Tape Recording Electronics

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The Inovonics 375 is a compact, up-to-date magnetic recording electronics package, completely self-contained with integral power supply.

Available in several versions, the 375 is equally well suited to new installations, or to improve the performance and reliability of older professional tape recorders.


  • Use of electronic signal switching in monitor mode and for equalization selection, eliminating contact noise.

  • Automatic transfer of monitor to INPUT when entering the RECORD mode from SYNC.

  • Three speed equalization with wide adjustment range, accomodating both NAB and IEC characteristics at any speed from 3-3/4 to 30ips.

  • The Record Amplifier incorporates a "linearizer" circuit which may be user-adjusted to significantly reduce tape-generated odd-order harmonic distortion.

  • Two separate preamplifiers handle the normal reproduce and the SYNC reproduce functions



Frequency Response (in Hz ±2dB)

  • 30ips OVERALL/60 - 22k/ SYNC/60 - 20k

  • 15ips OVERALL/30 - 22k/ SYNC/40 - 16k

  • 7.5ips OVERALL/20 - 16k/ SYNC/30 - 8k

Signal-to-Noise Ratio (in dB)

  • 30ips/OVERALL (u’wtd -71/ wtd -78)SYNC (u’wtd -71/ wtd -80) STANDBY(u’wtd -80/ wtd -87)

  • 15ips/OVERALL (u’wtd -67/ wtd -76)SYNC (u’wtd -67/ wtd -77) STANDBY(u’wtd -74/ wtd -85)

  • 7.5ips/OVERALL (u’wtd -68/ wtd -77)SYNC (u’wtd -68/ wtd -79) STANDBY(u’wtd -74/ wtd -85)


With 250kHz erase/bias frequency, more than 75dB erasure of 500Hz signal recorded 12dB above 320nW/m Operating level.

Recorded Distortion (THD of 1kHz signal)

  • At Operating Level: LIN out/0.50% LIN in/0.15%

  • 3dB Operating Level: LIN out/1.00% LIN in/0.30%

  • 6dB Operating Level: LIN out/2.50% LIN in/0.80%

Amplifier Distortion (THD)

  • Record: 0.1% at Operating Level / 0.05% at 25dB above Operating Level

  • Repro: 0.1% at Operating Level (Clipping Level +25dBm)


  • Sensitivity: -20 to +8dBm

  • Impedance: 10K, unbalanced


  • Level: Adjustable for +4 or +8dBm from Operating Level recording; Clipping Level +25dBm

  • Impedance: Unbalanced from low impedance “voltage source” output stage. Can drive 1:1 transformer for isolation if required.

Power Requirement

±20VDC (bipolar) regulated, at 200mA per channel (including indicators) plus 250kHz sine wave at 1V r.m.s. Power Supply requirement can be met with Inovonics A/N 129403 printed-circuit assembly when combined with power transformer, bridge rectifier and filter capacitors adequate for the current required.

Size and Weight

3-1/2” x 19” x 7”; 121bs.