Double Bass I think I made a usable DIY pickup for 2$

[Nohrellas]

I doubt this will be interesting for anyone who already owns a professional pickup system but for people who are on a tight budget this might be helpful.
You may have already seen these cheapo contact microphones/piezo pickups that you can order from china (or just buy them imported from an amazon seller or ebay)

(I started out with the one on the first picture but it's the same thing inside the plastic shell)

All I did was dribble over some CA glue (epoxy might be better but it worked just fine) to get it just over the desired thickness, let it dry properly and then sand it down to a tight fit between the bridge foot and the wing of the bridge.

I took some advice from the people at upton bass, I left a bit of a hump in the middle of the glue spot to create a "hotspot" for the piezo element. It fits snugly between the foot and the wing and seems to work just fine. As for the mounting method of the input jack, mine came with these velcro strips that I created a loop for the strings with and then I added a ball end to the jack with tape so it doesn't slip through the velcro holder.

At the end of the day I bought 5 of these pickups for 10 bucks on amazon, so it comes out at 2€ per pickup, if you just buy the piezo elements and solder on an input jack that is suitable for mounting on an UB it's even cheaper (one piezo element costs less than 50cents).

The title says that I "think" I made a usable DIY pickup, that's of course up to the listener. I have one short sound sample that i just recorded since I want to experiment with it and see if I can get more out of it. piezo pickup -> a bunch of true bypass pedals -> boss rc30 looper -> amp
I miced the amp with a small condenser microphone. As for the EQ, I turned down the highs a considerable amount to get rid of the squeakiness of piezo pickups, turned down the lows a bit since they were quite boomy and boosted the mids a tiny bit. It certainly seems like a usable sound to me that could be used live.
Here is a link to the recording and I'll also attach the mp3 file to this post:
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[Martin Beer]

I've found that with assembling your own pickups from piezo elements, the main challenge is to make the package and connections sufficiently well shielded and robust, so that they're dependable in use. The actual signal from them is often quite useable, it's those other factors that have caught me out when I've experimented with piezo elements in the past.

 

[Francois Blais]

I got one of these elements but it didn't work quite well for me.
Granted I didn't invest much time into it like you did, since I already have a few "pro" pickups.
Homemade piezos are really hit and miss.

 

[Nohrellas]

I've found that with assembling your own pickups from piezo elements, the main challenge is to make the package and connections sufficiently well shielded and robust, so that they're dependable in use. The actual signal from them is often quite useable, it's those other factors that have caught me out when I've experimented with piezo elements in the past.

Interesting, I guess I'd need to try and test it in a noisy environment to see if it requires more shielding. That said I had good success with shielding my diy electronics on an archtop guitar by covering the wires in copper foil that is connected to ground and using heatshrink tubing as a new mantle. Something similar would probably work here.

I got one of these elements but it didn't work quite well for me.
Granted I didn't invest much time into it like you did, since I already have a few "pro" pickups.
Homemade piezos are really hit and miss.

Obviously they are hit and miss, but I'm pretty excited that I'm getting a decent signal from this cheap little alternative to 100$+ systems. I'm currently trying to get a more even and stable fit in the bridge and maybe I'll need some more shielding like someone else mentioned.

 

[DoubleMIDI]

Shielding is very important because of th very high output impedance of the piezo disks. Also a relatively short connection to an impedance buffer or preamp with 10 MegOhms input impedance. That way you get a better sound with less piezo quack than with pedals with 1 MegOhms input impedance or less.
Bridge wing pickups are made from thicker piezo crystals than the thin wafer on a piezo dusk and therefor the input impedance from the following (pre-)amp could be a bit lower (1 to 5 MegOhms). Mechanical fitting of the piezo assembly to the instrument is very important too. If you put a spot on the piezo disk you get a louder signal, but the stress on the piezo crystal is high and it may break earlier or later.

