Frequency response is everything!?...

[treitz3]

"Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not". - Nelson Pass

Tom

 

[schlager]

Thanks Ron, well it sounds natural, balanced, realistic and dynamic. I find it hard to describe sound in comprehensive way, but my reference is acoustic live music, I play music myself. Beside frequency response I find the dynamic abilities very important, so I have high efficient 4 way active Synergy horns with controlled directivity, they are pretty special speakers, nothing is like them. They function as a giant full range driver with all sound from 100 hz and up, coming from the same place in space and time. To support that I have 4000 liter front loaded bass horns. The room is well treated with absorbers and some diffusion in the back of the room. Front end is standard gear, nothing special, DIY cables, it's just doing it's thing, getting out of the way, to let the speakers sing.

 

[schlager]

Yup, Mike. Cyclic activity. I guess we have to put up with the latest cycle, then they will fade once again and we can move on. It is what it is.

Tom

Wow, that is really condescending, no need for that, pls.

 

[treitz3]

Take it however you will. Some folks have been around the block a time or two.

Tom

 

[Gregadd]

Ok, so here's an example of a speaker review on ASR (Magnepan LRS Speaker Review). Tons of measurement data there, but you can see that listening tests were also done before the author reached his conclusions.

Regarding your hypothetical where someone only measures and someone only listens, it's hard to say. I'm skeptical of sighted listening tests because of the problem of expectation bias. If the device under test was something simple like a cable, I would definitely preference the measurement-only folks. If the DUT was a speaker and the listen-only group was blinded, I would be inclined to trust their conclusions over what the measurement folks had to say.

Really. AMIR is your example of measurement neutrality?

 

[Ron Resnick]

Thanks Ron, well it sounds natural, balanced, realistic and dynamic. I find it hard to describe sound in comprehensive way, but my reference is acoustic live music, I play music myself. Beside frequency response I find the dynamic abilities very important, so I have high efficient 4 way active Synergy horns with controlled directivity, they are pretty special speakers, nothing is like them. They function as a giant full range driver with all sound from 100 hz and up, coming from the same place in space and time. To support that I have 4000 liter front loaded bass horns. The room is well treated with absorbers and some diffusion in the back of the room. Front end is standard gear, nothing special, DIY cables, it's just doing it's thing, getting out of the way, to let the speakers sing.
View attachment 106410

What are the round things covered by wood in the front? Are those the base horns?

Is there any parametric equalizer anywhere in the system? is there any DSP anywhere in the system?

 

[henrich3]

Really. AMIR is your example of measurement neutrality?

Not sure what you mean by that. Do you have reason to believe that his measurements aren't trustworthy? For example, did any of the measurements in that Magnepan speaker review that I linked look wrong to you?

 

[Gregadd]

Not sure what you mean by that. Do you have reason to believe that his measurements aren't trustworthy? For example, did any of the measurements in that Magnepan speaker review that I linked look wrong to you?

I am not qualified to comment on the accuracy of his measurements. I am however very familiar with his approach to the evaluation of audio equipment. To say he is biased toward measurements is putting it lightly.it

 

[pjwd]

Since it is very rare that we actually see any in-room measurements from peoples systems, please let me introduce you to mine. Just to be clear I find frequency response the most important, as sound is actually comprised of ....drum roll... frequency and time.

FR

View attachment 106407

IR
View attachment 106408

Step response

View attachment 106409

Pretty good indeed !
Are you using a acourate or similar as a crossover.
Is the reflection at just under 2ms a floor reflection
Cheers
Phil

 

[henrich3]

I am not qualified to comment on the accuracy of his measurements. I am however very familiar with his approach to the evaluation of audio equipment. To say he is biased toward measurements is putting it lightly.it

I agree with you that he's biased towards measurements, but he also does subjective listening tests in his reviews. Do you believe that his "measurement bias" makes his conclusions less credible? In my mind his extensive measurements give more weight & credibility to his subjective conclusions.

 

[MaxwellsEq]

At the very least, consistent, repeatable measurements let you know if something is faulty.

I've fixed a lot of professional recording and domestic electronics. Once repaired, I had to check that the device was safe(!) and working properly. To do so I needed to measure (at least) noise, frequency response, channel separation and distortion. I'd also use an oscilloscope to check nothing weird was going on outside of the audio band. I also soak test it.

There are audio products sold which don't measure very well when new and working normally. As an electronic engineer, I simply couldn't bring myself to buy them, regardless of how well the audio community rated them.

 

[RCanelas]

Going back to the start of the thread.

