Akai AM-U7
Integrated stereo amplifier from the early 1980s with a discrete open-loop design and an MC phono input.
Overview
The Akai AM-U7 is a stereo integrated amplifier from the early 1980s, and one of Akai's most popular products. The circuit is discrete-component and open-loop. Power supply stability comes from a toroidal transformer and two 15,000µF 63V capacitors. It puts out 80W per channel into 8 ohms (20Hz - 20kHz, 0.5% THD) and 100W into 4 ohms (0.7% THD). Music power is rated at 190W total. It has a moving coil (MC) phono input and a 'line straight' mode that bypasses the tone controls for a direct signal path.
Specifications
| Power Output (RMS) | 80W per channel into 8 ohms (20Hz–20kHz, 0.5% THD) |
| Power Output (1kHz) | 90W per channel into 8 ohms (0.5% THD) |
| Power Output (Dynamic) | 100W per channel into 4 ohms (0.7% THD) |
| Music Power | 190W total |
| Circuit Type | Open loop, discrete components |
| Feedback System | Non-NF circuit, Zero Drive, Dual Pole DC servo |
| Transformer | Toroidal |
| Capacitors | Two 15,000µF 63V |
| Phono Input | Moving coil (MC) |
| Feature | Line straight mode (tone control bypass) |
Design
The AM-U7 runs an open-loop circuit with discrete components and no overall negative feedback (Non-NF). Zero Drive and Dual Pole DC servo technology keep the DC offset stable. The interior is noted for quality construction and component layout. The front panel is a plastic faceplate, in line with Akai's early 1980s "space age" styling.
Market
Listings from 2021 to 2026 show functional units selling for around CA$190, with parts or repair units priced up to $199. Manuals and schematics usually sell separately for $12 - $25. The amplifier has seen more market activity and discussion in European countries like Germany and France than in North America.
eBay Listings
As an eBay Partner, we earn from qualifying purchases. This helps support our independent vintage technology research.
Related Models
- Akai AM-2400 (1978)
- Akai AM-2600 (1977)
- Akai AM-2650 (1975)
- Akai AM-2850 (1975)
- Akai AM-32 (1978)
- Eico 3150 (1967)
- Fisher CUSTOM-ELECTRA-I (K-14/K-15) (1957)
- Fisher CUSTOM-ELECTRA IV (E33/E44) (1960)
- Akai AM-73 (1973)
- Heathkit AA-32 (1960s)