Altec Model 17 (604-8G in 620 Cabinet)

Name: Altec Model 17
Brand: Altec

1970s - 1980s

The Altec Model 17 is a highly regarded studio monitor and home audio speaker system that combines the legendary 604-8G coaxial (duplex) driver with the classic 620 cabinet. Considered by many enthusiasts to be one of the best-sounding speakers Altec ever produced, the Model 17 offers the convenience of a single-point source with exceptional coherence and musicality.

Specifications

Type	2-way coaxial (duplex) loudspeaker system
Driver	604-8G 15" coaxial driver
Configuration	15" woofer with integrated high-frequency compression driver and horn
Crossover Frequency	1,600 Hz
Nominal Impedance	8 Ω
Power Handling	50W continuous, 100W program
Sensitivity	98-100 dB/W/m
Frequency Response	35 Hz - 18 kHz
Cabinet Type	620 bass-reflex enclosure
Cabinet Dimensions	Approximately 28" H x 24" W x 16" D
Weight	Approximately 80-90 lbs per speaker

The 604-8G Duplex Driver

The heart of the Model 17 is the legendary 604-8G coaxial driver:

Woofer: 15" cast-frame woofer with Alnico V magnet
High-Frequency Driver: Integrated compression driver with 1.75" aluminum diaphragm
Horn: Small format horn integrated into the driver's center
Crossover: Internal crossover network at 1,600 Hz
Magnet Structure: Large Alnico magnet for both woofer and compression driver

The coaxial design places the high-frequency source at the acoustic center of the woofer, providing perfect time alignment and exceptional coherence. This single-point source design eliminates the lobing and phase issues common in multi-driver systems.

620 Cabinet Design

The Model 17 uses the classic 620 cabinet, which was specifically designed for the 604 duplex driver:

Bass-Reflex Design: Tuned port for extended bass response
Internal Volume: Approximately 6-7 cubic feet optimized for the 604 driver
Construction: High-quality plywood with internal bracing
Finish: Typically oiled walnut or other wood veneers
Grille: Removable acoustic fabric grille

The 620 cabinet was the result of extensive research by Altec engineers to create the ideal enclosure for the 604 driver, providing the proper acoustic loading for both the woofer and the integrated horn.

Performance Characteristics

Owners and audio professionals praise the Model 17 for:

Exceptional Coherence: Single-point source provides perfect integration
Natural Midrange: The 604 driver is renowned for its lifelike midrange reproduction
Good Bass Extension: 620 cabinet provides solid bass into the 30s Hz
High Sensitivity: 98-100 dB efficiency works well with low-powered amplifiers
Wide Dispersion: Coaxial design provides consistent off-axis response
Dynamic Capability: Can handle complex musical passages with ease

Studio Monitor Heritage

The 604 duplex driver has a long history in professional audio:

Broadcast Monitoring: Used by radio and television stations worldwide
Recording Studios: Found in many famous recording studios
Mastering Facilities: Valued for their accuracy and translation
Film Production: Used in film mixing and post-production

The Model 17 brought this professional monitoring capability into the home, offering studio-grade performance in a domestic-friendly package.

Amplifier Pairing

With high sensitivity and 8Ω impedance, the Model 17 works well with:

Tube Amplifiers: Particularly single-ended triode (SET) designs
Vintage Solid-State: Classic receivers from the 1970s
Modern Amplifiers: Both solid-state and tube designs
Low-Powered Amps: 5-20 watts is often sufficient for normal listening

The coherent presentation makes the Model 17 particularly revealing of amplifier character, making them excellent for evaluating different amplification options.

Comparison with Other Altec Models

Model	Configuration	Driver	Characteristics
Model 17	2-way coaxial	604-8G	Coherent, natural, excellent imaging
Model 19	2-way separate	416 + 802/811B	Dynamic, impactful, classic Altec sound
Model 14	3-way	15" + mid + horn	Full-range, extended bass
VOTT A7	2-way horn	416 + 802/811B	Professional, high-output, cinema sound

Restoration and Maintenance

Common restoration tasks for Model 17 speakers:

Crossover Recap: Replacing aging electrolytic capacitors with modern film capacitors
Driver Inspection: Checking 604 drivers for proper operation
Cabinet Refinishing: Restoring wood veneers if damaged
Grille Replacement: Installing new acoustic fabric if original is damaged
Internal Damping: Adding or replacing internal damping material

The 604-8G drivers are generally robust, but may need diaphragm replacement or remagnetizing if heavily used.

Historical Context

The Model 17 represents Altec's commitment to bringing professional monitoring technology to the home market. During the 1970s, as high-fidelity audio became more popular, audiophiles sought speakers that could deliver studio-quality sound in domestic environments. The Model 17 answered this demand by packaging the legendary 604 duplex driver—already proven in professional applications—in a home-friendly cabinet.

Pricing when new was substantial, reflecting the quality of components and construction. Today, well-preserved examples command premium prices on the vintage market.

Legacy

The Model 17 has achieved legendary status among vintage audio enthusiasts:

Collector Favorite: Highly sought after and commanding premium prices
Reference Standard: Many consider them a benchmark for natural sound
Enduring Performance: Still competitive with modern high-end speakers
Investment Value: Prices have appreciated significantly over time

Well-maintained Model 17 speakers typically sell for $4,000-$6,000 per pair, with exceptional examples commanding even higher prices. They are often described as "forever speakers" that satisfy so completely that upgrading becomes unnecessary.