The argument that a frequency response or power response is enough to characterize a sound system is profoundly representative of the state to which some people get, that, while not having been trained in or correctly exposed to the fundamentals of science and epistemology, believe that a sliver of tech information is enough to place them ahead and have a discussion in an ambiguous field with confidence. Confusing information with knowledge is a capital sin in my neighborhood. Fortunately I don't see many people that adept in this way of thinking here. Alas the same can be said the other way around. Just because you have an experience that doesn't map well to any measure or model that you know of, doesn't mean it doesn't exist, that it is unknowable or a branch of black magic. Everything we do here in audio is absurdly simple comparing to even the most trivial tech driven activities today (almost everything involving a microprocessor, making a phone call, checking you mail, driving your car, getting on a plane or making a movie), even taking into account the interaction with our individual auditory and cognitive systems. It is not a trivial problem, but not in the proximity of the list of hard problems we solve everyday as a collective. There are reasons we don't take it seriously tough, that justify the absence of such hard results for audio reproduction, namely the lack of interest and consequently funding. What we know seems to be enough to produce value.

'FR is enough to characterize an audio system'. I always find it useful to apply a bit of reductio ad absurdum to clearly delineate the boundaries of the arguments being put forth, and in this case, it is easy.
- if I play you the same track but backwards, you'll get the same cumulative frequency response. It is an integral, has no topological meaning. I can chop a track in 5 second intervals and introduce 1 sec silence in between. Same FR at the end.
- I do audiograms from time to time. It is pretty clear to me that my hearing is a) not linear and b) not the same sensitivity across the spectrum as anyone else. Yet, apart from crossing clinical thresholds, we all hear what we need to hear, just fine. So either a) our hearing system is able to compensate (within reason) to these variations or b) it is not very relevant (again, within reason)
- a simple FR measurement (that usually is what gets passed to a consumer) doesn't distinguish signal from any type of distortion, it condensates everything into linear distortion. This is not even close to being representative of how our hearing works. I can give you a loudspeaker with insane levels of high order distortion for example, DSP the hell out of it to get a flat FR and all you have in the upper sections of your measurement are carefully crafted and placed distortion products, not even a bit of signal left. But you have your flat FR.

So, it should be clear that FR is a hilariously limited dimension to audio reproduction. It completely disregards time (something we are orders of magnitude more sensitive to) and has limited correlation power to our perception of quality. It is not a good quality metric at all. The extensions to it (a spinorama for example) has a much higher degree of correlation and actually carries useful information, but it is subject to the same critique and it is not reduceable to a number, not even a line. I really don't think these are useful metrics for consumers.

On the one hand I find the ASR crowd interesting and interested, on the other hand the discussions quickly descend into the typical neophyte behavior, completely voiding the value of it. The largest value I get from there is finding out if a given product is electrically hygienic and a look at the build quality and techniques. Most of what tries to relate to performance quality is too far removed from what a hypothetically perfect metric would let us know to be more than noise with an ego, especially when it comes to loudspeakers.

That said, I use FR measurements and low density spinoramas all the time as a tool to design loudspeakers. But it is one tool among many the tool box, and it is not more important than several others.

 

[pjwd]

QUOTE="henrich3, post: 863566, member: 20257"]
I agree with you that he's biased towards measurements, but he also does subjective listening tests in his reviews. Do you believe that his "measurement bias" makes his conclusions less credible? In my mind his extensive measurements give more weight & credibility to his subjective conclusions.
[/QUOTE]
In the particular example you gave I wonder if the kippell system can measure a dipole in the nearfield as you need distance to resolve the rear wave cancelation and supporr frequencies ... not doubting they measure poorly but there would need to be very specific input and smart math to predict a farfield response .. in that case the room takes over anyhow.
Linkwitz measured outside and up high to remove reflections.
I recall magneplain never submitted for reviews that measured
Cheers
Phil

 

[schlager]

What are the round things covered by wood in the front? Are those the base horns?

Is there any parametric equalizer anywhere in the system? is there any DSP anywhere in the system?

That is absorbers to remove the 1. reflection floor bounce. The "wood" is Rockfon tiles that is on top of a whole bag of Rockwool insulation. What you will typically se in a FR measurement from most speakers, is big cancellation suck outs in the 100-400 Hz area due to floor/ceiling bounce. I find that critical as many instruments and voices have their fundamentals in that area and that will leave them a bit lean and with less body, so to speak. The rectangular synergy horn is literally sitting on top of the bass horns. 2 extra bass horns are in the back of the room for a multi sub bass setup.

Yes I use DSP and DRC to sew the system together seamlessly.

 

[schlager]

Pretty good indeed !
Are you using a acourate or similar as a crossover.
Is the reflection at just under 2ms a floor reflection
Cheers
Phil

Thanks, yes I use DRC Designer, which is similar to Acourate, just different GUI. It's based on the same psychoacoustic algorithms and the author of Acourate also worked together with the author of DRC Designer. You could throw Audiolense in that bucket to, all 3 of them is basically doing the same.
I use MiniDSP for x-over as it can not be done in DRC Designer.

 

[Gregadd]

I am not qualified to comment on the accuracy of his measurements. I am however very familiar with his approach to the evaluation of audio equipment. To say he is biased toward measurements is putting it lightly.it

I agree with you that he's biased towards measurements, but he also does subjective listening tests in his reviews. Do you believe that his "measurement bias" makes his conclusions less credible? In my mind his extensive measurements give more weight & credibility to his subjective conclusions.

