What objective measurements qualify as "High Fidelity"?

[terryforsythe]

What’s the point?
Are we going to solve the problem of what people should get?
Salesmen do that.
Or is this a savour complex, or Quixotic approach to helping others?

It is like trying to get everyone to drink a Malbec because they are a good value grapes.
When some people just like Pinot or Cab.

If I was able to understand your purpose or reasoning, it would help me.

First, people often come on this forum and ask for equipment suggestions, e.g., "what amplifier should I buy." It would be nice to be able to direct them to a set of specifications they could use as a guide. There is a ranking guide for speakers that is very useful, and perhaps a list of ideal specifications for speakers could supplement that.

Second, there is no real consensus on what equipment is "high fidelity". E.g., for SNR and HD I have seen numbers ranging from 80 dB to 115 dB. That is a large range. Why not define it? When I designed RF filters, for filters designed in accordance with MIL-STD-220A there was an industry standard for "X" style filters; they had insertion loss of 100 dB min. 14 kHz - 10 GHz, both no load and full load. When companies purchased "X" style filters, they knew, or should have known, the level of performance they were getting. In audio, if somebody purchases a piece of equipment that supposedly is "high fidelity", oftentimes they have no idea of how well that equipment actually performs.

 

[Holmz]

First, people often come on this forum and ask for equipment suggestions, e.g., "what amplifier should I buy."

Probably the one with the features that they need.

It would be nice to be able to direct them to a set of specifications they could use as a guide. There is a ranking guide for speakers that is very useful, and perhaps a list of ideal specifications for speakers could supplement that.

There are already rankings for speaker and for electronics.

Second, there is no real consensus on what equipment is "high fidelity". E.g., for SNR and HD I have seen numbers ranging from 80 dB to 115 dB. That is a large range. Why not define it?

Every one says 120 is better than 100.
No one seems to agree that 90 is also as “non-hearable” as 100.
But 100 is bigger than 90. And 120 is bigger than 100.

When I designed RF filters, for filters designed in accordance with MIL-STD-220A there was an industry standard for "X" style filters; they had insertion loss of 100 dB min. 14 kHz - 10 GHz, both no load and full load. When companies purchased "X" style filters, they knew, or should have known, the level of performance they were getting.

There is no MIL STD for consumer electronics.
We don’t need a Mil-Std.
The only war was the aforementioned “Loudness war”.

In audio, if somebody purchases a piece of equipment that supposedly is "high fidelity", oftentimes they have no idea of how well that equipment actually performs.

OK it is 60 dB, because speakers are usually 40-50 dB, so the extra 10 dB is under that.

And hence, like magic, all amps are high fidelity.
It is a solved problem.

Why are we making paste and glue out of the thing?

 

[terryforsythe]

Obviously this will go nowhere.

That's fine.

 

[dlaloum]

First, people often come on this forum and ask for equipment suggestions, e.g., "what amplifier should I buy." It would be nice to be able to direct them to a set of specifications they could use as a guide. There is a ranking guide for speakers that is very useful, and perhaps a list of ideal specifications for speakers could supplement that.

Second, there is no real consensus on what equipment is "high fidelity". E.g., for SNR and HD I have seen numbers ranging from 80 dB to 115 dB. That is a large range. Why not define it? When I designed RF filters, for filters designed in accordance with MIL-STD-220A there was an industry standard for "X" style filters; they had insertion loss of 100 dB min. 14 kHz - 10 GHz, both no load and full load. When companies purchased "X" style filters, they knew, or should have known, the level of performance they were getting. In audio, if somebody purchases a piece of equipment that supposedly is "high fidelity", oftentimes they have no idea of how well that equipment actually performs.

The trouble is, it ain't that simple...

If we are talking line level equipment, we can define some base parameters, personally I strongly prefer seperate THD and S/N rather than SINAD - but based on audibility thresholds, we can set safe parameters for components that would be considered "High Fidelity" (perhaps THD of less than 60db, and S/N of more than 80db?)

Amps however are more difficult as they are reactive devices that respond to the load they are driving...
There are such things as monster amps that are well nigh universal (ie: can handle any load) - but for the most part, most people asking the question are unlikely to have the sometimes unlimited budget required for some of these...
So you end up specifying your amp for a certain load... eg: Non Reactive 8ohm Nominal speakers, with EPDR dropping down to no more than 4ohm...

