In class means the same level of performance.
Our new Driscoll and Differential oscillators are in class with the best oscillators on the market (BVA and BT ULN).
We have measured them and we have published the phase noise plots.
The technical comparison demonstrates that we have reached at least the same performance, maybe better.
So a simple equation: if we assume the original DAM1021 as good as the 100000 USD MSB DAC, if I will improve the sonic performance with my update it will be better than the reference DACs on the market, so the absolute best.
But the above equation was written by others, not by me.
I'm the ordinary student applying the equation.
I've written it several times, it would take a little more humility.
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I'm trying to understand the architecture of the DAM ladder, there is something not clear about the 28 bit depth since the last 3 MSB resistors have a common node.
Strange, I have to investigate more.
Strange, I have to investigate more.
In class I would say means "in the same territory" - it could still be worse and comply to "in class with". But thats hair splitting and market speak.
Problem is that DAM has a sonic claim whereas you make a technical claim so they are not comparable really - are they? If you don't believe that there is an absolute relation between technical performance data and SQ? But you don't, do you? No.
So you are chasing a "market statement" about sound quality which isn't even measurable. I think most of us understood that when we pressed "purchase" on that 1021 Rev A it wouldn't really be a TotalDAC (whatever it might be - I never heard it) but we hoped for a really good one where all efforts, within the price point, was spent to reach the "promise".
I think it has. But one thing is a bit disappointing and that is that I know there is a potential improvement if the memory was to be expanded for the fifo in order to lessen the intensity of Si frequency adjustments. But I also know there is a shortage of memory in the DAM so maybe it's not even possible. But that hasn't been claimed as a reason not to. Your test here wont prove if it would.
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Problem is that DAM has a sonic claim whereas you make a technical claim so they are not comparable really - are they? If you don't believe that there is an absolute relation between technical performance data and SQ? But you don't, do you? No.
So you are chasing a "market statement" about sound quality which isn't even measurable. I think most of us understood that when we pressed "purchase" on that 1021 Rev A it wouldn't really be a TotalDAC (whatever it might be - I never heard it) but we hoped for a really good one where all efforts, within the price point, was spent to reach the "promise".
I think it has. But one thing is a bit disappointing and that is that I know there is a potential improvement if the memory was to be expanded for the fifo in order to lessen the intensity of Si frequency adjustments. But I also know there is a shortage of memory in the DAM so maybe it's not even possible. But that hasn't been claimed as a reason not to. Your test here wont prove if it would.
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Ok, we have a different point of view, I think it is a question of presumption.
And I believe one should be careful before claiming such that statements.
It is not a marketing question, it is a question of seriousness.
The shortage of memory has a simple solution, just install a SRAM chip like in our FIFO Lite.
But when someone thinks to be a smarter designer than John Curl and Nelson Pass there is no more room for suggestions.
Ths is the world 2.0, sorry I'm from the old school, just take a look at my avatar (CX-350, DHT triode type 50, USA 1924. Almost 1000 USD for a NOS/NIB pair some years ago... sigh...).
And I believe one should be careful before claiming such that statements.
It is not a marketing question, it is a question of seriousness.
The shortage of memory has a simple solution, just install a SRAM chip like in our FIFO Lite.
But when someone thinks to be a smarter designer than John Curl and Nelson Pass there is no more room for suggestions.
Ths is the world 2.0, sorry I'm from the old school, just take a look at my avatar (CX-350, DHT triode type 50, USA 1924. Almost 1000 USD for a NOS/NIB pair some years ago... sigh...).
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Well, we agree I suppose on that it is the SQ that matters. So until a session can be arranged to figure out which one of the DAM and TotalDac a bunch of listeners would prefer - without knowing which is which of course - we simply don't know.
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Are you seeing a market for fifo Lite for DAM owners?
A Frankenstien'd DAM is not so appealing to me.
But I'm still interested in your result and wish you happy hunting!
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A Frankenstien'd DAM is not so appealing to me.
But I'm still interested in your result and wish you happy hunting!
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Yes, but not an R2R DAC like euro21 stated, a plain R2R DAC in which the resolution is totally dependent of the tolerance of the resistors in the ladder.
The MSB and Soekris are R2R sign magnitude DACs, that have double R2R ladders for + and - to achieve a higher resolution than the tolerance of the resistors.
As I said several times we are not interested on market for our devices.
We are hobbyists without commercial interests.
