The AKG SolidTube
cardioid condenser microphone
The AKG Model SolidTube is a large diaphragm condenser microphone that benefits from the combination of modern solid-state technology and vacuum tube-driven circuitry. The microphone, released in 1997, AKG’s Jubilee year, provides the characteristic warmth and generous margin of overload expected from classic tube-powered designs. Solid-state electronics within the N-Solid power supply ensure quiet and reliable operation.
The SolidTube has a large double-screened housing that reacts minimally with the capsule and provides shielding from RF interference. Frequency response remains relatively flat within the range of ±2 dB. The mid-range cut at approximately 2 kHz and presence rise above 10 kHz are signature characteristics of AKG large diaphragm condenser mics dating back to the classic C 12. They provide depth and clarity to any recording. Mid-band pattern rejection at 180° is in excess of 20 dB.
The microphone is response-tailored for solo vocal and instrumental pickup in the studio, and as such has only a dedicated cardioid pattern. The SolidTube is shipped with all necessary cabling, an isolation shock mount, windscreen, and a custom aluminum flight case.
Text copied from the AKG SolidTube specification sheet.
I had assumed this was the vacuum tube’s filament glowing inside the mic…
…but friend Torben Lysholm emailed me from Denmark and set me straight:
“It’s an orange LED placed in the middle of the tube socket that lights up.”
Low-frequency noise below 100 Hz can be eliminated by turning the low-cut switch located on the front panel of the unit’s external power supply. There is also a ground lift switch next to the audio output connector on the power supply that can isolate the signal ground from the chassis ground, quickly eliminating hum.
Disassembled view of this mic.