MX113 vs MR74

jlovda

Things I loved from the 60's and 70's
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One simple question. Is the tuner in an MX113 exactly the same as an MR74? In other words, if I am looking for an MR74 but a great deal on an MX113 appears, should I jump? I have no interest in another preamp.
Thanks
 
Exactly the same? No, but I had an MX113 and liked it very much--space-saver too!

The specs below are from Roger Russell's website (with links).

MX113: http://www.roger-russell.com/tunpre.htm#mx113

AM SECTION: Sensitivity 75uV, S/N 45dB, Distortion 1%, Response down 6dB at 3500Hz, Selectivity 45dB, Image rejection 65dB.

FM SECTION: Sensitivity 2.5uV, Distortion 0.7% in stereo, Response 20-15kHz (+1.0 -1.0dB), Capture ratio 1.5dB, Spurious rejection 90dB, Image rejection 95dB, Stereo separation 35dB. Selectivity: adjacent channel 15dB IHF, alternate channel 88dB IHF.

PREAMPLIFIER SECTION: Response 20-20kHz (+0.5 -0.5dB), Distortion 0.1%, Input sensitivity and impedance: aux 0.25V at 250k, phono 2.0mV at 47k. Voltage gain 20dB aux, 62dB phono. Hum and noise: aux -85dB, phono 70dB below 10mV input. Tone controls: bass +16dB to -18dB, treble +20 to-20dB. . LF filter 50Hz at 6dB/octave. HF filter 5kHz at 6dB/octave. Phase switch: 0 or 180.

FRONT PANEL: Glass front panel. Illuminated. Input selector: aux, tape, am, fm, ph 1, ph 2. Dual concentric bass and treble controls. Pushbutton switches: mono/stereo, lf, hf, tape, muting, select. Balance. Loudness: in or out. Volume with power switch. Tuning control. Illuminated dial. Tuning meter. Stereo light. Panloc buttons.

TOP PANEL: Phase switch, Panel lamp intensity, Muting control.

BACK PANEL: Inputs: aux, tape, ph 1, ph 2. Ground terminal. Outputs: main, tape, l+r. Push terminals: am ant, gnd, 300 ohm and 75 ohm antenna. Scope outputs: tp 1 and tp 2. AC outlets: 2 switched, 1 unswitched. Fuse. Panloc mounting.

Size: 5-7/16"H, 16"W and 13"D. Weight 26 lb. Sold from 1971-1980. Last retail price $1099.00

MR74: http://www.roger-russell.com/tuners.htm#mr74

FM SECTION: Sensitivity 2.5uV. Response 20-15kHz (+1 -1dB) stereo. Distortion 0.5% in stereo. Capture ratio 1.5dB. Selectivity: adjacent channel = 6dB normal, 15dB narrow. alternate channel = 68dB normal, 88dB narrow. Image rejection 95dB. S/N 70dB. Separation 35dB@1kHz. Spurious rejection 90dB. SCA rejection 50dB. Stereo filter noise reduction: 10dB position 1, 20dB position 2

AM SECTION: Sensitivity 75uV. Response: Normal -6dB at 3.5kHz, Narrow -6dB at2.1kHz. Distortion 1.0%. Adjacent channel selectivity: normal 35dB, narrow 45dB. S/N 55dB. Image rejection 65dB.

FRONT PANEL: Glass front panel. Mode selector sw: am, fm or fm mono. Stereo filter sw: out, 1 or 2. Selectivity sw: normal or narrow. FM muting sw: out, distant or local. Volume with on-off switch. Tuning ctrl. Signal strength and tuning meters. MPX indicator. Multipath indicator.

BACK PANEL: Audio out 2.5V variable and fixed. Built-in ferrite loopstick. AM ant sw: ext or loop. Ext am antenna. 300 or 75 ohm fm cable input. Scope outputs. Panloc mounting.

Size 5-7/16"H, 16"W and 13"D behind panel. Weight 25 lb. Sold from 1972-1979. Last retail price $849.00
 
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Exactly the same? No, but I had an MX113 and liked it very much--space-saver too!

