📍 Los Angeles County & SoCal
🔧 30+ Years Experience
🎵 McIntosh Specialist
🏢 Tek Media Group
📋 TECHNICAL DISCLAIMER: The information provided is based on my 30+ years of experience restoring McIntosh MAC 1700 receivers. This equipment contains voltages that can be dangerous. FM alignment requires specialized test equipment. I strongly recommend that only qualified technicians perform internal service. Proceed at your own risk.
⚠️ IMPORTANT – FROM MY SERVICE BENCH: The McIntosh MAC 1700 is a transitional design combining early solid-state amplifier sections with a sensitive FM tuner. Many units suffer from failed electrolytic capacitors that can damage output transistors if left unattended. I have the proper equipment and expertise to restore these classic receivers to original specifications.
About the McIntosh MAC 1700 & My Service
The McIntosh MAC 1700 is a landmark hybrid receiver from the late 1960s, representing McIntosh's transition from tube to solid-state technology. Produced from 1967 to 1970, this receiver combines a sensitive FET front-end FM tuner with a 40-watt-per-channel solid-state amplifier. The MAC 1700 features McIntosh's legendary Autoformer output transformers, delivering stable power into 4, 8, or 16 ohm loads. With its classic glass front panel, brass chassis, and unmistakable McIntosh styling, the MAC 1700 is a favorite among collectors and audiophiles who want vintage McIntosh sound with solid-state reliability.
I'm the owner and lead technician at Tek Media Group, and I've been restoring McIntosh solid-state equipment since 1994. I have extensive experience with the MAC 1700 and understand its unique architecture, including the FET front end, the early silicon transistor amplifier section, and the precision FM tuner. Every receiver that comes to my bench receives meticulous attention to preserve its legendary performance and value.
✅ WHY TRUST TEK MEDIA GROUP WITH YOUR MAC 1700:
- 30+ Years of McIntosh Solid-State Experience
- Specialized Knowledge of MAC 1700 Hybrid Architecture
- Complete FM Alignment with Professional Test Equipment
- Power Amplifier Restoration & Bias Adjustment
- FET Front End & Preamplifier Restoration
- Every Receiver Gets My Personal Attention – No Assembly Line
- Full Power Supply Rebuild & Capacitor Replacement
- Output Transistor Testing & Matching
- 90-Day Warranty on All Work
- Local Service Throughout Southern California
Restoration Services I Offer
🔧 Diagnostic & Evaluation Complete assessment with detailed report, sensitivity measurement, power output test
⚡ Power Supply Restoration Full recap of electrolytic capacitors, rectifier replacement, voltage verification
🎛️ Full Capacitor Replacement Replace all aged electrolytic, tantalum, and ceramic capacitors with high-quality modern equivalents
🔋 Transistor Testing & Replacement Test all transistors, replace failed or noisy units with modern equivalents
📻 FM Alignment Full FM alignment with professional test equipment (RF, Oscillator, IF, Detector)
🎚️ Preamplifier Restoration FET testing and replacement, capacitor replacement, level calibration
🔊 Power Amplifier Restoration Bias adjustment, capacitor replacement, output transistor verification
🏆 COMPLETE FULL RESTORATION All services above – your receiver will perform to or exceed original specifications
💡 COMPLETE RESTORATION INCLUDES: Full power supply recap • All electrolytic and tantalum capacitors • Transistor testing and replacement • Full FM alignment • Preamplifier restoration • Power amplifier rebuild • Bias adjustment • Clean controls • Sensitivity verification • Power output measurement • 90-day warranty
The McIntosh MAC 1700 – Solid-State Pioneer
🎵 McINTOSH MAC 1700 KEY FEATURES:
- Power Output: 40 watts per channel (solid-state)
- Autoformer Outputs: McIntosh's legendary output transformers for stable 4/8/16 ohm operation
- FM Tuner: Sensitive FET front-end FM section with automatic stereo switching
- FET Front End: Field-effect transistors in RF section for low noise and high sensitivity
- Solid-State Amplifier: Early silicon transistor design with complementary symmetry
- Glass Front Panel: Classic McIntosh aesthetic with backlit glass
- Built-in Stereo Multiplex: FM stereo decoder with automatic switching
- High Filter: 7kHz high-cut filter for noisy FM reception
⚠️ IMPORTANT – MAC 1700 SPECIFIC CONSIDERATIONS: The MAC 1700 uses electrolytic and tantalum capacitors that are known to fail with age. Failed capacitors can cause noise, hum, and can damage output transistors. I replace all aged capacitors. The early silicon transistors can develop noise over time – I test and replace as needed. The FM tuner section uses FETs that can fail – I have replacements available.
