Review: Belkin Universal Microphone Adapter

Pros:  Delivers strong audio under high-gain situations, acceptable audio under low- to medium-gain situations.

Cons:  Initially confusing labeling and LED indications, limited functionality, full retail price too high (though street price at some merchants is acceptable for specific users).

Review: Belkin Universal Microphone Adapter

In October of 2003, Belkin unexpectedly introduced the Voice Recorder, a $49.99 peripheral that uses a built-in microphone and speaker combination to transform a third-generation (3G) iPod into a digital voice recording device. One month later, competitor Griffin Technology announced iTalk, a lower-priced alternative with all the same features, and several others, including gain control, support for external microphone input, and headphone jack output.

Arguably in response to Griffin’s upcoming product, Belkin recently released a device that could either be viewed as an alternative or companion accessory to the Voice Recorder: the Universal Microphone Adapter, which at a $39.99 suggested retail price discards the built-in microphone and speaker combination in favor of two ports for external input and output devices.

Having recently completed testing of both of Belkin’s devices and Griffin’s iTalk alternative, we’re ready to share our conclusions with you. Depending on your needs and the recording hardware you already own, you may find that the Universal Microphone Adapter (UMA) has a feature that suits your tastes – or you might discover that the iTalk is a better – if slightly more expensive package.

The iPod’s Current Limits: Voice Recording, Only

As you may know from our review last year of the Voice Recorder, version 2.1 of the iPod’s system software added limited but easy-to-use recording capabilities to the 3G iPod. If you want to know how the recording interface works, take a look at our Voice Recorder review for photographs and a description of the menus. (Users of the iPod mini should also note up front that the mini does not support recording, most likely because of the mini’s smaller battery and the power consumption requirements of the recording peripherals.)

Significantly, by virtue of the iPod’s low 8 KHz monaural sampling rate and the old-school WAV file format, audio recording is limited to voices rather than music, and thus far the iPod’s only recording peripherals have permitted the use of monaural microphones rather than stereo line-quality inputs. Perhaps because of the iPod’s current limitations, and equally due to the lack of competition against Belkin’s earlier Voice Recorder, the need for enhanced microphone quality hasn’t come up much prior to now.

How the Universal Microphone Adapter Works

The Universal Microphone Adapter is an unusual product in the sense that it doesn’t really do anything by itself: it is simply a white plastic shell that encompasses two ports, a three-way switch, and a multi-colored LED indicator. Unlike the Voice Recorder, no microphone or output device is in the package. Instead, the UMA’s ports allow you to attach your own input and output devices, while the switch and LED work together to help you adjust the “gain” on your microphone.

Gain in audio is like focus in vision: if the gain is properly adjusted, the voices stand out from ambient background noise and the important audio is easier to hear.

Review: Belkin Universal Microphone Adapter

After plugging in your microphone and pressing “record” in the Voice Memo menu, the UMA’s light will glow green, yellow or red to indicate whether the device’s current gain switch setting is appropriate given the distance and volume of the audio source from the mike. If the gain is off, the audio may sound muddy, with potentially equal ratios of noise and voice. Alternately, the microphone may be so miscalibrated in a large room that you won’t pick up the voice you’re trying to record at all. Users at great distances and/or in large rooms are supposed to use the high gain/low volume position, while dictation and closer range users are supposed to use the low gain/high volume position.

Belkin made two counter-intuitive labeling choices with the gain control functions of the UMA. First, it marked the device’s switch only with a microphone icon and what looks to be an increasing volume level from left to right, but the level actually indicates the gain level, which changes inversely with the volume level. Second, although it uses green, yellow and red lights, it turns out that green isn’t “go” or “great,” but rather “gain is too low,” and yellow isn’t “caution” but rather is close to the optimum gain level. Manual reading, experimentation and proper use of the LED therefore become important when using the UMA, factors that aren’t as much concerns with Griffin’s automatic gain control feature in the iTalk.

Even when you’re using the LED properly and think you have an optimum gain level, you might be focusing on the wrong voice.

This could happen if you sit in a lecture hall and attempt to record the lecturer, but instead pick up only the comments of the people sitting in front of you. For this reason, it would be extremely helpful to have the ability to preview exactly what you’re recording with headphones while you’re recording it, something that the two-port design of the UMA suggests would be possible, but unfortunately the UMA can’t record and output audio at the same time. (For the record, Griffin’s iTalk can’t do this either, but then, it doesn’t have two separate ports that would suggest it’s possible, and its automatic gain control works quite well without user intervention.)

Overall Performance

Headphone output from the Universal Microphone Adapter is unsurprisingly identical to the iPod’s standard headphone output. Lacking a speaker, the UMA cannot be used as an iPod alarm clock or a music player like the Voice Recorder or iTalk, and thus its major functionality is really just voice recording.

While we were initially concerned with the quality of the audio that came off of the Universal Microphone Adapter – primarily the noise to voice ratio – we quickly realized that this was more a function of proper use of the gain switch than anything else. When properly recorded, audio sounded about as good as it did on Griffin’s iTalk, though it was generally harder to get a proper recording on the UMA than on the iTalk because of the iTalk’s automatic, rather than manual gain control system.

Review: Belkin Universal Microphone Adapter

The lack of gain control was considered by some Voice Recorder users as a significant omission, and the UMA’s three-position switch and LED come a substantial way towards remedying that concern – if you read the manual properly and understand them. If this seems too intimidating for you, it’s worth noting that in our testing, the LED was especially unimportant in a large room, high gain situation – we could just set the UMA up and go.

In fact, we felt that the UMA worked best under such high gain conditions. Using the same inexpensive testing microphone on both the iTalk and the UMA, we found that the UMA made louder recordings and picked up more voice at a greater distance than the iTalk, excelling specifically beyond 30 foot testing ranges – high-gain performance was roughly equal before that. However, under dictation and conversational use, the iTalk’s automatic gain generally delivered better-sounding and more balanced audio.