Best spec ADC Chip currently.... ??

[Kessito]

1) no, DSD there made from PCM.
2) yes.
3) single, and today I finished APU modification - LPF is deleted, 48VDC phantom power added. Also, I bought cheap but seems quite typical Rode NT1 to find the optimal gain APU's switch +?db/+60db. 3.5mm jacks.
4) no such plans so far to make ADC/DAC device.

most pro microphones have sensitivity in the range 3-50mV/pa
so that means 94dBSPL gives 3-50mV rms output
the quitest mics ( ie akg c414 https://www.akg.com/Microphones/Condenser Microphones/C414+XLII.html ) have a single range of ca. 6dBSPL to ca. 140dBSPL so 134dB dyn range.
at a sensitivity of 23mV/Pa
so: 23mV -88dBV is about the lowest and 6Vrms about the highest

 

[IVX]

thank you, Rja4000 already consulted me about that, and thank Rja4000 one more time.

 

[Volikovvv]

Hi IVX, im very interested in purchasing cosmos dac, please let me know how to get it? When release date is scheduled?

 

[staticV3]

Hi IVX, im very interested in purchasing cosmos dac, please let me know how to get it? When release date is scheduled?

It will be sold on the E1DA AliExpress store: https://www.aliexpress.com/store/5142044
A scheduled release date does not exist.

 

[Volikovvv]

It will be sold on the E1DA AliExpress store: https://www.aliexpress.com/store/5142044
A scheduled release date does not exist.

Thank you for so fast response, im just looking for good balanced dac, without whistles and multiple features) sad to say, I purchased smsl d1se and hear sound coloration with default settings

 

[trl]

It will be sold on the E1DA AliExpress store:

I see it's still in stock, so why "it will be sold"?

Direct link to Cosmos: https://m.aliexpress.com/item/1005003391728199.html, I see Grade 1 available today.

 

[staticV3]

I see it's still in stock, so why "it will be sold"?

Direct link to Cosmos: https://m.aliexpress.com/item/1005003391728199.html, I see Grade 1 available today.

Volikovvv is interested in buying a Cosmos DAC, not the ADC.

 

[trl]

Man, I didn't realized that, thanks.

 

[Kessito]

will the cosmoc dac have i2s input?

 

[IVX]

Kessito, the proto has no but I can consider that option if any reason.

 

[Kessito]

Kessito, the proto has no but I can consider that option if any reason.

that would be very nice to have! I use my cosmos adc connected to a adau1452 dsp board and than connected over spdif to my rme soundcard, I would do the same with cosmoc dac.
( your electronics are awesome, but rme's drivers are just without any doubt the best out there, and have been since the 90's).

 

[dominikz]

that would be very nice to have! I use my cosmos adc connected to a adau1452 dsp board and than connected over spdif to my rme soundcard, I would do the same with cosmoc dac.
( your electronics are awesome, but rme's drivers are just without any doubt the best out there, and have been since the 90's).

That sounds very interesting! Could you perhaps provide more details on your setup?

 

[Kessito]

That sounds very interesting! Could you perhaps provide more details on your setup?

Sure, I use a hifiberry beocreate DSP board (just because I had it lying around) which has an analog devices ADAU1451 DSP and decent power supplies onboard.

I connect the Cosmos with I2S to the DSP board (I abuse the RPI pins for this)

The DSP can have the Cosmos as clock master or can use onboard samplerate convertors.
The Board has spdif in TOSLINK out (only goes up to 192kHz but thats fine for me), which I connect to my RME babyface pro

 

[capslock]

DonH56 Comtrue has no any recommendation regarding the quartz crystal just "12MHz" that's it. Previously used Epcos has 0.2% of the fail-rate, it is not a spectacular result but still ok to me. YXC 12MHz had ZERO% at 1000pcs batch.
View attachment 153065

I was really amazed to see the excellent jitter performance in Archimago's review!

So is this a simple crystal or a canned oscillator?

From what I understood from the discussion here, this is a simple crystal, and the analog gain stage lives on the Comtrue interface chip together with all the noise digital gates? Wow!

In the old days of curing CD players of jitter, you'd never ever want to use the gain stage that was on the servo or digital filter chip. Better use a separate HCU gate or even better a transistor or an ECL gate and then use another separate buffer chip to send out the master clock to all chips that need it.

And the sampling clock for the ADC is generated via digital PLL inside the Comtrue chip from the 12 MHz clock that has no common divider? Another wow! I never thougt PLLs could get this good!

 

[IVX]

not so optimistic )) Comtrue is a slave, and its 12MHz crystal used only for USB communication, 9822 is master with NDK 2025 osc.

 

[Veri]

I was really amazed to see the excellent jitter performance in Archimago's review!

So is this a simple crystal or a canned oscillator?

From what I understood from the discussion here, this is a simple crystal, and the analog gain stage lives on the Comtrue interface chip together with all the noise digital gates? Wow!

In the old days of curing CD players of jitter, you'd never ever want to use the gain stage that was on the servo or digital filter chip. Better use a separate HCU gate or even better a transistor or an ECL gate and then use another separate buffer chip to send out the master clock to all chips that need it.

And the sampling clock for the ADC is generated via digital PLL inside the Comtrue chip from the 12 MHz clock that has no common divider? Another wow! I never thougt PLLs could get this good!

The Sabre will be leveraging its jitter suppressing capabilities and not so much the Comtrue, I'd think.

 

[capslock]

Ok, so it is an oscillator, not a bare crystal. How do you get both multiples of 44.1 and 48 kHz? Separate oscillators or a nifty PLL?

 

[ChUmI]

I juste measured my E1DA Cosmos ADC 'A-Greade' with REW using SMSL M400 (AK4499EQ) as a signal source. In mono mode it shows THD+N below -121dB! Worst harmonics stays around -140dB To be honest, this is first time I see such a values at home. Thank You Ivan

 

[ChUmI]

My setup

 

[IVX]

ChUmI, well, I do design only what I like to use. Nobody design a decent ADC for audio measurement for $100-200 , hence, I have to do that
BTW, not all 100% of Cosmos ADC has 3rd harmonic as low as -140db. Average is -138db, worst ADC unit had -134db, the best one -145db or less but it is rare.
Be aware, that 3rd harmonic noticeable depends on the ADC temperature, so try to keep it warm(I calibrate ADCs at 27C). Very soon I'll offer a tiny thermostat PCBA for ES9822 chip, which will keep the ADC chip temperature around 50C, if the ambient is too cold. The PCBA is 5x5mm heater with a thermometer onboard. To install the thermostat need to glue that on the top of ES9822 IC, and connect two wires 5VDC and GND.