Amps are (of course) well understood (solved!) technology, and within a set of load parameters, there are a plethora of options at a wide range of price points (well... for easy loads. for more difficult loads, the options tend to be more limited!)

Effectively the Amp/Speaker needs to be considered as a complete "set" (yeah powered speakers make sense!)...

But then you include the speaker... and true fidelity, and most speakers... really don't align so well!

 

[terryforsythe]

The trouble is, it ain't that simple...

It's not simple. It could be solved. But I'm realizing that far more time would be spent debating back and forth than actually making any progress. Oh well. It is what it is.

 

[Holmz]

Obviously this will go nowhere.

That's fine.

There are already reviews at the top tab.
I still don’t understand your goal, and who you are trying to save.

It's not simple. It could be solved. But I'm realizing that far more time would be spent debating back and forth than actually making any progress. Oh well. It is what it is.

What is the problem that needs to be solved?

One goes into some shop, or finds something on line.
It is unclear whether Amp-A will work with Speaker-B unless someone knows and has tried it.
You go into a shop and they tell you, Amp-A and Speaker-B work together.

I can somewhat see that on the speaker specs, if the speaker is a behaved load.
But… there is no place in the specs whether the speaker load is rated… on a graph… comparing it across many other speakers.

If we have 100 amplifiers and 100 speakers, then maybe 80-90% of the 10k combos would work together, but the other 1-2k take some chin scratching.

it is not a simple case pick speaker-B and pick amplifier-A independently.
(Most will be fine, but not all of them.)

 

[terryforsythe]

What is the problem that needs to be solved?

It's puzzling to me why you even got involved in the first place.

You started with a suggestion to add to the specifications, which I thought sounded promising. I then I asked for more detail on what you proposed, and your tone changed entirely. Rather than actually contributing anything of value, you merely philosophize. I assumed you had expertise in the type of specification you suggested, but perhaps I was wrong, I don't know.

Initially I thought this could be a fun thread in which to participate, get different perspectives, work together, etc. Nonetheless, it is clear that too many people in this thread are way more interested in arguing, nitpicking and pontificating, and not enough people are actually contributing anything of value for a specification. If that is what brings them joy, great, have at it. But I'm over it.

Good luck everyone.

 

[Sal1950]

The engineering of electronics may be solved, but not all electronics manufacturers properly implement those solutions.

Very true, but that's not the big problem in this industry.
For decades the engineers worked their as-ses off to bring us out of the dark ages of the Edison dictaphone.
Now that we're come so far. the leading enthusiast media don't give a rodents behind. Over at places like Stereophile, John Atkinson can measure a piece of gear that by 2023 standards is broken, but in the end toss the ball to some 80yo deaf reviewer who will type 10 pages of glowing prose talking about veils removed, warmth and all the rest of that BS.
The Hi Fi industry is controlled by a bunch of $ worshiping whores that care little about obtaining real incredible performance, only how much they can fleece from a gullible public.

 

[Holmz]

It's puzzling to me why you even got involved in the first place.

You started with a suggestion to add to the specifications, which I thought sounded promising. I then I asked for more detail on what you proposed, and your tone changed entirely. Rather than actually contributing anything of value, you merely philosophize. I assumed you had expertise in the type of specification you suggested, but perhaps I was wrong, I don't know.

Enough expertise that I know that transient response can be important, and is a way to describe how transients are handled/presented.
it is just factual that any time domain, or transient response, is a distant 3rd or 4th (at best) in what people/reviewers usually list as important to consider.

Initially I thought this could be a fun thread in which to participate, get different perspectives, work together, etc.

yeah, no.
Everyone ranks… in some order, what is important.
So with say 3 different metrics, you have 6 distinct camps. (ABC, ACB, BAC, BCA, CAB, CBA.)
And that just increases with 4, 5, 6, metrics.
Everyone ranks and rates what is important differently.

I have given you at least 1 more thing to consider, so I guess my job is done.

Nonetheless, it is clear that too many people in this thread are way more interested in arguing, nitpicking and pontificating, and not enough people are actually contributing anything of value for a specification. If that is what brings them joy, great, have at it. But I'm over it.

I am not sure that it is unreasonable for me to ask, “what is the purpose”.
it seems like it is a Quixotic endeavour to try and make recommendations for “the masses”, when there is so much that feeds into what people like to buy.
We have totally discounted psychology, etc.

