TDA 1540 NOS – Non Over Sampling good idea.?

TDA 1540 NOS – Non Over Sampling good idea.?  Truncating 2 bits ?

Some qoutes from internet

“Absolutely no doubt that this mod has a fantastic effect on the sound, there’s no going back to OS for me!”

“The sound is unique, sweet, clear and full of detail that the newest cutting edge delta sigma DAC can never produce. If you haven’t taste this kind of sound before it’s definitely a regret for an audiophile. It’s like compare Vinyl and CD, Rollling shutter and global shutter in the DSLR.”  ?

Is removing the SAA7030  a good idea ? please read — Digital-to-analog conversion in playing a Compact Disc

 

A Modification board ” NOS plus reclocking.?! ” , this board shift 2 audio bits

Timing to TDA1540 After modification , dumping 2  LSB bits without adding dither  , why.? , it will increase quantization noise

Now the measurements

Philips CD 204 Orginal

With NOS modification , increased distortion

Mutltitone -20 dBfs 20-96000 Over Sampling

Mutltitone -20 dBfs 20-96000 Non Over Sampling ,  high frequency roll-off , and aliasing products above 22.5 kHz

Multitone -20 dBFs 20-96000 Hz compare Over Sampling vs Non Over Sampling  Log

Multitone -20 dBFs 20-96000 Hz compare Over Sampling vs Non Over Sampling  Lin

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Freq. Sweep Non Over Sampling 0dB fs , `High freqeuncy roll ons 

 

Freq. Sweep Non Over Sampling -1dB fs close-up

1 kHz -20 dBfs compare Over Sampling vs Non Over Sampling

1 kHz -60 dBfs compare Over Sampling vs Non Over Sampling

THD measured in Philips CD 104 with NOS Modification + Reclocker