System
07 July 2002
"Re-Visit":
20 April 2003
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System |
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07 July 2002 "Re-Visit": |
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Jan Hofman |
"The halcyon days of the 60s got me interested in audio equipment. I was in college and my apartment was the on-campus drop-in center. I had huge parties once per month (even professors and administrators enjoyed them) and needed lots of volume and bass. I didn't have the money to buy great speakers, so I learned to build them myself. People loved them and sooner or later, I would get an offer I couldn't refuse. I poured the money back into audio equipment, and half a dozen speaker systems later, I had some very decent equipment. There was no going back to dad's Zenith console after that. Since then, I've bought and sold many fine pieces. Those which still bring warm memories are Dynaco A25XL speakers, early Sound Dynamic speakers, a Quad 33 & 303 combo, a Sansui 717 integrated amp, a Robertson 4010 amp, a gorgeous brushed-gold Empire turntable, Wharfedale sand filled enclosures, and a Grace F9E cartridge with a Ruby stylus. The basis of my current system is a pair of Newform 630 speakers. The 30" ribbons are the best tweeters I've ever heard. Since they cross over at 1000 Hz., perhaps they are more accurately described as tweeter/midranges. Nothing I've ever owned has brought the live performance into my living room like these 3/4" monopole ribbons. Their beveled housing is only 3 1/4 inches wide, so diffraction problems are a thing of the past. Their height and unsurpassed dispersion presents a "wall of sound" much like one hears in a concert hall or night club, but without the shortcomings of large panels (beaming, backwaves). Their imaging and resolution make it easy to get lost in the music. The ribbons were reviewed in issue 102 of The Absolute Sound. The reviewer, Aaron Shatzman, was "awestruck, speechless, by a purity, clarity, and awareness of detail beyond any experience." He was less enthused about the 8" Peerless driver used in the bottom end, which has since been replaced by the manufacturer with a better, but still unsatisfactory, Scan Speak 8545. These drivers sound good in some of the finest systems around (ProAc, Wilson) but their limitations in imaging and resolution are glaringly obvious next to the Newform ribbons. After considerable experimentation, I finally settled on a 7" Accuton (Thiel) ceramic driver. The Seas magnesium cones were detailed but too harsh, the Focal W series were very dynamic but lacked body, the Triangle cones lacked dynamics. The ceramic drivers have the best resolution and make the best compromises (albeit at a price). I'm told these are the same drivers as used in the $65,000 Kharma Reference 1B speaker system, which Jonathan Valin in issue 125 of The Absolute Sound described: "... this piece of china conjures up the presence of real instruments in real space as persuasively as anything I've heard ---planar, 'stat, or cone ...... it may well be the most natural sounding midrange you can buy." Nothing aside from the source material has more influence on a system's sound than speakers, and money spent there is infinitely more effective than money spent on electronics. As I have a Behringer electronic crossover, matching different drivers to the ribbons was easy. Matching them to the room was also easy, for which I use a Behringer digital equalizer. Both these components can be bought for less than $1000, and their contribution to overall fidelity vastly exceeds the trivial improvements I've realized through upgrading amps, pre-amps or front ends. I have a Parasound PLD 1100 pre-amp which I like for it's convenience and appearance. Like most good pre-amps (I had a Cary tube unit before this,) it adds or subtracts nothing audible to the signal except amplification. Likewise for the amp, a five channel Sherbourn model 5/1500. I bought it because of its prodigious power (200 watts per channel,) its price, and the fact that it has separate power supplies for each channel (like Bryston). Roger Sanders, designer of Innersound products, claims that the primary audible difference between well designed amps is in their power rating, and this amp just cooks. I have 200 watts running to each ribbon, to each Accuton driver, and 200 watts to an Adire Audio 15" Tempest sub. The benefit of big power is effortless, crisp transients and non-fatiguing sound. By the way, I take credit for indirectly introducing Roger (through a mutual friend) to Behringer equalizers, which Innersound now distributes. Despite the protestations of "experts," Roger says they have no audible negative effect on the sound. The positive effects are the elimination of room modes (one note bass, screeching vocals) and bass extension --- great organ pedals. The EQ has a built in real time analyzer for automatic room equalization (using the microphone) and stores several dozen curves. I use customized curves for different source material to compensate for the biases of recording engineers. I built the sub myself out of an 18" cardboard tube used to pour concrete pylons (think Hsu). It is in a corner next to the listening position. That gives me maximum output and dispersion. The digital EQ takes care of frequency anomalies, and the crossover permits a 2 millisecond delay, which compensates for the difference in distance between the monitor speakers and the sub. Many of the audiophiles who come to my house are not even aware of the sub, it's that acoustically transparent. I cross it over at 75 Hz. (4th order Linkwitz/Riley) which is also where the Accutons cut in. This method relieves the ceramic drivers of serious bass duty thereby improving midrange resolution. They are crossed over to the tweeters at 950 Htz. I recently bought a Pioneer DV 440 DVD player for the bedroom TV. For fun, I plugged it in to my stereo system in place of my Dodson DAC and Rotel 980 transport. To my surprise, it sounded every bit as good, possibly better on some material. Friends confirmed this. Comparisons with other expensive CD combos produced the same result. I'm told it has a good 24/192 