New 501s

Doing some serious jazz tonight with my wife...Bill Evans is right..over...there!

They have kept most of the magic smoothness of the 275 and added a new level of clarity in the bass region. I am hearing more details in the kick drum and bass guitar than I have had since my big Yamaha days.

And once again the 250s are there to tell me exactly what changed upstream...they are doing a pretty good job of being an audiophile speaker tonight after letting their hair down and partying hard with the 501's last night. You could almost hear them daring each other:

'c'mon I can take more than that'

"ok here you go then...get ready"

'seriously..you need to get to the gym if that's all you got'

"ok tough guy...how about now!"

'bring it!'

lol

jblnut
 
Doing some serious jazz tonight with my wife...Bill Evans is right..over...there!

They have kept most of the magic smoothness of the 275 and added a new level of clarity in the bass region. I am hearing more details in the kick drum and bass guitar than I have had since my big Yamaha days.

And once again the 250s are there to tell me exactly what changed upstream...they are doing a pretty good job of being an audiophile speaker tonight after letting their hair down and partying hard with the 501's last night. You could almost hear them daring each other:

'c'mon I can take more than that'

"ok here you go then...get ready"

'seriously..you need to get to the gym if that's all you got'

"ok tough guy...how about now!"

'bring it!'

lol

jblnut
Well that was my finding as well, as soon as I got them I could tell the percussion's improved immensely. Then with all that head room you also get fantastic mids and highs.

They shouldn't sound as bassy as my phone recorded clips but much tighter sounding in person.

I guess this is your new pair of speakers you where looking for?

Thank God, it's only taken you three years of me telling you, more power is better, but the 501s are better power than most :p
 
I remember my intro to the MC501 monoblock amplifier...actually a pair of them...

William Shakespeare penned the line, “Who seeks, and will not take when once 'tis offer'd,
Shall never find it more.” for his play Antony and Cleopatra in 1606. Was he paraphrasing, “Opportunity knocks but once” or was it the other way around? No matter. But such historic phrases and lessons learned should not be ignored, even by those of us who lust after audio nirvana.

A case in point – Years ago I purchased my first “high end” system. Figuring prominently in the wood produce crate and cinderblock audio rack were a pair of McIntosh MC250 amplifiers and a MR77 tuner. While the rest of the system has faded into distant memory, I will never forget the experience of owning that McIntosh gear and the musical joy it brought to my life. Sadly though, I lost those components to a light fingered roommate and moved on to other gear and newer technology.

Fast forward more years than I am willing to admit to and I am repeating my audio history and once again have purchased McIntosh audio components because Opportunity came knocking.

Today’s subject is the massive, powerful and weighty McIntosh MC501 amplifier. McIntosh introduced the MC501 in 2003 and it enjoyed a 10-year production run, becoming a favorite amongst audiophiles far and wide. At over 9 ½” tall, 17 ½” wide and weighing in at 91 ½ pounds unboxed, they are indeed massive. You better have sufficient room in your rack for this beast. Better yet, putting them on isolated stands on the floor works pretty good because without a small crane or some strong helping hands, you won’t be lifting and carrying them very far.

Power comes from a burly and conservative design, with the amp capable of delivering 500W into any load between 8 and 2 ohms and it's rated to deliver more than 100 amperes of output current. I’ve been told in a pinch a pair of them can double up and be used as a welder but I’ll leave well enough alone and not test that particular myth. I purchased them specifically to provide electrons to my speakers and they should do that very well.

McIntosh is well known for producing distortion free power at high levels. I can’t imagine that 500W would be insufficient to drive any speaker but the key here is the level of quality to provide that power with no distortion. In reading the manual, I noted that McIntosh states "an automatic tracking bias system completely eliminates any trace of crossover distortion," and "precision metal-film resistors and low-dielectric absorption film capacitors are used in all critical circuit locations."

The manual goes on to describe the circuitry as a “Double-Balanced Push-Pull” design with both sides of the amplifier being fully balanced and all four output signals eventually coming together at the Autoformer coupling transformer. I’ve been told the “Double-Balanced Push-Pull” term is now referred to as “Quad Balanced”.

I only mention those technical bits to provide the obligatory “tech speak” for the technically oriented. We could go on and on and on regarding other aspects of this technical wizardry but to be honest, most of this is way beyond my ability to absorb and analyze. However, homage must be paid to the McIntosh engineering group for translating the technical bits into musical excellence.

The units positively gleamed as I unboxed them, with the large blue meter featured prominently in the center of the black faceplate. With some very capable help, I placed the MC501’s in my Salamander Twin 30 rack system and made up the connections. Sending signals to the MC501’s is my MX135 pre-amp and further upstream in the electron path we have a McIntosh D100 pre-amp/headphone amp/DAC that is utilized as a DAC only in this system. The D100 connects to a Streacom-cased, Windows based home built audio server which is attached to the network and remotely controlled via laptop at my listening station.

