Sonnet Audio Pasithea DAC Review.


It has been almost three years since I reviewed the Sonnet Audio Morpheus DAC. The test was of great interest because the Morpheus offered a lot of performance for the price in a relatively small space. Cees Ruijtenberg's latest creation is called Pasithea and is currently Sonnet's flagship DAC with twice as many custom-designed and built DAC modules and even higher performance, specs, lower noise, etc. Many of you were eager to learn more about Pasithea, so when Ruijtenberg suggested the review, I gladly accepted. 


Not only to serve our dear readers but also because I am always curious to see how far Ruijtenberg can raise the bar with his products.   

Pasithea


After completing the Sonnet Audio Morpheus, partly triggered by the shortage of components, Ruijtenberg began looking for new components. 


The idea was for the Pasithea DAC to operate at higher supply voltages so that noise would be further away from the music signal. He also looked for faster components to improve the current-to-voltage conversion. 


For this, it is important that the bandwidth is not determined by feedback, but that transistors have more linearity by themselves and can already have sufficient bandwidth without feedback.

These are the things that are significantly different from the modules used in Morpheus DAC. The Sonnet Audio was already asked if the new modules can be used in the older Morpheus. In itself, this may work because they are pin compatible, but it will lead to no effect because the motherboard is not suitable.


As mentioned before, a higher supply voltage and therefore more current is needed. To put this into practice, a two times more powerful power supply was mandatory.


The other request was a lower output impedance, which was reduced to 16 ohms using 4 DACs per channel. This allowed the Sonnet team to lessen the influence of cables to a minimum. Another goal was to use the Pasithea as a preamplifier for very sensitive power amplifiers, including tube-based amps.


Sonnet had already implemented this in the Morpheus MK-II DAC by using a passive attenuator and this was adopted in the Pasithea. However, in the case where the attenuator is used, an attenuation of 10 dB is created and the impedance is lowered to 8 ohms.


The new design was intended to improve the sound, but the chassis needs better ventilation. The high current caused by the current-to-voltage conversion with each of the eight modules reaching a final temperature of about 50 degrees Celsius required adjusting the enclosure accordingly.


Apart from the sonic qualities, the advancement can be seen also in the measurements. The noise floor has dropped to the -160 dB limit, where even the Sonnet Audio Analyzer has its limits to show the data. 


The linearity itself was always good, but the last bits in the noise have dropped away. Now that the noise has dropped about 10 dB, the last bits have become visible.

Sonnet has decided to give the Pasithea the same minimalistic esthetics so as not to drive the price even higher, and all the improvements are mainly visible on the inside. 


Operational


The Pasithea DAC, which is positioned above the Morpheus DAC, has better specifications and is more versatile.

The name Pasithea reflects and embodies relaxation and meditation. As you can read in this review, this unique sonic balance has succeeded and lives up to its name.


On the front, the left side is reserved for a volume/mute switch, followed by an LCD source selector button and an on/off switch.

The rear panel features an IEC connector, two remote control switches, one optical, one coaxial AES /EBU, as well as unbalanced and XLR-balanced outputs.


Flexibility has also been increased and inputs such as I2S and USB are standard without having to change modules.
 

The exceptionally energy-efficient electronics made it possible to fit even more high-end technology into the dimensions of the standard Sonnet enclosure.

As mentioned earlier, the eight SDA-3 modules developed for this design have a very low combined output impedance, so any load can be driven with ease.


Eight DACs were used to improve several specifications. Linearity, lower distortion even at extremely low levels, and a 10 dB lower noise floor than the Morpheus.

To control very sensitive electronics, it is possible to attenuate the signal by 10 dB via the menu, in addition to the physical attenuator, which also offers 10 dB attenuation. And all this with an extremely low impedance (XLR output), so that any amplifier can be driven with any sensitivity.

 
Special attention has been paid to linearity. Besides the fact that a DAC should have no errors so that the data in the digital domain matches the value in the analog domain, noise plays another important factor here. If the noise is low, it is possible to make the last steps visible, so that a true 24-bit performance is given.

The transparency and straightness desired and aimed for was a pure signal coming directly from the sound engineer's mixing desk in the studio, without any interference, degradation, or distortion. As you can discover in the following music section, this goal was successfully and potently achieved. 

The Music


For us to experience and comprehend music in its entirety, it is necessary to reproduce it in its absoluteness if we are to grasp its actuality.

While reproducing a human voice or a single instrument is already a challenge, reproducing multiple instruments, tones, sounds, etc. without masking effect is even more complex.

Here, usually, not only the focus, the three-dimensionality, and the clear position, but also the timbre of the voice or instrument can be changed.

