Mechlabor STM-610 Tape Recorder

Studio stereo reel-to-reel tape recorder, solid-state electronics. Manufacturer by Mechanikai Laboratórium (Mechlabor), Budapest, Hungary.

Mechanical & Tape Transport:

• Motors / Heads: 3 motors, 3 heads (record, playback, erase)
• Tape speeds: standard 38.1 cm/s and 19.05 cm/s; optional slower speed 9.52 cm/s in some versions
• Capstan drive: servo-controlled, directly driven; high speed stability better than 10⁻⁵ per °C, not affected by mains frequency or voltage fluctuations
• Tape slip (slippage): max 0.1%
• Tape tension (before capstan): 75 “p” ± 15 “p” (manufacturer’s unit)
• Reel size: minimum hub dia 57 mm; maximum reel diameter 270 mm (IEC reel sizes I, II, III)
• Rewind time: ~2.5 minutes for 1000 m reel

Performance / Audio Specs

• Wow & Flutter (DIN 45507): ~0.035% at 38.1 cm/s; ~0.065% at 19.05 cm/s
• Frequency response (over tape):
  • At 38.1 cm/s: approx. 30 Hz – 18,000 Hz (±3 dB)
  • At 19.05 cm/s: approx. 40 Hz – 18,000 Hz (±3 dB)
• Signal-to-Noise Ratio (20 Hz-20 kHz, with tape):
  • At 38.1 cm/s: ~67 dB (mono), ~66 dB (stereo)
  •  At 19.05 cm/s: ~65 dB (mono), ~64 dB (stereo)
• Distortion from tape:
  •  At 38.1 cm/s: ~0.4% (mono), ~0.6% (stereo)
  • At 19.05 cm/s: ~0.5% (mono), ~0.8% (stereo)
• Erase depth: ≥ 80 dB at 1 kHz
• Bias frequency: 240 kHz
• Erase frequency: 120 kHz
• Cross-talk attenuation (stereo): ≥ 42 dB at 1 kHz

Dimensions: 700 x 630 x 930 mm
Weight: 75kg