Cabling throughout the system is primarily Wireworld products of the balanced XLR, optical and coaxial type. The Acoustic Zen Satori bi-wired speaker cables round out the wiring. I would be remiss in not mentioning that tuner duties are handled by a McIntosh MR85 and there is an Oppo BDP-93 available for spinning CD’s. Most of my music listening, though, is high resolution FLAC drawn from the server. The sound ultimately emerges from my Aerial Acoustic 8 full range speakers.

The Aerials require a firm hand to drive the 10 inch woofers located in their own 61 liter enclosure at the base of each speaker. Bi-wiring them with a 12 gauge sized piece of copper on each side of the circuit seems to suit them best but you had better be prepared to back up good cable with some power and the MC501’s should deliver exactly what these speakers need.
 
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The first time I powered up the amps they sounded terrible. What? Terrible? Yes, terribly harsh, muddy, noisy, confused and generally very unpleasant. I surmised I had made a mistake in the phasing but all connections were as they were supposed to be. Then I realized I must have purchased a pair with very few hours of operation on them plus they were cold from sitting in the garage for almost a week. So I resolved to give them some playing time and a warmer environment in which to do so before I passed judgment. I have since decided to leave them on permanently, turning off the meters and removing the triggers, letting them stay warm and ready to go.

As the hours of operation increased, the sound blossomed into a wide ranging, extremely deep and all enveloping experience of exquisite musical ambience. I became so involved in listening that I almost forgot I needed to compare what I was hearing to what I was used to hearing before I forgot my prior pair of amps all together.

I gathered a short collection of songs well known to me that possess significant detail. I decided not to try an A/B test in this instance. The other amplifiers are also too heavy to be moving in and out of the rack and they are about to sent off to a new owner. Queuing up for this test were:

1. Jennifer Warnes – Ballad of the Runaway Horse – Rob Wasserman’s “Duets” CD – 16/44.1 FLAC. This song, covered by several artists including Emmylou Harris, was written by Leonard Cohen. This cover features Jennifer Warnes, showcasing her clear and clean voice as lead and harmony, with simple musical accompaniment. There is a strong acoustic bass line, when reproduced correctly it is in direct contrast to the light instrumentals surrounding it. The MC501’s present this bass line wonderfully and you feel it as you move deeper into the lyrics of loss and renewal.

2. Boston – Cool The Engines – Third Stage CD – 16/44.1 FLAC. One of Boston’s lesser known works, it describes an analogy of slowing down and chilling out, told within the context of a fast and furious spaceship ride in which the engines are at risk because if we don’t slow down, “we can kiss it all goodbye.” Boston is known for a guitar sound likened to an “armada of axes” as lead guitarist Tom Scholz described the effect of his Rockman amplifier and this track prominently features the armada along with a slow, almost languorous bass riff holding things together.

3. Mark Knopfler – Sailing to Philadelphia ( CD) – 24/48 FLAC. Mark Knopfler joins with James Taylor on the title track, which deftly explores the relationship between Mason and Dixon, two English surveyors who came to America and established the border between Pennsylvania and Maryland, Delaware, and Virginia in the 1760s. The border later became known as the Mason-Dixon Line. The track features Knopfler’s signature guitar styling and the faintest of drums expertly rendering an English folk music rhythm in soft counter point to the guitar’s downbeat presentation.

4. Emily Barker and The Red Clay Halo – Nostalgia – Fields of June EP – 24/88 FLAC. An ex-pat Australian living in Cambridge England, Emily Barker formed The Red Clay Halo with all-female trio of Anna Jenkins (violin, viola), Jo Silverston (cello, bass, banjo, saw) and Gill Sandell (accordion, piano, flute, guitar) in 2005. Their music is a distinctly folk in temperament with English influences, open, honest and light with an airy presentation dominated by classic instruments played so lightly as to present an almost acapella style full of vocal nuances.

5. Ray Charles – Here We Go Again – Genius Loves Company EP – 24/88 FLAC. Ray Charles and Norah Jones team up on this Emmy Award winner, which was included on the last album recorded by Ray prior to his death in 2004. A soft drum beat, 60’s style organ background and lilting piano lead blend seamlessly to immerse you in the heartbreak of love and loss, then love found again.

6. Eagles – Hotel California – The Studio Albums 1972 to 1979 – 24/96 FLAC. Don Henley’s raw and raspy style presents the Eagles interpretation of “the high life in Los Angeles”, supported by Don Felder and Joe Walsh’s epic guitar interplay, conveying a sense of driving into LA at night, seeing the glow of its many lights strewn across the landscape.

7. Wycliff Gordon – St. Louis Blues – Audiogon Presents The Wake Up Your Ears Sampler EP – 24/192 FLAC. Wycliff Gordon’s Audiogon special presentation features rising and falling clarinets pushed forward on the backs of a slide trombone with an ever so slight mamba flare, trumpets and bongos moving the music with a quick beat and, oddly enough, a banjo providing a lilting counterpoint ushering in a more traditional St. Louis blues trombone and trumpet melody.

