Sleek design, flexible usage, and excellent performance.
The Sonata E44 is one of several options in TempoTec’s Sonata line of headphone DAC/amplifiers. The E44 is a more powerful version of the Sonata E35 (3.5mm TRS output), aptly named as it features a 4.4mm TRRS balanced output jack, providing extra power to the headphones/earphones.
- Excellent build quality
- Extensive format capabilities
- Tiny and attractive form factor
- Ultra-low ‘almost black’ noise floor at any volume
- No onboard battery (low power consumption from the source device)
- Transparent power sufficient to properly drive most consumer and relatively efficient headphones and IEMs
- Excellent value for performance
- No additional controls other than volume
- Lack of any additional software/app support to customize sound or performance
- No lightning cable adapter for Apple/iOs users
- Fingerprints galore
- The USB-C metal sleeve needs to be better secured
If you made it this far, you likely know what this thing is. If not, let me explain… a DAC/amp dongle is a device that generates more clean power and sound than you might get from your phone or computer directly.
Do you need one? Maybe, or maybe not, as the answer depends on multiple factors. Follow along and your answer will become much clearer!
First Impressions
The E44 is a classy looking small device with excellent wires and fittings. Every part and piece feels premium. There are no loose parts inside or out and it appears to be well engineered and built.
Company Overview
Operating from Dongguan City in Guangdong Province, China, TempoTec Corp. was established more than 20 years ago by a multinational team of audiophiles and experts from China, Taiwan, Korea, and Germany.
Technical Specifications
- Form: Dongle/portable headphone DAC/amplifier
- DAC Chipset: Dual CS43131 from Cirrus Logic
- Connections:
- 4.4mm TRRS balanced output / USB Type-C To 4.4mm balanced cable connected with 8-core, single crystal copper silver-plated OCC (Ohno Continuous Cast) wires
- Performance: 4.4mm balanced output
- THD+N: 115 dB
- SNR: 130 dB
- Crosstalk: -127 dB
- Output Power: 175mW @ 32 ohms
- Output level: 4.0 Vrms
- Frequency Response, 0Hz – 40KHz: ±0.5 dB
- Sampling Rate
- O/S Compatibility: PC, MAC, and Android (supports OTG function), most devices with USB Type-C ports; compatible with Windows 7, 8, 10, and USB ASIO driver; plug and play
- On-device controls: hardware volume control (rocker switch) with 32 steps of volume scale
- Size: 185mm total length x 21mm x 7mm (7.28 x 0.83 x 0.28 inches)
- Weight: 27.2 grams (.96 ounces)
Packaging
Packaging is a clean and simple affair. An outer white thick paper wrapper surrounds a small, sturdy, black box with a magnetic closing flap. Open the box and you will find the E44 held safely in place in a hard foam block, cut to secure the parts exactly to form. Under the foam block are some additional accessories.
In the box
- TempoTec Sonata E44
- 1 female USB-C to male USB-A adapter
- 4.4mm male balanced to 3.5mm female cable adapter
- Two thin-film screen-type protectors for the E44 body
- Two wipes (1 dry, 1 wet)
- Small High-Res sticker
The E44 does not come with a USB-C to Lightning cable adapter for Apple/iOs devices.
Cable
The E44 has two attached flexible cables, the 4.4mm TRS output and the USB-C plug. The E44 uses 8-core, single crystal copper silver-plated OCC wires, an upgrade over the E35’s 4-core 6N single crystal copper wires. According to TempoTec, these are used to improve the transferring accuracy of the digital signal.
The cables are braided, soft, flexible, and attractive. They look almost exactly like a thinner version of the deluxe Litz monocrystalline silver-plated copper cable supplied with the FiiO FD5.
Design
The E44 is a small, simple, and attractive thin wafer design. The high-quality black metal case is attractive, with a low-profile rocker button on one side and a label on the rear. The silver cables are a striking contrast to the black body, and the black metal headphone jack is substantial. Given how sturdy every part of the E44 feels, it is still quite lightweight.
The E44’s single long rocker button has an excellent positive-click feel and controls a 32-step volume scale. The volume down button is just above the TempoTec logo and the volume up button is at the other end of the button.
The materials on the faceplate lend themselves to heavy fingerprinting and smudging – in case this is of any concern to you. They wipe off easily with any dry cloth, and can be lessened by installing the included thin film protectors.
