Air-O-Swiss 7135 Microbial Ultrasonic Humidifier Brief Description This efficient air humidification technology uses high-frequency vibration to generate a micro-fine mist. A fan blows the mist into the room where it immediately evaporates. The 7135 Ultrasonic humidifier requires little power, has a built-in hygrostat and an output regulator button. A replaceable demineralization cartridge ensures a hygienic, pure water mist, without limescale or mineral residues. When operated with the pre-heating function, the water is heated to 176 F / 80 C before it enters the nebulizer chamber. The mist exits the appliance at a comfortable temperature of 104 F / 40 C. This has the advantage that the room temperature will not fall, and additionally the water can be kept cleaner. The Air-O-Swiss 7135 ultrasonic warm mist humidifier also features Automatic and Sleep modes. Automatic mode maintains ideal humidity you select in relation to room temperature. When the Sleep mode is set, the unit shuts off after eight hours. Ultrasonic humidifiers require little power. A replaceable demineralization cartridge ensures a hygienic, pure water mist, without limescale or mineral residues. Ultrasonic humidifiers have a built-in hygrostat and an output regulator button.
Customer Review: Air-O-Swiss 7135, Good but not good enough…
I bought the Air-O-Swiss believing that for the kind of money I was spending I would be getting the ultimate in humidification technology. Well it turns out that’s true, however there’s one caveat. As others have mentioned here the hygrometer is not very accurate and it reads terribly low. When I compare the hygrometer reading of the 7135 against my other thermo hygrometers it (7135) reads about 15~20% too low. This wouldn’t have been a problem had Air-O-Swiss provided the ability for users to set the humidity setpoint from 0~100%. Instead they’ve provided an absolute lower limit of 40% RH which means in reality you’ll end up driving the room well over 50% when the unit is set for 40%.

I contacted Air-O-Swiss about this and the gentleman on the phone told me that it’s probably the #1 complaint they get about this model and the others which are similar to it. I believe I have figured out the source of the problem and have shared that information with Air-O-Swiss. If you feel like a boring engineering diatribe read on, otherwise I’ve said everything that’s useful for John & Jane Q Consumer.

In my opinion the problem with the unit is as follows. Relative humidity, the parameter controlled by this unit, is as its name implies, relative. The value indicated on the face of the unit is supposed to indicate how close to saturation (i.e. 100% RH) the air is at a given temperature. If the temperature of the air mass goes up while you keep the total amount of water vapor in the air constant the RH% will fall as the temperature climbs. Likewise if you keep the total amount of water vapor in the air constant while lowering the temperature of the air mass the RH% will go up. Stated simply, warm air can hold a lot more water than hot air.

This unit calculates the RH using two electronic sensors which are inside the main housing. One is a thermistor (negative temperature coefficient resistor) whose resistance varies as a function of temperature and which is read by the microprocessor inside of the unit. The other is a hygrometer, probably a capacitive type whose capacitance varies as a function of humidity. Readings are taken from the hygrometer and using the temperature reading from the thermistor a figure is calculated for relative humidity. This works really well so long as the sensors are accurate. We’ll assume the hygrometer is perfectly accurate. However the temperature sensor (thermistor) is not. Unfortunately it has been placed inside of the box next to various electronics and not too far from the heater which warms the water. The result is that the unit corrupts its own sensor readings by heating up the thermistor. You can prove this to yourself by doing the following. Plug the unit in from dead cold and compare the readings against a good thermo/hygrometer. Mine is within a few percent…allow the unit for run for a while and you’ll notice as time goes on it drifts further and further off reading RH% that are lower and lower until they level off at about 15~20% error (on the low side).

The fix for this would have been very simple, remove the thermistor from the internal circuit board and place it on a cord that dangles from the unit. Unfortunately this is not what they’ve done. I’m rather tempted to modify my unit as the over humidification is intolerable. The solution given to me by Air-O-Swiss was unacceptable. They told me to turn it off and on as needed!?!?! The whole point of having these fancy electronics is so I don’t have to…

In all other regards the unit is very good, low noise, warm mist etc…the automatic aspects of it however are terribly flawed as I’ve explained above.

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Metal health Customer Review: The rise and fall of Quiet Riot in a single album
THE BAND: Kevin Dubrow (vocals), Carlos Cavazo (guitars), Rudy Sarzo (bass, synthesizer), Frankie Banali (drums & percussion).

THE DISC: (1983) Originally 10 songs clocking in at approximately 41 minutes, this remastered version gives you 2 bonus tracks and almost 52 minutes worth. The bonus tracks: “Danger Zone” (unreleased studio cut), and a live version of “Slick Black Cadillac”. Included with the disc is a 10-page booklet containing song titles/credits/times, original artwork and additional black & white photos, a brief 3-page intro, and thank you’s. Recorded at The Pasha Music House in Hollywood, CA. Originally released on Pasha’s label, this digitally remastered version is on Sony/Portrait/Epic.

COMMENTS: Disco was officially out a few years prior. New Wave was popular. Hard rock was coming back in. To many, American metal was still a question mark in the early 80’s. The British/European invasion of heavy metal was in full force (Iron Maiden, Judas Priest and the Scorpions to name a few big acts). In 1983 though, bigger albums than Def Leppard’s “Pyromania”, Motley Crue’s “Shout At The Devil”, or Iron Maiden’s “Piece Of Mind”… was Quiet Riot’s “Metal health“. 6+ million units sold and growing. As quickly as “Metal health” rose (the first metal record to hit #1 on the Billboard album charts), the band fell from grace. DuBrow’s antics were fairly well documented (difficult to get along with)… with other bands as well as his own. “Metal health” was a solid album, and it’s still a classic… but, it hasn’t stood the test of time as well as any of the other albums mentioned above. For me, Quiet Riot was the definition of “pop” hair metal. “Metal health” created the standard formula that all successful pop/hair metal bands seemed to follow… 1. Some aggressive hard rocking songs (”"Breathless”, “Run For Cover”, “Love’s A Bitch”); a couple of hits (”Metal health“, “Cum On Feel The Noise”), and a power ballad (”Thunderbird”). Quiet Riot’s cover version of Slade’s “Cum On Feel The Noise” hit #20 on the Billboard charts (#5 on the pop charts), as the title track hit #31. “Slick Black Cadillac” had minor success on the radio as well. Cavazo’s “Battle Axe” is a short guitar solo - in the same vein as Eddie Van Halen’s “Eruption”. A brief history of the players is documented in the disc booklet - Quiet Riot being formed by guitar-god Randy Rhoads and singer DuBrow in the mid 1970’s without much success; Rhoads and bassist Sarzo leaving QR to play with now solo Ozzy; Rhoads killed in a plane crash; Sarzo returns with Banali joining on drums and Cavazo on lead guitar. Some truly great songs here - my favorites are the title track, “Don’t Want To Let You Go”, and “Breathless”. The ballad “Thunderbird” (though an ode to Rhoads) is musically weak. The bonus tracks - “Danger Zone” fits right in with the rest of the album (good stuff), but the live “Slick Black Cadillac” is absolutely horrible (sounds like an out-of-breath high school band doing a cover tune). The potential was there to continue (and more albums being released), but Quiet Riot never again achieved the success it had in ‘83. “Metal health” is a classic in the “pop” arena of metal (4.5 stars).

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