Azden has set a new level in quality and performance with the SGM-250 Professional Dual Powered Shotgun Microphone. The SGM-250 was designed for video and filmmaking professionals to deliver broadcast quality sound at an affordable price. A completely redesigned microphone element drastically improves sensitivity, frequency response and signal to noise ratio. The all metal-alloy case provides rugged durability and strong resistance to RF. Its custom designed, slotted, acoustic barrel exhibits excellent super-cardioid directionality and side noise rejection.
A recessed switch area has been added to the body of the microphone for comfort and feel. The features here include a switchable low-cut filter to help reduce low frequency noise, a power switch for either battery or phantom power operation and an LED battery indicator. The SGM-250 can work off standard 48V phantom power or a single AA battery with virtually no loss in performance.
Measuring 250mm in length (about 10 inches) the SGM-250 is suitable for almost any filming situation. Long enough to capture great sound from a distance while mounted to a boom pole or on top of a shoulder cam, its still unobtrusive enough to be used on compact DSLR cameras.
The SGM-250 comes with a leatherette, zippered carry pouch, shock-absorbing mic clip with shoe mount and a foam windscreen.
In The Box
Zippered carry pouch
Mic Element: Electret Condenser
Freq. Response: 20Hz – 20kHz
Low-Cut Filter: Selectable @160Hz, 3dB/Oct
Polar Pattern: Super-cardioid
Dynamic Range: 115dB 48V phantom / 110dB battery
Sensitivity: -38dB at 1kHz (0dB = 1V/Pa)
Impedance: 120Ω (at 1kHz)
Max Input SPL: 132dB 48V phantom / 127dB battery (1kHz at 1% T.H.D.)
S/N Ratio: 77dB (1kHz at 1Pa)
Power Requirement: 11-50V Phantom or AA battery
Output: 3-pin XLR
Dimensions: 250mm x 21mm (9.84” x 0.83”) (Length x Diameter)
Weight: 160 g (5.65 oz)
Accessories: Shock mount, windscreen, carrying case
Phantom power is a DC voltage supplied through a balanced microphone cable and is used to power the electronics of the connected microphone. Most professional cameras, mixers and audio interfaces with microphone XLR pre amps have the ability to supply phantom power.
Most commonly, phantom power is supplied at 48V. This is the optimum voltage for Azden's microphones. It is possible that your connecting equipment supplies a different voltage and each Azden microphone has a recommended voltage range that can be used. Be advised that microphone performance will degrade with lower voltages and damage to the electronics could result when using voltages in excess of this range. It is recommended that you consult the manuals of any equipment you intend to use with the microphone beforehand. Please note that the warranty does not cover damage caused by using phantom power beyond what the microphone is rated for.
In general, if your Azden microphone does not have a battery compartment it will require phantom power to work. Some microphones have the ability to use a battery for power or phantom power, while others may only work on battery. Check your manual or the product page for your model on azden.com to be sure.
Phantom power is not used at all with lapel, headset and DSLR camera microphones. These microphones do need a power source, but it is a much lower voltage. This type of power is typically called plug-in power (PiP) and is usually provided on mini-jack inputs on cameras and wireless transmitters. Attempting to use phantom power on a microphone that need plug-in power will very likely result in damaging the microphone element.
All of these terms are used to describe a microphone’s polar or pick-up pattern. The simplest being omni-directional, which means the microphone will pick up sound equally from all directions.
Cardioid and uni-directional are two interchangeable terms that are used to describe a microphone that is most sensitive to sound coming in directly in-front of the microphone element (on-axis) but will reject some sound coming from the sides and nearly reject all sound coming in from behind. These microphones are better at isolating a sound source in a noisy environment and are best used on a speaking subject up close.
Super-cardioid is a hyper-directional pick-up pattern, which is very sensitive to all sound in the front of the mic element, and does a very good job at rejecting sound coming in from the sides. Sound sensitivity from the rear is somewhat reduced but not totally. This kind of directionality is found in many of Azden’s shotgun microphones and is best suited for focusing in on sound sources from a distance but can also be used up close.
Any of Azden’s microphones with a 3.5mm mini-jack output can be made to work with a smartphone or tablet using the HX-Mi TRRS Mic/Headphone Cable. Compatible Azden microphones include EX-503, EX-503L, EX-505U, EX-50L, ECM-44, HS-9, HS-11, HS12, CM-20D, SGM-990 and SGM-DSLR. Azden’s stereo microphones can work with the HX-Mi but only in mono, since mobile devices do not have stereo microphone inputs. These microphones include SMX-20, SMX-10 and SMX-5. Also available is the SGM-990+i which comes complete with an adapter cable to make it compatible with mobile devices.
A low-cut filter is designed to reduce the volume of low frequencies as recorded by the microphone. This can be handy to reduce low frequency background noise such as wind, HVAC systems or traffic. It can also be used to reduce increased bass response due to proximity effect.
The design of the filter is different depending on which microphone. On the SMX-10 for example, engaging the low-cut reduces low frequencies at 6dB/octave below 200Hz. On the SGM-250, the low-cut rolls off at 160Hz at 3dB/octave.
Azden’s microphones are not waterproof but should be able to stand up to a little moisture and light rain if exposed infrequently. If you must use your microphone in the rain, it’s best that you try to keep it covered.
Azden’s SGM line of shotgun microphones are designed for this application. The SGM-3416 and 3416L are Azden’s high performance shotguns, designed to deliver the high quality that any broadcast professional or filmmaker would demand. The SGM-250 and SGM-1X are both great choices for boom work or studio use and were designed with the budget-conscious filmmaker in mind. The SGM-PII and SGM-PDII are great choices for on-camera mounting, with their shorter barrels designed to stay out of view of the camera lens.
We recommend using standard alkaline batteries. We do not recommend using rechargeable batteries with any of our VHF and UHF wireless units, mixers or microphones. In general, rechargeables will not last as long as standard alkaline batteries.
When most people hear noise in their video recordings, they assume it must be the fault of the connected audio equipment. While this is entirely possible, it is not often the case. The most likely culprit is actually your camera’s low quality microphone pre-amp.
Why is your camera’s pre-amp not so good? Camera manufacturers tend to put their development dollars into the functions related to photography. Sound is usually an afterthought and unfortunately the mic inputs on most DSLR cameras are designed to be good enough to work, but are far from being a professional audio input.
Why is the pre-amp adding noise? A microphone pre-amp adds gain (volume) to a connected microphone. And all pre-amps have an inherent noisiness, called a noise-floor. Low quality pre-amps tend to have a higher noise floor and when gain is utilized to increase the volume of the microphone, it also increases the level of the noise floor. This usually manifests as a hiss or white noise being audible in the soundtrack of your video.
What’s the solution? Whether using one of Azden's DSLR microphones or professional XLR shotguns microphones with a 3.5mm adapter, the best options for better sound quality are to use an audio adapter/mixer (like the FMX-DSLR) or to use an separate portable recording device.
In both cases, these devices use better, higher quality microphone pre-amps and should reduce any inherent noise present in your video recordings.