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Deleted member 537459
I listen to impressions of @andrea mori's dac lite
https://www.diyaudio.com/community/...discrete-dac-with-digital-calibration.386076/
https://www.diyaudio.com/community/...discrete-dac-with-digital-calibration.386076/
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Deleted member 537459
I don't know why it was closed, I don't think I did anything wrong, however it is well known that @ andrea-mori's material here is not well seen by everyone, however it was written by a "simple" member who had to be posted in the commercial section. so they deleted the threath without giving any reasons, not closed, deleted ...
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Deleted member 537459
Anyway i try in commercial section:
Since Andrea was kind enough to lend me his first prototype of the DAC Lite, I start this thread to share my listening impressions and some technical observations provided by Andrea.
Firstly the technical aspects.
The DAC Lite is a multibit discrete DAC. The resistor ladder network is segmented, the first 3 MSBs are thermometer decoded while the other 20 LSBs are R2R decoded.
The DAC implements a sign magnitude architecture to get bipolar output, so there are 2 x 23 bit ladder for each channel, one for the positive rail and one for the negative rail.
The dirty signals like bit clock and data are optically isolated to avoid any interference with the latch signal wich drives the DAC switches.
The bit clock is stopped as soon as data have been loaded into the shift registers, so every time the DAC switches to a new word the bit clock cannot affect the latch.
It uses a custom protocol provided by the TWSAFB-LT FIFO Lite.
The FIFO Lite also provides a digital calibration for the DAC Lite in order to compensate the error due to the resistors tollerance used in the ladder.
It's a voltage output DAC which provides 1.1V to 1.8V rms depending on the Vref power supply, from 3V3 to 5V. The output impedance is 625 ohm, so the DAC can drive directly most amplifiers.
There is an optional buffer if the load wich has to be driven is lower than 20K.
Since this is the first prototype, the board is very large and a bit difficult to manage, but Andrea told me that the final board is much smaller, 163x140 mm (picture attached).
Premise:
I've been doing all-round liquid music research and development for about 5 years,
I started with a simple sabre 9023 then moved on to a sabre 9038q2m to arrive in 2019 at @iancanada's fifopi with its 9038q2m dual mono, first with his battery system, immediately abandoned on the operamp burson, then later also on everything else. mounted the lundahl transformers and then the fantastic and for me the best listened to today, the transformers of ivan @bisesik.
then I switched to the single and after dual mono 9038pro, I also had the software made to disable dpll and always go in sync with the output transformers.
pushed by bisesik, I tried the legendary tda1541a first with the cards of @ryanj and fifopi, then with the fifo of @andreamori.
This for me was the best listening ever, compared with many expensive ones like, dcs bartok, lumin t1, aqua la scala mkII, northstar supremo, playback design mpd-08 etc.
Most of the time both the owner and I agreed on the superiority of my latest setup. (always with Ian's fear as Andrea's has too little possession)
And now my first listening impressions.
after having mounted the dac the first impression is the shocking dynamics, already the tda1541a is incredible, but the daclite is far superior, but without ever breaking down.
this dynamic is dressed in an incredible detail that never tires of listening, in fact the musicality is incredible.
the feeling is to hear just the analog sound.
The soundstage is well detailed with each instrument in its focused place, but not small, lifelike size. The tda1541a tends to round and amalgamate the information a little.
The bass, the elasticity, the extension, the dynamics on the chest, the incredible control. The contrabass materializes, you see it well focused but at the same time a big sound and it detaches completely from the speaker… incredible.
The organs in the church ... incredible cleanliness, if you close your eyes you have the perception of the height and depth of the church.
The brass (trumpet and ecc.) takes on an impressive realism, you really feel the vibration of the breath not to mention that you feel the emission point but at the same time the sound that expands with crazy speed.
all tests were done with oscillators drixo 5/6 supply with shunt-inductive supply
Then later I added the buffer, which improved a bit on every aspect. In my case it did some good.
