MixTester - A/B Music Testing Platform

In the fast-paced world of music production and audio engineering, clarity is everything. Whether you are a seasoned mixing engineer sending final revisions to a demanding client, or a bedroom producer collaborating with bandmates online, getting actionable feedback is often the hardest part of the job. Traditional methods of sharing audio files—like attaching MP3s to long email threads, uploading to generic cloud storage folders, or using standard music streaming services—are fundamentally flawed for critical listening. These platforms compress audio unpredictably and introduce jarring pauses when switching between tracks, completely destroying your auditory memory and making it impossible to genuinely compare the subtle differences between a "vocal up" mix, a different master buss compression setting, or an alternative arrangement.

MixTester solves this massive pain point by bringing an essential studio workflow directly into the web browser. Our platform is meticulously designed around a custom, gapless playback engine utilizing the Web Audio API. This means that when you are A/B testing two tracks, the playback switches instantaneously at the exact same sample position without a single dropped frame or click. It is just like soloing different channels in your DAW (Digital Audio Workstation) or engaging an A/B hardware switch in a professional recording studio control room. This level of precision is absolutely critical for evaluating minute EQ (equalization) adjustments, testing the decay of reverb tails, or finding the perfect vocal level. By eliminating the latency of switching files, MixTester allows you to hear the actual differences in the audio, rather than the distraction of the silence between them.

Furthermore, human hearing is notoriously unreliable and easily swayed by bias. We naturally perceive louder audio as "better," punchier, and more exciting. To combat this, MixTester incorporates automatic loudness matching via integrated LUFS (Loudness Units relative to Full Scale) analysis. With a single click, you can normalize all uploaded versions of a song so they play back at the exact same perceived apparent volume, ensuring you are comparing the actual frequency balance and dynamic range of the mix, rather than simply which file hit the limiter the hardest. Combine this with our True Blind Testing mode—which anonymizes filenames and randomizes the track order—and you have a foolproof system for subjective audio evaluation. Your clients and collaborators can leave timestamped comments directly on the timeline, pinpointing exact moments that need attention. Stop guessing what your clients mean and start finishing songs faster with MixTester, the ultimate A/B music testing software for audio professionals.