Piezo PUs for electric bass

[carpet69]

Hi guys

I'm radically modifying my cheap 4 strings bass. I'm adding the low B, repainting the body with a design, removing the frets and changing the PUs. My questions are related to the latter.
I would like to obtain a sound as close as possible to a double bass' one. I was thinking to get rid of the original single coils (filling the holes with maple or other wood types) and get bridge piezoes.
Because of the 5th string, I'm forced to use single unit bridges (s. bridge.jpg) and put piezoes following this guide under each unit. The question is: how to connect all the single piezoes to the internal preamp (by the way: which preamp would you suggest?). Are the wires coupled together?

Thanks in advance

Carlo

[Koeda]

GT makes a 5er:
http://www.graphtech.com/products.html?SubCategoryID=80

they also have a pre - or I use the ghost saddles with bart pre's: an MPB2-918 with the NTBT
David

[Bass-desires]

Also sleezebay has a few. How are you going about modding it to a 5 string? I'd be curious to know. Also, do you plan to use the piezo on the B string only? If you follow that guys direction, your going to have 10 leads going to the preamp/output just for the piezo. Try soldering that nicely! lol

[azflyman]

Please don't get rid of the mag picups. I have a Zeta piezo bridge and it sounds a dead without a little mag. Piezo's dont always sound the same on every bass and you might not like that sound by itself, it may not be what you think.

az

[carpet69]

Hi guys

thanks for your answers. As I mentioned in my original post, I'm forced to use 1-string units in place of a conventional bridge cause of the changed strings' spacing (I'm adding the B).
In the meantime I found here that the piezos can be connected in parallel to a preamplifier (J1 can be replaced with something like this)

@azflyman: can you please let me know how the piezo and mag signals are mixed in your bass?

@Bass-desires: I'll do an additional 16mm hole on the headstock, file a new nut, and use the 1 string bridges. I already removed the frets and used wood paste filler. I initially wanted to apply epoxy resin to the fingerboard (Jaco's method) but I think I'll leave that.

Cheers

Carlo

[nic salsus]

Originally Posted by azflyman

Please don't get rid of the mag picups. I have a Zeta piezo bridge and it sounds a dead without a little mag. Piezo's dont always sound the same on every bass and you might not like that sound by itself, it may not be what you think.

Piezos can sound thin on big sounding acoustic instruments.
Put one on a solid body and it's probably gonna sound how in comparison? Piezos pick up the sound of the body.
I've used a lot of piezos on a lot of instruments and putting one on a solid body always seemed like putting low profile racing rims on a lifted pickup truck....nothing wrong with low profile rims or with a lifted pickup trucks just a combination that doesn't make much sense.

I've heard it done effectively but not without a huge amount of work to EQ it into something pleasing to the ear.

[carpet69]

Originally Posted by nic salsus

Piezos can sound thin on big sounding acoustic instruments.
Put one on a solid body and it's probably gonna sound how in comparison? Piezos pick up the sound of the body.
I've used a lot of piezos on a lot of instruments and putting one on a solid body always seemed like putting low profile racing rims on a lifted pickup truck....nothing wrong with low profile rims or with a lifted pickup trucks just a combination that doesn't make much sense.

I've heard it done effectively but not without a huge amount of work to EQ it into something pleasing to the ear.

I wasn't planning to glue a buzzer to the solid body. I was actually thinking to adapt piezo material to the 1 string bridges so they will pick up the single string. It's the same principle of the commercial piezo bridges.

[nic salsus]

Originally Posted by carpet69

I wasn't planning to glue a buzzer to the solid body. I was actually thinking to adapt piezo material to the 1 string bridges so they will pick up the single string. It's the same principle of the commercial piezo bridges.

I completely understand that. I'm not even trying to turn you away from playing with the piezos....experimenting is cool. Just saying major EQ is required and my philosophy is it's better to start with something that you can run with a minimal amount of EQ....something that actually sounds good to begin with. I'm never really sure what people think they're going to get with a piezo on a solid body.

