An EUB Build

[Ezrocks4u]

Can we get some full body shots? Looks good, want to see the full bass sometime.

 

[Tedward]

I seam to have forgotten that one. I'll get one posted.

Tedward

 

[~Ethan~]

This is great! I just started rough drafting an EUB so I'm keenly interested in how you've gone about making yours. Looks amazing so far!

 

[ctmullins]

Very very very cool! Does that fdeck pre actually do impedance matching? I don't really know what I'm talking about, but others do. I have a piezo-equipped semi-hollow that I built, and I used a Cafe Walter PZP-1 piezo buffer. Did wonders for the piezo tone.

 

[Tedward]

Full body pics

Tedward

 

[Remyd]

So pretty! Love your work!

 

[Tedward]

Thanks for the compliments

Tedward

 

[SBassman]

Very nice and very interesting.

I'm thinking that you have too much mass in that bridge, making it hard to get the vibrations transferred from the strings to the piezos. Look at an upright bass bridge - much less mass.

 

[Tedward]

SBassman, the next thing I'm going to do is remove some wood from the bridge.

I'm also getting a thumping from my finger hitting the upper string. Could be my technique or the pickup / electronics.

Tedward

 

[Tedward]

Got the bridge trimmed down and I'm still not happy with the sound. It sounds highly compressed you know with a hard attack and soft short sustain. Even with the fdeck.
I'm scratching my head, any ideas?

Tedward

 

[GKon]

I'm by no means a luthier nor an expert on EUB's. However, on my Harley Benton (same as Palatino) EUB, I've put a piece of
bicycle tire innertube under each foot of the bridge, as suggested on the various Palatino EUB megathreads on TB.
It helps to warm and mellow the sound a bit. Not sure about the sustain.

I hope this helps.

 

[Tedward]

Thanks for the suggestion GKon,
I tried some inner tube rubber from a small wheel. It might be too thick though. I'll check on a bicycle tube, maybe bicycle tubes are thinner. The tube I used is .055" thick.

Tedward

 

[GKon]

I don't actually know the thickness of the inner tube I used. Sorry, I can't help you there.
Some other people used rubber matting that you put on a shelf. You can maybe try some heat
shrink tubing as well.

Let me know if it works out at all.

 

[ctmullins]

The whole point of piezo pickups is to transmit the physical vibrations of the strings through the instrument directly to the piezo elements. Rubber strips will attenuate that physical transmission. So they might be helpful in certain cases, but it's kinda like putting a governor on a sports car.

There are significant variations in the response of different piezo elements, so it's possible that your dissatisfaction could be addressed by trying different piezos.

I still want to know whether your preamp is properly impedance matching.

 

[Tedward]

ctmullins, yes the preamp is designed for impedance matching. I did order some more piezo elements the other day thinking that could be the problem.

Tedward

 

[Tedward]

Okay, I made a new set of pickups with the new piezo elements. After they were soldered up I noticed that they buzzed. I found out that they were not shielded. More work to do. I coated the exposed ceramic with some lacquer and let it dry. I then applied copper shielding tape to both sides. Since the adhesive is conductive the lacquer acted as an insulator. I let the copper contact the ground solder joint to complete the shielding. Now they are silent. Installed them under the bridge and they sound really good. I guess not all piezo elements are alike.

Tedward

 

[ctmullins]

Excellent! Did you install them with or without the inner tube rubber?

 

[Tedward]

With out the inner tube rubber. When I get some I'll give it a try and see how much difference it makes. I have also been thinking about dipping them in liquid latex like the pros do.

Tedward