Speakers (Acoustic system) 10AC-9 were produced by the Riga Radio Plant named after A.S. Popov. It was produced since 1978. The release was timed to coincide with the 1980 Olympics, so there is a nameplate “Moscow 80” on the front panel. Later, the speakers were called 10AC-209, 10AC-408 and 10AC-409.
Technical specifications.
Acoustic design – two-way system with a phase inverter.
Frequency response range: 63 – 18000Hz
Sensitivity: 85 dB
Resistance: 4 Ohm
Nominal power: 10 W
Maximum power: 25 W
Loudspeakers used: LF/MF: 25 GDN-1-4 (10 GD-34), HF: 6 GDV-1-16 (3 GD-2)
Dimensions: 360x210x177 mm
Weight: 5 kg
There are 2 speakers inside. LF+MF: 25 GDN-1-4 (10 GD-34) and HF: 6 GDV-1-16 (3 GD-2). The high-frequency filter is the simplest – it consists of 1 capacitor. The high-frequency speaker is connected through it. And the low-midrange is connected directly.
10AC-9 (from personal archive)
The appearance is of course a little shabby. But for things of this age it is normal. Especially since the storage conditions are not at all hothouse.
I wanted to make karaoke at my dacha using these speakers. I bought a microphone, an amplifier – all of this was quite inexpensive. But of course, there weren’t enough low frequencies. And normal karaoke was possible only after purchasing a subwoofer.