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1. #WHICH PIEZO PICKUP FOR BASS BUILD MOD#
2. #WHICH PIEZO PICKUP FOR BASS BUILD MODS#
3. #WHICH PIEZO PICKUP FOR BASS BUILD PROFESSIONAL#

Have you ever used a condenser mic? They need phantom power because there is a preamp internal to the mic. A piezo element might as well be a capacitor in fact, the mechanics that make it like a capacitor are the same that allow it to produce an output signal. Have you noticed how almost every guitar using a piezo pickup has an onboard preamp? It's only partly about convenience.

I want to make sure I have loads of clean headroom, so anything that will help that. Is there anything else I need to do to the basic b15n preamp circuit to better work with a peizo?ĥ. Here is a pic of the small trans that I will be using (tranny on the left):ģ. Rectifier – I want to use a tube rectifier, but I am not sure if the tranny I am using will let me, or what rectifier tube to use. Should I match that, or should I got with something like a 4.7m input resistor like a lot of the peizo preamps I see online.Ģ. Input Resistor – the pickups input resistance is 1m per channel.

I will have a separate notch for each channel that is switched with a small micro switch.ġ. So I want to do a notch filter on each channel that drops 100hz, but leaves everything above about 120hz and below 80hz. Also, when playing at louder volumes, or when the acoustics of a room are terrible, my bass feedsback at about 100hz. I want to make the preamp circuits as close as possible to the original B15n but obviously setup for a piezo. It will have separate volume, treble, and bass controls for each channel, and I will use push/pull tone pots for the bass and treble boost. My bass has a stereo jack on it, so the preamp will have a single stereo input. What I want to build is an Ampeg b15n based dual channel preamp that I can use to plug into house sound, my regular bass amp, or use to record direct. It came with a preamp that sounded so bad I literally threw it away. I play an upright bass that has a dual piezo pickup. The Morris preamp idea has +20dB gain so that won't work with the above.I am on vacation for a week and I am starting to plan my next build. Long time ago but I think that was how I remember it all. You would need unity gain on the piezo output and even then the signal will likely be louder than the passive magnetic PU. in the case of a passive wired Strat circuit you would use a 250k pot and join the output of that to the output of the passive pot. The output is then mixed into the passive Magnetic circuit using a high value pot. If recall right, you might only need to use a unity gain preamp on the piezo. Yes you will need two separate preamps if you want to use them both at the same time.īe aware that the frequency response of these two types of PU's will be quite different and two independent sections with separate tone circuits might be worth exploring. No Magnetic and Piezo don't mix as the Z of each is VASTLY different.Ī Mag pu has a much much lower Z (impedance) and will just load down the piezo and it will hardly work. Try it if you have bad FB, you might be surprised.

I'd guess guitar luthiers would reject the idea as folly.

#WHICH PIEZO PICKUP FOR BASS BUILD PROFESSIONAL#

for those that may think it a rather non professional fix up, Violin luthiers are known to use a post to reduce resonance between the face and back, moving it around to find the sweet spot.

#WHICH PIEZO PICKUP FOR BASS BUILD MOD#

As it's only wedged in place the mod is usually reversible. Regarding low freq FB I've found that a central post wedged between bridge and back can help in some instruments, A case of suck it and see if it helps. The early bug type transducers did tend to suffer bass loss without really hi Z, like 10meg. Past 2meg is just asking for low freq FB issues, especially on large body guitars. I've found that most of the bridge under saddle transducers don't need excessively high Z preamp inputs. You may need to experiment with a few circuits to find a happy solution. As can be seen here the LR Baggs output is almost half of the Morris and quite different curves. The output signal strength as well as the response cuves vary a lot.

#WHICH PIEZO PICKUP FOR BASS BUILD MODS#

My Preamp circuit is a copy of an old Morris preamp with a couple of slight mods to fix the excess bandwidth which is a common issue for Piezo pickups.Īctive Piezo's are a brilliant idea but the outputs are often very different. This Screen shot is an A/B comparison of the 2 circuits output curves. I've just been running some tests of the LR Baggs circuit as well as something I built a few weeks back to fix a friends guitar which had a dead preamp module.