What can I say I do not want to add anything else, I can only say that I am not aware of the price of the final card, but I can say that we hardly find material of this level.
Thanks to @andrea_mori for having the opportunity to try out his preview material.
Since Andrea was kind enough to lend me his first prototype of the DAC Lite, I start this thread to share my listening impressions and some technical observations provided by Andrea.
Firstly the technical aspects.
The DAC Lite is a multibit discrete DAC. The resistor ladder network is segmented, the first 3 MSBs are thermometer decoded while the other 20 LSBs are R2R decoded.
The DAC implements a sign magnitude architecture to get bipolar output, so there are 2 x 23 bit ladder for each channel, one for the positive rail and one for the negative rail.
The dirty signals like bit clock and data are optically isolated to avoid any interference with the latch signal wich drives the DAC switches.
The bit clock is stopped as soon as data have been loaded into the shift registers, so every time the DAC switches to a new word the bit clock cannot affect the latch.
It uses a custom protocol provided by the TWSAFB-LT FIFO Lite.
The FIFO Lite also provides a digital calibration for the DAC Lite in order to compensate the error due to the resistors tollerance used in the ladder.
It's a voltage output DAC which provides 1.1V to 1.8V rms depending on the Vref power supply, from 3V3 to 5V. The output impedance is 625 ohm, so the DAC can drive directly most amplifiers.
There is an optional buffer if the load wich has to be driven is lower than 20K.
Since this is the first prototype, the board is very large and a bit difficult to manage, but Andrea told me that the final board is much smaller, 163x140 mm (picture attached).
Premise:
I've been doing all-round liquid music research and development for about 5 years,
I started with a simple sabre 9023 then moved on to a sabre 9038q2m to arrive in 2019 at @iancanada's fifopi with its 9038q2m dual mono, first with his battery system, immediately abandoned on the operamp burson, then later also on everything else. mounted the lundahl transformers and then the fantastic and for me the best listened to today, the transformers of ivan @bisesik.
then I switched to the single and after dual mono 9038pro, I also had the software made to disable dpll and always go in sync with the output transformers.
pushed by bisesik, I tried the legendary tda1541a first with the cards of @ryanj and fifopi, then with the fifo of @andreamori.
This for me was the best listening ever, compared with many expensive ones like, dcs bartok, lumin t1, aqua la scala mkII, northstar supremo, playback design mpd-08 etc.
Most of the time both the owner and I agreed on the superiority of my latest setup. (always with Ian's fear as Andrea's has too little possession)
And now my first listening impressions.
after having mounted the dac the first impression is the shocking dynamics, already the tda1541a is incredible, but the daclite is far superior, but without ever breaking down.
this dynamic is dressed in an incredible detail that never tires of listening, in fact the musicality is incredible.
the feeling is to hear just the analog sound.
The soundstage is well detailed with each instrument in its focused place, but not small, lifelike size. The tda1541a tends to round and amalgamate the information a little.
The bass, the elasticity, the extension, the dynamics on the chest, the incredible control. The contrabass materializes, you see it well focused but at the same time a big sound and it detaches completely from the speaker… incredible.
The organs in the church ... incredible cleanliness, if you close your eyes you have the perception of the height and depth of the church.
The brass (trumpet and ecc.) takes on an impressive realism, you really feel the vibration of the breath not to mention that you feel the emission point but at the same time the sound that expands with crazy speed.
all tests were done with oscillators drixo 5/6 supply with shunt-inductive supply
Then later I added the buffer, which improved a bit on every aspect. In my case it did some good.
What can I say I do not want to add anything else, I can only say that I am not aware of the price of the final card, but I can say that we hardly find material of this level.
Thanks to @andrea_mori for having the opportunity to try out his preview material.