Sonnet Audio Pasithea DAC is much better than usual to deal with these psychoacoustic phenomena and reproduce music much more vividly.

As usual, here are some reference titles/albums that highlight the qualities of Pasithea, including the abovementioned challenges. 


I am sure every SRV fan can appreciate and apprehend Dan Patlansky's "Big Things Going Down" from the album Move My Sou. I'll let the music speak for itself, but along with the masterful guitar playing, this song shines in showcasing the well-captured and recorded performance.

There is a clear distinction between drums, vocals, and guitar, and "Big Things Going Down" in particular clearly shows how well the DAC can integrate into the system and allow the lower registers to solidify the foundation. Thanks to properly addressed psychoacoustic phenomena, there is no frequency shelving in the upper mids and higher frequencies and the bass is also present and focused.

Pasithea eludes the coarse and crude momentum with the newfound emphasis on vitality. It not only drives the clear, prominent bass but also brims and fills the acoustical space with all instruments (and voice) radiating with analog-like resultative quality by channeling elementals or aural composition.

Sonnet Pasithea did not impose its rules on the listener, as too many DACs can do, but delivered a "Big Things Going Down" impressively vivid and non-fragmented. 


 "The Thrill Is Gone" by Barry Harris Trio & Roni Ben Hur from the album Backyard is an easy-to-recall memorabilia and factual track when it comes to pure tone, emotion, and harmonicity.

Again, the Sonnet Pasithea DACs have ensured that it's not just another pale-sounding digital-to-analog converter, nor is it a faux transparent (entering the realms of brittleness), but a neutral, vibrant, and involving one, as it should be.

Every single key element that defines the context and framework of "The Thrill Is Gone" was reproduced with impressive details, providing the necessary golden unity of timbre and tone color, as well as a surprising density of sound localization at a high level and dynamic intensities.

Another big plus for Pasithea was the way the instruments fit together in the listening sphere. 


"It's on"  is one of my favorites tracks from the album After Hours by George Duke. This fantastic track with so many layers of music presented with a rare forte matter-of-factness and emotional outbursts at their finest.

A mediocre DAC may reproduce some of the magic, but a good-sounding and efficacious DAC will reproduce "It's on" with an unmistakable mojo that should keep your full attention on the music.

Many DACs hold back from reproducing "It's on" in its entirety because they have a kind of black hole-absorbing effect that not only soaks up the energy with a bell-shaped curve effect but also blurs the upper frequencies and deforms the leading edges of the notes.

Pasithea takes the lore of "It's on" to a new plane, manifesting the track, not as a sum of many parts, but as wholeness, validly echoing all instruments with their clear physical space, proper spatiality, and distinctive harmonic richness.

From track to track, Pasithea brings to life the warm soul of After Hours, without touching and changing the intimacy and without shaking the great given togetherness.


​Sonnet Pasithea's ability to grow in intensity and depth without restriction was further confirmed with Grace Davidson's album Sacred Chants.

It was quite impressive how Pasithea DAC managed to layer sounds when the notes overlapped and the narrative became convoluted.

The character of Grace Davidson's voice comes through with all its silkiness and blends into the fabric of the music with surprising ease, which is not to be expected at this price.

The Pasithea DAC has a unique ability to handle the dichotomy of sublimeness and dynamism, impressive to say the least. 


It was immediately apparent how Edward Grieg Peer Gynt Suite No. 1 Op. 46: Anitras Tanz · Academy of St. Martin in the Fields did not suppress subtleties and escaped the hubris of over-illuminating musical artifice.

Tempo choices were conjured with the requisite elasticity, deftly swinging the narrative back and forth and variegated with dynamic authority.

Pasithea DAC portrays the beauty of the orchestra with lifelike physical characteristics and behaviors without temporal discontinuity.

Although transparent at its core, Pasithea engendered a warm, realistic atmosphere, with splattery highs with natural luster and shimmer.

Pasithea also presented a different kind of minutiae that I would have expected at this price, along with a first-rate, zoomed-out look at the musical momentum going on beneath the grooves, never lacking in ambient vibes and granting an above-common amount of acoustic cues. 

Conclusion


The quality of digital audio files has soared and improved greatly in the last few years and Sonnet Audio didn't sleep on its laurels. 

With knowledge distilled from the past and the latest developments, research, and technological advances, the way has been paved for Pasithea.

The Sonnet Audio Morpheus was already a high-potential DAC and offered some of the best value, especially for its money. The Pasithea brings everything even further.

The new modules, the new power supply, and the new findings have given a real boost to the Sonnet flagship DAC, where the moments and movements of the music evolve even more competently and to the point.


