What's Wrong with the Hi-Fi Scene?: A 700$ NAD Integrated Amp Is Indiscernible from a +20.000$ Mark Levinson Preamp & Dual Monaural Power Amplifier
Apr 23, 2018 at 12:07 PM Post #32 of 77
Anyway, the subject of whether a high end amp sounds better than "ordinary" amps wad, or should have been, settled in the 1980s.
https://en.wikipedia.org/wiki/Bob_Carver

I hadn't heard of that. Let's see:

Amplifier modeling
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 he’d 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 “t” stood for transfer function modified).

In 1985, Stereophile magazine challenged Bob to copy a Conrad-Johnson Premier Four (the make and model was not named then, but revealed later) amplifier at their offices in New Mexico within 48 hours. The Conrad Johnson amplifiers were one of the most highly regarded amplifiers of the day, costing in excess of $6,000 a pair.

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, (null difference testing consists of driving two different amplifiers with identical signal sources and exact levels, but out of phase by exactly 180 degrees. If the amplifiers were 100% identical, no sound would be heard. If sound was heard, the audio amps had different properties). Bob Carver used "distortion pots" to introduce amplifier characteristics, fine-tuned to null-out any sound differences. His "motel-room" modified amplifier sound was so similar, Stereophile Magazine editors could not tell the difference between his amplifier and one costing more than $6,000. This amplifier was marketed as the M1.0t for about $400.00. Bob Carver may have single-handedly debunked any number of theories about sound quality by using physics, blind and double-blind testing and unbiased measurements (such as "gold-plated speaker wires sound better than copper wires", etc.). Carver 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.


wow :frowning:


As I understand this, money should be spent, mostly, on speakers, right?
 
Apr 23, 2018 at 12:41 PM Post #33 of 77
yes
 
Apr 23, 2018 at 3:11 PM Post #35 of 77
once everything is great, the transducers are always going to be the weak link in the playback chain(with the room if speakers). this is a fact based on how they are consistently the lowest resolution device, so they're also where the most significant changes can be expected from gear to gear.
 
Apr 23, 2018 at 7:11 PM Post #36 of 77
I hadn't heard of that. Let's see:

Amplifier modeling
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 he’d 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 “t” stood for transfer function modified).

In 1985, Stereophile magazine challenged Bob to copy a Conrad-Johnson Premier Four (the make and model was not named then, but revealed later) amplifier at their offices in New Mexico within 48 hours. The Conrad Johnson amplifiers were one of the most highly regarded amplifiers of the day, costing in excess of $6,000 a pair.

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, (null difference testing consists of driving two different amplifiers with identical signal sources and exact levels, but out of phase by exactly 180 degrees. If the amplifiers were 100% identical, no sound would be heard. If sound was heard, the audio amps had different properties). Bob Carver used "distortion pots" to introduce amplifier characteristics, fine-tuned to null-out any sound differences. His "motel-room" modified amplifier sound was so similar, Stereophile Magazine editors could not tell the difference between his amplifier and one costing more than $6,000. This amplifier was marketed as the M1.0t for about $400.00. Bob Carver may have single-handedly debunked any number of theories about sound quality by using physics, blind and double-blind testing and unbiased measurements (such as "gold-plated speaker wires sound better than copper wires", etc.). Carver 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.


wow :frowning:


As I understand this, money should be spent, mostly, on speakers, right?
Amusingly Mr carver has been selling very nice and vey expensive tube amps for years.....some very innovative speakers also...great designer....and a great showman .Love this guy!
 
Last edited:
Apr 23, 2018 at 7:29 PM Post #37 of 77
Last time I checked Sunfire, he had amps with built in DSP tube sound- solid state, not tubes.
 
Apr 23, 2018 at 8:14 PM Post #40 of 77
I hadn't heard of that. Let's see:

Amplifier modeling
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 he’d 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 “t” stood for transfer function modified).

In 1985, Stereophile magazine challenged Bob to copy a Conrad-Johnson Premier Four (the make and model was not named then, but revealed later) amplifier at their offices in New Mexico within 48 hours. The Conrad Johnson amplifiers were one of the most highly regarded amplifiers of the day, costing in excess of $6,000 a pair.

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, (null difference testing consists of driving two different amplifiers with identical signal sources and exact levels, but out of phase by exactly 180 degrees. If the amplifiers were 100% identical, no sound would be heard. If sound was heard, the audio amps had different properties). Bob Carver used "distortion pots" to introduce amplifier characteristics, fine-tuned to null-out any sound differences. His "motel-room" modified amplifier sound was so similar, Stereophile Magazine editors could not tell the difference between his amplifier and one costing more than $6,000. This amplifier was marketed as the M1.0t for about $400.00. Bob Carver may have single-handedly debunked any number of theories about sound quality by using physics, blind and double-blind testing and unbiased measurements (such as "gold-plated speaker wires sound better than copper wires", etc.). Carver 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.


wow :frowning:


As I understand this, money should be spent, mostly, on speakers, right?
Using wiki is dangerous anybody can post anything....Carver added a resistor or 2 changing transfer function or impedance....no distortion is mentioned in the original article.By the way Bob Carver sells some very expensive tube amps himself....wont take a lot of googling to find him telling you how good tube amps are.....the carver challlenge is not what the wiki page makes it out to be.
 