As I wrote in our now deleted posts... I appreciate you reporting on this comparison. I think that many of us were curious to know if Andrea's plan to create this dac would ever be completed, and if it would yield the results he was seeking. I am quite familiar with Ryanj's TDA1541a implementation driven with iancanada's FifoPi and Andrea's clocks. Your impression that Andrea has improved on both Fifopi and on a well implemented 1541a is notable. I have no plans to change either as I have reached the 'good enough for me' status. Still a remarkable achievement.
Ilgavro - would you be able to explain a bit about your power supplies (I see some Mundorf caps poking out)? Have you tried different voltages to boost the output and I see you prefer the buffer in: what's the input impedance of your next stage?
I assume you prefer shunt regulation to batteries? Have you tried ultra cap/battery supplies?
I assume you prefer shunt regulation to batteries? Have you tried ultra cap/battery supplies?
D
Deleted member 537459
sorry for the late reply,
the power supplies have a rectification with schotly diodes, then filter resistors that also have the function of regulating how much current the shunt absorbs. then enters the inductance, from there. there is just the regulator that constantly absorbs current and keeps the voltage stabilized choice. a further note that there are no tl431 type voltage references which are noisy.
I also made some comparisons with the famous regulators such as lt3045, belleson, lt1963, lm317 etc. I found less noise both with an oscilloscope with a load, which when listening to the sound is noticeably more natural, elastic and analog.
I tested the voltage at 3.3vdc and 4vdc of the dac, without hearing big changes, just more volume at the same volume as the preamp.
I have not tried the power supply with S.caps, for a question of management-cost, moreover I do not believe in the miracle with a hybrid situation. it should be powered only with S.caps, but at what cost and what space for maybe an hour of listening.
the power supplies have a rectification with schotly diodes, then filter resistors that also have the function of regulating how much current the shunt absorbs. then enters the inductance, from there. there is just the regulator that constantly absorbs current and keeps the voltage stabilized choice. a further note that there are no tl431 type voltage references which are noisy.
I also made some comparisons with the famous regulators such as lt3045, belleson, lt1963, lm317 etc. I found less noise both with an oscilloscope with a load, which when listening to the sound is noticeably more natural, elastic and analog.
I tested the voltage at 3.3vdc and 4vdc of the dac, without hearing big changes, just more volume at the same volume as the preamp.
I have not tried the power supply with S.caps, for a question of management-cost, moreover I do not believe in the miracle with a hybrid situation. it should be powered only with S.caps, but at what cost and what space for maybe an hour of listening.
ilgavro- thanks for your observations on regs. I'm not sure I follow what regulator you ended up using?
FWIW I found the addition of small inexpensive 1.5F supercaps added to the +-5v consumers on a TDA1541a dac made a noticeable improvement. It already was a pretty good linear supply with 6th order clc filtering, salas shunt regs & lots of blackgate caps. Still, just adding a small $6 supercap made a marked improvement in those subjective sounds we seek. Don't know if it extends to these discrete R2R dacs but I just put it out there. Sound comparison before and after is at https://www.diyaudio.com/community/threads/diy-tda1541a-pcb-d3.328060/post-7009659
FWIW I found the addition of small inexpensive 1.5F supercaps added to the +-5v consumers on a TDA1541a dac made a noticeable improvement. It already was a pretty good linear supply with 6th order clc filtering, salas shunt regs & lots of blackgate caps. Still, just adding a small $6 supercap made a marked improvement in those subjective sounds we seek. Don't know if it extends to these discrete R2R dacs but I just put it out there. Sound comparison before and after is at https://www.diyaudio.com/community/threads/diy-tda1541a-pcb-d3.328060/post-7009659
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Deleted member 537459
For those interested in a comparison between dacs with andrea's fifo source:
https://www.diyaudio.com/community/...on-of-sound-quality-between-some-dacs.386815/
https://www.diyaudio.com/community/...on-of-sound-quality-between-some-dacs.386815/
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Deleted member 537459
Next listening session will include PCM1704, Ian’s ES9038 mono, Soekris DAM1021 and DAC Lite powered with shunt regulator Vref.