Detailed Repair Information – From My Workbench
⚡ POWER SUPPLY (Critical for Performance)
- Main Filter Capacitors: Large electrolytic caps – I replace with 105°C rated, high-ripple current types
- Regulator Capacitors: I replace all small electrolytic and tantalum capacitors in the power supply
- Bridge Rectifier: I test and replace if necessary
- Voltage Verification: I verify proper supply voltages (±15V, +40V, etc.) after restoration
- Ripple Measurement: I verify power supply ripple below 10mV for low noise floor
📻 FM TUNER SECTION (FET Front End)
PRECISION FM ALIGNMENT:
- Front End: I clean and lubricate the tuning capacitor, verify no bent plates
- FET RF Amplifier: I test and replace weak FETs – critical for sensitivity
- Local Oscillator: I verify oscillator operation and tracking across the dial
- Mixer Stage: I test and align for optimal image rejection
- IF Amplifiers: I align IF transformers for proper bandwidth and gain
- FM Detector: I test and align discriminator or ratio detector
- IF Alignment Procedure: I use sweep generator and oscilloscope for proper IF response
🎚️ PREAMPLIFIER & CONTROL SECTION
PREAMP RESTORATION:
- FETs in Preamp: I test all FETs and replace noisy units
- Coupling Capacitors: I replace with high-quality film capacitors for best sound
- Level Controls: I clean and lubricate volume, balance, and tone controls
- Input Switching: I clean all input selector switches
- Phono Preamplifier: I restore the phono section for proper RIAA equalization
- Tone Control Circuitry: I verify and calibrate bass and treble response
🔊 SOLID-STATE POWER AMPLIFIER SECTION
POWER AMP RESTORATION:
- Output Transistors: I test all output transistors, replace failed or mismatched units
- Driver Transistors: I test and replace noisy or failed driver transistors
- Output Transformers: I verify McIntosh Autoformer output transformers
- Coupling Capacitors: I replace with high-quality film capacitors for stability
- Bias Adjustment: I set bias for optimal output transistor operation
- Emitter Resistors: I verify and replace drifted resistors
- Power Output Verification: I test power output into 4, 8, and 16 ohm loads
- Distortion Measurement: I verify THD below 0.5% at rated power
🎛️ MULTIPLEX DECODER (FM Stereo)
- Multiplex Board Recap: I replace all capacitors on the multiplex decoder board
- 19kHz Pilot Filter: I align the pilot filter for proper stereo triggering
- 38kHz Subcarrier Oscillator: I calibrate the oscillator for optimal stereo separation
- Stereo Separation Adjustment: I adjust for maximum separation (>30dB typical)
- Stereo Beacon Circuit: I verify the stereo indicator lamp circuit
📡 TUNING INDICATOR
- Center Tuning Meter: I calibrate the tuning meter for accurate center-of-channel indication
- Signal Strength Meter: I verify meter response for accurate signal strength indication
- Meter Illumination: I replace burned-out lamps with correct voltage bulbs or LED upgrades
Common McIntosh MAC 1700 Problems I Solve
#1 Electrolytic Capacitor Failure
Symptom: Excessive hum, low output power, unstable operation, noise.
My Solution: I replace all electrolytic capacitors in the power supply and signal paths.
#2 Tantalum Capacitor Failure
Symptom: Short circuits, noise, distortion, intermittent operation.
My Solution: I replace all tantalum capacitors with high-quality modern electrolytics or film caps.
#3 Weak Sensitivity / Poor FM Reception
Symptom: Only strong stations come in, weak stations are noisy or absent.
My Solution: I perform full FM alignment, test and replace weak FETs, verify front end components.
#4 No Stereo or Poor Stereo Separation
Symptom: Stereo light doesn't come on, stereo sound is mono or distorted.
My Solution: I align the multiplex decoder, replace aged capacitors, verify stereo beacon circuit.
