Beambots are tiny, minimilistic, solar powered robots. At their heart is a solar panel that is too weak to power the robot continuously. So instead, the solar panel is used to charge a large capacitor. When the capacitor is full, the robot turns on and begins to drain it. Then when it is empty, the robot turns off and it charges again. There are a few different circuits that can accomplish this,
Free Bollard Audio Samples
August 23 2024
I recently made a music video where I sampled bollards outside of a government complex using a Metal Marshmallow Pro contact mic. I turned the samples into a sick beat. That video is at the bottom of this post. Here I have uploaded the bollard audio samples for anyone who is interested in using them. I'm too lazy to give them any specific license, but they are free and you can use them for anyth
Impuse Response for Plate Reverb
July 25 2024
I recently made a video showing how I used my washing machine in conjuction with a Metal Marshmallow Pro contact mic to make a plate reverb unit. That video is at the bottom of this post. In that video I made an impulse response of my washing machine so other people can use it as the basis of reverb for their own recordings. The purpose of this blog post is to host the original impuse response f
Metal Marshmallow Pro's Subsonic Frequency Response
November 8 2023
A few people have asked recently about Metal Marshmallow Pro's ability to record very low frequencies below the range of human hearing. This is difficult to measure for several reasons. The initial challenge is finding something that can drive the microphone at just a few Hz. Second, standard audio hardware typically attenuates very low frequencies, and the details are not usually published
Can you attach multiple piezo discs to a single contact mic preamplifier?
August 25 2023
Several people have asked recently whether it is possible to connect several piezo discs in parallel to a single Marshmallow DIY contact mic preamp, as is depicted in the image at the top of this post. Before I get into the details, note that
doing so will not give you stereo or multichannel audio. All of the discs will be combined into a single mono audio channel. If you want multichanne
How To Build A DIY Aeolian Harp
August 3 2023
https://www.youtube.com/watch?v=hcTzLfkdIyA
Raw Materaials
These are the raw materials you will need to make your Aeolian Harp.
Square Section Hardwood
Quantity: 1
Size: 1.5 x 1.5 x 20 inches
Size: 40 x 40 x 400 millimeters
Price Each: 13.98 USD
Cut Into:
End Blocks
Quantity
Phantom Powering a DIY Contact Mic
July 17 2023
Update: We now offer a Phanotom Powered version of the DIY preamp. That one was optimized for this purpose and will have slightly better performance than the one described in this article. This artilce is left here for informational purposes, but if you need a phantom powered preamp, just get the new one intead of building this circuit yourself.
Several people have asked me recently if the Ma
Can Metal Marshmallow Record Ultrasonic Sounds?
June 1 2023
Humans can hear sounds up to about 20kHz for children and 16kHz for adults. Sounds with a higher frequency than this are considered ultrasonic. Many microphones can easily hear ultrasonic frequencies. But what about Metal Marshmallow contact mics, how high can they hear?
Theoretical Limits
The theoretical upper limit of the frequency range of each Metal Marshmallow microphone is listed below
Warranty for Metal Marshmallow Products
May 26 2023
Covered products can be returned or exchanged for any reason within 60 days of the original purchase date. If the product is defective, Metal Marshmallow LLC covers shipping costs. Otherwise the customer covers shipping.
What products are covered?
This Limited Warranty applies to all products sold on metalmarshmallow.com, except where stated otherwise in a product's description. It als
Can I plug a contact mic into a guitar pedal?
May 22 2023
Over the years, several people have asked me if they can plug a Metal Marshmallow contact microphone directly into a guitar pedal. The issue is that Metal Marshmallow outputs a line-level signal, whereas guitar pedals are designed to accept input from a guitar, which is an instrument-level signal. In general, line-level is higher than instrument-level, so will this overload the pedal?
Microph