Burr/brown DAC. I've since sold the Dodson and Rotel and use the Pioneer exclusively. A tweak not visible in the photos are the use of 25 foot runs of 28 gauge speaker cables --- even to the sub. I use 83002 009 Belden cable, which is silver plated copper with a Teflon di-electric. This was recommended to me by an engineer, and it sounds cleaner and more dynamic than any of the pricy garden-hose cables I tried. The amplifier manufacturer assures me that this cable is perfectly adequate for 200 watts. Some of you will be incredulous, but just try it! My interconnects are Radio Shack gold cables available for about $20 each. I tried many different interconnects, and they all sound the same to me. We've tried some experimentation with a group of audiophiles, each bringing his own interconnects, and in A/B comparisons, no-one could consistently identify their favorites. Despite being very well built, most speaker cabinets still vibrate. The energy has to go somewhere. If the cabinets were built of solid stone, the backwaves would be fed back out through the driver, not a good solution. So what is? I've placed a flower pot containing 20 lbs of construction (beach) sand on top of each monitor, and 50 lbs on the sub. Unlike a brick, the sand moves in response to vibration and converts energy to heat. Vast (cheap) improvement. I've also removed the spikes from the bottom of the cabinet. Spikes actually increase cabinet vibration. Imagine a Harley idling on a concrete floor while sitting on its centerstand. Because there is no absorption through the floor, the bike's tank, gauges etc. rattle violently. Place the bike on its tires, and everything settles down. Why would it be any different with speaker cabinets. Place them on a carpet or on some rubber pads, and let them absorb the vibration rather than feeding it back into the cabinet. The proof is in the pudding, and although many of the local audiophiles have spent infinitely more money than I, most agree that my system is outstanding, especially on full orchestral music. Whether it be Copland's Third Symphony or the Gladiator soundtrack, this system is exceptionally dynamic, revealing and smooth even at high volumes, where most systems fall apart. Voices like Patricia Barber have astonishing presence, and every individual voice can be delineated in well recorded choral works, including those that miss a note. That's probably it's downside, this system reveals flaws one may not want to hear. Were it not for the EQ, many of my recordings would be unlistenable. Speaking of unlistenable, the best negative review I've ever heard was from Brian Cheney, designer of VMPS speaker systems, "I recently had a listening session in a local stately home. The sound was not good, with grain and overload that reminded me of early digital. Audiophiles would have complained. The soundstage was too big and the small instruments sounded too large. Overall quality was edgy, especially when the fortissimos came along and the room started to feedback reverberant energy. Not very satisfactory. The system: a live string quintet." Occasionally, I need to remind myself (and others) that it's not about the system, it's about the music." Evaluation CD's: - The Gladiator soundtrack System's Components
Jan's comments about his System: AA: "Jan, how would you describe your system's sound?" JH: "My system sounds as neutral and dynamic as any I've heard, and I've heard many. I enjoy going to the CES in Las Vegas every winter to hear the latest products, and found myself longing for nothing new when I got home this year." AA: "Do you think there is room for improvement?" JH: "At this point, the only way I can improve any one facet of my system is to compromise something else. Different is not necessarily better." AA: "Have you got plans for upgrading?" JH: "I have no plans to upgrade anything (but I've said that before.)" Since I wrote last, I've replaced the Accuton
ceramic drivers with two pairs of 5 1/4" Focal "W"
cones. They provide the same impact without the
resonance peak (the source of considerable listener
fatigue.) The Accutons sounded great initially,
but no matter what I did with my electronic
crossover or digital EQ, the peak could not be
eliminated. I'll never buy ceramic or metal
drivers again. I was happy with the upgrade till a professional
speaker designer dropped by. He pointed out some
muddyness in the lower midrange and less than
stellar dynamics. How could this be? I thought I had the best
drivers I could find. He said it wasn't the
drivers, but the cabinets that were producing the
problems. He demonstrated it by asking me to
squeeze the cabinets while he played some large
orchestral works. They vibrated like a chain saw.
He confirmed that spikes would make the problem
worse, and suggested cabinets modifications. As luck would have it, a friend decided to sell
his Rauna Leira speakers shortly thereafter. These
Swedish speakers are famous for their cast
concrete, transmission line cabinets. I bought and
modified them to house the Focal drivers. The
improvement wasn't dramatic till I sealed the
ports, and installed some room acoustic
treatment. Since these mods, local audiophiles are
consistently impressed with how well this system
reproduces Beethoven piano concertoes and movie
sound tracks. Everything else is much less of a
challenge. The Focals and Newform ribbons are
famous for their smooth, grain free vocals, both
male and female. Individual vocalists can be
located in choral works due to the outstanding
imaging, both width and depth. I attribute much of
that to the narrow cabinet design, speaker
placement, and the room treatments. I got rid of the giant component rack and
replaced it with a much smaller one which does not
dominate the room. It came from an exclusive shop
called K-mart, and is sold as a kitchen cart for
$50. It handles my 83 lb. amp & electronics
with aplomb. The tube amp on top of the Sherbourne is a
Dynaco ST70, a favorite with the tube crowd. Its
main attributes are that it's interesting to look
at, lights up at night, and fills the hole between
the power amp and the digital EQ, but it's no
analytical tool. |
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