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Whoa, Bass Difference With MR71 Swap


Gilbert

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Another Stupid question by Mua'....

About a month ago I picked up a crispy clean MR71 that had just been serviced by none other than R. Modafferi. I had kept it wrapped up until last weekend, when I finally had time to swap it out with my other one, and give a listen.

Now she's been playing for 2 weekends, and I am very surprised to notice a distinct increase in the low range, and even the mid-range appears more dynamic.

Anyway, my question is. Why does the resently serviced unit dig into the lows that much better? What tubes are responsible for this improvement? I thought it was the preamps job of doing that, and that the tuner just grabbed the signal.

Sorry for the dumb question(s), but I am so impressed, and I'm now ready to ship my original unit off to Richard.....as soon as I garnish some more $$$. I even gave her a good waxing and wrapped her up in the box, ready to go, next month.

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Gilbert,

There is alot more to Tube amps, Preamps and Tuners then the tubes. From what I know of R. Modafferi he does some extensive mods to the MR71 and I'm sure those modifictions are mostly what your hearing. Then it also could be that your other MR71 is simply not working properly weak power supply, leaky coupling caps, poor alignment and on and on could really hold the old girl back.

Craig

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I'm told that Richard's mods bring very impressive sonic results, and your comments mirror many I have read. I consider from time to time having Richard work his magic on my MX110. Having Richard do a rebuild is like "rebuild deluxe" - it's as far as one can go with such a unit - as close to having Mac reissue your unit as one could get, by someone who knows as much about Mac as anyone.

I have yet to hear from anyone who WASN'T satisfied. And that says something, 'cause Richard isn't cheap.

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I've got an MR67, which was updated by Paul Grzybek in Chicago and the

bass improvement was the first thing I noticed when I got it. Much more

solid than any other tuner I've tried to date. And voices, oh so

natural. I think it must do to being in proper alignment. I also had

quite a few of the old caps changed, and all the tubes checked out.

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For someone like me, who knows very little about this stuff, it is really mind numbing. Tube wise, both units are bone stock, and I mean identical, tube for tube, I had to check after the listening comparison. All factory original. I came to the conclusion that the difference was probably due to some weak tubes in my original unit. The condition of my original unit is 98% almost perfect, only some swirl marks on the chrome and some slight/trivial oxidation specs at a couple locations. The other unit which Richard Modafferri touched, looks brand new. It is absolutely perfect, and to be honest, it is the only reason bought it. Astetically and sonically, it is a show piece, absolutely perfect.

What ever Richard did to this unit, it is considerably better sounding than my original, it's hard to explain, and I just cant believe it's FM radio. Oh how I'd love know and understand half of what that man has forgotten in his life time.

Craig, I'll have you know I bought this second MR71 to mate up with my future VRD's, and the my BB soon to be Xtreme. I don't know what I'm gonna ask for on the VRD's, but I'll want something special, different, better than the originals. If you have any experimental ideas, or suggestions let me know. As far as your wanting to study and look over the MR71, I will be happy to let you scope out my original MR71 before, and again after it get back from Richard. Take all the time you like, and you can send it back when the VRD's are ready. In fact, I'll ask Richard or audioclassics (not sure how it works, since he's an independent) to send the Modafferi modified unit directly to you.

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One thng could be the preemphasis, or is it deemphasis circuit.

When a record is cut, or the FM signal transmitted, the highs are boosted. There is some noise on a record platter and the radio process. Either the high frequency noise is more annoying or there is more of it (maybe both). So the treble is up out of the noise.

Then at the phono preamp, or the FM receiver, the highs are cut. The normal treble program is reduced back to normal and the noise in the transmission - storage media is reduced below "normal".

He might be playing with that.

These comments make me think I should send in my Mac. However, my main problem is multipath.

Gil

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