Piezo Bridge Pickup - best way to wire?

Gubna · #1 06-10-2008, 02:45 PM

I recently purchased one of these and installed it on my bass, but haven't wired it up yet. I want to get some advice on it. Did a search and didn't quite find my answers...

http://cgi.ebay.com/5-string-Bass-Br...QQcmdZViewItem

So, what would be the best way to wire this up? Currently my bass (pictured below) is wired much like a standard P bass (only with the MM style pick up), one volume, one tone.

Could I just add another jack and wire it directly ?

Or is there a way to wire it to the current set up?

Mushroo · #2 06-10-2008, 02:52 PM

Hello Gubna,
An active onboard preamp is definitely recommended if you want to blend the piezo with your magnetic pickup at the bass end of things. I would recommend this approach for maximum versatility and ease of use (it's all at your fingertips) rather than wiring a 2nd jack. There are several manufacturers for this kind of thing, off the top of my head I'm thinking Bartolini, Rick Turner, etc.

If you decide to wire 2 jacks (or 1 stereo jack), you can run the piezo passively. You may or may not be happy with the sound of an unbuffered piezo. Send the piezo and magnetic pickups through separate channels of the amp/preamp and blend them together. Certain amp manufacturers, such as Acoustic Image, have inputs on the amp that are specially designed to accommodate piezo pickups.

Good luck, and ps that is a sick looking bass!!

Gubna · #3 06-10-2008, 03:00 PM

the current set up is Passive. I was hoping to be able to continue to have it be a passive set up. but I do like the idea of having a blend knob.

and thank you. I put alot of work in to this one, see my sig file for the build thread - FrankenWick

DavidRavenMoon · #4 06-11-2008, 01:54 AM

Piezo pickups should really be buffered by a preamp because they are very high impedance. So besides being able to blend them, the preamp will get the full sound from the piezo pickup. Otherwise they can sound thin and scratchy.

Jarno · #5 06-12-2008, 04:01 AM

I have seen these bridges being offered on eBay, interested to hear your remarks on their sound, especially string to string balance. Because I don't suppose you can adjust individual string volumes?
I would be interested to hear sound samples, once you get it buffered though, I really think you need this.
There are some preamps being offered on eBay for quite reasonable prices.

Regards,

Jarno.

DavidRavenMoon · #6 06-12-2008, 02:59 PM

I'm interested in these as well. With a little effort, you can rewire the bridge for separate outputs. The connections are on the bottom.

Gubna · #7 06-13-2008, 03:54 PM

I'm thinking I might throw in a varitone as well. I mean, if I'm gonna have to add to the electronics, why not go all out?

bkbirge · #8 06-13-2008, 04:03 PM

Heck, throw in a 13-pin midi capable output and you'll have it made in the shade.

Gubna · #9 06-13-2008, 04:16 PM

Is the Bartolini MPB1-918 what I'm looking for?

Jarno · #10 07-11-2008, 12:57 AM

No answers yet, sorry for reaction so late, holidays.
I think you only need something like the schematic in the attachment, it's only a very small number of components.

See this page: http://scotthelmke.com/Mint-box-buffer.html

I wouldn't go the Bartolini way, as those are quite expensive, and the schematic is ridiculously simple.

Good luck, and please do post soundclips when you have them!

Best regards,

Jarno.

Gubna · #11 07-11-2008, 10:46 AM

thanks, but I'm not sure what that schematic really says. I would love to figure it out though so I don't have to put much more money into this bass.

Jarno · #12 07-12-2008, 02:57 PM

The zigzags are resistors and the parallel lines are capacitors, but you will need to know more than this. I think there are a couple of guitar related websites which go into electronics.

But it is a really simple schematic, and the bottomline is that such a buffer doesn't need to cost a lot of money. But you'll have to do some studying, and build a couple to get a feel for how it performs. Don't expect the first one to sound perfect though! Luckily experimenting is easy and cheap enough, some perf board and a handful of components. I had trouble finding the correct transistors, but I have found that on eBay you can find the correct types at really low prices.

Best regards,

Jarno.

**Rodent** · #13 07-12-2008, 04:05 PM

I built this bass that included a Darkstar near the traditional SCPB pickup location and a piezo saddle acoustic bridge

the Darkstar connects to one side of a passive blend pot

the piezo connects to a 9v pre-amp (Cafe Walter), which has the added bonus of a 'volume' on the input allowing me to balance the relative volume of the piezo to that of the Darkstar. the pre-amp connects to the other side of a passive blend pot

the configuration utilizes a 250k passive tone control with a 400v .047uf Orange Drop cap

if you're into the piezo thing, this is a fantastic configuration set-up that took me and my client nearly a year's worth of playing with many, many pre-amp and piezo configurations to finally achieve the tone we were looking for that was also physically capable of being constructed from off the shelf components

additional details on this build can be found in a dedicated thread in the Luthier's Forum here on TB

all the best,

R

Ripthorn · #14 07-15-2008, 07:03 AM

Hey all, I'm new here, but after doing some reading, the above conversation makes it sound so easy. My question to go along here is this: if I have a passive pickup set, does the above schematic need any alteration to interface the passive mags with the buffered piezo?

Rickett Customs · #15 07-15-2008, 07:13 AM

Quote:

Originally Posted by DavidRavenMoon

Piezo pickups should really be buffered by a preamp because they are very high impedance. So besides being able to blend them, the preamp will get the full sound from the piezo pickup. Otherwise they can sound thin and scratchy.

+1, I had my hopes shot down, the first time I started working with piezos.Buffer (and maybe a pre)+battery to run circuit, necessary evils.

Gubna · #16 07-15-2008, 01:08 PM

So there's no way I could just use a switch to switch from the piezo to the MM pickup?

Rickett Customs · #17 07-15-2008, 01:23 PM

Quote:

Originally Posted by Gubna

So there's no way I could just use a switch to switch from the piezo to the MM pickup?

I'm sure you can. or use a 3 way. But the buffer/pre is a must if you want the piezo to sound decent and not distorted or lacking low end.

Resistance comparison (ohms):
Piezos are typically around 5 meg (generally).
For example, an EMG jazz set is like 5k

**smperry** · #18 07-15-2008, 01:48 PM

I have a spare Turner preamp buffer that I'm not using...might be able to work out a trade...send me an email if interested. I'm in Oakland.

M

Bassic83 · #19 07-15-2008, 02:00 PM

That is the same piezo bridge as on my Dean, except on my Bromberg bass it is marked "Fishman". If you're looking for a great pre that is natural sounding, try getting hold of the guy who runs Audere. He does put in a piezo buffer upon request, for pretty cheap too, from what I hear.