Salar, how much an improvement is the Sabre to the PCM54? Is there any "strength" of the PCM54 compared to the Sabre?
Please not that this device is very old and it does not have the best specs either. A WM8804 can do this better (less jitter). WM8804 is 3.3V logic though, please keep that in mind with interconnecting to older stuff.
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I see, but problem is, our ears are not as good as our eyes with o'scope, aren't they. But that's technical description... thanks, I'll move on to better chip
Hmmmm? I couldn't make my mind before trying all kind of modifications, because what we hear is not the DAC itself (but I/V, LPF, opamp, jitter, etc.). The good thing about PCM54HP is that it is very big so easy to tweak. Besides, I have quite a few of "J" and "K" grades.
But I don't want to waste my time if the final outcome will be dissatsifying. I have AK4318 on going (because the size is quite big for an SMD) but I also interested in my Wolffson chips (small smd, but I think the sound is "uniquely" positive).
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That's what I thought. But how about that SAWTOOTH thing described by Salar?
Nico Ras in another thread mentioned how he thought more or less "DAC wont make any audible difference".
And what will likely be that one thing? That I shouldn't have wasted my time on low spec chip?
Because, if I picked different chip, I might as well learn other things.BACK TO TOPIC
I don't understand what is the point of building quality CD mechanism if it contributes little to the sound...
In my country you can find in abundance fine working old Pioneer laser disc players. This proved that this machine is very tough. I have many of them and they worked just fine (other newer players have went out of order many times)...
These players use PD2026/PD2028/PD2029 Pulseflow DAC from Pioneer. Thorsten Loesch in an old thread mentioned that these are among a few Delta-Sigma DAC that sound "engaging". I have never modified this but may be I will...
Inspired by this thread, I opened one CLD-1750K and plan to make top loading CD mechanism out of it. Then at the same time I might modified the DAC analog circuitry (they use terrible opamps, which might be why they sounded that cheap)...
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Hi Jay,
-Chris
You need a very good transport to feed the DAC with good information. That's why the short lived fad of pairing a cheap player with a good DAC died out. Feed the DAC garbage and you get compromised audio as a result. Another case of "garbage in, garbage out". The transport is critical to the quality of sound you get.
Knowing what doesn't work is often more valuable than succeeding the first time out. You have to then learn why you didn't get the results you wanted. You can then use what you have learned with other DAC chips (in this case).
-Chris
I would just like to say that I read the full thread yesterday and I learned quite a lot from the exchanges between Chris and Mark early on.
There are millions, if not billions, of cd's out there in people's possession. Something is going to have to play them in the future. Already I've seen laser replacement units for my players, all Marantz SA-8260's, get expensive and in short supply. Hard to be future proof I guess.
They left something out of the "perfect sound forever" slogans......
There are millions, if not billions, of cd's out there in people's possession. Something is going to have to play them in the future. Already I've seen laser replacement units for my players, all Marantz SA-8260's, get expensive and in short supply. Hard to be future proof I guess.
They left something out of the "perfect sound forever" slogans......
I got 10 Sharp Diodes from this seller today:
5pcs LT022MC Sharp Can 3 | eBay
They are meant to test ways to align the diffraction grating.
The photo shows how they were packed, no ESD protection to my eye at all.
Just the red foam, some plastic foil, a paper bag
Are they dead? Is there a quick way to test them without building them into a player?
5pcs LT022MC Sharp Can 3 | eBay
They are meant to test ways to align the diffraction grating.
The photo shows how they were packed, no ESD protection to my eye at all.
Just the red foam, some plastic foil, a paper bag
Are they dead? Is there a quick way to test them without building them into a player?
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Hi Salar,
Sure, pull the flexible PCB off an installed laser head and insert one of your new ones. Power up the CD player and measure the light output.
Just for the heck of it, I bought a cheap DA converter board from an Ebay seller that uses the PCM5102. It doesn't have to be great. I'm only trying to find a way to get audio from an old OMS-7. It was $13 USD, so what the heck? I've been meaning to get my feet wet in this stuff. This will hopefully make a good test module, a known quantity for testing.
-Chris
Sure, pull the flexible PCB off an installed laser head and insert one of your new ones. Power up the CD player and measure the light output.
Just for the heck of it, I bought a cheap DA converter board from an Ebay seller that uses the PCM5102. It doesn't have to be great. I'm only trying to find a way to get audio from an old OMS-7. It was $13 USD, so what the heck? I've been meaning to get my feet wet in this stuff. This will hopefully make a good test module, a known quantity for testing.
