PITTSBURGH — Based in Pittsburgh, SLB produces a regionally-distributed public radio program for children and families that often features live cut-ins from the field. We also conduct youth media workshops during which teens often record and edit phone interviews with community leaders.
Recently we’ve had the use of a JK Audio RemoteMix One phone interface/mixer. For both applications, this device proved to be a solid performer that was reliable, simple and a pleasure to use.
Before describing our tests, a quick product description is needed. The front panel contains a rotary pot, peak light and mute button to control a microphone connected via a rear-panel XLR jack. The front also contains a similar pot for use in mixing a line-level signal fed into a rear-panel stereo 3.5 mm jack. Trim pots are provided in recessed side holes to adjust levels to and from the phone. Rounding out the front is a headphone pot for volume control of the rear connected 1/4-inch headphones. The unit is powered by a 9 V battery and features a pushbutton on/off switch with light on the front panel.
This is not just a phone interface but a small mixer that can blend mic and line-level signals for transfer via the telephone interface. We immediately thought of applications such as live field reports with prerecorded actualities fed via the line input or remote broadcasts using this simple mixer or an external mixer sending its line output to the RemoteMix One line input.
All of this happens within a rugged 4 x 4 x 1.5-inch box that fits on a table or can be clipped to a belt. As we’ve come to expect from JK Audio, mic preamps are exceptionally quiet, the pots have a solid feel, and buttons and jacks are built to last.
As for the telephone interface, the RemoteMix One uses wired connections. While this may at first seem like a step backwards from their Bluetooth version, our evaluation convinced us that use of a wired connection makes sense for multiple reasons.
First, most of today’s phones — including iOS and Android devices — use a standard four-wire 3.5 mini-jack for headset I/O, eliminating age-old concerns about phone jack compatibility and ruggedness (JK Audio includes cables for this 3.5 mm jack as well as a one for a 2.5 mm jack designed for legacy three-wire devices).
Using the wired connection also is easier when setting up a phone interview — getting to the interface is as simple as inserting the headset plug (no more phone menu searches).
Second, and perhaps most important, with Bluetooth out of the picture audio need not be subject to its bandwidth limitations. This is important because virtually any iOS or Android codecs can be used (e.g., Skype) in lieu of a telephone call to move audio between source and destination. Such codecs also can be used via a computer in lieu of a smartphone.
We began our tests using the unit as a tool for teens to conduct and record oral history interviews with adults by telephone. Without reading the instruction manual, we grasped quickly that the RemoteMix-connected microphone and headphones were their means for interacting with the caller. They conducted their interviews comfortably; audio levels were reliable and clear. Recordings were made via the back-panel 3.5 mm stereo-out jack.
As with the company’s BluePack unit, its attention to a detail makes a difference here. The line-out jack delivers microphone audio in one channel and telephone audio in the other channel with outstanding separation. This means that interviewee audio can be isolated to remove local microphone noise (or inadvertent interviewer interjections). It also means that the interviewer’s portion can be captured in full fidelity for tape sync applications.
We continued tests by having an SLB field reporter call our studios via cellphone (to a landline connected to our studio board via a POTS hybrid) and a Skype-to-Skype connection (to a PC connected to our studio board by a Lynx AES16 card).
Both scenarios yielded remarkably clear speech. While Skype provided slightly better clarity, its increased latency made us favor use of the cellphone option. That said, it’s nice to have the Skype option for situations in which reliable cell connections may be difficult to maintain. Moreover, we suspect that codecs from other broadcast companies will yield better results.
We also tried passing music to the studio via the line-level input. While it was easy and effective to use the mixer, both the phone and Skype tests delivered (not surprisingly) music that was bit hard to listen to on the receiving end. That said, using the line input for brief music or recorded news actualities would be fine. Moreover, we feel certain that stronger smartphone codecs would allow passage of music more clearly.
We found two notes of caution. The front-panel mute button exhibits slight bleed-through at very high mic levels. Second, as with nearly all cellphones, there is a possibility of RF noise if the phone gets too close to another piece of gear. Neither issue affected our use of the unit but are good things to take note of to ensure success.
As a telephone interview interface, we now have a device that is robust enough for broadcast-quality recordings yet simple enough for teens to use. As a device for live cut-ins, we have the flexibility of mixing line-level and mic content as well as leveraging third-party codecs such as Skype. For a belt-worn portable device that lists for $315, the unit is a sensible addition for anyone serious about newsgathering, public affairs, and community outreach.
For information, contact JK Audio in Illinois at (815) 786-2929 or visit www.jkaudio.com.