Back in November, we took an in-depth look at Traffic Independent Synchronization (TIS), a Blackfire Research technology which allows precise syncing of your wireless speakers. Today, we’re going to look at another Blackfire technology: Real-Time Packet Management (RPM) for streaming music to your speakers without excessive buffering.
We’ve all been there: you finally find that perfect song only to click on it and have the “spinning pinwheel of death” appear. Or worse still, trying to watch TV with wireless speakers that play several seconds out of sync – like a bad art-house dubbed foreign movie. Those are the effects of buffering.
Some wireless audio systems are so susceptible to signal interference that they compensate by pre-loading (or buffering) the signal data before they start to playback. Without buffering on these systems you’d hear sporadic gaps in the audio (called drop outs) due to the lost audio data. So how much data is needed to buffer in order to prevent gaps or drop-outs?
Today’s most popular wireless speakers uses conventional WiFi protocol which has to queue the data. When you select a playlist from your smartphone or tablet, it takes several seconds for the first song to fill the buffer before it begins playing. While that first song is playing, the system is already buffering the next song to minimize gaps between songs. This is fine until, of course, you change the queue (say, by hitting “play next”) before it can re-buffer. In which case, hello spinning pinwheel. Also, because of this delayed playback, you won’t be able to use these popular wireless speakers as a soundbar with your TV without a wire (i.e. an optical cable connection).
Real-Time Packet Management (RPM) is the Blackfire solution to buffering. RPM uses a special multipoint, real-time feedback signal from each speaker to monitor the effect of noise on the audio data stream. This allows a much shorter queue and requires much less buffering.
Want to hear the difference for yourself? RPM is embedded into all Blackfire enabled products, including The Harman/Kardon Omni Series and Pioneer MRX Series. Next week, we’ll look at Dynamic Stream Balancing (DSB) and how it works with TIS and RPM to create FCP: Firecast Protocol – Blackfire’s solution to conventional wifi protocols.