AKG WMS420 Vocal Wireless Set Band A Handheld with D5 Dynamic Head

AKG WMS420 Vocal Set Band A: A Complete Handheld Channel With the D5 Head

The AKG WMS420 Vocal Set is a complete analog UHF wireless microphone channel supplied in the Band A configuration, built around an HT420 handheld transmitter fitted with AKG's patented D5 dynamic capsule and an SR420 stationary receiver. The box holds two receiver antennas, an AC adapter, a stand adapter and one AA size battery, and carries AKG item number 3416H00010, so the channel is complete on arrival. Audio runs 40 to 20,000 Hz within plus or minus 3 dB with typically 105 dB-A signal-to-noise and typically 0.8 percent total harmonic distortion at 1 kHz, and the receiver offers professional balanced XLR and unbalanced 1/4 in (6.3 mm) jack outputs, an audio clip LED, an RF control LED and an adjustable squelch level. Range is 98 ft (30 m) line of sight and up to eight compatible channels run inside one frequency band. Where the other WMS420 sets put a microphone on a body, this one puts it in a hand.

The Patented D5 Supercardioid Dynamic Capsule

Fitted to the HT420 is AKG's patented D5 dynamic capsule, and both halves of that description carry weight. Dynamic means the capsule generates its signal from a coil moving in a magnetic field, so it needs no polarising voltage, shrugs off humidity and temperature swings, and tolerates being gripped hard, passed between singers and set down heavily on a lectern; supercardioid describes a pickup pattern narrower than a cardioid whose deepest rejection falls at the rear sides rather than directly behind, which is roughly where floor monitors and side fills normally sit on a stage. That geometry is the practical reason a supercardioid handheld can be run louder before a system starts to ring. A monitor engineer aiming wedges at the rear sides of the microphone rather than dead behind it will get the most from it.

Supercardioid Technique and Feedback Margin in a Real Room

Getting the benefit of a supercardioid pattern depends on two things nobody tends to explain in a specification sheet. Because the pattern is narrower than a cardioid, a singer who drifts off the axis of the capsule loses level faster, so the technique is to stay in front of the grille rather than working across it from an angle; and because the null sits at the rear sides rather than directly behind, a wedge placed straight behind the singer is actually in a more sensitive part of the pattern than one placed slightly off to each side. Cupping a hand around the grille undoes the pattern entirely and is the most reliable way to make any directional handheld howl. A worship soloist or a small-club vocalist briefed on those three points gets several usable decibels of extra gain for nothing.

Band A, and Confirming the Carrier Range Before You Coordinate

Frequencies in Band A run from 530.025 to 559.000 MHz, the carrier range published in the per-band frequency table on AKG's SR420 receiver page, and this vocal set ships tuned within that band. Think of the range as the width of the shelf the radio link sits on: the handheld and the receiver are set to one channel inside it, and that channel is picked to steer clear of local television carriers and of any other radio microphone working the same room. Nearly 29 MHz of span is what makes up to eight simultaneous WMS420 channels practical, so a worship team with several roving handhelds or a theatre with a set of principals can stay on one platform. Both the transmitter and its matching receiver carry the band designation printed on the housing, which gives a volunteer or a stage manager a way to confirm that a later addition matches the system already installed. Before deploying in the United States the range should be checked against current spectrum rules, because post-repack reallocation restricts operation in parts of the former UHF range and 530 to 559 MHz sits where local coordination still matters.

The Stand Adapter, Powering and the Low Battery Warning

Included in this set and not in the bodypack sets is a stand adapter, which lets the HT420 be clipped into an ordinary microphone stand so the same channel serves a lectern, a podium or a static vocal position as readily as a roving one. Powering is one AA cell, either an LR6 alkaline or an HR6 NiMH rechargeable, giving up to eight hours, with integrated charging contacts so a rechargeable cell can be refilled in the optional CU400 charging unit without the battery compartment being opened; on a handheld that lives in a case and is switched on by a different person each week, a battery door that never has to be opened is a door that never breaks. A low battery warning indicator on the transmitter gives notice before the cell is exhausted. That combination turns battery management into a routine rather than a gamble.

Where the Vocal Set Fits, and Sharing a Band With Other Channels

Lead and backing vocals in small clubs and bars are the natural home, along with worship soloists, readers and announcements, school and college auditorium presentations, community theatre and cabaret, lecterns and podiums using the supplied stand adapter, karaoke and community entertainment nights, and award ceremonies or conference hosting. Rental stock supporting installed WMS420 receivers is the other steady demand. Because up to eight compatible channels operate inside one frequency band, a worship team with several roving microphones or a production with a handful of principals can stay on one platform and one band; the discipline that makes it work is to scan and set channels with the room populated rather than empty, since an audience carrying phones changes which channels remain clear. Set the SR420 output to suit a console microphone input or a line input, and the channel is ready to run.