The business is for the designer of the DAM that sells diy products and then does not support the users about tweaking.
However you can always ask the designer to improve the board, although John Curl Nelson Pass Charlie Hansen Thorsten Loesch Scott Wurcer does not care about the users suggestions.
BTW it will not be Frankenstein DAM junior, I believe a little board will fit the DAM, maybe removing 36 capacitors (I have to see if there is another way less invasive such as disconnect the power supply to the FPGA, to the micro and to the fabulous SI514).
Since the designer does not help it will takes a little time.
This is the story told by the designer.
Do you know the math of the sign magnitude DAC?
It has nothing to do with the resolution, or better the accuracy of the ladder due to the resistors tolerance.
With 0.01% resistor tolerance you get 14 bit accuracy, so 15 bit in sign magnitude notation since you are using 2 ladders with 14 bit accuracy each.
Nothing more, tales apart.
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Ok, now it's clear.
There are two 27 bit ladder networks, so 28 bit total.
The ladders are segmented.
The first 2 MSB of each ladder are thermometer's decoded (2 to 3) and followed by 25 bit R2R.
4 outputs of the registers are wasted (one for each 595).
These wasted outputs could be useful to extend the thermometer to the first 3 MSB (3 to 7) simply adding 4 resistors for each ladder.
Its' time to sleep.
Heh... Don't worth the game.
Even 20-bit AD1862 having laser-trimmed resistors will provide better linearity.
NOS DAC will suffer from aliases while oversampling DAC not so sensitive to domain conversion.
OK, if that could be done I'm sure there will be interested owners incl. myself. I assume there will be an i2s interface. Also toslink and coax?
Your dedication and stamina is admirable. Good luck!
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Your dedication and stamina is admirable. Good luck!
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This is your opinion, mine a little different.
The TDA1541A NOS DAC I have built for a friend is one of the best I ever heard, maybe the best.
However now you talk about the linearity, do you think that oversampling improve the linearity of the ladder?
If you think so you have not understood the math of the R2R ladder DAC, and maybe you are confusing with the ring DAC, that's a PWM DAC.
Finally when the architecture of the front end of the DAC is wrong the DAC structure does not matter, the DAC is not properly drived regardless of its structure.
This is the reason to throw out the front end.
The TDA1541A NOS DAC I have built for a friend is one of the best I ever heard, maybe the best.
However now you talk about the linearity, do you think that oversampling improve the linearity of the ladder?
If you think so you have not understood the math of the R2R ladder DAC, and maybe you are confusing with the ring DAC, that's a PWM DAC.
Finally when the architecture of the front end of the DAC is wrong the DAC structure does not matter, the DAC is not properly drived regardless of its structure.
This is the reason to throw out the front end.
The interface is the one of the FIFO Lite, it provides 4 x selectable I2S inputs.
S/Pdif and USB need a converter.
We will provide the converter boards or else you can use one of those on the market like Amanero, WaveIO, JLSounds for USB.
For Toslink and coax I have got a S/PDIF to I2s converter from Audiophonics for a few Euro.
You're missing an important part:
most of the time you don't have to switch the MSB bits in a sign magnitude DAC so they don't contribute to the linear distortion.
I think implementing bigger buffers with consequently increased latency is going about it the wrong way.
The correct approach would be to make the DAM1021 the master and simply slave the source to it. This would also enable one to perfectly sync multiple DAM1021s in a box.
I'm not sure if consumer devices like TVs regularly allow for external clocking, but it's no problem with even semi-professional audio interfaces.
This way you would have both - perfect timing where it matters and the lowest possible latency.
The correct approach would be to make the DAM1021 the master and simply slave the source to it. This would also enable one to perfectly sync multiple DAM1021s in a box.
I'm not sure if consumer devices like TVs regularly allow for external clocking, but it's no problem with even semi-professional audio interfaces.
This way you would have both - perfect timing where it matters and the lowest possible latency.
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It has nothing to do with the accuracy of the ladder network that depends on resistance tolerance and thermal drift and on the RDS On of the active devices used as the switches.
The ladder accuracy remains the same with both sign magnitude and two's complement notation.
As I said I cannot access the DAM firmware source code, so you have to ask the designer, good luck.
However our FIFO Lite was designed to listen to music at the best and not to watching video.
Sorry but we are not interested in movies, and at the end we are designing these devices for ourselves although we are sharing them with the audio community.
There are already too many people interested exclusively in the market on this forum, we are ordinary hobbyist.