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Question about class D

Naja

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So, I got a new class D amp (TPA3255) to replace my old AB amp, all in all I think it sounds much better than the AB amp, but I have one big gripe with it.

I noticed this without listening for it, compared to the AB amp it makes music faster, like there is no space between one note and the next.

I have to say it changes the music in an unfavourable way, it still sounds amazing but I don't think that's the right sound. Because if I plug my headphones in my computer that sounds like it's supposed to, meaning the right tempo, not faster.

I searched all over the internet for an answer on why it might sound faster but didn't find anything. I was hoping someone more knowledgeable than me could provide some insight on why this happens.
 

RayDunzl

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I noticed this without listening for it, compared to the AB amp it makes music faster, like there is no space between one note and the next.

I have to say it changes the music in an unfavourable way, it still sounds amazing but I don't think that's the right sound. Because if I plug my headphones in my computer that sounds like it's supposed to, meaning the right tempo, not faster.

If you still have your old amp:

Plug the left channel of the source into the old amp and speaker.

Plug the right channel of the source into the new amp and speaker.

See if they play at the same tempo.
 
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Naja

Naja

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If you still have your old amp:

Plug the left channel of the source into the old amp and speaker.

Plug the right channel of the source into the new amp and speaker.

See if they play at the same tempo.
Great idea, I'll do that later tonight and give an update.
 

DJBonoBobo

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See if they play at the same tempo.
Idea for a new high end boutique product: The Slodomizer™ – plug it in, pick a tempo and be satisfied.
 
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Naja

Naja

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If you still have your old amp:

Plug the left channel of the source into the old amp and speaker.

Plug the right channel of the source into the new amp and speaker.

See if they play at the same tempo.
I checked and there was no difference, both amps working in unison we're able to generate a good phantom image and had the same tempo. I probably got the feeling the class D was faster because it's more detailed than either my AB amp or headphones.

At least now I have a better understanding of how tricky our own perceptions can be, and I realized how certain audiophiles swap a 20$ cable for a 2000$ one and hear a difference.
 

Jim Shaw

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It's true, ever so: beauty is in the eye (ear) of the beholder. Much of what you perceive is a result of your past. We are not born with a lot of hearing acuity innate, so it's learned by experience. And this also occurs over the short term. What you hear depends somewhat on what you heard a few minutes or hours ago. [ie: If you don't like that Wharfedale, were you just before listening to a Klipsch?]

Much of component "break in" is due to this*: it takes a little while for new tonality to become your 'standard.' Until then, the new will be the different, and the old your standard. Soon, the new tonality will become your standard (even if you're not entirely satisfied with it). Some folks hear 'different' as better; some hear it as 'worse.' Honor your own neuroses. ;)

We revel in just detecting a difference. My (and your) ears aren't golden, except to us. It's why subjective reviews are so hard to calibrate by us.
.....
*Although there's also good evidence to believe that components do change a little over time, especially when new.

-Just one man's view.
 

DVDdoug

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"Faster" and "more detailed" are audiophile words with no real fixed definition. Sometimes distortion is described as "more detail"!

like there is no space between one note and the next.
An amplifier can't do that... That would require some advanced processing... ;)

The sound quality of an amplifier is determined by noise, distortion, and frequency response.
For any decent amplifier, distortion and frequency response are usually better than human hearing (unless the amp is over-driven into distortion) but there can sometimes be audible background noise (hum or hiss).

Audiophoolery

What is a blind ABX test?
 

RayDunzl

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I checked and there was no difference, both amps working in unison

Yup.

I applaud you for trying my somewhat silly suggestion.

I probably got the feeling the class D was faster because it's more detailed than either my AB amp or headphones.

There might be a difference.

At least now I have a better understanding of how tricky our own perceptions can be

That's a good thing to know about.

Eyes aren't much better.

My favorite optical trick.

The squares marked A and B are exactly the same shade of gray.

1669844692110.png


Copy and Paste:

1669845249496.png

Even when you know the trickery, it's impossible to un-see it.
 
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horias2000

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Make sure you are not using a Blutooth source to play music. Sometimes some dodgy BT transceivers may alter the tempo (pitch). I think it has something to with the supply voltage and the clock generating circuit. I have this in my car (2020 Ford Focus) There are moments when the pitch of the music is modified, either too slow or too fast. This only happens when I listen through BT. If I plug in the USB cable, I do not have this issue.
 
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Naja

Naja

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Make sure you are not using a Blutooth source to play music. Sometimes some dodgy BT transceivers may alter the tempo (pitch). I think it has something to with the supply voltage and the clock generating circuit. I have this in my car (2020 Ford Focus) There are moments when the pitch of the music is modified, either too slow or too fast. This only happens when I listen through BT. If I plug in the USB cable, I do not have this issue.
I'm using both Bluetooth and wired but there's no difference between them, I have a dac with its own internal clock that cleans up timing errors from the digital inputs.
 
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