I’m one of those types who likes to avoid wireless if at all possible and I usually shake my head wondering why when a client or artist insists on using an RF mic when they never wander more than about five feet in any direction. So last year when Alto Professional announced its Stealth Wireless speaker system, I initially wasn’t too impressed. In most portable sound systems, adding another component (and level of complexity) just to replace 25 feet of cable feeds from a stagebox or snake to the mains just didn’t seem worth the extra effort.
Eventually, I decided to check out the Stealth system, and although I still don’t feel I need a wireless feed to replace a couple short powered speaker lines, I definitely warmed up to the advantages of this problem-solver.
Enter the Stealth
Stealth Wireless system consists of a dual-channel transmitter and two single-channel receivers. (additional receivers are also sold separately for creating more elaborate setups). Front panel controls on the transmitter face include a stereo/mono input switch, two rotary trim pots for attenuating the left/right input signals and an RF channel select button with LED display indicating channel number. The transmitter’s rear panel has two balanced combo inputs for either XLR or 1/4-inch TRS feeds from your console, two permanently attached swiveling antennas and a 12 VDC power input for a 12 VDC wall wart supply.
The receivers are about size of a cigarette pack, and have a permanently attached swiveling antenna, channel select button and LED display, power switch and LEDs that glow to indicate RF and audio signal presence. Other switches include a three-position squelch switch that sets a noise limit threshold and a Left/Right selector that determines whether the unit is fed from the left or right outputs of the transmitter. At the base of the receiver is a balanced XLR audio output jack and a DC input for a 12 Volt power supply. Two 18-inch, stand male-female XLR cables come with the system for connecting the receivers to the speakers, or you could substitute your own.
All three components — transmitter and two receivers — use identical power supplies, so there’s no confusion on which one powers which unit. And regarding power, one appreciated touch is that all the supplies have eight-foot cables, so these can easily reach the floor when feeding a powered speaker on a tall tripod stand.
The receivers have a couple of mounting options. Both include self-adhesive hook and loop fastening strips for easily mounting to any speaker, as well as an M10 bolt that drops through a hole in the receiver for attachment to a standard unused rigging point. Alternatively, the lightweight receiver could be taped to any surface on the speaker or simply wedged under the handle of most speakers.
Operations
Setup and operation are fairly simple. Connections are straightforward, so it’s mostly plug and go. Stealth operates on any of any of 16 user-selectable channels in the 610 MHz to 640 MHz UHF range, although the exact indication of what these frequencies are is not so obvious. There is a chart on the Alto website, but it’s not in the user manual or printed on the bottom of the transmitter. So if you need to know that Channel #3, for example, is 617.650 MHz for the left and 618.350 MHz on the right, you might want to print out a copy to keep with you.
Speaking of frequencies, setting the RF channels is an entirely manual process. You select the transmitter first, then set the receivers to the same channel. There is no auto-scanning function that automatically seeks a clear frequency, so having that frequency chart and avoiding any channels your other RF gear is using is a good idea.
Stealth operates at 10 milliwatts, so maintaining a clear line of sight between the transmitter and receivers is essential. Usually FOH speakers are well above any audience obstructions, but the transmitter often needs to get some height. At one of my first outings with the Stealth, feeding a set of delay speakers at a huge church show, I needed to get the transmitter up higher for a clean path to the receivers. Normally I would have extended the antenna feeds, but with the permanently attached antennas, I wanted to mount the Stealth atop a tall lighting stand. The transmitter doesn’t have any threaded holes or places for attaching a mount, so it was gaffer-taped to the stand. Not pretty, but it did the trick.
I did have a few concerns because Stealth is a non-diversity UHF system — not quite the norm — but it operates between two fixed points‚ unlike moving performers on stage with mics or IEM’s and other performers moving around them. However, for this reason, the non-diversity wasn’t an issue and I had no problems in this regard.
On the Road
One of the gigs where I truly appreciated Stealth Wireless was for a film program at a local performing arts center, where the video projector was set up in the center of the venue. Laying and dressing 200 feet of audio lines would have been no fun at all. In this case I took a line feed from the video source, took it directly into the Stealth, and used the rotary gain trims to tweak the playback volume. Total setup and breakdown time was less than 15 minutes. Yeah!
On another show, I brought the Stealth along but didn’t need it until 10 minutes before the show, when the promoter asked if I could provide an audio feed for a videographer 75 feet away on the other side of the venue. I plugged in the stealth, brought two receivers to the camera op and checked their feed from the walk music. Another crisis averted.
The Verdict
I like this one. It’s an inexpensive solution in a lot of instances and actually performed as described. I didn’t encounter any wireless problems but wasn’t applying the system in any RF-crazy environments, applications requiring dozens of simultaneous wireless channels or guitar players showing up with unannounced mystery RF units at the last minute. Sure, I would have liked more elaborate channel operations, higher powering, auto-scanning, removable antennas and more mounting options — and maybe Alto Professional could consider these for a future “plus” unit. But for now, this is a useful system that’s priced right and works fine in a lot of pro applications.
At a Glance
Going Stealth
Go wireless with your main FOH system or delay speakers and forget about taping down and removing feed lines before/after a gig.
Manufacturer: Alto Professional
Pros: Fast, simple operation; affordable pricing.
Cons: Needs frequency ID’ing; no mount option for transmitter.
Street Pricing: $399; expander pack with two extra receivers is $199.
More Info: www.altoproaudio.com