-Chris
Thanks a lot. Somebody guessed that the pink foam on
the photo where the lasers stick in is conductive. Can anybody confirm?
About light output: I cab not measure lase power, only if the laser lights up i.e with a Digital camera wich reads infrared light.
About the OMS-7, Version 1. It is Philips based thus it might already use i2s as
transmitting Format, but I am not sure. Many Dacs and probably SPDIF Transmitters read I2s, but I am also not sure on this.
the photo where the lasers stick in is conductive. Can anybody confirm?
About light output: I cab not measure lase power, only if the laser lights up i.e with a Digital camera wich reads infrared light.
About the OMS-7, Version 1. It is Philips based thus it might already use i2s as
transmitting Format, but I am not sure. Many Dacs and probably SPDIF Transmitters read I2s, but I am also not sure on this.
Hi Salar,
The pink foam is very probably an anti-static. That might mean that it doesn't generate a static charge rather than being conductive. Conductive materials are usually black because that is the colour of the material that is conductive. It feels "soft" in the fingers.
Yes, this OMS-7 ver.1 is out of the ordinary for sure. I may need to create some glue logic to convert the signal into something usable. I'll know once I get a chance to play. I have to get the audio data stream when it is still one stream as they split is into L and R early.
-Chris
The pink foam is very probably an anti-static. That might mean that it doesn't generate a static charge rather than being conductive. Conductive materials are usually black because that is the colour of the material that is conductive. It feels "soft" in the fingers.
Yes, this OMS-7 ver.1 is out of the ordinary for sure. I may need to create some glue logic to convert the signal into something usable. I'll know once I get a chance to play. I have to get the audio data stream when it is still one stream as they split is into L and R early.
-Chris
Could you make an acctual messurment of your Sabre dac?
How many bits left at the output, because I have tried many dacs,but nothing sounded better, close to the real life sound then my old TDA1540 with 14 bit.
Its much easer to make a perfect 16 bit then a 24 bit dac.
Your PS supply never going to be free of noise on that level.
44.1/16 NOS, 0.1 LSB (15.9 bit resolution), 1 / (44,100 * 1) / (2^16 / (1 / 0.1)) = 34.6ps.
44.1/16 NOS, 0.01 LSB (15.99 bit resolution),1 / (44,100 * 1) / (2^16 / (1 / 0.01)) = 3.46ps.
96/24 NOS, 0.5 LSB (23.5 bit resolution), 1 / (96,000 * 1) / (2^24 / (1 / 0.5)) = 310 femto seconds.
96/24 NOS, 0.1 LSB (23.9 bit resolution), 1 / (96,000 * 1) / (2^24 / (1 / 0.1)) = 62 femto seconds.
192/24 NOS, 0.5 LSB (23.5 bit resolution), 1 / (96,000 * 1) / (2^24 / (1 / 0.5)) = 155 femtoseconds.
192/24 NOS, 0.1 LSB (23.9 bit resolution), 1 / (96,000 * 1) / (2^24 / (1 / 0.1)) = 31 femtoseconds
1000 femtoseconds equal 1 picosecond.
1000 attoseconds equal 1 femtosecond, 1000,000 attoseconds equal 1 picosecond.
Failing to meet above jitter requirements, leads to (substantial) loss of resolution.
Jitter sensitivity rises rapidly with higher sample rates and oversampling.
Ecdisegns mentioned an messured Sabre dac once:
"It also is worth noting that in terms of raw, direct resolution (not noise shaped) only the PCM1704 exceeds the TDA1541 among audio DAC's in current production, while the ESS Sabre Reference bring about equal amount of raw, non-noise shaped resolution to the table and the whole rest cannot manage even in theory 16 Bit performance without 40dB or more noisgaping."
"Example: PCM1794A. THD+N at 0dB is 0.0004% (at 44.1kHz SR and 4.5V output). That makes -108dB."
And that makes it 17.9 Bit equivelent, 3 to 4 Bit short of your claim.
More interesting, doubling Sample Rate reduced this by another 6dB or 1 Bit every time it is doubled, so at 192KHz this DAC is down to less than 16 Bit equivalent resolution at 0dBfs!
A non-oversampling TDA1541 at 192KHz practically matches that!
In one world your old dac is just fine. The cd is 16bit player so why do you want intermodulate the original signal??
Just improve the power supply on the dac and its will be fine.
24 bit dacs never messured more the 18-20 bit in the laboratory with pristine clear power supply. Technicly impossible to reach those numbers.
Sorry for the OFF Topic but cannot see people still believe in this market hype.