have channels in the kilohm range for mics and mags. I've found for my piezo-equipped instruments I don't need a preamp or DI when plugging in to an acoustic amp, but I usually do when plugging into a PA. There are many more choices for pre-amps/DI's than there are pickups. I've never had a decent preamp/DI hurt my sound even when used where its not needed. I have had poor sound quality when I didn't use a pre-amp/DI and needed it.

As posted earlier, mandolins and fiddles just don't have the space to mount a typical barn door type guitar preamp complete with battery. Even if you could fit a streamlined end-pin preamp inside them, changing the battery would be very difficult when you can't even get a finger let alone hand inside the soundbox. Also, I like to keep alkaline batteries, which can leak, far away from the actual instrument in an external preamp.

[mandroid]

Godin A8 is more what you are used to in an onboard preamp.
they have the 9v battery compartment, there to power the pre amp..

Line level signal then so you don't need a second preamp .. use a 1/4" TR instrument cord..

the in-bridge pickups are combined at a volume and tone control slider set .. part of the Preamp IC.

its a semi solid semi hollow bodied 8 string electric , without an acoustic soundhole..



many owners have posted revues , liking them ..