MXL AC-404 USB Conferencing microphone review
September 2012 - With video conferencing and Voice based interfaces & VOIP communication, we continued our reviews of several easy to use USB microphones targeted at this market. The unit we just finished testing was from MXL and was the AC-404 which is a commercial level performance targeted product for the office environment. This table use microphone has a 180degree microphone pickup and a non slip bottom for handsfree placement on a table. The table top microphone is an alternative to the use of a single person headset with boom microphone, so it can also be used by a single person for gaming applications.
Pro - easy to setup up under windows, clear sound capture, no additional software required, good sensitivity, works for speech-to-text
Con - very sensitive, is recognized as a USB codec device rather than Microphone by Windows
Overall - Solid product for the price point. This is a strong high reliability mid level product for small to mid-sized conference rooms, does well with multiple people in the room and supports headphones for private calls.
The speakerphone comes in a simple box with an instruction sheet and includes a free copy of Oovoo video conferencing software. The USB device requires no drivers and is auto-recognized by both Win XP and Win 7 as a USB AV device with built in codec. The device comes with a long Usb cable that will work with an extension cable (up to 15' in length) similarly to the standard AC-406 speakerphone.
The microphone from recording specialist MXL, uses a combination of 3 mics that provide a full 180 degree coverage. The sensitivity can be set very high with both Win 7 and Win XP. For normal use, it should be adjusted down to get a good clear coverage of the voices without picking noises such as chairs, pens and keyboards. As the microphone pattern is a half circle, positioning the microphone on the table is a key. The non-slip backing keeps the microphone firmly in place in normal operation. The sensitivity can be adjusted to support multiple microphones in the same room, the layout of them on a large conference table requires some adjustment to get 3-4 units in one room, but when completed, delivers high quality results to the end point.
The sound quality from the headphone jack is very clear and supports both wireless base stations plugged in or wired headsets. There is no additional latency when testing with Skype or Google+ for voice or video when hearing through the speaker.
The microphone does a good job of damping vibration from the table from being picked up with the cushioning on the bottom of the unit. With multiple people in the room, the microphone did a good job of adjusting to the various voice levels and locations in the pickup area. Most of the people were a standard 2.5'-4' from the unit and were picked up without ny issues.
Overall, the product worked as a good office microphone for VOIP applications. It can double in those cases as a entry mike for speech to text use. The clarity of the microphone was good enough to not require retraining of the software to recognize the voice that was setup with a headset and boom mic. It worked well with a large number of different voices (6 different people tested) and the results were all uniformly high. The microphone can also be used for podcasting applications, however care must be taken to adjust the sensitivity to avoid background noises from footsteps, typing, and other office noises from entering the sound channel. The microphone was NOT tested for music recording as the USB interface was identified as a USB Codec Device and did not auto-recognize as a microphone source by Cakewalk Sonar 8.5 or Sonar X1, nor by Sony Acid Pro 7.
The unit was tested with dual and quad core Intel processors using Win XP SP3 and Win 7. The devices were tested in standard USB2 connections with and without a generic un-branded 15' USB extension cable. Programs that were tested were Skype, Google+, standard Google voice search and Dragon Speak 10 Professional by Nuance. The environment was a standard 10x12 office with window and single door and a larger 10 person conference room with center table an 1 glass wall.