MR74 vs MR77

[jlovda]

From the White Catalog I have, the MR74 seemed to be positioned as the "2nd best tuner" in the Mac lineup behind the MR77. Yet many people on this forum give glowing reviews to the MR74 and not so much for the MR77. The MR77 had the new, fancy design including the RIMO IF filters while nothing special was mentioned about the MR74 except variable selectivity. I noticed looking at the schematics that the MR74 also seems to have RIMO IF filters but they don't attach a name to them.

Any comments or opinions?

 

[62caddy]

FWIW - The last price of MR 77 was $699 in 1978; $849 for the MR 74 in 1979 - if cost means anything...:scratch2:

 

[twiiii]

Compared to My MR-80 and 78 the 77 has some definite performance issues, adjacent channel rejection and image rejection, being my complaints. But that being said if the FM band isn't over clogged it will reach out and capture weak signals, has great sound, low distortion and great clarity. A 78 can definitely handle a clogged FM band with and sound great at the same time. My MR-80 does a great job, too, and with my current installations the difference between the two is very small. At one time we had to install MR-73's as thats all was available and I wasn't very happy. They had an edgy sound I just didn't like. The 74 was a great improvement. Much smoother sounding was my experience. The FM station in Las Cruces was using dolby noise reduction and if you had decoder the sound was amazing using the 74. They only had a 1500 watt transmitter as I remember but with a highly directional antennae and as I was over 80 air miles from the transmitter using a stacked pair of Jerrold antennae the sound was terrific. The only problem was there were 12 very strong FM stations in the path way too. So I had to be careful to keep from over loading the front end of my tuners. And this is where 71's, 73's , 74's and 77's failed. The 78 and 80 performed very well. I have since moved and don't need the stacked array. A simple Finco FM antennae in the attic surfices. I imagine the 77 and 74 would work great, now. And in fact the 77 is now in a different location connected to a cut winegard antennae on the other side of the Franklin mountains picking up a reflection off the Juarez mountains to capture the signal from the Las Cruces station and performing quite well, I'm told by my friend who bought my 77 tuner. I have no clue what happened to the 74 I had for a brief period, but I thought for FM performance my former 77 had a slight edge.

 

[Brian]

When I was hunting for a long term tuner, I ran to the quandry as I wanted a McIntosh system knowing it was to last for decades and virtually nothing else at the time came close to hinting it would last as long. My lifestyle was such that pulling in distant stations was not a priority, not at the time in New England was there any overcrowding of stations.

The 78 was ruled out after comparing it to the 77. The sound of the 78 was just not as good but if Dx'ing were a criteria it would have been the winner. The 74 proved far more competitive. I was under the impression the 74 did not use the RIMO filter. Maybe Richard could clarify. In the end the tuners were a virtual draw, with the 77 barely sounding better with classical music from the local university radio station. I went with the 77 also, as it was somewhat less expensive allowing me to step up from the C26 to the C28 with SCR2. The MC250 selection had already been decided on as I had no need or want for meters nor needed the power of the MC2100.

 

[jlovda]

I am really not interested in an MR80. I have an MR77 and received a good offer to buy an MR74. I am mainly interested in deciding whether to keep the MR77 or swap in for an MR74.

 

[62caddy]

Why not just go ahead a grab it? It doesn't sound like you have much to lose if the price is right.

How long has it been since it was serviced and aligned?

 

[twiiii]

He brings up a good point. I had my MR-80 tuned up 3 or 4 years ago by AC and the sound really took a big step up the ladder toward perfection. I think I would have my MR-77 serviced before investing in a MR-74 if I were you. The designer of the 77 and 78 does service work for AC and has some appropriate updates making them both better than new.

 

[kevzep]

MR78 is the best sounding tuner for me, it has nice lush mids and soft, smooth yet detailed highs, and nice solid bass, my other tuner is a MR80 which I find a bit sterile by comparison.....
All the radio stations transmitters in Auckland NZ are on our extremely tall "Sky Tower".....
There are about 30 odd stations and so the airwaves are pretty crowded......
So the MR78 is in its element here, I won't be needing any other tuner for the foreseeable future....
Analogue is here to stay on the NZ airwaves, so no worries about everything going digital....nice....:thmbsp:

 

[62caddy]

He brings up a good point. I had my MR-80 tuned up 3 or 4 years ago by AC and the sound really took a big step up the ladder toward perfection. I think I would have my MR-77 serviced before investing in a MR-74 if I were you. The designer of the 77 and 78 does service work for AC and has some appropriate updates making them both better than new.

