Can you hear a difference in Sound between Audio Amplifiers?

[jinjuku]

Is echoic memory referring to comparing sounds adjacent in time

WIKI for the win:

Echoic memory is one of the sensory memory registers; a component of sensory memory (SM) that is specific to retaining auditory information. The sensory memory for sounds that people have just perceived is the form of echoic memory.[SUP][1][/SUP] Unlike visual memory, in which our eyes can scan the stimuli over and over, the auditory stimuli cannot be scanned over and over. Overall, echoic memories are stored for slightly longer periods of time than iconic memories (visual memories).[SUP][2][/SUP] Auditory stimuli is received by the ear one at a time before it can be processed and understood. For instance, hearing the radio is very different from reading a magazine. A person can only hear the radio once at a given time, while the magazine can be read over and over again. It can be said that the echoic memory is like a "holding tank" concept, because a sound is unprocessed (or held back) until the following sound is heard, then only can it be made meaningful.[SUP][3][/SUP]This particular sensory store is capable of storing large amounts of auditory information that is only retained for a short period of time (3–4 seconds). This echoic sound resonates in the mind and is replayed for this brief amount of time shortly after the presentation of auditory stimuli.[SUP][4][/SUP] Echoic memory encrypts only moderately primitive aspects of the stimuli, for example pitch, which specifies localization to the non association brain regions.[SUP][5][/SUP]

 

[Steve81]

I really do wonder if there is a borderline condition for amplifiers that could cause preferences.

There certainly can be, but then you'd probably start falling into the categories of "overdriving the amplifier" and "mating an amplifier to a load for which it is ill suited". Of course, those factors complicate things considerably IMO. A little while back I posted an example of a Pioneer receiver whose measured FR profile changed significantly when switching from an 8 ohm test load to a 4 ohm load. Unless you happen to be aware of that specific measurement, you'd not really expect such an anomaly from a Pioneer receiver costing in excess of $2000. I can only imagine what would happen if you mated that receiver to something like the ML Montis which stays under 4 ohms from 4kHz on up, and under 2 ohms in the top octave.

 

[Steve81]

With amps we are also dealing with THD+noise of 0.00 something such as Bryston's and 0.0 something for many receivers, both can be considered negligible too

Of course I would note that some amplifiers may exhibit much worse performance, depending on the conditions/power levels.

Will 0.3% THD+N at 1W be audible? I couldn't say; but it's certainly not a Bryston grade measurement.

 

[AcuDefTechGuy]

Who's telling people to be unhappy with their things? May be I missed a post or 2, I'll have another look.

He took issue with me saying I don't care if someone is happy with imaginary improvements. I'm saying I wont tell someone not to like their system, imaginarily good or actually so.

Whether we all agree or not on any subjects, I am 100% for everyone to be 100% happy with their things. This is a hobby.

 

[AcuDefTechGuy]

People make outrageous claims about superhuman hearing, and then they expect everyone to just accept their word for it.

What we have here....is a failure to communicate.

 

[Irvrobinson]

There certainly can be, but then you'd probably start falling into the categories of "overdriving the amplifier" and "mating an amplifier to a load for which it is ill suited". Of course, those factors complicate things considerably IMO. A little while back I posted an example of a Pioneer receiver whose measured FR profile changed significantly when switching from an 8 ohm test load to a 4 ohm load. Unless you happen to be aware of that specific measurement, you'd not really expect such an anomaly from a Pioneer receiver costing in excess of $2000. I can only imagine what would happen if you mated that receiver to something like the ML Montis which stays under 4 ohms from 4kHz on up, and under 2 ohms in the top octave.

Overloading an amp, clipping, or just a weak design is too easy. When I tested my ATI AT602 on the Salon2s I could hear where the anti-clipping circuit limited and compressed output, and I'm sure I could pick it out every time in a blinded trial on some selected material. Admittedly the sound level was higher than I usually listen at, but not unreasonably so. I think you know that I'm referring to the conscious or subconscious audibility of distortion or noise, or some other sort of "normal" behavior of an amplifier.

 

[Irvrobinson]

Of course I would note that some amplifiers may exhibit much worse performance, depending on the conditions/power levels.

Will 0.3% THD+N at 1W be audible? I couldn't say; but it's certainly not a Bryston grade measurement.

I can't say either, but I'd be annoyed if I had spent good money on a product with such inferior performance. Interesting how on Amazon that AVR got such a high number of 3-star and below reviews, which is quite unusual. Perhaps one can forecast overall product satisfaction with AVRs by just measuring distortion at 4 ohms. Yes, I'm joking...

 

[RichB]

Overloading an amp, clipping, or just a weak design is too easy. When I tested my ATI AT602 on the Salon2s I could hear where the anti-clipping circuit limited and compressed output, and I'm sure I could pick it out every time in a blinded trial on some selected material. Admittedly the sound level was higher than I usually listen at, but not unreasonably so. I think you know that I'm referring to the conscious or subconscious audibility of distortion or noise, or some other sort of "normal" behavior of an amplifier.

I have on occasion put music on while working at my computer without really paying close attention and then felt something was wrong. I found that I had left the conversion settings in J River when streaming to the Oppo BDP-105 USB DAC.

Just an observation.