The specs below are from Roger Russell's website (with links).

MX113: http://www.roger-russell.com/tunpre.htm#mx113

FM SECTION: Sensitivity 2.5uV, Distortion 0.5% in mono, Response 20-20kHz (+1.0 -1.0dB), Capture ratio 1.8dB, Spurious rejection 100dB, Image rejection 80dB,

PREAMPLIFIER SECTION: Response 20-20kHz (+0.5 -0.5dB), Distortion 0.1%, Input sensitivity and impedance: aux 0.25V at 250k, phono 2.0mV at 47k. Voltage gain 20dB aux, 62dB phono. Output: 2.5V (10V max). Hum and noise: aux -85dB, phono 70dB below 10mV input. Tone controls: bass +16dB to -20dB, treble +20 to-20dB. . LF filter 50Hz at 6dB/octave. HF filter 5kHz at 6dB/octave. Phase switch: 0 or 180.

FRONT PANEL: Glass front panel. Illuminated. Input selector: aux, tape, fm, ph 1, ph 2. Dual concentric bass and treble controls. Pushbutton switches: mono/stereo, lf, hf, tape, muting, loud. Balance. Volume with power switch. Tuning control. Illuminated dial. Electron ray tuning indicator. Stereo light. Panloc buttons.

TOP PANEL: Phase switch, Panel lamp intensity, Muting control.

BACK PANEL: Inputs: aux, tape, ph 1, ph 2. Ground terminal. Outputs: main, tape, l+r. Push terminals: gnd, 300 ohm and 75 ohm antenna. Scope outputs: tp 1 and tp 2. AC outlets: 2 switched, 1 unswitched. Fuse. Panloc mounting.

Size: 5-7/16H, 16"W and 13"D. Weight 24 lb. Sold from 1969-1971. Last retail price $549.00

MR74: http://www.roger-russell.com/tuners.htm#mr74

FM SECTION: Sensitivity 2.5uV. Response 20-15kHz (+1 -1dB) stereo. Distortion 0.5% in stereo. Capture ratio 1.5dB. Selectivity: adjacent channel = 6dB normal, 15dB narrow. alternate channel = 68dB normal, 88dB narrow. Image rejection 95dB. S/N 70dB. Separation 35dB@1kHz. Spurious rejection 90dB. SCA rejection 50dB. Stereo filter noise reduction: 10dB position 1, 20dB position 2

AM SECTION: Sensitivity 75uV. Response: Normal -6dB at 3.5kHz, Narrow -6dB at2.1kHz. Distortion 1.0%. Adjacent channel selectivity: normal 35dB, narrow 45dB. S/N 55dB. Image rejection 65dB.

FRONT PANEL: Glass front panel. Mode selector sw: am, fm or fm mono. Stereo filter sw: out, 1 or 2. Selectivity sw: normal or narrow. FM muting sw: out, distant or local. Volume with on-off switch. Tuning ctrl. Signal strength and tuning meters. MPX indicator. Multipath indicator.

BACK PANEL: Audio out 2.5V variable and fixed. Built-in ferrite loopstick. AM ant sw: ext or loop. Ext am antenna. 300 or 75 ohm fm cable input. Scope outputs. Panloc mounting.

Size 5-7/16"H, 16"W and 13"D behind panel. Weight 25 lb. Sold from 1972-1979. Last retail price $849.00
You used the MX114 tuner specs, not the MX113.

MX113:
FM SECTION: Sensitivity 2.5uV, Distortion 0.7% in stereo, Response 20-15kHz (+1.0 -1.0dB), Capture ratio 1.5dB, Spurious rejection 90dB, Image rejection 95dB, Stereo separation 35dB. Selectivity: adjacent channel 15dB IHF, alternate channel 88dB IHF.
 
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Literature describes both (MR74 & MX113) as being Quad Balanced as well as a few other similarities. Specs are similar as well.