A lot of people (including myself) experimented with piezo disks. The point is, that you might get a lot of experience using a lot of time and at the end pay as much as for a cheaper professional pickup. Some of them might be less good than your fifth modification, others a lot better.
Piezo disks, if clamped not to vibrate freely, can sound very good, but the need that high impedance buffer if preamp. A buffer is a cheap DIY thing, but you need to have some experience with electronics. A preamp is much more expensive and eats what you have saved for the pickup easily. The HPFpre is probably the cheapest ready to go solution with a 10 MegOhms input impedance.

 

[james condino]

We generally agree that all of the commercial pickup producers have gone through the same rookie choices that your are going through right now. Given enough time and experimentation, you'll find the correct match and probably won't spend much more that $10 for that individual unit.

Most TB'ers would be horrified if they knew how little in parts it costs for the $200 pickups sold on the market. As a manufacturer, I've purchased some of them for under $30 from the brand name companies. We all know that if you spend $500, you'll find a commercial peizo that works well for your needs and save a ton of time, and likely money.

All that is nice, but life is more than just a quick commercial transaction gratification. If experimenting and problem solving is appealing and stimulating to you, then keep working with it and tell all of the naysayers to %$#@ &%% and keep building them!

 

[Nohrellas]

I tinkered around with it some more, made the package thicker again to sand it down to a nice smooth surface with maximum contact area to the bridge. I think it actually sounds better now, more balanced, and it definitely sits more securely in the bridge to the point where I'm comfortable to just leave it in there.
I also took the precaution to shorten the wire so it has less chance of becoming microphonic or pick up weird sounds.

As for the shielding, I threw everything I have at it from LED lightbulbs, to my phone during a call, computer monitors, etc. and I'm not getting any interference. It'll still be interesting to see how it behaves on stage but so far it seems usable.

 

[Povl Carstensen]

I actually think the sound in the clip is not so bad. A bit piezo grit ofcourse, but also a useable low end "kick". There is a bit of hiss, I suppose that is not from the pickup?

 

[Nohrellas]

I actually think the sound in the clip is not so bad. A bit piezo grit ofcourse, but also a useable low end "kick". There is a bit of hiss, I suppose that is not from the pickup?

The hiss you can hear is definitely from my amp. I have another short sound sample here with the second version of the piezo I tinkered around with today. Again, I miced the cab. I'll see how I can get the pickup to sound straight into my audio interface with software EQ tomorrow probably.
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[Nohrellas]

Here is a short sample just straight into my audio interface, recorded with audacity without any EQ or any effects added. That's probably a more useful test of how it sounds now that I think about it, but I already had the looper and the cab set up so that was nice and quick to test it out.
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And here is the same clip with some compression and EQ:
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[diegom]

Very interesting project! @Nohrellas, could you post better pictures of the mount? I just can't visualize the "between the foot and the wing" without affecting the action too much...
Thank you for sharing your successful DIY pickup! I really like the sound of the second clip!

Diego

 

[Nohrellas]

Very interesting project! @Nohrellas, could you post better pictures of the mount? I just can't visualize the "between the foot and the wing" without affecting the action too much...
Thank you for sharing your successful DIY pickup! I really like the sound of the second clip!

Diego

Sure, here are a few pictures from a few different angles. The piezo disk in the glue package (to make it thicker and so the piezo element doesn't break) is wedged in that spot of the bridge and the input jack is on a velcro loop/assembly at the tailpiece.
None of this affects the action at all, and it's completely reversible the way I did it.

 

[diegom]

Sure, here are a few pictures from a few different angles. The piezo disk in the glue package (to make it thicker and so the piezo element doesn't break) is wedged in that spot of the bridge and the input jack is on a velcro loop/assembly at the tailpiece.
None of this affects the action at all, and it's completely reversible the way I did it.
View attachment 3362995
View attachment 3362993
View attachment 3362994

Perfect! That first shot really cleared it up. I wonder if you'd get different response if you were to mount it on the treble side...

Thanks for the pics!

Diego