- Rich

 

[3db]

WIKI for the win:

Echoic memory is one of the sensory memory registers; a component of sensory memory (SM) that is specific to retaining auditory information. The sensory memory for sounds that people have just perceived is the form of echoic memory.[SUP][1][/SUP] Unlike visual memory, in which our eyes can scan the stimuli over and over, the auditory stimuli cannot be scanned over and over. Overall, echoic memories are stored for slightly longer periods of time than iconic memories (visual memories).[SUP][2][/SUP] Auditory stimuli is received by the ear one at a time before it can be processed and understood. For instance, hearing the radio is very different from reading a magazine. A person can only hear the radio once at a given time, while the magazine can be read over and over again. It can be said that the echoic memory is like a "holding tank" concept, because a sound is unprocessed (or held back) until the following sound is heard, then only can it be made meaningful.[SUP][3][/SUP]This particular sensory store is capable of storing large amounts of auditory information that is only retained for a short period of time (3–4 seconds). This echoic sound resonates in the mind and is replayed for this brief amount of time shortly after the presentation of auditory stimuli.[SUP][4][/SUP] Echoic memory encrypts only moderately primitive aspects of the stimuli, for example pitch, which specifies localization to the non association brain regions.[SUP][5][/SUP]

Claims based on long term listening tests should be dismissed or viewed with a subjective preference other than sound according to the info supplied above. So..now that we narrowed it down that long term tests are far from accurate, we now have to go back to SBT with instantaneous switching between units under test to hear differences.

 

[Steve81]

I think you know that I'm referring to the conscious or subconscious audibility of distortion or noise, or some other sort of "normal" behavior of an amplifier.

I understand your position; I'm largely just trying to bridge the gap.

In the case of the Onkyo there, I wouldn't call it a bottom feeder/extraordinarily poor design, nor would I really qualify it as being overloaded at 1W into a 4 ohm resistive load. Of course, if someone wanted to get overly picky, they could state that the measurement is evidence that it really isn't designed for a 4 ohm load. Personally, I'd consider it a good "borderline" case where someone may be able to ascertain some difference between it and a Bryston.

 

[DD66000]

And, no, I'm not arguing just for the point of argument, I really do wonder if there is a borderline condition for amplifiers that could cause preferences.

One situation that is real is ear fatigue. We know there are speakers that are laid back and speakers that are forward, especially on the HF.
If one pairs a forward speaker with an amp that is also forward, the result will be ear fatigue in about 10 minutes.
And once ear fatigue sets in, you do not have to even think if its real, the pain is there.
Replace that amp with one that is smoother on the HF and the ear fatigue goes away.
I'll give an example; JBL/Yamaha combo tends to be a bit fatiguing. Change to a HK, Marantz, Parasound and there will be no fatigue.
I know that from personal experience.

 

[Gordonj]

Whether we all agree or not on any subjects, I am 100% for everyone to be 100% happy with their things. This is a hobby.

100% right on! While the passion is amazing for this hobby, and we all will have our opinions that we feel are right, i think i would more worry about the speakers we are using or the DAC's that we are running our sources through. Those two items can impact a sound so much more then a subtle possible change in an amp.

 

[M Code]

I understand your position; I'm largely just trying to bridge the gap.

In the case of the Onkyo there, I wouldn't call it a bottom feeder/extraordinarily poor design, nor would I really qualify it as being overloaded at 1W into a 4 ohm resistive load. Of course, if someone wanted to get overly picky, they could state that the measurement is evidence that it really isn't designed for a 4 ohm load. Personally, I'd consider it a good "borderline" case where someone may be able to ascertain some difference between it and a Bryston.

The 605 was an entry-level AVR, products in that segment are designed for price and 8 Ohms performance not 4 Ohms..
The THD spec into 8 Ohms is roughly 50% of the 4 Ohm measurement...

Just my $0.02...

 

[Steve81]

The 605 was an entry-level AVR

Depends on your definition of entry level I suppose. At an MSRP of $599, it isn't exactly at the bottom of the totem pole.

products in that segment are designed for price and 8 Ohms performance not 4 Ohms..

They're designed to drive 8 ohm nominal speakers to be sure, but if a $600 AVR can't deliver 1W cleanly into a 4 ohm resistive load, that's pretty sad any way you dice it.

 

[AcuDefTechGuy]

100% right on! While the passion is amazing for this hobby, and we all will have our opinions that we feel are right, i think i would more worry about the speakers we are using or the DAC's that we are running our sources through. Those two items can impact a sound so much more then a subtle possible change in an amp.

I wonder what would happen if we all agreed on everything ?

Would there be anything to talk about?

 

[Irvrobinson]

Claims based on long term listening tests should be dismissed or viewed with a subjective preference other than sound according to the info supplied above. So..now that we narrowed it down that long term tests are far from accurate, we now have to go back to SBT with instantaneous switching between units under test to hear differences.

I'm not buying that. If the tests are blind and reveal a positive correlation they should be valid. There's more to preference than short-term auditory memory.

 

[mtrycrafts]

I only brought up the Davis paper because you wrote The problem is that cables measure exactly alike, and didn't know how to read that.
Maybe I should have filtered your writing more in my reply.

 

[3db]

I'm not buying that. If the tests are blind and reveal a positive correlation they should be valid. There's more to preference than short-term auditory memory.

You misread my post. Please reread again. Are you referring to listener fatigue? Floyd Toole pointed out through studies that indicate long auditory memory is in accurate. Do you know something he doesn't?

 

[mtrycrafts]

... Do you think a cable has an SNR above thermal noise? ...

Interesting that you brought this up
I remember some others on another board argued that in fact it was above the noise and even Jneutron tried to convince them otherwise to no avail.

 

[Irvrobinson]

Please reread my post. You totally missed my point.

I did? Well, I must be dense, because I just reread it and it doesn't feel like I missed your point. Can you elaborate more for the mentally challenged?