As with any good system, inherent limitations of the lower resolution files are apparent but even a 16 bit file is presented by the MC501’s with space, weight and detail not heard with my previous amplifiers. These amps have a very low noise floor with space – and darkness – between the instruments and voices. They are so precise and detailed that placement of the performers on stage or in the studio can not only be discerned, it’s as if the amplifiers help you to see everything with their presentation.

The upper ranges sound light, airy with no shimmer or harshness to be heard. The clarity, detail and presence are intoxicating and delightful to the ear with all the body and tonal decay you could ever hope for.

The midrange is where the MC501’s shine. There’s a liquidity and wholeness to the midrange that is often found in tube amps, but rarely in the solid state variety. Luxurious best describes the mid-range quality but the luxury does not diminish the detail and precise reproduction the MC501’s are capable of. They will evoke an emotional response to the music that you may find yourself unprepared for.

The MC501 delivers weighty and well controlled bass with an ever-so slightly rounded leading edge. The transients of bass instruments are no less precise than those of upper-midrange and treble instruments, instantly responding to the demands placed by the bass line. They definitely grab hold of the woofers in my Aerial Acoustic 8’s and keep them actively engaged with the music. They put out 500 watts, but we’re not talking about tinny sounding, marble in a can rattling watts. This is serious power, the type needed to control the bass without sacrificing the mids and highs.

The power the MC501’s possess, enabling them to present all the music has to offer, with force and detail when called upon to do so, is amazing. Even so, their performance seems effortless and without strain. There is no large amount of heat generated by these units, even when asked to power the speakers at high levels for extended periods of time. While I hate vegetable analogies, “Cool as a cucumber” comes to mind.

The MC501 amplifier is a shining example of McIntosh’s focus on no-compromise design and manufacturing standards. Their sound quality would best be described as tube like, with detailed and warm highs, a full and expressive mid-range and an impressive control of the lower octaves.

McIntosh has been in business over 60 years. It’s refreshing that, unlike so many other companies, McIntosh has not lost their way and continues to build upon their reputation of supplying high quality, well-engineered and impressively performing audio equipment.
 
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Well that’s just swell!! Glad it all worked out, there’s nothing like loading a few hundred lbs of Mcintosh iron in to the back of your vehicle and just dying to get home to hook them up!! Congrats and enjoy in good health!! :beerchug:
 
Just enjoying sonic bliss here...they continue to amaze and impress at all volumes with any source or genre.

If I was to pick a word....effortless? transparent? or more to the point...permanent.

Thanks for shouting their praise all these years. Some of my best components I have because of passionate praise heaped on them by members here. You'll be permanently associated with these the same way theophile is with my GT2000.

Someday maybe you'll join us in non-suspended DD bliss :)

Jblnut
 
The 501 is a very special amplifier. You can mis match the impedance driving 4 ohm speakers from the 8 ohm tap and the amp will still meet specs producing al most 700 watts. Talking about current capability, the 501 really shines. Whats special about a 501 is how well it performs below 10 watts has been my experience. With that very wide dynamic range and fantastic signal to noise its quieter below 10 watts than a MC 275 could ever hope to be and that even includes the 2301. So if you have efficient speakers and can keep an eye on the the throttle 501 will still be the amp of choice. I'd love to hear a Pair of JBL 4435's being pushed by 501's or even a pair of DD67000. Klipsch says his corner horns can tolerate 400 watt peaks, thats almost 128 db.
I'd love to hear (feel) a recording of UP 4014 after she's restored pounding the rails with that set up. I have some Original Master recordings of 8444, 614 and 4449 I would like to hear some day with a pair of XR 290's and the 501's big cousins, the 1.2 or 1.25 K.
 
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What I really enjoy about my 501's is how they manage the bass frequencies. My Aerial Acoustic 8's need a powerful and well made amplifier to reproduce a tight bass line and the MC501's provide that.
 
On the subject of taps, I am running the 250Tis (6 ohm) off the 4 ohm taps. Is this the correct/recommended setting and does it even matter given the autoformers?

jblnut
 
I would expect that the ohms still dip below 6 at certain frequencies, so I’m sure it’s fine. There’s no harm in trying the 8 ohm tap to see what you like better.
 
The 4 ohm tap is perfect for those speakers since, as joeinid said, they can dip below 6 ohms. My speakers have that 10" woofer in the base and since I am bi-wiring the speaker cables, they need that 4 ohm power to shine.
 
On the subject of taps, I am running the 250Tis (6 ohm) off the 4 ohm taps. Is this the correct/recommended setting and does it even matter given the autoformers?

jblnut
Like you, I have L250s that have the factory kit Ti conversion, and have always been under the impression that they were 8 ohm speakers. Searching online for 250Ti specs, I can't find any evidence that contradicts that. Are you sure they are 6 ohm?
 
I'm not sure actually - the label on the back says 6 ohm but then again that's the label for an L250 which is what mine started as before the conversion.

Maybe I'll try the 8 ohm tap at some point....

jblnut
 
I must be losing it....mine say 8 ohms too. Somewhere down the line I got the idea these were closer to 6 as my crossover networks (each speaker has two now) are not stock. Gotta dig through some old threads on the Lansing site...

jblnut
 
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