Pasithea, the new flagship DAC of Sonnet. I Google this brand came Cess the same Founder as Metrum acoustics.
Both Sonnet and Metrum produce R2R DAC and now they combine together.
Front panel made by Aluminum, others chassis portion should be SPCC or SECC with black painting.
The ID is so simple that I can't come out any word to commend it.
Back panel, there are IEC, 2x trigger, USB/Toslink/I2S over RJ45/AES/Coaxial input, XLR/RCA output
USB module can be swap as other RJ45/HDMU I2S input module.
Base plate, use as SPCC with through hole for thermal. Those feet were teardown by owner before shipped to me.
Inside, it can separate as three portions. Main carrier board, Transformer and Display panel
Rest boards are USB module, SPDIF receiver and 8pcs DAC module. MQA module didn't install on this pic.
AC input used EMI filter and connector to main board and transformer through fuse and voltage select cable.
Those angle on PCB came from a Taiwan company called Telos who claims the current direction of AC power.
Telos provided service that they measured the phase of AC power and fuse, install the correct direction of fuse will bring good sound.
For me, this company is cheating to end customer because those two fuses used in different AC input, one is for 110V and one for 220V.
The transformer came from Amplimo 30VA 15Vac 1A*2, I am not familiar with it.
The output side put a DC to DC module from TRACO POWER which provide digital power source 5V.
Display control board, there is one jump wire on it but should be no effect on sound quality.
USB input module used Amanero solution. But it can't use Amanero driver even the same chip solution.
Those pins are skew because the height between USB and MB is too short that need to solder pins manually.
The relay used to switch idle mode of power.
SPDIF receiver used AKM AK4113, unfortunately they didn't use AK4118 which is better one but AK4113 is still ok.
There are many multiplexers 74HC157, probably used for switch I2S signal between AK4113 and USB module.
The DAC card, Pasithea used 8pcs of DAC cards more than lower level DAC Morpheus.
The right side is analog output connect to XLR and RCA connector.
DAC card looks like sandwich, there is a bare PCB stick with glue to cover IC on DAC card.
The left side slot is for MQA decoding card, this is a good design that users no need to pay for MQA forcibly.
The analog power used two sets of LM317/337 for ±12V. The OPA227 used to change reference voltage for volume control.
There is a -10dB HW mode on Pasithea by switch jumpers, this mode will reduce voltage output of OPA227 down to 0.53V.
Output, it used AD8055(or OPA810 in later version) to transfer as single end RCA then connect to LM317 in bottom side.
I don't quite understand how this circuit to be honestly. Probably LM317 used to reduce DC offset output since no AC coupling caps.
those jumpers used to switch output voltage level (-10dB mode).
The main caps used Kemet (or Samxon / CDE in later version) ELG 22000uF 25V*2, the D2D caps used Samxon 2200uF 25V*2
The reference voltage output caps used Samxon 1000uF 16V
And I also did some MOD, basically I changed analog power solution.
which bring slightly improvement measured by RMAA
or 0.8dB THD+n compared to original performance, the higher harmonic distortion reduced more.
Temp may reduce around 2deg C under room temp 29deg C.
Both Sonnet and Metrum produce R2R DAC and now they combine together.
Front panel made by Aluminum, others chassis portion should be SPCC or SECC with black painting.
The ID is so simple that I can't come out any word to commend it.
Back panel, there are IEC, 2x trigger, USB/Toslink/I2S over RJ45/AES/Coaxial input, XLR/RCA output
USB module can be swap as other RJ45/HDMU I2S input module.
Base plate, use as SPCC with through hole for thermal. Those feet were teardown by owner before shipped to me.
Inside, it can separate as three portions. Main carrier board, Transformer and Display panel
Rest boards are USB module, SPDIF receiver and 8pcs DAC module. MQA module didn't install on this pic.
AC input used EMI filter and connector to main board and transformer through fuse and voltage select cable.
Those angle on PCB came from a Taiwan company called Telos who claims the current direction of AC power.
Telos provided service that they measured the phase of AC power and fuse, install the correct direction of fuse will bring good sound.
For me, this company is cheating to end customer because those two fuses used in different AC input, one is for 110V and one for 220V.
The transformer came from Amplimo 30VA 15Vac 1A*2, I am not familiar with it.
The output side put a DC to DC module from TRACO POWER which provide digital power source 5V.
Display control board, there is one jump wire on it but should be no effect on sound quality.
USB input module used Amanero solution. But it can't use Amanero driver even the same chip solution.
Those pins are skew because the height between USB and MB is too short that need to solder pins manually.
The relay used to switch idle mode of power.
SPDIF receiver used AKM AK4113, unfortunately they didn't use AK4118 which is better one but AK4113 is still ok.
There are many multiplexers 74HC157, probably used for switch I2S signal between AK4113 and USB module.
The DAC card, Pasithea used 8pcs of DAC cards more than lower level DAC Morpheus.
The right side is analog output connect to XLR and RCA connector.
DAC card looks like sandwich, there is a bare PCB stick with glue to cover IC on DAC card.
The left side slot is for MQA decoding card, this is a good design that users no need to pay for MQA forcibly.
The analog power used two sets of LM317/337 for ±12V. The OPA227 used to change reference voltage for volume control.
There is a -10dB HW mode on Pasithea by switch jumpers, this mode will reduce voltage output of OPA227 down to 0.53V.
Output, it used AD8055(or OPA810 in later version) to transfer as single end RCA then connect to LM317 in bottom side.
I don't quite understand how this circuit to be honestly. Probably LM317 used to reduce DC offset output since no AC coupling caps.
those jumpers used to switch output voltage level (-10dB mode).
The main caps used Kemet (or Samxon / CDE in later version) ELG 22000uF 25V*2, the D2D caps used Samxon 2200uF 25V*2
The reference voltage output caps used Samxon 1000uF 16V
And I also did some MOD, basically I changed analog power solution.
which bring slightly improvement measured by RMAA
or 0.8dB THD+n compared to original performance, the higher harmonic distortion reduced more.
Temp may reduce around 2deg C under room temp 29deg C.
