Team D0: Sequence Delay Pedal

Our biggest risks remain that any of our components do not function. Thankfully, the Daisy Seeds have arrived, and they have no apparent issues, so we have a microcontroller and a backup. However, we still have more components that have yet to arrive. We have configured a list of materials that we will order, and we plan to test them rigorously so we know that they function as intended.

This week, our design has stayed more or less the same. We have configured some finer details, including the size of the PCB that will be housed in the pedal.

Our schedule has not seen significant changes. Some issues have pushed work into slack time, so we are somewhat behind schedule, but our order of operations remains the same.

 

Part A (Chaitanya Irkar):

​​When designing and conceptualizing our pedal, one of my primary initiatives was to deliver a compact, easy-to-use product that could be enjoyed on a global level. We understood that not all consumers of our product will have access to the same high-quality resources available to us as CMU students. Emphasis on portability removes an physical restrictions for transporting or even delivering the product to individuals around the globe. It can also easily be shared by bandmates, gifted to friends, and easily stored in any environment, making it catered to individuals of all musical backgrounds. We also spent a significant amount of time designing our pedal interface (knobs, switches, buttons) to make it easy to adjust and view pedal settings. The only “complex” component of our design are the pcb board and Daisy microcontroller. These components will be hidden inside the pedal casing, limiting access to any harder-to-use parts. While our product does promote usage amongst people all over the world, it does require a power supply which could serve as an obstacle for users in areas of unsteady electricity. Such a factor is difficult to mitigate in the context of a guitar pedal design due to the necessity of a power supply to operate. However, we hope that our basic user-interface and other design choices will compensate for any other shortcomings outside of our control.

 

Part B (J. Frantz): 

Our pedal will allowsfor users to subdivide the repeat period into either four or three portions, matching how most contemporary music uses binary or ternary meters. These encompass the most simple divisions of time in music, and there will be a wide range of customization granted by allowing the user to select a meter.

Notably, our pitch-shifting is planned to use 12-tone equal temperment tuning in order to calculate the intervals. This is a standard that is used throughout most contemporary music today, but this is not the only tuning system that exists. Microtonality is prevalent in genres like Indian classical music, but our pedal’s pitch-shifting will not account for this.

These simplifications are design choices made with a semester’s scope in mind. Our primary goal is to make a device that is useful for a wide range of musicians, and we wanted to keep our design simple enough. Allowing for a wider range of meters and tunings is a possible goal for further improvements beyond our capstone.

One important cultural factor to consider is that the general public would not like to be subjected to excessive noise. Therefore, in our delay mechanism, we will restrict the amplitude scalar for each successive delay to be not more than unity. This will ensure that the input sound will not grow exponentially loud and harsh for people in the vicinity.

 

Part C (Nick W):

The main environmental considerations for our project come in production and the energy efficiency of operation. For production the main concerns are the materials used, and how they are produced. Considering this, we are using mass produced interface parts, which don’t have much environmental impact, 3D printing our casing to minimize waste, and using a standard PCB manufacturer, but would likely search for an environmentally friendly manufacturer if these were mass produced. For energy efficiency, we can’t save power in many places since we need most components to be on while the effect is active, but we will turn off some parts such as the screen when the effect is off.

Currently, our most significant risks are the possibilities that the components we receive arrive broken or stop working during testing. We are addressing this by ordering extra parts to use in this case.

This week, we made many changes to our prior designs for the pedal. We settled on using rotary encoders for our dials instead of potentiometers, and we decided on a mechanism to control pitch-shifting. Pitch-shifting greatly increases our pedal’s functionality in a way that will be beneficial to our end users. Using potentiometers would limit our dials to controlling one parameter each, so we rejected that idea so that one dial could control pitch shifting for any of the sequence beats. We decided to use the delay time’s rotary encoder to change the pitch (in semitone increments) to whichever sequence note is selected among a set of switches. We also decided to allow users to mute the first note in the sequence, which we imagine could be useful and easy to implement.

Our schedule has more or less stayed the same. We are not behind on anything, and we anticipate having time to spare in case any of our components arrive late.

Part A (J. Frantz):

Our pedal will be a tool for making art, but there are still important safety issues to take into consideration. For starters, our pedal should be sturdy enough to withstand a person’s stomp. If our pedal were to shatter if someone presses too hard, it could send pieces flying and potentially injure someone. Also, it could expose our circuitry, which would be a shock hazard. Given that we want our pedal to be used indoors or outdoors, we want our pedal’s insides to be safe from the rain. So, we should ensure that the casing is water resistant.

Part B (N. Walker):

Our pedal should be usable by people from many different cultural and social backgrounds, and the most significant consideration for that is making sure anyone can understand how to use it. We cannot expect everyone who might use our pedal to speak the same language, but as it is an effects pedal for instruments, we can expect that they will understand basic musical terminology. Knowing this, we can use musical terms on the interface, such as “tempo” for delay time or using the terms for different beat patterns to control the delay patterns, and therefore make it as culturally accessible as possible.

Part C (C. Irkar):

By producing a single pedal, we provide an affordable alternative to expensive music technologies that have a wide range of functions that might not perfectly meet the needs of the user. A custom pedal allows us to cater to the needs of guitarists while reducing the cost of hardware, making it more cost-effective to produce and distribute. The compact design of our product makes it more portable, enabling musicians to easily transport our product and use it in an environment of their choosing. While the functionality of our pedal is our top priority, having a user interface that is straightforward and easy to use is something we will push heavily for. Our goal is to create a product that both an amateur and a professional can use. Considering these economic factors will mold our product into a user-friendly, affordable, and portable device that can aid any musician.