How loud is a GENMAX generator? Its manuals say 57 to 77 dB at 7 m

How loud is a GENMAX generator at 7 meters?

Between 57 and 77 dB at 7 m and 25% load, by the manuals: the small 1,200 watt inverters at the bottom, the non-inverter GM12000ED at the top.

Seven meters is about 23 feet, a distance many generator makers use. A quarter load is light work, roughly a fridge and a few lights on a mid-size unit. The manuals write "dB" with no A; the product pages print the same numbers as "dBA", so they are treated here as A-weighted.

For the enclosed inverters, the manual figures fall like this.

Because every manual uses that same row, the whole range reads on one basis. Hold the figures up to a decibel chart by all means, but remember they describe a light load.

Why do so many GENMAX inverters list 62 dB?

GENMAX gives no reason. The fact is that 62 dB at 7 m and 25% load covers almost the entire enclosed range above 2,000 watts, from the 2,300 rated watt GM2800iSAC to the 11.5 kW GM13500iETC.

Inside that group the engines run from 145 cc in the GM3200i to 349 cc in the GM9000iET, and weights from 44.1 lb to 276 lb. A big engine loafing at a quarter of its output might sound much like a small engine working harder. That could explain part of it, though it is our reading and not a GENMAX statement. For a buyer the upshot is simpler: stepping from a 3,200 watt GENMAX to an 8,000 watt one costs nothing on the published figure. Size only buys quiet below 2,800 watts, where the GM1200i and GM2000i sit 4 to 5 dB lower.

Full load adds about 6 dBA

Only one GENMAX page gives the curve. The GM3200i lists 62 at 25% load and 68 at full load, both at 23 feet, in a line that reads "At 23 feet distance, 57 DBA with no-load, 62 DBA with 25% load, 68DBA with full load." No other page or manual prints a no-load or full load figure.

Six decibels is a big step. To the ear it comes across as roughly half again as loud, so for anyone running near rated output, say an RV air conditioner on a 3,200 watt unit, the 62 understates what the neighbors will hear. Our guide to inverter generators under $1,000 applies the same caution across brands.

Two product pages disagree with their manuals

Mostly the pages and manuals match, though two pages print a different noise figure, and a third gives two weights.

The manual figures are used throughout because they name the distance and the load. Where a page is the only source for a model, the model sits in a separate section below, unranked.

Xi and non-inverter models run 65 to 77 dB

The Xi models, mostly open frame inverters, list 65 to 74 dB at 7 m and 25% load. The two non-inverter generators list 76 and 77.

At 4,000 watts the open frame GM4000Xi lists 66 against 62 for the enclosed GM4000iSBEPC, which puts the case's worth at about 4 dB for that size. The GM4000Xi page repeats the figure: "it operates at just 66 dB(A) measured from 7m at 25% load."

Models left out of the ranking

One current GENMAX inverter, the GM5250iA, has no noise row in either its manual table or its product page.

The GM3500iAED and GM3500iAD pages say 62 with no distance or load, and the GENMAX download page offered no manual for either. Several other pages state a floor, such as the GM9000iEDC's "As Low as 62 dBA Noise with 25%loading at 23 feet distance", and those models are ranked on their manual figures instead.

Is a GENMAX quieter than a Champion or Westinghouse?

The published figures cannot settle it. GENMAX states 7 m and 25% load; Champion and Westinghouse mostly leave out the load, or both conditions.

Champion rates its enclosed inverters from "23 feet" without naming a load, and Westinghouse prints "as quiet as" figures with neither distance nor load on most pages. So a 57 from GENMAX and a 53 from Champion are not a 4 dB gap to count on. Our quietest generators guide sets brands side by side, the dual fuel generators and home backup generators guides do the same for larger units, and the page on decibel ratings across brands explains why the basis decides what a comparison is worth.