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Reviews 1 - 2 (2 Reviews Total)
a Audio EnthusiastDate Reviewed:
May 3, 2006Bottom Line:
I have an original Model 9.
What an amp!
In one word, amazing!
Puts to shame all the Hi End business!
Used product for: More than 1 year
Duration Product Used: Audio Enthusiast
David L. Winebrenner
a an Audio EnthusiastDate Reviewed:
June 4, 1999Bottom Line:
This all goes abck to 1963 when I used to work at a high end audio dealer, now 'defunct' in Houston while attending the U of H there. The resident dyed in teh wool audiophile there was Woody Tottenham a UT med. student at the time loved Marantz and he had finally gotten the boss to go along with ordering a pair of Marantz model 9 power amps to demo and sell from. OK so finally they came in and Woody wouldn't let anyone else touch the boxes until he had time to carefully unpack them. This was back in teh time when Sol Marantz still personally owned the Marantz factory (then in Woodside N.Y.) He had them unpacked and on the floor with the bottom plates pulled off. I saw the most amazingly neat point to point wiring and interconnection I had ever (or since seen. (not at all like the rather crudely wired McIntosh stuff that I was used to seeing. He brought in a couple of AR-3's and unpacked tehm and we proceded to listen to the 1960 Reiner/Chicago symphony RCA open reel tape of the "Also Sprache Zarusthustra. A truly wonderful performance long before the '2001 craze' with pieces of the same music by the Berlin Philharmonic hit some years later. Overall a very nice 'silky' sounding amplifier.
Each one had a glorious champagne colored brushed aluminum front panel that just exuded class. Some months later the McIntosh amplifier clinic came to the store.(Dave O'Brien was the guy they sent around from the Mac factory in those days). Anyway at teh end of teh last day when things fionally slowed down on the clinic, Woody pulled the two Marantz model 9's down off the demo shelf and hauled to the clinic bench and had harmonic distortion curves run on them. In a Mac clinic in those days it was common practice to tape a copy of each curve that had been run in the clinic on the inside of huge expanse of glass windows that the shop had in front. By then the large floor to ceiling windows wer completely full of charts on other amps that people had brought in for test. Of all the hundreds and hundreds of charts, the Model 9's were the only amps that had a flat line at the bottom of the chart with a notation about 20KHZ being ,08%, 1KHZ being .06% and 20 HZ being .09% at just before clipping (82 watts each at 8 ohms) (Of course Woody had tweaked the bias reading on the regular service bench in the back of the shop before bring them up to the Mac clinic bench.
The curves on the Mac MC275 stero amps and MC75 mono amps measured in the clinic all had between .25% and .45% harmonic distortion at 20 and 20KHZ. This is a huge percentage differential although both are still quite low overall compared to the typical distortio of most source material of the day (Prerecorded tape, .5%-1.5% at 0 VU, and records at something far higher at best and FM broadcasts which were never wonderful in Houston). Woody brought one of them back to teh bench again just before starting to pack jup the equipment to leave and this time had the selector set for triode mode. The power was lower at 45 watts, but the distortion fell even lower don into the .045% and .05% range which is absolutely as low as you can measure on an old Hewlett packard 330B distortion analyzer that was used back in those olden days. Woody was in pure 'exctasy' over this and O'Brien could see he was very biased toward Marantz so Dave went over asked JRC, the boss is he could open one of the 2 new MC75 mono amps in stock and JR said 'sure as long as you get it sealed back up properly'.
OK.....the battle was on, with one Model 9 still on the bench and a brand new smelling MC75 opend and placed next to it the test battles began. first O'Brien hooked up the MC75 and ran the old HP 200CD signal generator down to 16 HZ (then called cycles per second). then he ran the amplifier up to clipping which was a really amazing 105 watts and mad a distortion measurement and it was still right at .27% and then he switched the 9 back over to pentode mode and at 16 HZ it did 55 watts at .8% harmonic distortion. THen he ran the Mac down to 10 HZ and it still did 60 watts and a not so terrible .5% harmonic distortion. Then he ran the Model 9 down to 10 HZ and it would only do 32 watts at about 1.3 % harmonic distortion. He then went down to 8 HZ and the MC75 did 45 watts (about 3.2 db below normal full power) at .55% or so distortion. he then ran the generator up to 100KHZ and the Mac did 90 or 92 watts and the Marantz did 70 watts but the distortion on the 2 was about the same at .5% harmonic.
Woody contended that the Marantz would outperform the Mac on a real inductive speaker load The Mac test been use dnon-inductive pi-wound wire load resistors in stead of speakers normally), so a pair of AR-3s were hooked up in parallel to the 4 ohm tap and the same low end tests were performed as before (you can't run the high end this loud continuously becase it will destroy AR tweeters at anything more than about 10-20 db below this high level. The result? A you could have guessed the Marantz and the Mac both performed worse on the inductive load of the paralleled AR3's. (both were typically half again worse on this highly inductive and variable load.) Then Woody went over and switched the Marantz to triode mode and the distortion once again dropped down to practically as low as could be measured with that rig (mainly due to the internal circuit noise of the old 330B analyzer, which was around 95-98 db below the level of these amps being tested. Woody smiled and said "see Marantz is better and O'brien said '...but this is only doing around 45 watts in triode. So he hooked teh mac back up and ran it at 45 watts in the only mode it had (pentode mode) and made teh measuremnts. The Mac did drop to around .15% harmonic dist., but woody said 'yeah but that is still over twice as nuch distortion as the Marantz.....And so that was teh end of the tests. O'brien packed up the lab and flew to the next clinic and we all returned to our daily tasks in the days that followed.
I could not help but think about all this and finally came to the conclusion that the manufacturers all really know where they excel and where they fail. It is too bad we didn't have a Marantz engineer there to really make the tests totally fair and balanced. There are many more interesting and thought provoking things that happened in those wonderful days of what is now know of classic equipment. Which would I really rather have, the MAC MC75's or a pair of Model 9's? It is really hard to say. The model 9's of course are much more rare and pricey now. I would probably say that you could do almost as well with a pair of Marantz 8b's (40w/channel), bridged each for 70-80 watt mono, except for the extreme low end test, and for a whole hell of a lot less money than the 9's (they are somewhat uglier with no front panels).
We now know of course that the unity coupled McIntosh approach is a little easier on tubes and runs them slightly cooler than the Marantz design did so..the output tubes on the Macs generally out lasted those on the Marantz units. That does come in handy in this day and age when you can't go down (anymore) and buy EL34's or KT88's as easily (or as cheaply) as you could in those days. Listening to both amps on Klipschorns there didn't seem to be a lot of difference, bit on KLH model 9 full range electrostatics the Marantz units had a distinctly 'sweeter' and more clean, clear sound characteristic. In triode mode the 9's were noticeably better sounding on the above full range KLH electrostat speakers when we brought in one of Bill's orchestal master tapes done with Omega condenser mics on an AMPEX at 15 IPS, (that was the best source we had in those days) and played the Marantz amp in triode with 4 KLH model nine electrostats in parallel one night late it was probably the best sounding systems (to me) I have EVER heard.
I must say also that Bill's master tapes did compare favorably with the best of the digital recordings of today I still have copies of a number of them. (but practically no one had this kind of material to play in those days).
Duration Product Used: an Audio Enthusiast
Reviews 1 - 2 (2 Reviews Total)
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