That's probably a good idea. RM mods increase the value of the tuner significantly as well.

MR78 is the best sounding tuner for me, it has nice lush mids and soft, smooth yet detailed highs, and nice solid bass, my other tuner is a MR80 which I find a bit sterile by comparison.....
All the radio stations transmitters in Auckland NZ are on our extremely tall "Sky Tower".....
There are about 30 odd stations and so the airwaves are pretty crowded......
So the MR78 is in its element here, I won't be needing any other tuner for the foreseeable future....

Same here except not many crowding problems.

Looking forward to compare with the MR 80 with the 78 when it returns from Terry - next week, if all goes well.

 

[damacman]

I just had an MR77 totally gone through and aligned for a friend of mine. It sounds and performs excellent. It's been in use in my office system for the last several weeks now. I was so happy with it, I dropped of my MR75 to the same guy for a similar treatment. I'm really not sure you'd be gaining much, other than AM, going from the MR77 to the MR74 . . .

I've always been a firm believer that FM tuners need to be aligned to meet / exceed factory specs before you can evaluate one versus another. Sometimes this can be extensive and laborious.

 

[Guest113]

I'm not nearly as technical and most guys on here, here's my 2 cents anyway. I wanted a tuner for a new Mac system I put together recently. I could have bought the TM1 tuner for my MX 119 but that didn't work for me. I figured that if I'm listening to FM I should be listening on a real tuner, with a dial, lights, dials and all the goodies. When I shopped around I couldn't justify spending an extra $500 on an MR 78, hence I bought the MR 77. I couldn't be more pleased. I live at the Jersey Shore, about 60 miles from NYC and Philly. With a dipole antenna in my attic I get crystal clear reception from both cities. The tuner is dead silent, warm and clear. Bottom line: get the 77. You'll be pleased. Good luck.

 

[jlovda]

Thanks for your comments. I'll look into a somewhat local alignment if the servicer has a good Mcintosh reputation. Shipping it somewhere is my last option.

 

[Brian]

Thanks for your comments. I'll look into a somewhat local alignment if the servicer has a good Mcintosh reputation. Shipping it somewhere is my last option.

Call Audio Classics and talk to Richard. He can tell you about his upgrades.. I have heard a couple of his units after doing his magic and for the money, I would just send it to him. He had done the work on my MX110 but no mods as he stated it was the one Mc unit out of the box just could not be improved on. When I got it with his test sheet I fell in love with the 110 again.

There are some well respected Mc techs out there but when it comes to the tuners and somewhat to the preamps, Richard would be my first choice. For preamps, amps, etc. Terry seems the go to guy.

 

[jlovda]

Call Audio Classics and talk to Richard. He can tell you about his upgrades.. I have heard a couple of his units after doing his magic and for the money, I would just send it to him. He had done the work on my MX110 but no mods as he stated it was the one Mc unit out of the box just could not be improved on. When I got it with his test sheet I fell in love with the 110 again.

There are some well respected Mc techs out there but when it comes to the tuners and somewhat to the preamps, Richard would be my first choice. For preamps, amps, etc. Terry seems the go to guy.

First, I would have to say that I cannot hear grass grow. I had my MR78 aligned by Terry D. after an ebay purchase and was quite happy with the results. I now cannot afford to spend about twice the price of the tuner for an alignment using one of the noted experts. I was hoping some of the posters here that CAN hear grass grow could offer opinions on the difference between two properly aligned units (74 and 77). I am probably more interested in RF and IF performance since to my ears all Mac tuners sound spectacular with strong signals.
Thanks

 

[mpholland]

I went with the 74 just because I listen to AM on a rare occasion. I love the sound of it, but I wouldn't know if it sounds any better or worse than a 77. I'm not even sure if there is a better or worse sound...different maybe. If you want to fly over for a visit I could probably borrow Gibson's 77 and do a comparison.

 

[Vinyl Rules!]

MR74 History & Design Team Info

BIG SNIP

Any comments or opinions?

Yes.

Please read https://groups.yahoo.com/neo/groups/Mcintosh_audio/conversations/topics/254 and https://groups.yahoo.com/neo/groups/Mcintosh_audio/conversations/topics/1665 in the old McIntosh Group in Yahoo that's been taken over by spammers.