#5 Distorted or Weak Sound
Symptom: Low output power, distortion, one channel weak or dead.
My Solution: I test output transistors, bias power amplifier, replace coupling capacitors, verify Autoformers.
#6 Drifted Resistors
Symptom: Off-spec voltages, poor performance, instability.
My Solution: I test all carbon comp resistors and replace any drifted more than 10% from nominal.
#7 Noisy Controls / Intermittent Operation
Symptom: Crackling when adjusting volume or tone controls, dropouts.
My Solution: I clean all controls and switches with DeOxit, lubricate tuning capacitor bearings.
#8 Noisy Transistors
Symptom: Hiss, crackling, intermittent noise, especially in preamp section.
My Solution: I test all transistors and replace noisy units with modern equivalents.
#9 Meter Not Working
Symptom: Tuning meter or signal strength meter doesn't move.
My Solution: I test meter movement, verify meter drive circuit, replace failed components.
My Restoration Process
✅ Step 1: Consultation & Diagnostic – I discuss your receiver's condition and goals
✅ Step 2: Initial Testing – I power up safely on variac, measure voltages, document baseline performance
✅ Step 3: Power Supply Restoration – Replace ALL electrolytic and tantalum caps, verify voltages
✅ Step 4: Capacitor Replacement – Replace all paper and ceramic capacitors throughout the receiver
✅ Step 5: Resistor Testing & Replacement – Test all carbon comp resistors, replace drifted units
✅ Step 6: Transistor Testing – Test all transistors on semiconductor tester, replace noisy or failed units
✅ Step 7: Preamplifier Restoration – Test and replace FETs, recap preamp board
✅ Step 8: Clean & Lubricate – Tuning capacitor, controls, switches, connectors
✅ Step 9: FM Alignment – Full FM alignment with sweep generator and oscilloscope
✅ Step 10: Multiplex Decoder Alignment – Calibrate for optimal stereo separation (>30dB)
✅ Step 11: Power Amplifier Restoration – Bias output transistors, test power output
✅ Step 12: Performance Verification – Sensitivity, stereo separation, power output, distortion measurement
✅ Step 13: Burn-in & Final Testing – 24-hour burn-in, final verification, service report
📋 TIMELINE: Full restoration: 3-4 weeks. Partial: 1-2 weeks. Rush service available – just ask.
Capacitor Replacement Database
⚠️ Total: 80-100 capacitors – I replace ALL aged caps
POWER SUPPLY CAPACITORS
| Designator | Original | My Replacement | Notes |
| C1, C2 | 4700µF/40V | 4700-6800µF/63V, Snap-in, 105°C | Main filter caps – critical for hum reduction |
| C3, C4 | 1000µF/25V | 1000µF/35V, Low ESR | Secondary filtering |
| C5-C12 | 100-470µF/16-25V | Same / higher voltage, 105°C | Regulator and decoupling |
| Tantalum Caps | Various | Modern electrolytic or film | Replace ALL tantalum capacitors |
COUPLING & SIGNAL CAPACITORS
| Position | Original | My Replacement | Notes |
| Power Amp Coupling | 0.1µF / 200V (film) | Polypropylene film, 250V+ | Critical for stability |
| Preamp Coupling | 0.047µF / 100V | Polypropylene film | Signal path – affects sound quality |
| Phono EQ | 0.001-0.1µF | Polystyrene or polypropylene | Critical for RIAA accuracy |
| Multiplex Board | Various values | Polystyrene or polypropylene | Critical for stereo separation |
TUNER SECTION CAPACITORS
| Position | Original | My Replacement | Notes |
| IF Transformers | Ceramic caps | Silver mica | Critical for IF alignment stability |
| Discriminator | Ceramic caps | Silver mica or film | Affects FM detection |
| Front End | Ceramic caps | Silver mica or NP0/C0G | Critical for oscillator stability |
Transistor Complement & Recommendations
| Position | Original Type | Quantity | My Replacement |
| Output Transistors | 2N3055 / MJ15003 | 4 | MJ15003 or MJ15024 (upgraded) |
| Driver Transistors | 2N4241 / 2N4240 | 4 | MJ15030/MJ15031 or equivalent |
| FETs (RF) | 2N3823 / MPF102 | 2 | Modern N-channel JFET equivalent |
| FETs (Preamp) | 2N3819 | 2 | Modern N-channel JFET equivalent |
| Small Signal | 2N3391, 2N3392 | Various | 2N3904/2N3906 or equivalent |
I test all transistors on a semiconductor tester and replace noisy or failed units with modern equivalents. I can also upgrade output transistors to higher-spec modern types for improved reliability.