Since there are a huge amount of speakers sold, which vary wildly in design, it appears like it would take a lifetime of research to capture why people get what they get.
Certainly enough work to keep Toole, Olive, and dozens of others employed.

And we want to boil that down all that research and work, into some recommendation list to help people?

Good luck everyone.

Likewise.

 

[Madlop26]

"What objective measurement qualifies as High Fidelity"
Sorry guys, I am afraid this discussion is futile, there is no way any particular person in this forum or in the world in that regard, can answer this question. That is because of the lack of standardizations. Simple as that.
the problem is actually relatively simple. The main issue is the lack of resources. if this were a medical issue (area where I come from) standardizations and definitions would come out in weeks. First , They would form a task force of people with the most expertise in the area, they will get together for days until they have a reasonable definition of what "High Fidelity" is. They would come with something like this: "High Fidelity is when 95% of blind test subjects cannot differentiate a live instrument from a recorded one"
Then the research of what objective measure can differentiate high fidelity from no-high fidelity is only one step further.

 

[Killingbeans]

They would come with something like this: "High Fidelity is when 95% of blind test subjects cannot differentiate a live instrument from a recorded one"

It would need to be quite a bit more fleshed out.

If you record a single instrument in an anechoic chamber (or just a sufficiently "dead" room) and play the recording back through a mono speaker that has a smooth radiation pattern similar to the the one of the instrument, it will probably be pretty easy for the setup to pass that test.

Some instruments would be a far greater challenge than others in terms of low bass and SPL, but the party tricks of simulating a single instrument or a singing voice is not that difficult to pull off.

The real problem is the illusion of a room/space. The recording contains information about a room. Either a real one captured by a number of microphones, or one fabricated in the studio. And when you play it back, it "mixes" with your listening space. The human brain is pretty good a filtering out most of that interference, but you can't avoid it completely. Luckily most people seem to enjoy the way that some of the room interactions "expand" the experience.

The most helpful way of defining "High Fidelity" would probably be to find a speaker radiation pattern that gives the most optimal compromise between "disappearing" and adding "enjoyable taint" when interacting with a typical living space.

Honestly, the most no-nonsense way of achieving something as close to the fabled perfect illusion as you can get, is probably by investing in a big Atmos setup.

But people would much rather spend time on hunting imaginary distortion and noise floor gremlins in their DACs, or rave about how their turntables break the laws of physics when the planets align in a certain way. Solving real problems effectively is sacrilege

 

[Roland68]

Somewhere we can probably find the old European DIN standards for audio/hifi, which I dimly recall was an attempt to codify such things decades ago. They are probably still just about sufficient, as those who heard decent systems in the 1970s can probably attest. In fact, slightly scarily, some now classic designs such as the Quad Electrostatic, can still give a remarkably persuasive sound, despite some fairly glaring weaknesses under measurement. The ears’s and brain’s ability to ’fill in the gaps’ is probably what makes even table radios and car audio enjoyable, even if they are far from ‘Hifi’.

A bit of googling suggests DIN 45500 isn’t easily accessible. However, some excerpts include this:-

”The document outlines the technical requirements for HiFi standard DIN 45500 for low frequency amplifiers from 1977, including: 1) The transmission range must be between 40-16,000 Hz with permissible deviations of ±1.5 dB for linear inputs and ±2 dB for equalizing inputs. 2) Transmission measure differences between stereo channels must be less than 3 dB without balance adjustment and less than 6 dB with a balance adjustment over 8 dB. 3) Distortion must be less than 1% from 40-12,500 Hz for integrated amplifiers.”

Modest indeed! But it does approximate to the specs in your opening post.

High Fidelity was introduced in 1934 and expanded the bandwidth at that time to 30 to 8,000 Hz. DIN 45500 followed in the 1960s with various extensions and DIN 45511 for study equipment. The following EN 61305 actually has nothing to do with it.

The fact that the Nyquist-Shannon sampling theorem, which, among other things, is the basis of CD players and today's digital technology in the audio sector, was introduced in 1933, a year before High Fidelity, is certainly just a coincidence.

So, to be clear, we are discussing a 90-year-old term...
Speakers with permanent magnets didn't come along until 2 years later.

As the saying goes, when your horse is dead, dismount.