The Bräuniger IQ Sonic Miniature Vario
-a product review

by Mark "Forger" Stucky

I’m a budget minimalist kind of guy and don’t fly with a fancy GPS-integrated flight deck, relying instead on a miniature variometer and altimeter watch.  Little has changed in the five years since I reviewed the then-current crop of miniature audio varios – the Mallettec Mini Vario and the now-discontinued Flytec Micro Vario.  Recently, Bräuniger entered the market with the futuristic-looking IQ Sonic, a vario that has one feature the others lack – a sink alarm.  The $199 Sonic, like the other miniature variometers, is marketed as a minimalist instrument or as a back-up vario for cross-country pilots.

The Sonic stands out with its slender curving translucent purple housing which is more reminiscent of an iMac than the black boxy mini varios of yesteryear.  It is larger than the other minis, measuring 3.5” long, 1.5” tall, and 0.75” thick ( 8.9cm x 3.8cm x 1.9cm ).  The Sonic is molded into a slight concave curve and the banana shape helps match the compound curves of modern helmets.  The vario comes with a small patch of velcro for fastening to the helmet and the latest models also include a short safety lanyard.

You power up the Sonic with a small three-position toggle switch giving you the ability to select up audio or up audio with a sink alarm.  Like the Mallettec, the Sonic advertises 200 hours of battery life but achieves it with a single $5.95 nickel-sized lithium watch battery.

With the older varios, to have a better understanding of their sink rate, pilots adjusted the audio threshold so the varios beeped slowly at their normal minimum sink rate.  In the presence of sinking air the vario would be quiet and with any lifting air the vario would increase its beep rate and/or tone.  This makes it more difficult to judge if you are gaining altitude in weak conditions and also makes adhering to speed-to-fly theory in sink a bit problematic. A sink alarm with an adjustable threshold helps mitigate both of these issues.

By virtue of having a sink alarm, the Sonic up audio beeps – not in the presence of lift – but in the presence of climb.  The sink alarm is user adjustable from –20 to –1000 fpm.  The pitch of the solid tone increases in depth as the sink rate increases above the threshold.

Unlike previous minis, the Sonic has the nice feature of adjustable volume.  At maximum volume it is not quite as loud as the Flytec but sufficiently loud so that it can be mounted away from your ear.  The faint Mallettec requires an “in the helmet” mounting which is aerodynamically clean but also attenuates the sound of the wind and other pilots’ voices.  I mounted the Sonic to my harness and the volume was more than adequate.

The volume, sink alarm, and zero-point thresholds are adjusted using a jeweler’s screwdriver and making these adjustments requires unscrewing the back of the case.  The Sonic is factory calibrated and warns the user not to attempt to change the zero-point setting.  I found the Sonic zero-point was stable and, in fact, never had the requirement to change any of the factory settings.  For reference, the Mallettec also retains its zero-point setting for extended periods (months and months).

There is a fine line between quick response time and false indications.  You want a vario to register minute changes in climb rate but filter out false indications that can occur from momentary changes in air pressure.  The Sonic walked the line beautifully; responding quickly to real lift or sink but remaining silent while the Mallettec gave an occasional erratic beep.  When climbing, the beep frequency and tone increase as the climb rate increases.  There is also an audible “step” at +260 fpm to make it easier to discern a thermal worth spending time in.

Helmet-mounted miniature varios can suffer from a problem that is not seen with conventional control bar mounted varios, namely the appearance of phantom lift and sink caused by pitot pressure (ram air) changes due to swiveling your head.  This was a real problem with the Mallettec, any "wind in the ear" entered the static port and caused the vario to go silent (false sink).  Conversely, the moment I straightened my head I would be greeted with a sharp lift indication.  These false readings only lasted a few seconds but I found them irritating, especially while scratching in weak lift with other gliders nearby.  Due to head orientation, this problem is more prevalent for seated or paraglider pilots than prone hang glider pilots.  Regardless, the Sonic does a very good job of shielding the inner workings from momentary changes in pitot pressure and is thus, much more useable in this situation.

I found the Sonic audio very adequate but not as good as the Flytec which uses not only changes in pitch but also changes in the way it groups the beeps together.  This Flytec “Morse code” makes it amazingly easy for a pilot to figure his climb rate to within 100 fpm.  I don’t have the gift of a discerning musical ear and with the Sonic and the Mallettec I can only judge short-term relative changes in climb rates.

Overall, the Sonic offers a nice “total package” for a mini vario – responsive and accurate lift and sink audio, good volume, and modern looks.  For me, the adjustable sink alarm is enough to give the Sonic the award for “choice miniature audio variometer”.  I do, however, have a couple of recommendations for enhancements to give the Sonic even more appeal.  First, I would build upon the “beep group” idea used by Flytec so pilots could better discern their true climb rate as well as identify light, medium, and high sink rates.  Lastly, the inner workings are not as tightly packed as those of their competitors’.  Bräuniger could bundle up the electronics tighter and reduce unnecessary dead space, resulting in a significantly smaller housing.  A smaller, less obtrusive profile would make it easier to mount on a helmet as well as increase its resistance to getting knocked off.