First of all allow me to reveal my bias towards him. He banned me from ASR.
IMO he does not put any stock in subjective listening test
It just civer for his all to frequent hatchet jobs on products he feels do not follow his technical prejudice

He did a similar hatchet job on Marton Logan.

 

[Keith_W]

So when a lot of people on this forum, claims that the objectivist are only looking at graphs, the at least give us an example of such a person. Otherwise it is just strawman argumentation, that only serves to confuse and ridicule those who (also) have a serious approach.

Here is one example. For some reason, ASR has deleted his (Uwe's) original posts so you can only see his replies quoted in other posts. For context: 64 Audio Trio IEM's are measured. They perform quite well, but people balk at the $2500 asking price. Some people jump in and say that their Truthear Zero IEM's also comply with the Harman curve and "outperform" the 64 Audios simply on the basis of published measurements. None of them have heard the 64 Audio IEM in question, and they base their assessment purely by looking at graphs.

So, it is NOT a strawman. It is totally true. I post more on ASR than I do here, and I see examples of this behaviour all the time. A bad review based on a limited set of steady state measurements = huge pile on by people who hate high end audio.

For example, it is widely known that any measured frequency response obtained from headphones is variable - depending on measuring rig, whether a HATS (Head and Torso Simulator) was used, whether the pinna and ear canal resembles a human ear canal or not, measurement protocol, clamping pressure, adequacy of seal, insertion depth (for IEM's), and so on. To add insult to injury, the measured frequency response is not the same as what you will hear, because of differences in head width, clamping pressure, seal, shape of pinna and external auditory canal, and so on.

Yet the measurement crowd ignore this and boldly state (in that thread that I linked above) that all headphones that measure the same will sound the same, to the extent of dismissing and rubbishing products they have never heard or evaluated themselves.

Don't forget that confirmation bias works both ways, and nothing causes confirmation bias more than knowing the frequency response beforehand. I am convinced this is why so many people on that forum love the Truthear Crinacles and Dan Clark Stealths for their superb measurements and compliance to the Harman curve. I bought both products. I found the Truthears unforgivably bright, and the Stealths to be damp sounding and lacking in treble. Yet they both comply with the Harman curve ... on their test rig. On my head it's a different story. At least I know what I am listening for, having experience with hundreds of headphones and hifi setups. Those guys have convinced themselves that Truthear IEM's are a gift from god and nothing else can possibly be better.

 

[schlager]

So, it is NOT a strawman. It is totally true.

Well you presumably found one, but I don't see that as a generally rule amongst the objectivists. We actually also listens to verify the sound, why would we not? It took me about 2 months and more than 50 filter configurations to arrive to a DRC filter, that I found realistic and pleasing, to my ears. Since then, about 2 years, I haven't touched the DSP/DRC, just enjoying the music. Fortunately, people who have had a sit in the sweet spot agrees, call me lucky

 

[Keith_W]

Well you presumably found one, but I don't see that as a generally rule amongst the objectivists. We actually also listens to verify the sound, why would we not? It took me about 2 months and more than 50 filter configurations to arrive to a DRC filter, that I found realistic and pleasing, to my ears. Since then, about 2 years, I haven't touched the DSP/DRC, just enjoying the music. Fortunately, people who have had a sit in the sweet spot agrees, call me lucky

I didn't find one. I found a whole community of them Just look around that place and you will see that a LOT of people will dismiss equipment they have never heard purely on grounds that it does not measure properly. Look at all the hatred for valve amps, turntables, and high end audio. Then there are another bunch of people who think that 44.1kHz/16 bits is all that you need, and there are even extremists who think that MP3 is all that you need.

They do this without evaluating it themselves, and even if they did, they "hear no difference". If you go into a listening test convinced that you will not hear a difference, the result is that you will hear no difference - even if there is one. Another example of confirmation bias. This lack of exposure to high end audio, with an unshakeable belief that it is all snake oil, that their $100 DAC's outperform MSB and DCS means that they wallow in a pitiful low end cesspool of horrible sound which they have convinced themselves is superior to any high end audio and we are all audiophools.

I am an objectivist too. Well, a strange hybrid of both ... call me a subjectivist-objectivist. I know what subjective results I want, but I use objective methods to get there. But I still believe that I will not dismiss anything without having the opportunity to listen for myself first. Being a hybrid sometimes puts me at conflict with extremists on both sides so it's not an easy road to follow.

There are still a lot of things we can not measure and do not know. Can't measure soundstage depth or width. Can't measure dynamics (and no, it's not the step response). In 25 years of hi-res audio, there have only been two DBT's published in JAES. One which was very flawed (negative result), and the other conducted by a person with vested interest in high-res (positive result). So we still don't know if hi-res is audible or not and it comes down to personal opinion. We know pitifully little about psychoacoustics - the last time I looked at it, most of the research was focused on hearing aids, industrial applications, etc. and very little on music enjoyment apart from very few papers from Harman.

 

[Ron Resnick]

100-400 Hz area . . . I find that critical as many instruments and voices have their fundamentals in that area

+1