Anyone can explain this info of CD Player

[sunade]

DAC: 16 bit linear 8fs digital filter

1 bit quartz time axis control

Frequency response: 20-20000 hrz. +1.5 db. -2.5db.

I don't know the meaning of these words. Could you please explain them? And

what is better than the other (1 bit VS 16 bit)? Is the higher amount frequency response better than the lower?

Thanks very much.

 

[Duncan]

Hi sunade...

It is up to each persons own preferences as to which DAC type is better... The very original DACs were 14bit (TDA1540), the next were 16bit, with no oversampling, which arguably meant that you would get 'echoes' in the sound (I forget how / why, but I am sure this is where Nyquists theorem comes into it - Edit, yes, it is - see here) which is why oversampling came into it, to push those echoes / artefacts into a range beyond human hearing...

Purists however have gone back to non-oversampling DACs of late because of the warmth of their sound...

1 bit quartz time axis control is just a pretty name for bitstream, think of this as a comparison between a 16 lane highway (16bit), where the vehicles all travel at 5mph but only need to travel 1 mile, whereas bitstream (1bit) is a single lane road, where the cars are travelling at 80mph and need to travel 16 miles to get to their destination... exactly the same journey time, just different methods of getting there...

re the frequency response, 20hz-20khz is the standard frequency range that a CD carries in its data due to limits in sample rate (44.1khz)... and, if reading the db readings in a literal context, this would mean that the bottom of the frequency range is boosted by 1.5db, and the top end is muted by 2.5db, when in comparison to a completely flat frequency range...

Apologies if this info is a bit muddled etc, am very tired at the moment, but - didn't want this thread to sink into the depths being unanswered.

I hope it helps

 

[sunade]

Thanks verymuch
very useful

 

[gregorio]

From the looks of it your CD DAC has 8x oversampling, which may or may not improve the sound quality. Oversampling was not brought in to stop the echos (alias images) in 16bit. There should not be any "echos" in CD unless there is a serious fault with the ADC. Oversampling was invented so that the anti-alias filter could be implemented in the digital domain rather than in the analogue domain, which helped reduce some of the artefacts of a steep analogue filter.

1bit vs 16bit has been (and is still) a topic of debate amongst both professionals and consumers for some time. As a general rule 1bit (SACD) tends to sound better, not because the specification is necessarily any better than CD but simply because the recordings tend to be made to a higher standard to cater for the more audiophile market with SACD.

G