Description
Rackmount mic preamp from Altec. The 1689A has two inputs with direct outputs and a transformer-coupled mixed output with EQ controls
The unit is more complex & capable than it looks at first. The internal switches set gain, phantom power & high-pass filters per channel and each mic channel has an unbalanced direct output which is after the front-panel gain control. There’s a low-pass filter and eq defeat switch for the main output and the two Links jacks allow connection of additional mixer / preamplifiers
Clearly designed to be configured & then racked for use, the 1689A needs a bit of thought before use but has lots of useful options
The 1689A front panel has:
- Front-panel gain control for mixed output
- Main output mix controls for Ch 1 & 2
- Main output low & high-frequency shelving EQ controls
Internally, the 1689A has:
- Transformers for Ch 1 & 2
- Mic / line switches for Ch 1 & 2
- Gain select switches for Ch 1 & 2
- 250 Hz high-pass switches for Ch 1 & 2
- Phantom power switches for Ch 1 & 2
- Low-pass 5 kHz filter switch for main output
- EQ bypass switch
These Altec units are built super-tough in a steel chassis. Main inputs & output are on XLR with direct outputs & links on jack sockets
Tested & working 100%. Photos show one of the units for sale. This unit has a bent shaft for the Master output pot but works perfectly
The service / setup manual is available under the Links tab
