speaker burn in

[avliner]

When a reviewer says that the speakers sounded terrible at first, then they let the speakers burn-in to get them to sound right - the review loses all credibility for me...

Totally agree with you on that one Cornelius

 

[ratso]

again, i am not an expert here. but as to some points i have seen mentioned here:

1. someone i think missed one of the links - he did test side by side not one woofer but actually 8 woofers side by side
2. he allowed them to cool for 2 hours inbetween tests. these are only like, what, 7" woofers? not sure how allowing a few days of cooling would change anything, cool is cool?
3. the changes broke a few rules that i thought were a given around here:

a) the changes were consistent throughout the 8 models ("it's probably just the speaker")
b) the changes were somewhat substantial - the last speaker on the graph seems like the most change ("if it does change, it's a change that doesn't matter")
c) the changes increased up to 80 hours of use ("if a spider does break in it just takes like a minute and then it's done").

but again, what i don't know is if these changes amount to something that you could hear. what i might be starting to change my mind about is the idea that speakers don't change over time - if these numbers are real then there is definitely a MEASUREABLE change going on here. i wonder if any of the Aholics guys have glanced at this what there take is?

 

[PENG]

Human detection is best in the mid bands, 1kHz-4kHz area. Low frequencies, especially where that f value is at, the detection of differences is not so good at all. Similarly as you go up in frequency. Level changes, frequency changes, etc.

I read about how tolerant we are to THD in the bass (20 to 240 hz) band. I forgot the number but it was supposed huge, i.e. something in the order >>10% THD and we could not easily detect it. Have you come across any publications on this?

 

[PENG]

again, i am not an expert here. but as to some points i have seen mentioned here:

1. someone i think missed one of the links - he did test side by side not one woofer but actually 8 woofers side by side
2. he allowed them to cool for 2 hours inbetween tests. these are only like, what, 7" woofers? not sure how allowing a few days of cooling would change anything, cool is cool?
3. the changes broke a few rules that i thought were a given around here:

a) the changes were consistent throughout the 8 models ("it's probably just the speaker")
b) the changes were somewhat substantial - the last speaker on the graph seems like the most change ("if it does change, it's a change that doesn't matter")
c) the changes increased up to 80 hours of use ("if a spider does break in it just takes like a minute and then it's done").

but again, what i don't know is if these changes amount to something that you could hear. what i might be starting to change my mind about is the idea that speakers don't change over time - if these numbers are real then there is definitely a MEASUREABLE change going on here. i wonder if any of the Aholics guys have glanced at this what there take is?

Again, I am sure there are changes taking place over time. The problem I have with those claims about about so many hours the thing open up the sound stage, the harshness are gone, the bass are tighter etc., are BS because there are simply too many factors such as room temperature, humidity, voice coil temperature and much more making it impossible for the designers/builders to allow for such variables in their design/build to achieve any consistent outcome in terms of performance vs working hours, let alone whether the final outcome (performance) will be audible and audibly better or not.

 

[Pyrrho]

I read about how tolerant we are to THD in the bass (20 to 240 hz) band. I forgot the number but it was supposed huge, i.e. something in the order >>10% THD and we could not easily detect it. Have you come across any publications on this?

It is higher than 100% (!!!) at 20Hz:

http://www.axiomaudio.com/distortion.html

For the range you are asking about, it can approach 20% before it is audible.

To quote the article:

The Results

While it is has been recognized for years that human hearing is not very sensitive to low bass frequencies, which must be reproduced with much more power and intensity in order to be heard, what these results show is that our detection threshold for “noise” (made up of harmonically related and non-harmonically related test tones) is practically non-existent at low frequencies. (The “noise” test tones are noise in the sense that they are not musically related to tones commonly found in musical instruments.) In fact, the “noise” tones at 20 Hz and 40 Hz had to be increased to levels louder than the music itself before we even noticed them. Put another way, our ability to hear the test frequency “noise” tones at frequencies of 40 Hz and below is extremely crude. Indeed, the results show we are virtually deaf to these distortions at those frequencies. Even in the mid-bass at 280 Hz and lower, the “noise” can be around -14 dB (20% distortion), about half as loud as the music itself, before we hear it.​

 

[mtrycrafts]

...

but again, what i don't know is if these changes amount to something that you could hear. what i might be starting to change my mind about is the idea that speakers don't change over time - if these numbers are real then there is definitely a MEASUREABLE change going on here. i wonder if any of the Aholics guys have glanced at this what there take is?

