ABOUT

Hi I am Neri. I am musician, and electrical engineer. I have more than 20 years of working experience, and more than 30 years of experience working with electrical devices. Living in Austin for many years, I played at many live shows with my bands. 

The biggest pain of any working musician is setup and teardown of the equipment: amp, cables, and pedals. As I was brainstorming how I could reduce my own setup and teardown time for my live shows, I came up with the idea to build a standalone, rechargeable, DC power supply for my guitar pedals. This design makes it a full circle for me, as I have build my first AC-DC 12 Volt charger from scratch in 1993, which I’ve successfully sold.

Here I show a device that can power up any guitar or bass pedal, thus eliminating need for external DC power supply and long cables from the AC grid. I call this device “Mendaudio DC Battery Pack”. The first prototypes are built here in Austin in my garage, utilizing off the shelf PCB components, and custom handmade DC circuits from the web. 

The main objective was to build safe and reliable devices that just work. with battery safety in mind, I have reviewed and tested a number of lithium ion cells available on the market including LG, Panasonic and others. 

The DC Battery Pack device includes one off the best Li-Ion cells in the world, with advanced protection electronic circuits, protecting against overvoltage, undervoltage, overcurrent, and short-circuit conditions. 

One of the primary objectives for me was to build a prototype device that is completely safe for anyone to use. I have achieved that goal with the Hybrid Chemistry Battery Cell made and assembled in Japan, and tested in the U.S.A. 

The DC Battery Pack Hybrid Li-Ion Battery Cell can be utilized for 1000 full charge/discharge cycles. With the full manual switch control of the DC Battery Pack device, and the battery cell completely disconnected while device is off, the chance of thermal runaway is practically null.

The DC Battery Pack device greatly reduces setup time on stage, as well as tear down. Cable management is much simpler. The AC-Line level noise that can be notorious on some stages is completely mitigated. The DC Battery Pack device can power up to 10 pedals at a time. When powering 1 guitar pedal (@100 mA current draw, example: distortion pedal), the single charge on the DC Battery Pack device lasts up to 35 hours of non-stop operation. With Turbo-Charge (2 Amps), the Device can be recharged in less than 2 hours from the AC grid. Other means of recharging are possible, including solar cells, mechanical gear rotation, 12 Volts from the car, and others. 

 The main hardware novelty feature of this device is a “Battery Cell Voltage Status Monitor LEDs” feature. When the battery cell is full all four LED's are lit up. As the energy is discharged from the battery cell, the LED brightness is reduced proportionally. This allows instant visual checking of the power level of the battery cell, so that there are no surprises in the middle of the show. Therefore, it is very easy to see exactly how much power is left in the DC Battery Pack device, before the next recharge is required. In the case of “Shelf/Storage mode”, the battery cell is completely and safely disconnected from any connections via hardware mechanical switches, achieving excellent low self-discharge performance.

 The DC Battery Pack device is built without any microcontrollers, Wi-Fi, Bluetooth, or any other modern modules. This significantly reduces the complexity, and the cost to build (including Bill Of Materials). All major controls are implemented with manual hardware switches. Therefore, the possibility of something breaking down is greatly reduced. 

The DC Battery Pack device was tested at temperatures -10 to +30 Degrees Celsius, without any degradation of performance. New customers will receive 3-year warranty on all the parts and guaranteed performance of the Li-Ion Battery Cell. Parts list: Case, Lid, Connectors, Switches, Wires, DC-DC Boost Converter PCB, LED Battery Cell Voltage Status Monitor PCB, Cell Holder, and the Battery Cell. 

This plug and play device lets the artist focus on the performance instead of the setup (and tear down) of the DC Power converter with long cables across the stage to AC plugs. The Mendaudio DC Battery Pack device truly reduces the setup time on stage before the show, and in-between band switchovers. There are no more clunky long power cables on the stage that require additional cable management for the Pedals. Plus, when travelling and performing internationally, there are no more AC converters needed! The Mendaudio DC Battery Pack device will work anywhere in the world, seamlessly, and reliably!