To summarize what we learned (and heard) when we posted this,

The design of the MR74 was group effort. Jean Filon designed the RF front end and MPX decoder. Richard Modafferi did the FM IF. Ron Evans did the AM circuitry. Mile Nestorovic did the Audio & Power Supply. Some of you may remember that Mile Nestorovic designed many of the early Macintosh tube amplifiers which may account for why we happen to like the sound of our MR74 so much. We don't know if Mile or someone else designed the Audio and Power Supply of the MR77 and the MR78, but we can only speculate that perhaps Richard Modafferi did more of the total design work on these two tuners since they were his "babies."

From a filter perspective, McIntosh literature states the MR74 has a 10 pole filter in the "Wide" setting and we incorrectly assumed this meant the MR74 used a 10 Pole RIMO filter, but this is not the case: The MR74 uses exactly the same 8 pole RIMO filter as found in the MR77, but it is preceded by a 2 pole bandpass filter. They're two separate filters and they are cascaded. This explains why the specified distortion is slightly higher on the MR74 than on the MR77.

The MR74 in "Narrow" mode switches in a single ceramic filter. This adds a little extra selectivity - not much. It is thought to be a \2 Pole interspersed between the 2 Poles in the RF and the 8 Poles in the IF filter.

The original MR77 prototype used a 10 Pole RIMO – but there's only one in existence – and Richard Modafferi has it. The production MR77 used only an 8 Pole RIMO filter and Jeff advised us the MR-77 does have slightly better phase linearity than the MR-78, which may account for the slightly better sound quality associated with the MR77 relative to the MR78.

Since that time, we've had the opportunity to compare a refurbished unmodded MR77 to our own refurbished unmodded MR74.

We expected the MR77 to sound a bit better because it has only the 8-pole RIMO filter in its IF section versus the 8-pole RIMO + 2 additional poles of IF filtering used in the MR74's "wide" setting.

However, the power supply and audio output circuit is a different design in the MR74. Miles Nestrovic (sp?), a famous McIntosh amp designer did the design of the power supply and audio output circuit of the MR74 whilst Richard Modaferri did the complete design for the MR77.

Not to diminish Mr. Modaferri's accomplishments with the MR77 and the MR78, we thought the MR74 actually sounded better in a side-by-side
comparision with the MR77.

This was NOT what we expected - We began the comparison with the expectation the MR77 would better the MR74, and it did not. So we can only assume that what we heard was a demonstration of how important the power supply and audio output secton is for a tuner. Mr. Modaferri's expertise is in the IF and RF design of a tuner and Mr. Nestrovic's expertise is in amplifier design.

We have come to the conclusion that the MR74 incorporates the work of McIntosh's best ever tuner designer for the IF and RF front end and McIntosh's best ever amplifier designer for the power supply and audio output section. This is why we think the MR74 sounds better even though the IF section is, in theory, a more simple design on the MR77 than on the MR74.

As always, YMMV.

 

[damacman]

Excellent explanation Vinyl Rules. I've had a few MR74s and they are indeed excellent sounding. Of course without doing a live comparison, as you have, it's simply speculation on which is better. They're obviously both capable of excellent performance.

 

[jlovda]

Thank you very, very much for the history lesson. This was one of the best and most thorough explanations I have ever read!!

John

 

[jlovda]

One additional question:
The MR77 and MR78 utilize the unique bridge discriminator with the coiled up coax cable. Is it really that much better? I noticed that the capture ratio is much poorer on these two tuners.

Also, after the 77 and 78, no tuner seemed to utilize the FET-Bipolar design in the front end to prevent overloads. Was this an overkill design?

 

[doug s.]

i have owned and listened to more than 100 tuna chez sedon. the mr77 i owned - refurb'd and aligned - was the 2nd worst sounding tuna i ever heard. the mint never serviced mr74 was not quite as bad, but almost.

now, i am not someone who has anything against mac (or any other brand, for that matter); i yust call 'em as i see (or hear) 'em. i owned a refurb, modded and aligned mr65b, (stephen sank does great work, if you are patient and don't need it quickly), and it was very good sounding. the 74 and the 77 had much better reception, but the 65b actually sounded nice. still over-priced, imo, as the sherwood tubers - s300ll and newer - still sound better than the mr65b, with nominally better reception as well.

doug s.

ymmv,

doug s.