[Koeda]

Originally Posted by carpet69

Hi guys
thanks for your answers. As I mentioned in my original post, I'm forced to use 1-string units in place of a conventional bridge cause of the changed strings' spacing (I'm adding the B).

Why not just add a 5 string hipshot piezo bridge from GraphTech? Save some frustration and looks and sounds good too. Easy wire harness for each pu as well. Home made sounds possible - but the ghost saddles really sound great and will perform well with even string volume. Tried the home made route and was not satisfied, but love the ghost saddles.

@azflyman: can you please let me know how the piezo and mag signals are mixed in your bass?

Bartolini MPB2-918 or GraphTech pre do this.

Piezos can sound thin on big sounding acoustic instruments.
Put one on a solid body and it's probably gonna sound how in comparison? Piezos pick up the sound of the body.
I've used a lot of piezos on a lot of instruments and putting one on a solid body always seemed like putting low profile racing rims on a lifted pickup truck....nothing wrong with low profile rims or with a lifted pickup trucks just a combination that doesn't make much sense.

I've heard it done effectively but not without a huge amount of work to EQ it into something pleasing to the ear.

The Ghost saddle pickups sound bassy and full even with the eq flat - especially good on the fretless (no clanking from the strings on frets). Vastly different animal than the strips under an acoustic bridge in performance and sound for a solid body.

[nic salsus]

Originally Posted by Koeda

The Ghost saddle pickups sound bassy and full even with the eq flat - especially good on the fretless (no clanking from the strings on frets). Vastly different animal than the strips under an acoustic bridge in performance and sound for a solid body.

I admit I don't think I've checked those out even in passing in a store. Is the flat EQ you're talking about with any preamp or one that was designed (and voiced) for the Ghost saddles? I like the cleanliness and concept of piezos and if I could find something that worked I'd like to try them on a solid body. I always thought Steve Swallow's old Parker bass used them very effectively.

[Koeda]

Originally Posted by nic salsus

I admit I don't think I've checked those out even in passing in a store. Is the flat EQ you're talking about with any preamp or one that was designed (and voiced) for the Ghost saddles? I like the cleanliness and concept of piezos and if I could find something that worked I'd like to try them on a solid body. I always thought Steve Swallow's old Parker bass used them very effectively.

Not the GraphTech one - I have a Bart MPB2-918 with the NTBT. Eq is on the NTBT with Bass/Treble is flat. Bart has a buffer with a bass boost MPB1-918, but don't know if the GT is that way or flat like the one I have the MPB2-918. I think the piezo saddles work well on a fretless, but a piezo drove me crazy on a fretted acoustic-electric I had for a while. Too clanky on the frets for me. I think for the solid body having the piezo element in the saddle is the way to go.

[eutgard]

GT saddles + GT pre on MIJ P strung with Fender 9050M flatwound.

http://www.mediafire.com/?rjlwritm2zr

Somewhat weak E, but I've soved this problem by raising the saddle a little - You need some pressure on the saddle.

[nic salsus]

Originally Posted by eutgard

GT saddles + GT pre on MIJ P strung with Fender 9050M flatwound.

http://www.mediafire.com/?rjlwritm2zr

That works for me!

[carpet69]

Originally Posted by Koeda

Why not just add a 5 string hipshot piezo bridge from GraphTech? Save some frustration and looks and sounds good too. Easy wire harness for each pu as well. Home made sounds possible - but the ghost saddles really sound great and will perform well with even string volume. Tried the home made route and was not satisfied, but love the ghost saddles.

If I want to add a string while keeping the same fingerboard, I'll end up having a 15mm space between each strings couple at the bridge. I checked around some time ago and the lowest string spacing allowed by a commercial 5-strings bridge is 18mm. Of course I'd take a commercial piezo bridge having the needed characteristics if there were one.