I mentioned that even Tom Nousaine measured changes of drivers in his papers but could not tell audible differences.
Not sure how Richard Pierce measured or how long he waited to cool off but he indicated that drivers did go back towards the original numbers, again, not sure if he mentioned how close.

 

[mtrycrafts]

I read about how tolerant we are to THD in the bass (20 to 240 hz) band. I forgot the number but it was supposed huge, i.e. something in the order >>10% THD and we could not easily detect it. Have you come across any publications on this?

That is just THD as Pyrrho indicated.
This is a JND experiment
http://home.provide.net/~djcarlst/abx_crit.htm

shifting the f3 a few Hetz is way less than a 1/3 octave and you can see how large the JND is at 1/3 octave and that is not music or sound effects but sensitive test tones.

I am amazed that some golden ears think that the ear/brain picks up everything. Far from the facts.

 

[PENG]

That is just THD as Pyrrho indicated.
This is a JND experiment
http://home.provide.net/~djcarlst/abx_crit.htm

shifting the f3 a few Hetz is way less than a 1/3 octave and you can see how large the JND is at 1/3 octave and that is not music or sound effects but sensitive test tones.

I am amazed that some golden ears think that the ear/brain picks up everything. Far from the facts.

Perhaps after they get sucked into spending way too much money on expensive electronics they became more prone to placebo or similar effects.

 

[zieglj01]

After owning more speakers than you can count on 12 hands - I can say for
the most part, that the speakers tend to break/burn me in. I have heard no
major difference after 24, 48, 72, 100 or 200 hours. A poor speaker is poor,
and a good speaker is good. Also, nothing will change a poor crossover.

 

[TLS Guy]

one of the things that seem to be disputed around here, and i have always agreed. recently, however, i ran across a couple of interesting articles that seem to show differently by danny the speaker builder who runs GR research. the interesting thing is he approaches this in a no BS sort of way and has a lot of numbers to back up what he says. hmm....

http://www.gr-research.com/burnin.htm

http://www.gr-research.com/myths.htm

Those number changes are insignificant, and will result in changes to bass tuning below the level of detectability by the human ear.

His findings are nothing new, and similar results have been published by many authors.

People seem to come in two groups.

I find most come to tolerate the most glaring of deficiencies over time. Although I think this is more pronounced in males than females.

Less common is the reverse where aberrations becomes less and less tolerated over time. I'm certainly in this group. However the bonus is it mandates continuous improvement and reassessment over time.

I think on the whole women are much less tolerant of faults in audio reproduction. In fact I think a lot of women can not tolerate a lot of systems, and find them not worth the trouble.

So take what women think of your systems seriously. More than likely that are noting something of significance.

 

[LAB3]

The one time I have noticed any difference in "Speaker Burn In" was last year I purchased a New pair of Audio Technica ATH-A700 closed design head phones. The first 15 minutes I was very Unhappy..... they were not as clear and volume was off. I had them plugged into my Revox. I read the Revox used a different Ohm then newer CD head phone jacks. I plugged them into my bedroom system and turned on FM,sounded someway better, I then turned them up to about 1/3 volume and let them play all night. Next morning WOW they sounded like a different set when I plugged back into Revox?????? I had read that "Cans" needed a break in but thought is was B.S.. I had cleaned the Revox head phone jack a week before so it was clean. I replaced a 12" woofer in my Klipsch sub ( I have a pair) and did not notice any difference as I turned off one and played it for 30 minutes and swapped them..I could not hear any difference. Why on the head hones and not on the 12" driver?????????

 

[mtrycrafts]

.... I then turned them up to about 1/3 volume and let them play all night. Next morning WOW they sounded like a different set when I plugged back into Revox?????? ...

The next day? Well, then we have to examine your memory and the quality of the testing protocols.

 

[LAB3]

The next day? Well, then we have to examine your memory and the quality of the testing protocols.

Umm I am 61 amd I do then to drink a beer or to many some Sat nights

I wanted to listen to them "Sooner" don't remeber reading any instructios for head phones. Oh well...they sound Great ..Now. Best $112.00 I have spent for good sound........ I take that back, my Klipsch Image S4 inner ear pods( Ipod) sure have Great treble. I guess stuck so far in my deaf old ears helps.

