cMoyBB™ Do-It-Yourself Guide
Forward
The concept of the Bass Boost cMoy began in the summer of 2006 when I took an interest in DIY audio. The original cMoy design from 1998 was nothing new. In fact, I already owned a cMoy I had purchased from eBay. But as an electrical engineering student, I was intrigued by potential modifications of the simple circuit and wanted to increase the subpar bass response of my Sennheiser HD-280 Pro headphones.
After spending days reading tutorials, message boards, shopping for parts, and then tweaking a cMoy on a breadboard, I spent more than eight hours constructing my first hand built cMoy on protoboard. It didn't work. I spent another eight hours assembling a second (and functional) cMoy, later realizing I had forgotten just one wire on each channel of the first amp. In all, it took over 25 hours to build the same amplifier many others before me had built over the previous eight years.
Some months later, the first Bass Boost cMoy was born on a messy breadboard. Thrilled with the result, I decided to produce a few nicer versions of the amplifier for myself on professionally printed circuit boards and share the great circuit with fellow audio enthusiasts. The cMoyBB has since found owners in more than 36 nations around the world.
The cMoyBB can be electrically completed in under 30 minutes, saving you many tedious hours over building a regular cMoy. More importantly, the cMoyBB cannot be matched by other cMoys in terms of audio quality.
Why DIY?
It is important to me to promote engineering creativity and progress, thus, I am upholding DIY tradition and making the cMoyBB available to everyone. Music, or audio in general, is a subjective topic. I greatly prefer the sound of the cMoyBB over other entry-level amplifiers. Still, you may wish to experiment with different resistors, capacitors, jacks, enclosures, or something more exotic. I suggest just a few alternative components in the BOM, but building the amplifier yourself gives you the freedom to build a unique, top-notch cMoy with practically an unlimited number of options.
Will building a cMoyBB myself save money?
The cMoyBB is a high-end version of the cMoy. It was not meant to be cheap. A cMoyBB built to standard specifications will easily exceed $50 USD, plus the cost of any tools you may not own (not to mention your valuable time and labor).
DIY headphone amplification is for those who possess the interest and/or knowledge to build their own amplifiers. In other words, this project is not intended to save you money. It is always fastest and easiest to buy a preassembled amplifier.
Where is the schematic?
I would like to share the cMoyBB's schematic. However, the cMoyBB cannot be properly reproduced without its custom printed circuit board (PCB). Achieving proper signal characteristics and decoupling is essential to the amplifier's performance. These features cannot be reliably implemented with protoboard or homemade, single-layer PCBs. The cMoyBB's PCB has undergone numerous revisions and analog signal integrity analyses. I specialize in high frequency analog circuit design; amateur PCB designers (even other electrical engineers) usually lack the knowledge to design a PCB with equivalent performance. If I were to release the schematic, cloned versions of the cMoyBB would undoubtedly produce inferior sound quality and tarnish the amplifier's excellent reputation.
As explained above, it wouldn't be worth anyone's time to try to copy the circuit by hand. The cMoyBB v2.02 PCB is priced cheaply (barely more than protoboard) and is absolutely necessary to achieve great sound quality. For these reasons, I choose not to reveal the schematic. You are still welcome to ask circuitry-related questions.
Skill and Knowledge Prerequisites
Although this guide should single-handedly provide you with the necessary information to build a cMoyBB, I highly recommend browsing through Tangent's cMoy tutorial and Chu Moy's original article. The cMoyBB is a derivative of the original cMoy design. Consequently, I will not bother repeating Tangent's exceptional work. If you are not already skilled in soldering, definitely check out Tangent's tutorial videos and practice before you begin.
Usage Policy
This project is intended for personal use only. Commercial usage of this DIY Guide and/or the bare cMoyBB circuit board is strictly prohibited without prior written authorization. cMoyBB is a trademark of JDS Labs. As such, the cMoyBB circuit board may not be copied or cloned.
