--- In FairfieldLife@yahoogroups.com, "Xenophaneros Anartaxius" <anartaxius@...> wrote: > > --- In FairfieldLife@yahoogroups.com, "Alex Stanley" <j_alexander_stanley@> > wrote: > > > --- In FairfieldLife@yahoogroups.com, "Xenophaneros Anartaxius" > > <anartaxius@> wrote: > > > > > > --- In FairfieldLife@yahoogroups.com, "Richard J. Williams" <richard@> > > > wrote: > > > > > > > The Yamaha basic amplifier puts out 250 watts per channel in > > > > stereo with less than .00001% total harmonic distortion. With that > > > > kind of power I need some really robust speakers, so I moved up > > > > from Advents to floor-standing JBLs. > > > > > > > What is interesting about this is that not many people can > > > distinguish less than 1% total harmonic distortion on pure tones, > > > let alone music, and few speaker systems can get as low a 0.5% > > > total harmonic distortion; most have higher distortion, with car > > > stereos running as high as 5%. Thus an amplifier with even 0.1% > > > harmonic distortion typically could not be heard as different from > > > any amplifier with less distortion through any speaker system, all > > > else being equal (frequency response, level etc.). > > > > > > > Back in the mid-80s, I got suckered by Carver's hyped specs, and the local > > hi-fi dealer in Fairfield did a great job of clueing me in by simply > > putting my hugely powerful Carver amp up against a 60 watt Adcom on the > > same set of speakers. Whodathunk playing loud is not the same as playing > > well? It was shocking how shitty the Carver amp sounded compared to the > > Adcom. > > > It is hard to say just what causes a specific difference in sound. From the > viewpoint of double-blind testing a trained person can detect a 0.2dB > difference in sound level, though most people can't detect a 1 or 2dB > difference. A louder level usually sounds 'better' to the person, even if > they cannot tell the volume level is different, it's a subliminal resonse. > This is a trick audio dealers use to differentiate speakers - play the more > expensive one a bit louder. This also applies to portions of the frequency > response. A slight rise at 4 kilohertz will make equipment sound a bit > brighter. The big difference in speakers is uneven frequency response. If the > entire range of the frequency response can be held within 0.2db, and the > levels overall within that range, they should sound the same; outside that > range, just a bit, some persons may detect a difference. This can be done > with amplifiers, but the best speakers' frequency response is rarely within > plus or minus 2dB, so they all sound different in some way depending on where > the peaks and valleys of the response fall, in the bass, mid-range, or treble. > > It is very difficult to control these levels to these tolerances outside of a > laboratory setting. Carver was a very clever engineer, so I wonder what the > problem was with the amp you had. The high fi dealer you dealt with, that > wasn't Paul Squillo was it? He used to pull the volume control trick when > demonstrating speakers. > > A note about Carver from the Wikipedia: > > Carver caused a stir in the industry in the mid-1980s when he challenged two > high-end audio magazines to give him any audio amplifier at any price, and > heâd duplicate its sound in one of his lower cost (and usually much more > powerful) designs. Two magazines accepted the challenge. > > First, The Audio Critic chose a Mark Levinson ML-2 which Bob acoustically > copied (transfer function duplication) and sold as his M1.5t amplifier (the > âtâ stood for transfer function modified). > > In 1985, Stereophile magazine challenged Bob to copy a Conrad-Johnson Premier > Five (the make and model was not named then, but revealed later) amplifier at > their offices in New Mexico within 48 hours. The Conrad Johnson amplifier was > one of the most highly regarded amplifiers of its day, costing in excess of > $12,000. > > Of note that in both cases, the challenging amplifier could only be treated > as a "black box" and could not even have its lid removed. Nevertheless, > Carver, using null difference testing, successfully copied the sound of the > target amplifier and won the challenge. The Stereophile employees failed to > pass a single blind test with their own equipment in their own listening > room. He marketed "t" versions of his amplifiers incorporating the sound of > the Mark Levinson and Conrad Johnson designs which caused him some criticism > by those who failed to understand the true nature of the challenge â" that > it was possible to duplicate an audio amplifier's sound in two completely > dissimilar designs. In light of this criticism, Carver went on to design the > Silver Seven, the most expensive and esoteric conventional amplifier up to > that time and duplicated its sound in his M 4.0t and later models which sold > for some 1/40th the price (around $600â"$1500).
Cool. I had the pleasure of hearing the Mark Levinson reference set-up at a Hi-Fi show once. It sounded considerably better than reality ever could, to my ears anyway. The power amps cost $30,000 a pair at the time, I would love a copy with the same sound for (a lot) less! The whole system cost about $100,000 and required your house to be rewired to provide enough current, not for volume but for the control it applied to speakers. Great fun but the company stopped making them as each power amp took about two weeks to build so they weren't particularly cost effective. They sold a lot more of them than you'd expect at the price though. Hardly surprising considering the sound, I have heard all the most expensive stuff and thought the MLR much superior to all the Krells and Boulders at even twice the price. Every other Hi-Fi sounds like it's just pretending to be music, the ML's sounded like the real thing but improved. I should work for their sales team....