 

[humsin94]

Breaking-in is very reasonable from a materials point of view. Any string instrument player will tell you that the instrument's sound changes over a period of playing. Therefore, the wood cabinet in a speaker is also very likely to improve in sound with age.

Brasswind and flute players also zealously state that their metal musical instruments change over years of playing, the sound waves "aligning" the metal.

Based on observations of musical instruments, I believe that the materials within a speaker, such as the cabinets and drivers, do break in after a period of playing as the sound waves changes the molecular alignment of the materials.

 

[markw]

I really doubt the wood cabinets in speakers improve with age. ...think about it for a while.

 

[cpp]

I think the breakin takes place between our ears more than the speakers or cabinets.

 

[Pyrrho]

Breaking-in is very reasonable from a materials point of view. Any string instrument player will tell you that the instrument's sound changes over a period of playing. Therefore, the wood cabinet in a speaker is also very likely to improve in sound with age.

Brasswind and flute players also zealously state that their metal musical instruments change over years of playing, the sound waves "aligning" the metal.

Based on observations of musical instruments, I believe that the materials within a speaker, such as the cabinets and drivers, do break in after a period of playing as the sound waves changes the molecular alignment of the materials.

The wood in an instrument, like a violin, is made to resonate. It is very different from the typical speaker box, which is made to be as inert as possible; any sounds the box makes are distortion, not the signal from the speaker.

As for the claims of artistic types for what changes over time, that is no way to determine facts.

With a wind instrument, or a brass instrument, they are constantly getting spit in them, as one cannot help but release some spit occasionally while blowing.

Also, with something like a violin, if it uses the old fashioned gut strings, sweat and oils from the skin are absorbed into it, which affects it. Wood also absorbs such things, though with a proper varnish, that effect is minimized. That is not an issue with properly handled speakers, as one does not touch them normally.

However, I expect that a speaker might sound different if you sprayed it with sweat and oil, or spit, though it will all depend on how much sweat and oil, or spit, and what, exactly, the speaker is made of.

So, your analogy is not a good one at all.

 

[mtrycrafts]

...

Brasswind and flute players also zealously state that their metal musical instruments change over years of playing, the sound waves "aligning" the metal.

Please, expand on this some more. How do those players tested this claim? Sheer memory of what happened yesterday, last month, ten years ago??? Really??? You accept such nonsense claims???

If conductors cannot tell the material that was removed in a recording from the part that stayed in the recording at the time of this process, how would anyone remember what things sounded in the past???

Gould, Glenn, "The Grass is Always Greener in the Outtakes," High Fidelity, Aug 75, pg 54-59.

... as the sound waves changes the molecular alignment of the materials.

Is this a magnet being realigned???
Do you really believe this nonsense??? Better talk to a materials physicist first.

 

[LAB3]

I think the breakin takes place between our ears more than the speakers or cabinets.

I did not imagine my head phones were lacking more volume and bass right out of the box. I know at 61 my hearing is not as good as it was 30 years ago but I still hear volume just fine. It's still a speaker that got better after 12 hours of use when it was New. Burn in on "Cans" was true. Now my other speakers I purchased new in the last 40 years I never "Noticed "any difference??? I guess I have a Tin ear if other Klipsch owners noticed their Reference Series Klipsch change after they played them. It's been too many years on older Klipsch.... I did notice a difference when I installed Bob Crites new cross overs in my old 1979 Cornwalls and vey low volume they were off and scrtachie sounding (thought it was my AVR) not.... all is like new again.

 

[humsin94]

If modern science can explain everything and recreate mystical legends, why are violins over 300 years old so sought after? If wood is so "dead" as you describe, these multi-million dollar instruments should be easy to reproduce. Wood is an organic material. Age, climate, vibrations, etc, all affect its properties. I like to think of a speaker cabinet as a sound box. Much like in a violin, it is designed to be stiff, yet resonant.

fyi, Pyrrho, string instrument players change their strings at least once every 3 months, so string wear and tear is not really a factor. Most of the sound is affected by vibrations.

This article may be of interest: http://www.dalemfg.com/acousticaladjustment_021.htm

It shows how vibrations affects wood itself