Proceed to Assembly Guide
Forward
The concept of the Bass Boost cMoy began in the summer of 2006 when I took an interest in DIY audio. The original cMoy design from 1998 was nothing new. In fact, I already owned a cMoy I had purchased from eBay. But as an electrical engineering student, I was intrigued by potential modifications of the simple circuit and wanted to increase the subpar bass response of my Sennheiser HD-280 Pro headphones.
After spending days reading tutorials, message boards, shopping for parts, and then tweaking a cMoy on a breadboard, I spent more than eight hours constructing my first hand built cMoy on protoboard. It didn't work. I spent another eight hours assembling a second (and functional) cMoy, later realizing I had forgotten just one wire on each channel of the first amp. In all, it took over 25 hours to build the same amplifier many others before me had built over the previous eight years.
Some months later, the first Bass Boost cMoy was born on a messy breadboard. Thrilled with the result, I decided to produce a few nicer versions of the amplifier for myself on professionally printed circuit boards and share the great circuit with fellow audio enthusiasts. The cMoyBB has since found owners in more than 36 nations around the world.
The cMoyBB can be electrically completed in under 30 minutes, saving you many tedious hours over building a regular cMoy. More importantly, the cMoyBB cannot be matched by other cMoys in terms of audio quality.
Why DIY?
It is important to me to promote engineering creativity and progress, thus, I am upholding DIY tradition and making the cMoyBB available to everyone. Music, or audio in general, is a subjective topic. I greatly prefer the sound of the cMoyBB over other entry-level amplifiers. Still, you may wish to experiment with different resistors, capacitors, jacks, enclosures, or something more exotic. I suggest just a few alternative components in the BOM, but building the amplifier yourself gives you the freedom to build a unique, top-notch cMoy with practically an unlimited number of options.
Will building a cMoyBB myself save money?
The cMoyBB is a high-end version of the cMoy. It was not meant to be cheap. A cMoyBB built to standard specifications will easily exceed $50 USD, plus the cost of any tools you may not own (not to mention your valuable time and labor).
DIY headphone amplification is for those who possess the interest and/or knowledge to build their own amplifiers. In other words, this project is not intended to save you money. It is always fastest and easiest to buy a preassembled amplifier.
Where is the schematic?
I would like to share the cMoyBB's schematic. However, the cMoyBB cannot be properly reproduced without its custom printed circuit board (PCB). Achieving proper signal characteristics and decoupling is essential to the amplifier's performance. These features cannot be reliably implemented with protoboard or homemade, single-layer PCBs. The cMoyBB's PCB has undergone numerous revisions and analog signal integrity analyses. I specialize in high frequency analog circuit design; amateur PCB designers (even other electrical engineers) usually lack the knowledge to design a PCB with equivalent performance. If I were to release the schematic, cloned versions of the cMoyBB would undoubtedly produce inferior sound quality and tarnish the amplifier's excellent reputation.
As explained above, it wouldn't be worth anyone's time to try to copy the circuit by hand. The cMoyBB v2.02 PCB is priced cheaply (barely more than protoboard) and is absolutely necessary to achieve great sound quality. For these reasons, I choose not to reveal the schematic. You are still welcome to ask circuitry-related questions.
Skill and Knowledge Prerequisites
Although this guide should single-handedly provide you with the necessary information to build a cMoyBB, I highly recommend browsing through Tangent's cMoy tutorial and Chu Moy's original article. The cMoyBB is a derivative of the original cMoy design. Consequently, I will not bother repeating Tangent's exceptional work. If you are not already skilled in soldering, definitely check out Tangent's tutorial videos and practice before you begin.
Usage Policy
This project is intended for personal use only. Commercial usage of this DIY Guide and/or the bare cMoyBB circuit board is strictly prohibited without prior written authorization. cMoyBB is a trademark of JDS Labs. As such, the cMoyBB circuit board may not be copied or cloned.
Proceed to Assembly Guide