[Overview]
This item is a pair of ALTEC A5 professional theater speaker systems, released by ALTEC in the 1950s under the name “Voice of the Theater,” hereafter referred to as VOTT.
The A5 system consists of the H825 enclosure with an ALTEC 515 + 288 + N500C configuration.
The concept behind this theater project was to produce the highest-grade theater speakers, and their sound pressure, sound quality, and dynamic presentation continue to fascinate many audio enthusiasts to this day.
With the introduction of VOTT, these speakers spread widely among many theaters and private collectors, becoming a bridge between professional theater use and private ownership. It is well known that many venues switched from previous-generation Western Electric and Jensen systems to the VOTT series, represented by the A5.
H825 Signature Enclosure
Originally used as professional equipment in cinemas and similar facilities, the H825 enclosure itself has a rugged appearance with little decorative consideration. It is clear that it was designed around the concept of functional beauty, where the focus is entirely on the sound itself.
This pair uses the vertical-slit boards in the bass port openings, a symbolic feature of the early model type.
You can enjoy the outstanding ALTEC sound that matches its powerful, weighty appearance. This specification allows you to experience the realism and atmosphere of a theater as it was intended.
The cabinets are fully dried and are in an exceptionally open and resonant condition.
Equipped with the Earliest RWB Units
The units installed in this pair are the earliest type featuring the legendary RWB decals, meaning the red, white, and blue stripe decals.
For the low-frequency section, the system uses ALTEC 515 20Ω 15-inch units, which deliver an impressively extended, glossy, and rich low-frequency texture.
The history of the 515, which can be considered the predecessor of the well-known 515B, dates back to the Lansing era and is even longer than that of ALTEC’s 416 woofer.
For the high-frequency driver and horn, the system uses ALTEC 288 24Ω drivers. The glossy high-frequency sound produced through the throat horn is outstanding, giving the impression that even the smallest details of trumpet tones are reproduced without being missed.
The 288 also features the rare RWB decal, and its compatibility with the 515 is exceptional.
H805A Multicell Tar-Filled Horn
The horn is the H805A multicell tar-filled horn.
This is also a rare horn that is said to have been developed to accommodate the large magnet of the 288 driver. Its basic design is similar to the later 803B model, but this early version is a tar-filled type, with tar poured between the cells and the chassis.
This design suppresses unnecessary metallic resonance and ringing as much as possible, allowing the driver to demonstrate its original performance.
The network uses the N500C. It brings out the dynamic character of this mid-to-high-frequency-oriented unit configuration with confidence and stability, while achieving a natural connection between the ranges.
Composed of an extremely rare group of units that are seldom seen, this pair can truly be called a supreme item.
Due to its vintage age, the exterior shows signs of use such as paint peeling and scratches, but aside from that overall impression, it remains generally in good condition.
Both the edges and diaphragms are in exceptionally good condition.
As can be judged from the photos, the exterior is very clean. We have included as many images as possible.
Specifications
515 RWB 20Ω
This model was successfully put into practical use together with the 288 driver in 1942, alongside the development of a new theater speaker system that would later correspond to the A5 system. It is the predecessor of the 803/416 models.
Although the 803/416 are also high-performance units, this is an even higher-grade and rarer unit.
Diameter: 38cm / 15 inches
Serial numbers: 1387 / 1593
Voice coil diameter: 3 inches
Magnet: Alnico V
Maximum input: 35W, 50W peak
Impedance: 20Ω
Sensitivity: 98dB/W/1.2m
Frequency range: 20Hz–1000Hz
Recommended crossover frequency: 500Hz
288C RWB 24Ω
The 288 driver has a basic structure that is almost the same as the later 802 driver developed for the A7, but because the 288 was used in large theater systems such as the earlier A1X, its specifications differ significantly from the 802 in many areas.
For example, the 802 has a 1 3/4-inch voice coil, while the 288 has a 2.8-inch voice coil and a more powerful magnetic circuit.
The phase plug also differs: the 802 uses a double structure, while the 288 uses a triple structure. By adding one additional slit, the design minimizes high-frequency attenuation caused by the large-diameter diaphragm as much as possible, securing effective high-frequency characteristics.
Although the 288 driver was developed more than half a century ago, it remains an extremely refined driver unit that does not feel outdated in any way.
Type: Compression driver
Voice coil diameter: 7.1cm / 2.8 inches
Serial numbers: 2159 / 2217
Magnet: Alnico V
Impedance: 24Ω
Frequency range: 500Hz–16,000Hz
Recommended crossover range: 800Hz
Sensitivity: 115dB/W/1.2m
N500C 500Hz
The N500C is ALTEC’s first N500-type network, released in the 1940s.
It is used in combination with horns and other components to create a 2-way system with a 500Hz crossover.
Crossover frequency: 500Hz
Impedance: 12Ω
Enclosure Specifications
External dimensions, per side including horn:
Width 762mm × Height 1550mm × Depth 610mm
Weight, per side: Approximately 80kg
Total weight after packing: Approximately 200kg
Despite being a vintage item, not only the exterior but also the inside of the enclosures are in very good condition.
As can be judged from the photos, the exterior is very clean.