The Sonnet Pasithea can more accurately represent various contrasts of timbres, tones, and colors of music.

It also better reproduces both individual elements and the harmonic wholeness of music without the need to use imagination to fill in the gaps between missing attributes, as is often the case with more affordable and some even equally or more expensive DACs. That alone is a virtue that makes it a genuine stand-out. 

Sonnet Pasithea is among those DACs that reproduce music with sheer confidence. And that is reflected in the pure music reproduction and performance. It escapes the trap of many so-called forward-thinking and up-to-date contemporary DACs that can all too easily deliver a contentless presentation. 


Without establishing the essence of the music and creating a distortion-free environment, a DAC simply cannot translate musical forces into reality. Among many things, failure to deliver the right phase and timing affects echolocation and our perception and awareness of the music and this is something that is due to many facts too many times neglected or simply not addressed. 

Sonnet Audio Pasithea DAC captivates with a quality where sound and music are not frantically cobbled together, but an actual act of sonic cohesion where quiet and loud passages complement each other like yin and yang, and the enormity of the music unfolds compelling qualities.

The essence of the music's physicality is presented straightforwardly with a kind of genial presence, an abundance of detail, and a sonic dynamism in which the sound becomes an elemental, balanced blend. The Pasithea narrows the relationship between music and sound, creating a seamless connection that promotes intimacy without interruption.

With the Sonnet Pasithea, the power of minimalism is so skillfully realized that the complex electrical engineering is reflected in a simple, straightforward soundscape where the DAC can express refined musical details and has the unique ability to engage the listener with far more indulgence than might be expected at its price point. 


I coudl dwelled deeper into the music than I did with Morpheus. With some of the self-composed and mixed electronic music, I could feel the immediate sense of analog rawness that emanates from the analog synthesizers, drum machines, and mixers, which I treasure so much. There is something instantly captivating and tactile about the sonic potency of Pasithea DAC. 

The top-of-the-line Sonnet Audio DAC provides access to the essence of music in a relatively small size and at a more than reasonable price, moving from the fringes of DAC manufacturing to the mainstream. Once again, Sonnet Audio's meticulous work shines, easily surpassing the ineptitude exhibited not only by entry-level DACs but also by some more expensive ones. 

Pasithea decodes the enchanting beauty of music with a unique ability to eloquently convey the message without altering the appeal or allure by creating a relaxing aural habitat where you do not want to interrupt your listening pleasure. 

Once again, Cees and his team have hit the mark with performance and price. Pasithea feels twofold compared to Morpheus, further exploring the already extended boundaries with a uniquely vital verve and decisive livelie. 


For what it represents musically and sonically, I wholeheartedly award the Sonnet Digital Audio Pasithea DAC the 2023 Mono & Stereo Upper Echelon Product Award. •

Matej Isak

Price

  • Consumer price in Europe Euro 5900 21% VAT included
  • Consumer price rest of the world Euro 4876

Technical Specifications

  • Balanced  Non oversampling DAC
  • Four SDA-3dac modules per channel in differential mode
  • Power supply 30VA  110/115V AC 220/230V AC 60/50Hz. Power required max 16 Watts
  • Input 1x optical, 1x coaxial and 1x  AES/EBU, 1x I2S and 1x USB input.
  • Output 1x stereo pair single ended  2 Volts RMS. In -10dB mode 0.66 Volts RMS
  • Output 1x stereo pair XLR balanced 4 Volts RMS In -10dB mode 1.33 Volts RMS
  • Frequency Response 44.1 kHz sampling 1Hz – 20 khz -1dB
  • Frequency Response 192 kHz sampling 1Hz – 65 kHz – 3dB  and 384kHz (Windows only)
  • Distortion 0.001% THD
  • Channel separation 125dB
  • Noise Floor -160 dB related to 4 Volt RMS
  • Output impedance RCA 100 Ohm, XLR 16 Ohms, Physical -10dB setting 8 Ohms
  • Sampling rate Optical 44.1 – 96 kHz
  • Sampling rate Coax and AES/EBU: 44.1 -192 kHz
  • Sampling rate USB 44.1 – 384kHz
  • Dimensions 290 x 250 x 60 mm
  • Weight 3.5KG
  • Aluminum six button remote control included.
  • Dimensions 290 x 250 x 60 mm
  • Weight 3.5KG
For MQA or I2S more information can be found here

Contact


Sonnet Digital Audio BV
Daviottenweg 9-11,
5222 BH 's-Hertogenbosch
The Netherland

Phone sales office:  +31(0)36-7856259
Email: info@sonnet-audio.com