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Old 04-02-2013, 11:50 AM   #101
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I'm not sure I'd call 71dB @ 23 feet "silent"
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Old 04-02-2013, 12:19 PM   #102
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Al, that chart is a bit deceptive. The decibel scale is shown as arithmetic; however, the relationship among decibels is logarithmic. For example, a lawnmower's 80 decibels is much more than four times louder than a whisper's 20 decibels. The chart's distances between the decibels should increase the higher the decibel to reflect the loudness of the sound.
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Old 04-02-2013, 11:56 PM   #103
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You're right, Mark, but it illustrates the dB level well. IIRC, an increase of 10dB is double the sound level. In other words, 40 dB is twice as loud as 30dB.

EDIT: This site says 6dB doubles the amplitude, 10dB doubles the perceived loudness.

Twice, two fold, and a doubling . . .
Doubling of the volume (loudness) should be felt by a level difference of 10 dB − acousticians say. Doubling the sound pressure (voltage) corresponds to a measured level change of 6 dB.
Doubling of acoustic power (sound intensity) corresponds to a calculated level change of 3 dB.

+3 dB = twice the power (Power respectively intensity − mostly calculated)
+6 dB = twice the amplitude (Voltage respectively sound pressure − mostly measured)
10 dB = twice the perceived volume or twice as loud (Loudness nearly sensed − psychoacoustics)


http://www.sengpielaudio.com/calculator-levelchange.htm
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Old 04-07-2013, 06:58 PM   #104
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When I was standing in front of 32 speakers and playing through 700 Watts RMS of tube power that was sending it as 2 OHMs to the speaker boxes, it would shake the stage and you could feel it in your feet. I used to say I could take the starch out of my clothes.

The drummer had 12 cymbals and 11 drums. The guitarist had Marshall stacks that were so loud it could cut through you. I experienced loud.

I just don't want it coming from a generator.
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Old 04-07-2013, 09:32 PM   #105
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What???!!!???
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Old 05-07-2013, 08:42 PM   #106
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I can attest to phasor, they make great generators! We have a 3.5kw with sound shield in our camano, it's very quiet and just hums. We had one problem not really to do with the generator but, it would blow the capacitor so we had to move outside of the sound shield, but you probably won't have that problem unless your installing it in tight space like we had (lazzerette). I'll try to find you a pic.
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Old 05-28-2013, 11:14 PM   #107
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NorthStar Belt Driven Generator Head 10,000 Watt | Generator Heads| Northern Tool + Equipment

Belted to either a seperate engine or even belted to the main ?
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Old 05-29-2013, 02:21 AM   #108
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NorthStar Belt Driven Generator Head 10,000 Watt | Generator Heads| Northern Tool + Equipment

Belted to either a seperate engine or even belted to the main ?
"3480-3780 RPM gen operating speed" seems a tad higher than I operate my engine at. It is essentially the same unit and rating I run on my 18HP Miller welding machine though.
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Old 05-29-2013, 06:27 AM   #109
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"3480-3780 RPM gen operating speed" seems a tad higher than I operate my engine at.

Thats why the preferred engine RPM is matched to the gen head with a set of belts .

No problem sizing a belt/pulley setup for a 1200 or 1800 RPM engine .

Since the Gen set was working , just the engine died , the local truck reefer shop will have fine running takeouts for $300-$500 .

These are uaually Kubota or Yannmar and will have huge oil pans to operate un inspected for 10 days.
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