"Everything You Always Wanted to Know About Audio Electronics..." Part 2

Our resident electronics expert, Duncan Gray, is back to answer your audio electronics questions! Duncan and I recorded two hours of answers last week to the questions you asked in the original "Everything You Always Wanted to Know About Audio Electronics..." post. So to spare you the tedium of digging through 120 minutes of audio to find the answer to your questions, we've split our conversation up into smaller, more easily digestible podcast. Stick with us until the 33 minute mark, where we answer my favorite question so far that gets to the heart of the amazing relationship between audio and analog electronics. Download the mp3 or listen on iTunes . Subscribe to the DIYRE podcast In today's 45 minute segment we cover: "What troubleshooting process do you recommend when your PCB-based project isn’t working?" "What audible impact does input/output impedance have on the connected equipment. The effect it has upon the amount of voltage transferred is clear, however a more comprehensive explanation on how impedance can alter the sound of interfaced equipment would be hugely appreciated." When impedance can be negligible and when it can have a huge impact on sound. "Capacitors have been causing me headaches for a while now. In pedals for guitars, tone circuits for guitars, audio paths for pre’s, and so on, it always seems like folks go the extra mile to use film caps. Why? Isn’t a cap a cap a cap? Putting aside electrolytics for the moment, and voltage limits, why would anyone use one style (ceramic, mica, polyester, polypropylene) over another for audio purposes?" Why Duncan would avoid ceramic caps in the signal path "like the plague." Duncan ranks types of film capacitors in terms of their suitability to audio. "What parts are most/least to susceptible to heat damage from soldering? Using a hemostat to protect your components while soldering. Straight 5" Hemostat (Amazon affiliate link that benefits DIYRE.) "What do you think the top five safety rules are when building audio gear , whether tube or solid-state?" Which voltages are dangerous? Which are fatal? How to protect yourself from the circuit, and how to protect the circuit from you. "Can you clarify and explain the correlation between audio frequencies & amplitude, and their electrical counterparts current, voltage, and resistance… In other words what does a change in resistance, current, or voltage do to sound waves." The "magic of math": how sound and analog electronics are deeply analogous. Sound and AC voltage: same concepts, different medium Using the concept of "silence" to better understand electrical "ground."