The Marantz PMD670 is a professional portable solid-state recorder featuring compact flash recording, built-in stereo microphones, XLR inputs with phantom power, USB connectivity, balanced analog inputs/outputs, digital I/O, and operates on both AC power and batteries. Below are key sections for technical specifications, disassembly procedures, circuit diagrams, troubleshooting, and maintenance.
Key technical parameters and performance characteristics of the Marantz PMD670.
| Parameter | Specification |
|---|---|
| Recording Media | CompactFlash Card (Type I/II) |
| Recording Format | WAV (16/24-bit), MP3 |
| Sample Rates | 44.1kHz, 48kHz, 96kHz |
| Inputs | 2 XLR/TRS combo, stereo mini-jack |
| Outputs | XLR balanced, stereo mini-jack, headphone |
| Phantom Power | +48V |
| Frequency Response | 20Hz - 20kHz ±1dB |
| Signal-to-Noise Ratio | >90dB |
| Power Supply | 12V DC, 8 AA batteries |
| Dimensions | 240 x 160 x 65 mm |
| Weight | 1.2 kg (with batteries) |
Step-by-step instructions for safely disassembling the PMD670 unit.
WARNING! Use proper ESD protection. Handle flex cables with care to avoid damage.
Complete schematic diagrams for all major circuit sections.
System-level block diagrams showing signal flow and interconnections.
Audio Signal Path: Input → Preamp → ADC → DSP → Memory → DAC → Output
Power Distribution: DC Input → Voltage Regulators → Various Circuit Blocks
Control System: Front Panel → Microcontroller → Display → Memory → Audio Processing
Printed circuit board layouts with component placement and routing.
Note: All measurements in millimeters. Reference designators match parts list.
Detailed component identification and location on PCBs.
| Reference | Component | Location |
|---|---|---|
| U1 | Main DSP Processor | Main PCB, center |
| U2 | Flash Memory Controller | Main PCB, near CF slot |
| Q1-Q4 | Power MOSFETs | Power supply section |
| IC1-IC2 | Op-amps | Analog input section |
| X1 | Crystal Oscillator | Near DSP |
| F1 | Main Fuse | DC input jack |
Common issues and diagnostic procedures.
| Symptom | Possible Cause | Corrective Action |
|---|---|---|
| No power | Dead batteries, faulty DC jack | Check batteries, test DC input, verify fuse F1 |
| No audio recording | Input settings, faulty preamps | Check input source, test preamp ICs |
| Card not recognized | Dirty contacts, faulty card | Clean CF contacts, try different card |
| Distorted audio | Clipped input, faulty ADC | Reduce input level, check ADC reference |
| Display issues | Ribbon cable, backlight | Reseat display cable, check backlight inverter |
Factory calibration and alignment procedures.
CAUTION! Use calibrated test equipment. Follow ESD precautions.
Routine maintenance and cleaning procedures.
Clean exterior with soft, dry cloth. Clean connectors with contact cleaner. Lubricate mechanical parts as needed. Check battery contacts for corrosion.
WARNING! Do not use solvents on plastic surfaces. Unplug power before cleaning.
Complete list of replacement parts and components.
| Part Number | Description | Qty |
|---|---|---|
| PMD670-MAIN | Main PCB Assembly | 1 |
| PMD670-FRONT | Front Panel Assembly | 1 |
| PMD670-CASE | Main Enclosure | 1 |
| PMD670-PWR | Power Supply Board | 1 |
| PMD670-LCD | LCD Display Module | 1 |
| PMD670-KNOB | Control Knob | 4 |
Important safety precautions for service personnel.
Always disconnect power before servicing. Use proper ESD protection. Follow local electrical safety regulations. Replace safety-critical components only with specified parts. High voltages present in power supply section.
Service Contact: Authorized Marantz service centers only.
Support: www.marantz.com