Q how much does upsampling improve the sound (detail etc)?
and wouldn't this need to be done as close as possible to the data source?
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The CS8420 based upsamplers all sound different and don't improve detail; I think the improvement may be due to the DAC having a brick wall filter at twice or four times the base frequency.
You need to invest in a serious upsampler; a used Assembalge D2D should not cost too much; but the dCS Purcell or dCS972 is something else - much much much better.
You also need a serious dac. I like CD upsampled to 176.4 much better than 192 ie 4x44.1 kHz.
and wouldn't this need to be done as close as possible to the data source?
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The CS8420 based upsamplers all sound different and don't improve detail; I think the improvement may be due to the DAC having a brick wall filter at twice or four times the base frequency.
You need to invest in a serious upsampler; a used Assembalge D2D should not cost too much; but the dCS Purcell or dCS972 is something else - much much much better.
You also need a serious dac. I like CD upsampled to 176.4 much better than 192 ie 4x44.1 kHz.
Tyimo said:
Belt drive CD transport! Like the CEC-TL0-X or Parasound CBD200....
You are joking!?
fmak said:Q how much does upsampling improve the sound (detail etc)?
and wouldn't this need to be done as close as possible to the data source?
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The CS8420 based upsamplers all sound different and don't improve detail; I think the improvement may be due to the DAC having a brick wall filter at twice or four times the base frequency.
You need to invest in a serious upsampler; a used Assembalge D2D should not cost too much; but the dCS Purcell or dCS972 is something else - much much much better.
You also need a serious dac. I like CD upsampled to 176.4 much better than 192 ie 4x44.1 kHz.
176.4/44.1 =4
192/44.1 =4.3537414............etc
mathematically it doesn't add up
Who said sound is not a science?
what is the iput and output of these upsamplers? i2s
allan
fmak said:
<snip>
I like CD upsampled to 176.4 kHz.
<snip>
If all you want is a higher sample rate there is no need to spend a fortune. The SAA7220 will get you to 176K for less than the price of a top ten CD.
rfbrw said:
If all you want is a higher sample rate there is no need to spend a fortune. The SAA7220 will get you to 176K for less than the price of a top ten CD.
I thought the saa7220 was a digital filter?
allan
--------------------------------------------------------------------------------rfbrw said:
If all you want is a higher sample rate there is no need to spend a fortune. The SAA7220 will get you to 176K for less than the price of a top ten CD.
When did I say that; you haven't really taken in what I said.
awpagan said:
I thought the saa7220 was a digital filter?
allan
It is.
fmak said:
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When did I say that; you haven't really taken in what I said.
I have fully taken in what you'written. You prefer audio at a higher sample rate. There are a number of ways to achieve this and not all require a second mortgage.
------------------------------------------------------------------------------rfbrw said:
It is.
I have fully taken in what you'written. You prefer audio at a higher sample rate. There are a number of ways to achieve this and not all require a second mortgage.
Each to his own. You want to pay 1p, I have tried it and prefer the result of spending £1
Not hindered by any Knowledge (as my Father said)
To write the data to the DRAM? The read-out is done with the master-clock hence that one matters........
Tyimo said:Hi!
Belt drive CD transport! Like the CEC-TL0-X or Parasound CBD200....
Greets:
Tyimo
To write the data to the DRAM? The read-out is done with the master-clock hence that one matters........
fmak said:
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Each to his own. You want to pay 1p, I have tried it and prefer the result of spending £1
The ratio is probably about right but my 1p goes alot further than your £1.
Just to point out - all upsamplers are digital filters. The only difference is if you are an engineer or a marketdroid. But there are filters and there are filters. A carefully implemented, many tap, FIR will beat any of the off the shelf single chip wonders that are commonly used to create oversampling filters. Oversampling and upsampling are very closely related although not quite identical issues. The main difference being that a properly designed oversampler can take into account the exact realisation of the DAC architecture in the filter design.
Heavens only knows why belt driven CD drives arrived. In a correctly designed system there is clearly no possibility of them changing the data timing. In a badly designed one, yes. One could theorise about lower servo power supply noise etc etc. But unless the only thing one changed in the system at all was the drive mechanism - and left power supply, optical assemply, servo mechanisms, servo drivers, digital control, all the same - well you actually don't know what made the difference.
Heavens only knows why belt driven CD drives arrived. In a correctly designed system there is clearly no possibility of them changing the data timing. In a badly designed one, yes. One could theorise about lower servo power supply noise etc etc. But unless the only thing one changed in the system at all was the drive mechanism - and left power supply, optical assemply, servo mechanisms, servo drivers, digital control, all the same - well you actually don't know what made the difference.
