It was a joke/rhetorical question. Use the search function if you really want to know. He also has a problem understanding the difference in voltage and current phases and thinks they are of much greater significance than they are.
You need to be aware that there are internet shills for audio business. They devised series of internet talks that are geared towards supporting the boutique audio electronics market. Many of them are pro at it and they've invested a lot of time crafting word salad to make it look "delicious".
Look what you can do with sinewaves, what makes you think transients and their decay, or anything else for that matter would be a problem to recreate?
Pure Fourier series animation montage - YouTube
Unfortunately, not everyone present can understand this. Apparently, this is a lack of education(
A DC signal is a continuous constant voltage of null frequency,
As group delay involves phase and frequency, you can't speak of a DC group delay.
What you may think of is a sudden injection of DC voltage at the input of an amplifier. This is a voltage step.
When such a step is applied at an amplifier input, there is a very very very short time delay due to the propagation of the signal in the path before the feedback signal begins to be substracted to the input signal.
We may consider that, during the very very very short time delay, there is no feedback which means that the amplifier is open loop and its error signal is extremely large and fast.
But an audio signal is limited in frequency and never looks like a step voltage so the error signal does not need to be large and fast.
By the way, do not discard this to stay in a real world :
forr, you too literally understand the meaning of the expression: "from direct current to ...." Of course, we are talking about alternating current, which is covered by the term "group delay time". But even a frequency of 0.001 Hz is already an alternating signal, not a direct current!
regards
Petr
Differences in the temporal structure of the signal, which have not yet been clearly defined, are significant for the auditory system, and it is from them that it determines live sound or distinguishes one speaker from another.
It is known that for undistorted signal transmission, the group delay time should be with a tenfold margin, that is, it should be constant in magnitude up to a frequency of 200 kHz.
Well, now look at which GVZ schedules meet this requirement.
This is the case in modern prestigious amplifiers - the signal propagation delay time does not exceed 100 ns! It is this value that guarantees the level of rapid distortions that do not negatively affect the sound quality.
It is known that for undistorted signal transmission, the group delay time should be with a tenfold margin, that is, it should be constant in magnitude up to a frequency of 200 kHz.
Well, now look at which GVZ schedules meet this requirement.
This is the case in modern prestigious amplifiers - the signal propagation delay time does not exceed 100 ns! It is this value that guarantees the level of rapid distortions that do not negatively affect the sound quality.
Attachments
Forgotten and ignored by the "alternative thinkers". ITD threshold of around 10us which is the only relevant time issue in a fit for purpose bandwidth limited audio system.
With two signals from two speakers it would require a larger time difference to shift the image away from centre.
I was wondering about it's relevance here Interaural Time Difference and the second link Jakob provided appears to answer my question.
I was wondering about it's relevance here Interaural Time Difference and the second link Jakob provided appears to answer my question.
The propagation delay time depends of the physical length of the feedback loop path, does'nt it ? Why should it be shorter in modern prestigious amplifiers (usually cumbersome) than in integrated amplifying circuits like a TDA2030 ?
It means that the brain does not analyze the content of the sound when it's less than 10 µs but considers it as a whole. The data of 10 µs may be not exact, but it is certainly more than 1 µs. In usual amplifiers, the propagation delay in the feedback path may be a few ns. If ICC, at 300000 km/s spead, a trip of a 30 cm or 1 ft takes1 ns.
If you are listening to a mono mid-frequency sound in a 2 channel stereo system and suddenly delay one channel's signal by 10us, the mono sound will move laterally a few degrees towards the other speaker.