Sound Drop Outs at High Volume

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Sound Drop Outs at High Volume

Classic This information is applicable to the L1® Classic

From Bill-at-Bose[1]

Hilmar[2] and I looked into sound dropouts further to find the root cause, and found the rather subtle issue that, depending on the wire gauges and how the wires were paired in the cable, loud bass signals (in the speaker pair of wires) in extra long cables could capacitively couple into the sensing pair of wires. When it happened, the L1 "thought" you were changing your B1 Bass Module configuration and would mute.

So we looked at capacitance per foot with different wire guages, and with twisted vs untwisted pairs in the same cable, and looked at our sensing algorithm, and did two things to solve the problem:

We had Mark at Audiopile.net send us some samples to our new spec, we checked them, and they worked well. This gave a method for our customers who needed a long B1 cable to get one that worked.

The second thing we did was redesign the L1 software so that it could "filter out" the effects of momentary crosstalk and not cause the problem. That way future L1's would not have the issue.