My Gosh - I have the exact same thing!! (Just ask my wife...) I never knew there was a name for it. I know what ADHD is because I've heard of it, but never AOID. I suppose you're just making this up...
The poor bathroom cabinet frame refinish just sits for months now, mostly because I cant figure out how to sand one part without cross-grain sanding another - am I supposed to sand with better than 1mm resolution over inches of length? Demo the whole thing, sand it and reassemble?
The Lounge conversations are - somehow - a lot more interesting than figuring out that one (and if anyone has input, I'd be glad to hear it)
AOID in not well documented in the literature... mostly because I suspect the cure rate is so low. Also that wives and loved ones are hesitant to accept the fairness that the failure to perform everyday work functions as tedious and boring are completely coverable by a legitimate medical condition or illness.
As far I can tell, when I perceive 'smearing' its not due to timing errors, its distortion. HF distortion in the main.
A little snippet from Bruno Putzeys:
Even the tiny little bit of aliasing left by standard half-band filters (20.000kHz to 24.100kHz) that you can only just tease out visibly using the square wave test is enough to make sibilants and breathing in A/B miked material spread out across the whole stereo image (an effect we're almost used to attribute to the miking method).
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Sibilance seems to be something I'm (we?) are quite sensitive to, I believe I heard a difference in a preamp listening test PMA did between two amps with different bandwidths.
So is sibilance what ‘smearing’ sounds like?
I was under the impressing smearing was a timing misalignment.
I was under the impressing smearing was a timing misalignment.
Sibilance is an aspect of speech, which probably explains why we are particularly sensitive to it when it doesn't sound as we expect it should.
I agree with this, although I am unsure of how 'smearing' is universally understood. I take it to mean that the harmonic resolution and the inner dynamics of those harmonics is being lost as a consequence. Is this to the extent whereupon you are finding that bass lines and drums can also be similarly affected?
I am unsure of what is meant by the "little bit of aliasing left" as to "tease out visibly using the square wave test". This seems to suggest that a square wave is necessarily an aliasing artifact causing the "material spread". If this is the case I would tend to disagree with this.
In a current test using a TDA1541a DAC the bandwidth of the I/V was set to 1.5MHz using a polystyrene capacitor. In a square wave test using a 44.1KHz the result was far beyond what can be described as a "teased out" residual of 44.1KHz. In lowering the bandwidth by using higher values of capacitance the result was of what might be described as 'smearing'.
This suggests that smearing is dependant upon the linear quality of networks attached as subsequent to whatever residual, or otherwise, square wave is presented to the network attached. Further that the capacitors causing bandwidth alterations or limitations could also be the cause of the smearing.
Is slew rate (transient response) tied to the dac (op amps) ?
If opamps in the dac are a mismatch to the amplifier could that be a source of smearing?
Edit.....might also explain why some get ‘better’ results by op amp rolling?
If opamps in the dac are a mismatch to the amplifier could that be a source of smearing?
Edit.....might also explain why some get ‘better’ results by op amp rolling?
'Smearing' means different things to different people. In the MQA marketing blurb there's 'temporal smearing' but I'm clueless about that. The kind of smearing I mentioned isn't that kind, I'd call it 'spatial smearing' - making an HF sound element less distinctly placed on a L/R line between the speakers. Sibilance is certainly one example of that.
Opamps in the I/V stage certainly can be a source of sibilance (sometimes called 'detail'). I reckon this kind of false detail is caused by exposure of the (bipolar) input stage of an opamp to excessive levels of RF.
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Not usually the way I would use the term 'smearing.' However, I could see why some types of sibilance might be called that.
IIRC sibilance at one time was used in reference to higher frequency vocal sounds, such as 'ess.' Too much FR up centered around 6kHz or so was associated with it, and a little EQ dip up there could be use to reduce audibility of the effect. That's how automated de-esser VST plugins work, they are band limited compressors used to attenuate excessive ess sounds in a vocal track.
For me it’s the harshness of the esssss sound in vocals , also carries over to the sssst sound of cymbals.
I'd suggest its IMD which is triggered by those 'essss' and gives the effect of an HF boost in and above the 'presence' frequencies. I have a few recordings which exhibit the effect to varying degrees. But sibilance can also be like Mark describes it, purely as the result of a bump in the FR in that range.
To me it's always connected with vocals, speech mainly, the upper frequency EQing and the causes during vocalisation are mentioned here Sibiliance: Definition, Frequencies & Tips For Controlling Vocal Sibilance
I have a Sonance amp that brings it out in spades....no matter what you do with the input levels. Did it since new, I relegated it to sub duty......no more sibilance!
From Wikipedia: "In phonetics, sibilants are fricative consonants of higher amplitude and pitch, made by directing a stream of air with the tongue towards the teeth."
This is to first consider that sibilants are naturally occurring events, that in the context of audio production, or reproduction, can be falsely presented in existence, character, or weight. This makes it difficult to evaluate in terms of what is false sibilance in terms of reproduction alone.
One of the mechanisms personally used in evaluating sibilance is in the comparison of the relative relationship with frequencies lower down in the vocals perhaps. This is to suggest that if vocalists lack weight in the lower registers, as must also be considerate of miking, this becomes cause for concern. This is notwithstanding that the sibilance can sound real.
Another consideration is if the whole of the reproduction, in the global sense, has an overall frequency presentation shifted upward more globally. This can be particularly problematic in a system that is highly analytical in form.