I'm no engineering expert but on the surface of things it would appear the MX113 : MR74 what the MX117 : MR75 - which is to say perhaps a slightly simplified version of the standalone tuner counterpart.

* Don't you already own an MX113? Are you considering another?
 
Those links are right from Roger Russell's McIntosh equipment website, but whatever.
 
Those links are right from Roger Russell's McIntosh equipment website, but whatever.
Go back and read them closely.

MX114:
FM SECTION: Sensitivity 2.5uV, Distortion 0.5% in mono, Response 20-20kHz (+1.0 -1.0dB), Capture ratio 1.8dB, Spurious rejection 100dB, Image rejection 80dB,

MX113:
FM SECTION: Sensitivity 2.5uV, Distortion 0.7% in stereo, Response 20-15kHz (+1.0 -1.0dB), Capture ratio 1.5dB, Spurious rejection 90dB, Image rejection 95dB, Stereo separation 35dB. Selectivity: adjacent channel 15dB IHF, alternate channel 88dB IHF.

Literature describes both (MR74 & MX113) as being Quad Balanced as well as a few other similarities. Specs are similar as well.

I'm no engineering expert but on the surface of things it would appear the MX113 : MR74 what the MX117 : MR75 - which is to say perhaps a slightly simplified version of the standalone tuner counterpart.

* Don't you already own an MX113? Are you considering another?
The one I own continues to have problems even after I thought it was fixed. I really want an MR74 and get rid of my 77 but MX113's seem to be cheaper in general.

Also, I thought "quad balanced" was a power amp technology. The only similar phrase I can think of is a "balanced mixer."
 
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Ah yes, the link is correct, but the copied text was wrong--fixed. My apologies.

My previous comment about the MX113 stands, but if you want the best, go for an MX117.
 
I've had a number of MR74s over the years - fine tuner indeed. I spent 6 mos with an MR77 that I had brought to spec and aligned for a friend - my oh my, what a luscious sounding tuner. I prolonged returning it to him as long as I could ... My MR75 isn't even in the same league.
 
Right now I have both of those units with the 113 being freshly aligned. The 74 is by far the better sounding and more sensitive tuner. If you'll be doing any fm listening I'd recommend looking for something other than the 113
 
The one I own continues to have problems even after I thought it was fixed. I really want an MR74 and get rid of my 77 but MX113's seem to be cheaper in general.

Also, I thought "quad balanced" was a power amp technology. The only similar phrase I can think of is a "balanced mixer."

My error - Quad tuned what I meant to say.

http://www.akdatabase.org/AKview/displayimage.php?album=15&pos=2

Since you already own it and it's in mint condition, why not just have Terry or Audio Classics give it a good going over and be done? Besides, who's to say the MR74 you find won't need as much attention or even more?

I wouldn't give up on it this easily.
 
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My error - Quad tuned what I meant to say.

http://www.akdatabase.org/AKview/displayimage.php?album=15&pos=2

Since you already own it and it's in mint condition, why not just have Terry or Audio Classics give it a good going over and be done? Besides, who's to say the MR74 you find won't need as much attention or even more?

I wouldn't give up on it this easily.
Thanks, 64Caddy: You are probably right. The one thing I notice from these replies is that they drift into the subjective world of opinions. From my miniscule knowledge of FM design and reading schematics , the 13 and 74 are identical from what I can see RF-wise. Yet one seems to sound superior to the other.
 
Don't forget that the MX113's tuner output must first pass through the preamplifier section before it can be heard. Anything amiss there will obviously put the MX113's tuner section at a disadvantage right at the outset.

Fully restored, I see no reason why the MX113 shouldn't be as capable and worthy a McIntosh unit as any.

BTW - I think DOB mentioned servicing an MX113 for ABC News anchor Hugh Downs - who had traded in his MC275 + C22 + MR71 in on an MX113 + MC2105.
 
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I had a MX113 and was disappointed in the FM sound quality. Sold it. The MR71 tuber was much better but the ex-wife claimed. Looking for an NR74 or MR77 now.
 
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