The USB Type-C connector secures very well – maybe too much so. There is a plastic cable sleeve to secure it all, covered by a black metal sleeve. After my first attempt to remove the E44 from my computer, it pinched the sleeve hard to pull the cable out – safely and properly.
As the black sleeve pulled away and the plug did not come out, my heart skipped a beat. The good news is that the piece is decorative more than functional, and I subsequently super-glued it back on properly.
Internals
The E44 houses and employs dual CS43131 Cirrus Logic DAC chips.
Sonata E44 Performance and Sound
Regarding performance, I have three main priorities with DAC/amps:
- Clean power
- Low noise
- Low distortion
Power
The E44 produces a healthy amount of power for a dongle DAC/amp: 175 mW @ 32 ohm at 4.0 Vrms. With high sensitivity and extremely low crosstalk and distortion, this is a high performance unit for something so small and portable.
I tested the E44 with multiple sources and approximately a dozen headphones and IEMs. To name a representative few with highly variable impedance and sensitivity, these included:
| Headphone/IEM | Sensitivity (dB) | Impedance (ohms) |
|---|---|---|
| V-Moda Crossfade M-100 | 107 | 32 |
| Drop + HIFIMAN HE4XX Planar Magnetic Over-ear Open-back Headphones | 93 | 35 |
| Sennheiser HD58X Open Back Professional Jubilee Headphones | 104 | 150 |
| Beyerdynamic DT 990 Pro 250 Ohm Over-Ear Studio Headphones | 96 | 250 |
| FiiO FD5 IEMs | 109 | 32 |
| Shuoer EJ07M IEMs | 107 | 19 |
There is only a small amount of heat generated by the E44, and never any noticeable noise, even with sensitive IEMs (in-ear monitors). For almost all IEMs, the power is exponentially more than they will require (or your ears can safely hear). For most headphones, the E44 produces adequate power to drive them well.
So can the E44 drive full-size headphones with high impedance? I tested the Beyerdynamic 250 ohm DT990 to confirm that the answer is yes.
Let’s use an example of what the result is using the E44 to drive 300ohm headphones. If you are using the 4.4mm balanced output, the maximum power for your headphones will be 53.3mW (output voltage = 4Vrms, power = 4×4/300=0.0533W).
Noise
A critical test for me given my priorities above is to check for unwanted noise. I plug in the headphones/IEMs and turn the volume up on the original source to maximum (with no signal playing), followed by increasing the volume on the amplifier to maximum, and I listen for hiss or noise.
The result every time with any headphones or IEMs: to my ears, ZERO audible noise from the E44. Dark as a sealed lightless chamber.
Sound
Regarding the overall sound, the E44 is relatively transparent to my ears. What’s most important to discuss is how it differs from a source, particularly a phone or computer with a standard 3.5mm headphone jack. A few notable differences are significant.
First: no audible hiss, noise, or distortion. Second, and most obviously, is the large power difference.
I tested using the stellar Shouer EJ07M with its high-quality stock cable. With the lovely 32AWG 16 Core 21-wire Tripowin Jelly cable, complete with 4.4mm plug (which I highly recommend), the increased power results in far more volume potential, and a very slight difference in my perceived “fullness” of the sound. The same applies with the FiiO FD5.
Depending on the source and destination, is a discernible improvement of clarity in the midrange. When A/B testing between my computer’s onboard 3.5mm jack to the 4.4mm jack on the E44, it sounds as if all the clouds that hang over the midrange disappear.
Where to Buy
Conclusion
Let’s revisit the original question: do you need a portable DAC/amp dongle?
If you have a headphone DAC/amp or a dedicated DAP (digital audio player), you may need the E44 if your current devices are not equally ultra-portable or sufficiently powered.
If you have a higher end computer with advanced audio capabilities, the E44 may not necessarily be an upgrade, unless you are set on using the E44’s 4.4mm balanced connection. If your system has a dedicated sound card, or an external USB DAC/amp, such as the excellent Creative SoundBlaster X4, there is no need for the E44.
However, If you have an average laptop or computer with no advanced audio components, the E44 will be an inexpensive and significant upgrade.
This may likely be the only portable DAC/amp you will ever need.
Packing so much clean power into something so small is quite amazing. The performance from the E44 is clearly far greater than what most phones and computers can offer. If your sounds matter to you, you will enjoy great returns on your investment.
The simplicity of the E44 combined with its performance prowess make this DAC/amp dongle an easy recommendation for a highly portable solution. The Sonata E44 will continue to be an on-the-go travel partner for me and my music!