Just to throw in a potentially crazy idea, but this is a DIY forum after all.
Has anyone considered using a CPU for the digital filter, or a general DSP? I haven't done any calculations, but supposedly a modern CPU would be fast enough to do the job, and it would offer a lot of flexibility to experiment with whatever type of digital filter you could imagine, by not being specifically tailored to implementing certain types of filters? I am sure this wouldn't be economically or practically reasonable for any, but possibly the most high-end commercial models, but for DIY, why not?
Another equally crazy idea would be to use upsampling to very high frequency and use a computer graphics card for the DAC, or maybe just use such a DAC. They're usually only eight bits, but that should be compensated by the upsampling. I do realize there could be problems to make a low-jitter clock at those frequencies, though. Maybe the graphics card could even be programmed to do the filtering? Using OpenGL to program your CDP, chew on that one.
Has anyone considered using a CPU for the digital filter, or a general DSP? I haven't done any calculations, but supposedly a modern CPU would be fast enough to do the job, and it would offer a lot of flexibility to experiment with whatever type of digital filter you could imagine, by not being specifically tailored to implementing certain types of filters? I am sure this wouldn't be economically or practically reasonable for any, but possibly the most high-end commercial models, but for DIY, why not?
Another equally crazy idea would be to use upsampling to very high frequency and use a computer graphics card for the DAC, or maybe just use such a DAC. They're usually only eight bits, but that should be compensated by the upsampling. I do realize there could be problems to make a low-jitter clock at those frequencies, though. Maybe the graphics card could even be programmed to do the filtering? Using OpenGL to program your CDP, chew on that one.
I thought this thread was:-
1. fit new clock
2. get rid of feedback op amp Iv
3. sort ground out!
objective = improve sound
What I want to know about is the varying impedance with frequency of the feedback opamp IV....
Anyone got a graph or a formula to hand ?
Cheers,
Ashley.
1. fit new clock
2. get rid of feedback op amp Iv
3. sort ground out!
objective = improve sound
What I want to know about is the varying impedance with frequency of the feedback opamp IV....
Anyone got a graph or a formula to hand ?
Cheers,
Ashley.
Christer
look at the meridian gear
ash_dac
seems to have wondered off
clock yes done
"What I want to know about is the varying impedance with frequency of the feedback opamp IV...."
opamp iV i think desiigners use them to balance for output load,
probably easier?
we need that answered from an EE
as for ground
my question was iec cord (3 pin) rather than 2 pin cord
allan
look at the meridian gear
ash_dac
seems to have wondered off
clock yes done
"What I want to know about is the varying impedance with frequency of the feedback opamp IV...."
opamp iV i think desiigners use them to balance for output load,
probably easier?
we need that answered from an EE
as for ground
my question was iec cord (3 pin) rather than 2 pin cord
allan
Absolutely, look at Wadia gear.Has anyone considered using a CPU for the digital filter, or a general DSP?
They have filters that don't ring in time, absolutely fantastic stuff.
But thread is 3 things to improve on CD players sound, and does not have to be limited to the very 1st posted opinion.
I hope someone can provide an order of importance.
I just replaced some 5532 in my CD player, goodbye soggy sound.
Tom
EE
tmblack said:
Absolutely, look at Wadia gear.
They have filters that don't ring in time, absolutely fantastic stuff.
But thread is 3 things to improve on CD players sound, and does not have to be limited to the very 1st posted opinion.
I hope someone can provide an order of importance.
I just replaced some 5532 in my CD player, goodbye soggy sound.
Tom
EE
tom
which opamps did you goto?
hope you used sockets.
If opa's, carlosfm's info on decoupling is worth it.
have you removed the mute transistors yet?
as for order of importance.
start with the simple and cheapest thing first?
allan
Christers idea of processor controlled
I think this maybe this
http://www.meridian-audio.com/p_g61.htm
search for "jocko low noise oscillator " finds it everytime:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=6194&highlight=
also here:
http://www.diyaudio.com/forums/showthread.php?postid=32772#post32772
and while you're at it, you can peek here, too ...
http://www.diyaudio.com/forums/showthread.php?s=&threadid=6121&highlight=
mlloyd1
http://www.diyaudio.com/forums/showthread.php?s=&threadid=6194&highlight=
also here:
http://www.diyaudio.com/forums/showthread.php?postid=32772#post32772
and while you're at it, you can peek here, too ...
http://www.diyaudio.com/forums/showthread.php?s=&threadid=6121&highlight=
mlloyd1
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