Performance Specifications (After Restoration)
| Parameter | Original Spec | My Target After Restoration |
| Power Output (per channel) | 40W RMS | 40W+ into 4/8/16 ohms |
| Frequency Response | 20Hz-20kHz ±0.5dB | 20Hz-20kHz ±0.5dB |
| Total Harmonic Distortion | <0.5% at rated power | <0.3% at rated power |
| FM Sensitivity (IHF) | 2.5µV | 2.0µV or better |
| Stereo Separation | >30dB at 1kHz | >35dB at 1kHz |
| Hum & Noise | -80dB | -85dB or better |
I verify all specifications on precision test equipment and provide a detailed service report with before/after measurements for every restoration.
Frequently Asked Questions
❓ What makes the MAC 1700 different from the MAC 1500?
The MAC 1500 is a tube/FET hybrid with a tube power amplifier. The MAC 1700 is a solid-state/FET hybrid with a solid-state power amplifier. Both share similar tuner sections, but the MAC 1700 represents McIntosh's transition to solid-state amplification.
❓ How long does a full restoration take?
Full restoration: 3-4 weeks due to the complexity of the solid-state amplifier and FM alignment. Partial restoration: 1-2 weeks. Rush service available – just call me.
❓ Do you offer pickup and delivery?
Yes, for Los Angeles, Orange County, Ventura, Riverside, San Bernardino, and surrounding areas. You're also welcome to drop off at my LA County shop.
❓ Can you replace the FETs in the tuner and preamp sections?
Yes. The FETs in the tuner and preamp sections can fail over time. I test all FETs and replace failed or noisy units with modern equivalents that maintain the original performance.
❓ What output transistors do you recommend for the MAC 1700?
I recommend upgraded MJ15003 or MJ15024 output transistors for improved reliability and performance. These are modern equivalents that exceed the original specifications.
❓ Do you have spare parts for the MAC 1700?
Yes, I have accumulated a stock of critical spare parts over 30 years, including Autoformers, tuning capacitors, FETs, transistors, and mechanical parts for McIntosh receivers.
❓ Do you warranty your work?
Yes, I offer a 90-day warranty on all parts and labor. I stand behind every restoration I complete.
McIntosh MAC 1700 Technical Specifications
| Parameter | Specification |
| Manufacturer | McIntosh Laboratory, Inc. |
| Model | MAC 1700 |
| Production Years | 1967-1970 |
| Power Output | 40 watts per channel (solid-state) |
| Frequency Response | 20Hz-20kHz ±0.5dB |
| Total Harmonic Distortion | <0.5% at rated power |
| FM Sensitivity (IHF) | 2.5µV |
| FM Stereo Separation | >30dB at 1kHz |
| Inputs | Phono, Tuner, Aux, Tape Head, Tape Monitor |
| Outputs | 4, 8, 16 ohm speaker, Tape Out, Headphone |
| Output Transformer | McIntosh Autoformer |
| Weight | Approximately 32 lbs (14.5 kg) |
My Service Area – Southern California
I serve Los Angeles County, Orange County, Ventura County, Riverside County, San Bernardino County, and surrounding areas. Local pickup and delivery available.
Los Angeles County:
LA Burbank Glendale
Santa Monica Hollywood Pasadena
Orange County:
Santa Ana Anaheim Irvine
Huntington Beach Costa Mesa
Ventura County:
Ventura Oxnard Thousand Oaks
Riverside & San Bernardino:
Riverside Ontario Rancho Cucamonga
San Bernardino Redlands
Tek Media Group — Professional Audio Restoration Since 1994
📞 (818) 244-4440 | ✉️ service@tekmediagroup.com
Serving Los Angeles, Orange County, Ventura, Riverside, San Bernardino, and all of Southern California
Specializing in McIntosh, Marantz, Scott, Fisher, and vintage audio restoration
McIntosh MAC 1700 Specialist • Solid-State/FET Hybrid Expert
