FM 133 Linearizer vs Accuphase DF-75
The DF-75's thd is 0.001% against the FM 133 Linearizer's 0.010%, its height 151 mm against 62 mm, its depth 396 mm against 290 mm, and its width 465 mm against 245 mm.
AI-generated product photo — not official manufacturer imagery.
FM 133 Linearizer
FM Acoustics LTDDigitalDigital Processors
Estimated price (community-sourced)
$15,715.90
Around — community and catalog average, updates slowly
About the FM 133 Linearizer
The FM Acoustics LTD FM 133 Linearizer is a high-level, single-ended harmonic/constant-phase linearizer intended for insertion in a preamplifier tape loop or between a line preamplifier and power amplifier. It uses five adjustable frequency bands centered at 50 Hz, 200 Hz, 800 Hz, 3.2 kHz, and 12.8 kHz. The circuit is designed to pass the signal transparently while permitting controlled addition or subtraction around these bands to correct tonal or recording-related problems. It includes main and tape-monitor signal paths, bypass operation, and a ground-lift arrangement. The FM 133 is the unbalanced counterpart to the balanced FM 233. Available manufacturer and distributor material confirms the model and its technical data, but does not clearly establish whether production has permanently ended; it should therefore be treated as a legacy or possibly discontinued model rather than definitively declared discontinued.
Specifications
Analog Output
Analog signal output specifications
- THD
- 0.010%
Connectivity
Input and output connections
- Analog Inputs
- RCA
- Analog Outputs
- RCA
Physical Dimensions
Size, weight, and appearance
- Dimensions
- 245 × 62 × 290 mm (W × H × D)
Never published
- Digital Audio — the maker never published this. Checked 15 sources on 7 Sept 2026
Specifications are community-contributed and may not be accurate or complete. Verify all details with the manufacturer before making purchasing decisions. Terms & Conditions