Last edited:
Apr 23, 2018 at 9:09 PM Post #41 of 77
I hadn't heard of that. Let's see:

Amplifier modeling
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 he’d 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 “t” stood for transfer function modified).

In 1985, Stereophile magazine challenged Bob to copy a Conrad-Johnson Premier Four (the make and model was not named then, but revealed later) amplifier at their offices in New Mexico within 48 hours. The Conrad Johnson amplifiers were one of the most highly regarded amplifiers of the day, costing in excess of $6,000 a pair.

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, (null difference testing consists of driving two different amplifiers with identical signal sources and exact levels, but out of phase by exactly 180 degrees. If the amplifiers were 100% identical, no sound would be heard. If sound was heard, the audio amps had different properties). Bob Carver used "distortion pots" to introduce amplifier characteristics, fine-tuned to null-out any sound differences. His "motel-room" modified amplifier sound was so similar, Stereophile Magazine editors could not tell the difference between his amplifier and one costing more than $6,000. This amplifier was marketed as the M1.0t for about $400.00. Bob Carver may have single-handedly debunked any number of theories about sound quality by using physics, blind and double-blind testing and unbiased measurements (such as "gold-plated speaker wires sound better than copper wires", etc.). Carver 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.


wow :frowning:


As I understand this, money should be spent, mostly, on speakers, right?
Carver also went on to sell the clone amplifier in production quit successfully.
 
Apr 24, 2018 at 12:59 AM Post #42 of 77
This is more of a curiousity of mine, because it won't directly impact my life or wallet, but I've always wondered where the line is on this subject.

I'm a fan of blind testing, so I readily accept that a $700 amp is inaudibly different from a $20,000 amp, but I don't think this trend over inaudible differences carries down to the ultra low-end.

More specifically, I know that if I plug a sensitive IEM into my HP laptop's headphone jack, the IEM will hiss/produce static when there is no audio playing, however this does not happen when I plug the same IEM into my $100 usb dac/amp (sabaj Da3).

Laptop makers are understandably much more focused on things such as CPUs and memory when they make specifications sheets, so I don't have any noise statistics for the headphone jack to provide. I guess this is a complicated way of stating I'm curious what the threshold of audibility is.
 
Apr 24, 2018 at 1:26 AM Post #43 of 77
Impedance issues don't mean that there's anything wrong with the amp. It just means you're using the wrong headphones for that particular player or amp.
 
Apr 24, 2018 at 5:14 AM Post #44 of 77
once everything is great, the transducers are always going to be the weak link in the playback chain(with the room if speakers). this is a fact based on how they are consistently the lowest resolution device, so they're also where the most significant changes can be expected from gear to gear.
Which of course is one of the reasons analog recording or playback equipment relying on mechanical movement and transducers do scale with price (to a certain extent), unlike digital equipment.

For example, generally you can hear a difference between a $200 turntable and $5000, but a difference between the same price points of a DAC is all in one's head. Unless the expensive DAC has been intentionally designed to be euphonic so therefore not musically transparent.
 
Apr 24, 2018 at 5:18 AM Post #45 of 77
This is more of a curiousity of mine, because it won't directly impact my life or wallet, but I've always wondered where the line is on this subject.

I'm a fan of blind testing, so I readily accept that a $700 amp is inaudibly different from a $20,000 amp, but I don't think this trend over inaudible differences carries down to the ultra low-end.

More specifically, I know that if I plug a sensitive IEM into my HP laptop's headphone jack, the IEM will hiss/produce static when there is no audio playing, however this does not happen when I plug the same IEM into my $100 usb dac/amp (sabaj Da3).

Laptop makers are understandably much more focused on things such as CPUs and memory when they make specifications sheets, so I don't have any noise statistics for the headphone jack to provide. I guess this is a complicated way of stating I'm curious what the threshold of audibility is.

That is not necessarily so. Many high end amps are not musically transparent. They are intentionally designed to be subjectively euphonic so as to acheive a "signature sound" for product differentiation and for appeal to less sophisticated audiophiles that have money to burn. There is nothing intrinsically wrong with preferring a sound which is more euphonic to that individual (remebering that it is all subjective) but having the amplifier do it is a blunt, costly and inefficent way to do it. Better off using a parametric equaliser in the playback chain.
 

Users who are viewing this thread

Back
Top