SDC – Sub Delay Checker

stop guessing - start measuring. you are a touring dj or a sound engineer on a tight schedule and a tighter budget. sdc gets your subs and tops aligned with the gear you already carry. WHAT YOU NEED - iPhone, iPad or Mac - an audio interface, or the usb card already in your mixer - a measurement microphone run the output and the microphone through the same interface. that shared sample clock is what makes the timing trustworthy, and sdc warns you when the two don't match. a built-in phone mic is fine for a rough look - a measurement mic on one shared clock is what you want when it counts. HOW IT GOES 1. hook it up and pick your input and output channels 2. hit start - a level check runs first so you can set your gain 3. the app walks you through it: mute the sub and it measures the top, mute the top and it measures the sub 4. read the answer WHAT YOU GET not a chart to interpret. a sentence to act on: "increase sub delay by 0.8 ms to reach phase alignment at 100 Hz" and the numbers behind it: arrival times for top and sub, the difference in milliseconds and in metres, how far the phase is off at your crossover, and how high up the two stay inside the 60 degree corridor. tell sdc if your dsp or sub runs a 180 degree polarity flip and it aims at the right target angle. set the value on your mixer or dsp. done. THE ROOM, IF YOU WANT IT after a measurement you can add a room sweep to the same export. sdc plays a reference sweep, records the response, and hands you both files as a stimulus/response pair for whatever analyser you already use. no analysis happens in the app - that part stays in your tool. for sweeps, use an interface. a phone's built-in speaker and mic don't share a tight enough clock, and the recording gets rejected on import. BUILT FOR THE FIELD - a guide inside the app: signal chain, mic position and height, the full workflow - an ear protection warning before anything loud plays - works with what you have: usb interfaces, mixer usb cards, wired measurement mics YOUR DATA STAYS YOURS no account, no network, no tracking, no ads. every export lands on your device and goes nowhere unless you send it yourself.