Noise Machine

[fieldwrangler]

Folks -

Short version is that I wanted to make a powerful broadband noise source for pickup testing.

Then I saw the head unit of a paper shredder in the corner of my shop.

No building necessary.

[David King]

i have a little benchtop planer with squealing bearings that would put your shredder to shame i bet.

[bbsailor]

One easy source for a 60HZ noise source is a Weller 100W or larger soldering gun. You can easily move it different distances and orientations from the pickups and hear it directly through the guitar amplifier.
Another source of broadband noise is a desktop computer which generates a very broadband source of noise. Just try moving a Stratocaster or Telecaster style single coil pickup guitar near the computer and listen.

High impedance pickups wound with 5K to 10K turns of thin magnet wire make good noise antennas. That is why low or medium impedance pickups with either passive voltage boosting transformers or active amplifier circuits with a gain of up to about 10X can make another alternative to achieving a better signal to noise ratio.

One of the noisiest places to play guitar is where there are many lighting dimmer circuits, such as some stages, or rooms where the whole room seems to be located inside of a noisy coil.

Joseph J. Rogowski

[John Kolbeck]

Folks -

Short version is that I wanted to make a powerful broadband noise source for pickup testing.

Then I saw the head unit of a paper shredder in the corner of my shop.

No building necessary.

You're asking for broadband noise; you mean white noise? An AC appliance won't really give you broad band noise I don't think. That would produce a handful of specific frequencies.

How about a cheap function generator capable of producing white noise, then hook that up to cheapo single coil guitar pickup, crank up the output, and the pickup will transmit the white noise.

[eschertron]

You're asking for broadband noise; you mean white noise? An AC appliance won't really give you broad band noise I don't think. That would produce a handful of specific frequencies.

How about a cheap function generator capable of producing white noise, then hook that up to cheapo single coil guitar pickup, crank up the output, and the pickup will transmit the white noise.

I don't think it was made apparent whether the OP wanted EMI noise or acoustic noise. I imagine he wants to check his pickups for microphonics.

[fieldwrangler]

i have a little benchtop planer with squealing bearings that would put your shredder to shame i bet.

Wouldn't surprise me!

[fieldwrangler]

One easy source for a 60HZ noise source is a Weller 100W or larger soldering gun. You can easily move it different distances and orientations from the pickups and hear it directly through the guitar amplifier.
Another source of broadband noise is a desktop computer which generates a very broadband source of noise. Just try moving a Stratocaster or Telecaster style single coil pickup guitar near the computer and listen.

High impedance pickups wound with 5K to 10K turns of thin magnet wire make good noise antennas. That is why low or medium impedance pickups with either passive voltage boosting transformers or active amplifier circuits with a gain of up to about 10X can make another alternative to achieving a better signal to noise ratio.

One of the noisiest places to play guitar is where there are many lighting dimmer circuits, such as some stages, or rooms where the whole room seems to be located inside of a noisy coil.

Joseph J. Rogowski

I've used (and been used) by all of those sources.

Admittedly, I recall once being worried about the potential demagnetization effects of the Mighty Weller...

[fieldwrangler]

You're asking for broadband noise; you mean white noise? An AC appliance won't really give you broad band noise I don't think. That would produce a handful of specific frequencies.

How about a cheap function generator capable of producing white noise, then hook that up to cheapo single coil guitar pickup, crank up the output, and the pickup will transmit the white noise.

You're right about the spectral profile of the AC appliances. However, it does seem to represent real world gremlins well.

[fieldwrangler]

I don't think it was made apparent whether the OP wanted EMI noise or acoustic noise. I imagine he wants to check his pickups for microphonics.

That, too!