Mcintosh MR85 AM/FM Tuner

General:
An excellent modern tuner from McIntosh that perfectly matches your other Mc gear, whether new or vintage.  A great value considering the new model will set you back $5500.

Superb sensitivity and noise rejection for bringing in even the most distant stations. 

Will require a good quality antenna for optimum performance, or just a simple whip antenna to do a good job bringing in your nearby stations. We strongly recommend the Magnum Dynallab ST2 Omnidirectional FM antenna which will also work inside if you can't mount outside. This is the "only" antenna our staff uses.

This tuner includes original manual and the high quality McIntosh branded AM antenna pictured as well.

Cosmetic Notes:
The glass faceplate and lamps were replaced in December of 2023. The new glass has slightly different light diffusion so the green lettering may appear slightly different than pieces from the same production year.

Light marks and scratches are visible on the metal trim pieces that surround the glass faceplate.

Technical Notes:
This tuner is able to accept a second AM/FM tuner module which allows two broadcasts to be received simultaneously. This feature is most commonly used in distributed audio systems. This specific tuner only has (1) tuner module installed.

Brand Background:
McIntosh Laboratory is an American manufacturer of handcrafted high-end audio equipment based in Binghamton, New York. The company was founded in 1949 by Frank McIntosh. The company designs and produces audio amplifiers, stereo tuners and other consumer electronics products.

Ownership:
Single Owner

Connections:
RCA outputs, IEC Power Cord.

Cosmetic Condition:
7/10 = Good. One or two minor scratches. Well Maintained.. See our detailed rating description here.

Working Condition:
Working perfectly and tested in our lab.

Included:
Exactly as pictured and described above.

Packing:
Original Manufacturers Packing

Specs:
FM Tuner Specifications
Useable Sensitivity
14dBF which is 1.4uV across 75 ohms

50dB Quieting Sensitivity
Mono: 19dBF which is 2.4uV across 75ohms 
Stereo: 35dBF which is 15uV across 75 ohms

Signal To Noise Ratio
Mono: 75dB 
Stereo: 70dB

Frequency Response
Mono: +0,-1dB from 20 to 15,000Hz 
Stereo: +0,-1dB from 20 to 15,000Hz

Harmonic Distortion
Mono: 
0.3% at 100Hz 
0.3% at 1,000Hz
0.3% at 10,000Hz

Stereo: 
0.45% at 100Hz 
0.45% at 1,000Hz
0.65% at 10,000Hz

Intermodulation Distortion
Mono 0.25% 
Stereo 0.45%

Capture Ratio
1.2dB

Alternate Channel Selectivity
75dB

Spurious Response
100dB

Image Response
75dB

RF Intermodulation
65dB

Stereo Separation
45dB at 100Hz 
45dB at 1,000Hz 
35dB at 10,000Hz

SCA Rejection
65dB

AM Tuner Specifications
Sensitivity
20uV External Antenna Input

Signal To Noise Ratio
48dB at 30% modulation
58dB at 100% modulation

Harmonic Distortion
0.5% maximum at 50% modulation

Frequency Response
50Hz to 6kHz NRSC

Adjacent Channel Selectivity
45dB minimum IHF

Image Rejection
65dB minimum from 540 to 1600kHz

IF Rejection
80dB minimum
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Link to Manual:
Click Here

Recommended Cables:

Kimber Kable - RCA Interconnects - Better

Kimber Kable - RCA Interconnects - Best 

Kimber Kable - Power Cords - Better

Kimber Kable - Power Cords - Best

Testing Process:

We start with a visual inspection of all internal components to make sure that there are no signs of heat stress or damage. Capacitors are checked for telltale signs of predictive failure including bulging, shrunken wrappers, or physical leakage. We also inspect the PCBs for discoloration from resistors or transistors that may have been running hot. On vintage units we often spot check select capacitors for value and ESR. Vintage analog tuners also have moving parts related to the tuning gang and dial string. These parts are inspected for smooth operation.

If the unit passes visual inspection it is bench tested for a handful of key performance parameters using a Sencore SG80 AM/FM Stereo Analyzer. The SG80 allows us to “simulate” an ideal radio station using precision test signals instead of music. This device, in conjunction with an oscilloscope allows us to properly evaluate the following parameters:

1.  AM Reception (Where Applicable)

2.  FM Mono Reception & Tuning Meter Function

3.  FM MPX Reception (Stereo)

4.  Dial Tracking - How accurately the tuner dial or display indicates the actual frequency of the broadcast being received.

5.  Stereo Separation - A properly working stereo tuner will have minimal crosstalk between the left and right channel.

6.  Sensitivity & Signal Strength Meter Function - By lowering the output of the SG80 we can simulate weak stations and determine how well the tuner will be able to pull in weak distant stations. This adjustment also helps us verify signal strength meter function.

If the tuner has acceptable performance related to the parameters above we connect the unit for listening tests with a simple dipole antenna. We listen for audio reproduction quality of local stations and evaluate how many stations the tuner can receive while we sweep through the dial. We are looking to verify that the tuner can decode stereo on strong local broadcasts and pick up a wide variety of local stations at the bottom, middle, and top of the frequency band. At this point we also test convenience features such as muting, filters, built in oscilloscope function, etc.

We finish up with an extended listening test on our long term test rig. We tune in a strong local station and monitor for drift over a 2-3 hour period.