It sounds like the bass frequencies are simply too low to be reproduced on the small speakers. Increasing the volume of the bassline, esepcially if it already sounds good on a better sound system, would only serve to cause distortion and would still be unlikely to help the laptop sound situation.
One possibility might be to mirror the bassline, but pitch shift it upwards a few steps so that it sits in a frequency spectrum better supported by those speakers. One way to accomplish this would be to open the audio file in Waveform view and use the Edit > Frequency Band Splitter tool to break out the low frequencies into their own file. I’d probably draw out from 0Hz-120Hz. Then use Effects > Time and Pitch > Pitch Shifter to increase the pitch a few steps. I would start with 5 which should create a nice harmony, or 12 which would raise the pitch one octave. Be sure to select High Precision mode.
Then, insert your original audio file and the pitch shifted bassline into a new multitrack session with each clip on a separate track. You can adjust the level of each track until it sounds better on the low-quality speakers. (Be sure to listen on good speakers as well, so you don’t overdo it for those folks with quality sound.) Once satisfied, mix it down to a new file and replace the music clip in your video project.
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Durin Gleaves
Adobe Audition