[nic salsus]

Originally Posted by carpet69

If I want to add a string while keeping the same fingerboard, I'll end up having a 15mm space between each strings couple at the bridge. I checked around some time ago and the lowest string spacing allowed by a commercial 5-strings bridge is 18mm. Of course I'd take a commercial piezo bridge having the needed characteristics if there were one.

If you could get piezos into this Kahler bridge it adjusts narrow enough to suit your needs. From the pic it doesn't look that practical but I've been investigating bridges to mod a 4 string into a 5 and this is by far the most adjustable bridge for that purpose.
http://www.wammiworld.com/u7450.html

[SebbyNC]

You could drop a mail to Brian at BestBassGear, I got my piezo Hipshot/GraphTech bridge from him and I know they can make different string spacings (they are just not in stock generally).
Otherwise, if you use your single unit bridge, you should check GraphTech or RMC pickups and see if they make piezo saddles which can fit into the ones you'll get (those little black things that are in direct contact with the strings). It's likely that either one of these 2 brands make the correct saddle size. Then you can get the piezo buffer from them too, or try the Bartolini buffer, or try the one made by Cafewalter.

I have a friend who put the Hipshot/GraphTech bridge with their AcoustiPhonic buffer on his Cort B5 fretless bass with flatwound nylon coated strings, and it really has an upright bass-like sound (even closer to a real upright sound than the NS Design Wav 4 EUB I owned).

[bassbenj]

Originally Posted by carpet69

Hi guys

thanks for your answers. As I mentioned in my original post, I'm forced to use 1-string units in place of a conventional bridge cause of the changed strings' spacing (I'm adding the B).
In the meantime I found here that the piezos can be connected in parallel to a preamplifier (J1 can be replaced with something like this)

@azflyman: can you please let me know how the piezo and mag signals are mixed in your bass?

Carlo

You can connect piezos in parallel but they'll work much better in series. But remember that piezos pick up hum like MAD if they aren't totally shielded so all those wires at the bridge connecting things in series must be shielded somehow!

Don't forget that piezo have to be fed into a VERY high impedance preamp to work for bass. I Strongly suggest getting a Fishman Powerchip. This is a circuit board with volume control (for the piezo) which will work the piezo AND mix in a magnetic. Even run them stereo if you have a stereo cable. It's active and takes a battery.

The magnetic pickup just uses the standard volume and tone passive circuit before it goes to the PowerChip. This gives you Vol (piezo), Vol (mag), Tone (for mag) plus if you want (I recommend it) a toggle switch for mag/both/Piezo pickup selector. This thing works like a champ! (take wallet!)

I URGE you not remove all magnetic pickups. The bass will be much better if you include a neck magnetic pickup. Piezos are very percussive and very bright and a magnetic neck pickup to mix in will help you add a deep bass dimension to your tone. I wish my piezo acoustic had a magnetic neck pup.

[SebbyNC]

I agree that magnetic plus piezo is cool to have. On my bass, the piezo has such extended lows and highs that blanding with the magnetic pickups adds some tasty mid-range.

[carpet69]

@sebbync: thanks for the graphtec suggestion. In fact this saddle is the one that fits the 1 string bridges that I have.

@nic salsus: too bad I didn't know about the Kahler bridge before (I had already bought the unit bridges some time ago). The link you posted gave me the idea of making a chrome plate where the unit bridges can be hooked (and the distance among each other can be adjusted)

To all the guys suggesting me not to get rid of the mags: the instrument is really cheap and old. The sound of original 4 strings PUs is not worth to mix to the Ghost midi kit (I was thinking to install that too). Replacing the mags with new ones is a hassle I can avoid, as not many 5 string PUs would work properly with a string distance of 15 mm

I'll post some pics and mp3s when I'm through with this project.
Thanks again for your help and suggestions

Cheers

Carlo

[Bassymmetric]

What about this?

http://www.graphtech.com/product-519-2/