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The Rational Audio System

watchnerd

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"I have become convinced that we now live in an age where it should be possible to reproduce a signal accurately in the frequency and time domains, yet at reasonable cost. A rational set of design goals would be:

  1. Basic linearity. Many high-end systems seem to disregard this aspect, or it is branded as ‘un-musical’.
  2. Bass response. Systems should have bass that goes all the way down.
  3. Time domain accuracy. Regardless of cost, very few systems actually provide this.
In other words, my argument is that we should simply ditch every arbitrary distortion of the signal if we can. Is there a sensible argument that says we should not do this? By steadfastly obeying common sense and refusing to be swayed by romantic notions, I think that a genuinely great system could be built from generic components for a few hundred pounds – not the price of a Bentley."

More at: http://www.hifizine.com/2014/12/the-rational-audio-system/

A good read, much seems to be aligned with @Cosmik 's thinking.

No magical fuses for @Thomas savage , though.
 

Thomas savage

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"I have become convinced that we now live in an age where it should be possible to reproduce a signal accurately in the frequency and time domains, yet at reasonable cost. A rational set of design goals would be:

  1. Basic linearity. Many high-end systems seem to disregard this aspect, or it is branded as ‘un-musical’.
  2. Bass response. Systems should have bass that goes all the way down.
  3. Time domain accuracy. Regardless of cost, very few systems actually provide this.
In other words, my argument is that we should simply ditch every arbitrary distortion of the signal if we can. Is there a sensible argument that says we should not do this? By steadfastly obeying common sense and refusing to be swayed by romantic notions, I think that a genuinely great system could be built from generic components for a few hundred pounds – not the price of a Bentley."

More at: http://www.hifizine.com/2014/12/the-rational-audio-system/

A good read, much seems to be aligned with @Cosmik 's thinking.

No magical fuses for @Thomas savage , though.
Fair read, when you find some exclusively rational humans let me know..

It would be good for us to put together a system , a ASR approved set of components that provide the kind of performance this artical is promoting. I think I mentioned the idea some time ago, amirs the best one to do it after a forum consultation. Then he could test the whole system.

I'd like to see maybe a custom assembled system, nothing too intense it requires a EE qualification but home assembled to reduce cost and provide some fun as some guys like fart arsing about with screwdrivers etc..

Oh I have no 'magic fuses' just ordinary ones these days.. But the spare fuse area of the fuse holder is filled with blu tack so you can carry on taking the piss out of me at every turn .
 

Purité Audio

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A decent pair of actives and an iPhone.
Keith
 

Purité Audio

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OP
watchnerd

watchnerd

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Oh I have no 'magic fuses' just ordinary ones these days.. But the spare fuse area of the fuse holder is filled with blu tack so you can carry on taking the piss out of me at every turn .

I have a tube preamp and actively listen to LPs about 25% of the time, so I have no room to talk.
 

amirm

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The introduction was good but the ending of him thinking that DIY speaker gets him there, not so much. We don't hear like a single microphone. We hear with two ears the combination of direct and indirect sounds. Unless he measures all of that and verifies with some blind experiments, he is tooting his own horn unfortunately. Only excellent speakers yield themselves to DSP processing.
 
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watchnerd

watchnerd

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The introduction was good but the ending of him thinking that DIY speaker gets him there, not so much. We don't hear like a single microphone. We hear with two ears the combination of direct and indirect sounds. Unless he measures all of that and verifies with some blind experiments, he is tooting his own horn unfortunately. Only excellent speakers yield themselves to DSP processing.

Isn't the entire premise of digital room correction based upon optimizing for what the microphones "hear" at the listening position?
 

amirm

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Isn't the entire premise of digital room correction based upon optimizing for what the microphones "hear" at the listening position?
Only in low frequencies below 200 to 300 Hz. Correction above that must be done/verified a) by ear and b) with speakers that have similar direct and indirect response.

Longer explanation, once the waveform of sound becomes small relative to the dimensions of our body/head then psychoacoustics becomes significant as does the differential between what the two ears hear. A single microphone cannot capture any of this.

For these reasons in my system I have Dirac turned off above 200 Hz. I tried full correction and while it sounded better on some tracks in general it had a negative effect.
 

amirm

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Is this based on the Schroeder frequency or psychoacoustics?
Both. Schroeder says there will be large frequency response variations. Psychoacoustics says they are readily audible and as low as 0.5 db if they are broad enough.
 

oivavoi

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I've read about his system before. I find it very intriguing. And I really like his no nonsense approach to hifi! It's like he says: the goal should be to reproduce the signal as faithfully as possible. Nothing more fancy than that.

Amir: I don't think he uses room correction in his system, it's driver correction only. And apparently the software is pretty complex. Furthermore, the two best systems I've heard in my life have been DIY. So it's certainly possible to get there using DIY... but probably not easy!

Where I think this article is not complete:
- I doubt he's managed to get rid of all loudspeaker distortion, referring back to the distortion in loudspeakers thread. Especially given that he uses cheap drivers. Driver distortion is apparently not that easily measured.
- I think of his design as an example of a minimum requirement all loudspeakers designs should strive for: as little distortion as possible in all regards (time, frequency, etc). Just letting the signal through. But I don't think his particular design is the final answer for all people. Beyond signal linearity, there is still the question of dispersion pattern - front-firing box? Dipole? Horn? Omni? And should a speaker be dynamic or electrostatic? I doubt you can find a "rational" answer here which can be applied to all cases. I think it may be down to room acoustics, and preference. I tend to like both omnis, dipoles and big horns better than box speakers. But I'm not sure if that preference is "rational".
 

amirm

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Amir: I don't think he uses room correction in his system, it's driver correction only. And apparently the software is pretty complex. Furthermore, the two best systems I've heard in my life have been DIY. So it's certainly possible to get there using DIY... but probably not easy!
I realize that but he needs to measure on and off-axis fully and then weigh them to know how the speakers sound. Getting flat on-axis response alone does not do it.
 

fas42

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We are much better off than say 30 years ago in buying gear off the shelf that will give a decent measure of what's possible, in raw form. Judicious, cost effective combinations will yield excellent dynamics, though the majority still fall well short of what they theoretically should deliver - unfortunately, the issues of low level distortion, interference are still almost completely ignored by the industry, meaning that certain types of recordings are always a struggle to make sound good. If one ditches these, and only plays "compatible" tracks then generally a good listening experience at low cost can be had by anyone.
 
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