epoch1970 wrote: > I only measured the ambient noise level once, with an iPhone... I did > not expect to have to disclose my findings here :) Anyways, there was > little public in the store, and the quietest place measured at ~34 dB. > In the "L" group, 1m away from the freezer I measured ~46 dB. Facing the > 2 doorless units, I read a bit less noise, except when doors where > opened to the street. > Near the doors, I measured up to 55 dB. Anyone rolling a shopping cart > in there makes ambient noise spike to well over 50dB. > > So it's all relative, inaccurate, and that's only one measurement I > took. But a difference of more than 10dB between the constantly quiet > and noisy places seemed significant to me. > > > Yes I can see the can of worms. But perhaps if the units are indeed > working more or less constantly, a mild noise reduction could be > achieved?
How many loudspeakers do you have in the store? Are they all supplied by the same amplifier? I would suggest the following relatively inexpensive approach: 1. Apply any practical soundproofing techniques to the refrigeration units themselves, in particular making sure that their noise is not being amplified by resonances in the floor or by the units touching one another. You need to ensure that the compressor units themselves do not overheat, so unfortunately you can't simply wrap them up with soundproofing material - however adding some sound deadening panels (of the type used in cars to improve the sound of in-door speakers) to the inside of the casing of the refrigeration units may have some effect for relatively little cost. 2. Use separate amplification for each speaker zone so that you can set the volume relative to the residual ambient noise in that particular area. Amps are cheap these days too! 3. Follow the earlier suggestion of reducing the dynamic range of the music programme material so that the music level itself remains more or less constant in each zone. This is likely to work out cheaper than any alternative approach & I suspect that it would prove to be just as effective. Good luck! Dave :) ------------------------------------------------------------------------ Golden Earring's Profile: http://forums.slimdevices.com/member.php?userid=66646 View this thread: http://forums.slimdevices.com/showthread.php?t=107617 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/mailman/listinfo/audiophiles
