Desk Assault
Ratings
Pros
- Sound quality.
- Compact design.
- Informative display.
- Volume control.
- Power level.
- Bluetooth 5.2 with the best formats.
- Does not heat up.
- Great value for money.
- Powered by USB 5V charger.
Cons
- Design more functional than beautiful.
- Questionable bass boost.
Purchase Link
https://es.aliexpress.com/item/1005005324896514.html
Link to the Store
Introduction
Tempotec continues to be one of the most prolific brands when it comes to dongles. This time, however, it has gone one step further and created a small but versatile desktop DAC/AMP with a built-in Bluetooth 5.2 receiver. It has two audio outputs, 3.5mm SE and 4.4mm BAL, gain selector and bass boost. It is capable of decoding Bluetooth LDAC, AAC and SBC, native DSD up to 512, 32bit/768kHz PCM and performs x8 MQA unfolding. It has a small OLED display, step potentiometer, RCA line output and coaxial and optical digital inputs. As DAC it uses two AK4493SEQ and as amplifier 4 OPA1688. Finally, it uses a high-performance FPGA AP24390 digital circuit. Let’s see what else this small audio device, whose price is just over $100, has to offer.
Specifications
- DAC: AK4493SEQ.
- AMP: 4 OPA1688.
- FPGA: AP24390.
- Bluetooth 5.2 receiver, LDAC 990kbps, SBC 328kbps, AAC 256kbps formats.
- Native DSD up to 512
- PCM 32bit/768kHz.
- MQA x8
- MAC OS, Windows OS, Android OS and Linux OS supported.
- RCA LO parameters:
- Output voltage: 2VRMS.
- Frequency response: 0-60kHz.
- SNR: -119dB
- THD+N: 0.0006%
- Crosstalk: 113dB
- SPDIF Out parameters:
- Output voltage: 2VRMS.
- Frequency response: 0-80kHz.
- SNR: -140dB
- THD+N: 0.00008%
- Parameters Headphone output 4.4mm BAL:
- Output voltage: 4VRMS.
- Frequency response: 0-50kHz.
- SNR: -118dB
- THD+N: 0.0009%
- Crosstalk: 120dB
- Output power: 630mW/32Ω
- Output impedance: 0.3Ω
- Parameters Headphone output 3.5mm SE:
- Output voltage: 2VRMS.
- Frequency response: 0-50kHz.
- SNR: -116dB
- THD+N: 0.001%
- Crosstalk: 73dB
- Output power: 310mW/32Ω
- Output impedance: 0.3Ω
- Dimensions: 100x85x34mm
Packaging
The Temptec MARCH III comes in a plain black cardboard box, whose dimensions are 198x139x64mm. On the top side, in the centre, you can see the name of the product, in yellow capital letters. At the top left is the brand logo. At the bottom right are the DSD and MQA logos. On the back there are some icons with the product characteristics and the brand’s logo. The brand logo and the model are repeated on the sides. It opens from the top and the product is under a sheet of black foam, inside a protective mould of the same type, next to a dark box containing the USB cables. The complete contents are as follows:
- Tempotec MARCH III.
- Bluetooth antenna.
- 2 USB Type A to Type C cables.
- 1 USB charger Output 5V 2.0A. Input AC100-240V 50/60Hz 0.4A Max.
- 1 quick manual.
- 1 warranty card.
- 1 quality certificate.
The presentation is austere, the cardboard is robust, all the elements are very well protected. The fact that it comes with two USB cables and, above all, a USB charger is appreciated.
Construction and Design
It is a relatively small device, measuring 100x85x34mm, not counting the potentiometer, which is just over 10mm. The outer casing is metallic, perhaps some aluminium alloy, painted black, with a micro sandy texture. The edges are very rounded, which gives it a nice contour. The main face has two glazed parts, at the ends of the potentiometer. On the left side are the headphone outputs, 3.5mm SE and 4.4mm BAL. Above them you can read the product model. The potentiometer is in the centre, rough and ribbed, with a white circle around it and the text ON/OFF underneath. To the right is the OLED display and below it three buttons: MODE, GAIN and BASS. These buttons are not very uniform with each other, as they have a slight play that subtly misaligns them. On the back side, from left to right, you can see a Philips screw, the DC 5V USB Type C socket on the base and another USB Type C connector for the input connection. Above that is the connector for the Bluetooth antenna, which is threaded and gold-plated. Beyond the centre are the gold-plated RCA line outputs. There is an Allen screw in the centre, separating the digital outputs, above is the gold-plated coaxial output and the SPDIF optical output. Finally, on the far right, is the other Philips screw.
Underneath, at the base, it has two flat, elongated rubber strips, whose function is anti-slip.
The construction is good, somewhat simplistic, but effective. The design is relatively attractive. The black colour is nice, as is the gold around the headphone jacks. The potentiometer is a bit more controversial and together with the unevenness of the buttons may offer a more «cheap» look. The display is sufficient, quite clear and visible, which is appreciated.
Connectivity
The MARCH III is compatible, via USB, with Windows XP, Windows Vista, Windows 7, Windows 8, Windows 8.1, Windows 10, IOS, Android and OSX.
It has RCA line, coaxial digital and SPDIF digital outputs.
It is a Bluetooth 5.2 receiver, with a range of up to 30m and supports LDAC 990kbps, SBC 328kbps and AAC 256kbps formats.
It can play DSD natively up to 512, PCM 32bit/768kHz and can perform 8x MQA unfolding.
It has two headphone outputs, one 3.5mm SE and one balanced 4.4mm.
Operativity
The operation is very simple, the USB power supply is connected and the display lights up a little. By pressing the potentiometer, the device is switched on or off. I like the fact that the potentiometer goes in steps. Each step is strictly a volume step. There are 100 volume steps.
The Mode button toggles between USB DAC mode and Bluetooth receiver mode. When entering Bluetooth mode the M3 goes into pairing state and can be found as Tempotec M3. The display gives the mode information in the top left corner (USB/BT), while the top right corner specifies the decoded format or Bluetooth Codec used. The centre of the display shows the volume (VOL:). In the lower centre the word GAIN is displayed if the high gain mode is activated and in the lower right corner the word BASS is displayed if the bass boost mode is activated.
Measures
No Load SE
At low gain, the maximum output is close to 2V, while at high gain, the voltage is around 2.6V. I was expecting the gap between high and low gain to be larger, but I didn’t expect it to reach almost 2V at low gain.
15 Ω SE
For this impedance value 1.23V, a power of 100mW and 82mA are achieved. Quite good. Once the magic value of 90mA is confirmed.
33 Ω SE
2.08V for 33 Ω per SE is a great voltage, reaching 130mW of power and 63mA. But it doesn’t square with the specs, which say the power for this impedance is 310mW. Following Ohm’s law, this would imply 3.15V, which is not achievable even without a load. This is absurd.
100 Ω SE
At this impedance the maximum voltage value of 2.57V is achieved, which implies 66mW and 26mA. One thing that can be deduced from this value is that the output impedance is really low, you can verify that its value is 0.3 Ω.
No Load BAL
At low gain the maximum voltage value is 3.84V, while for high gain it is 5V. Very good.
15 Ω BAL
As expected, it is very difficult to beat the voltage for 15 Ω SE output, so the values are very similar: 1.3V, 110mW power and 87mA.
33 Ω BAL
2.6V, 200mW and 79mA, a not inconsiderable amount, far from the 630mW specification, which would imply a voltage of 4.5V and 140mA. Voltage-wise it would be possible, but current-wise it would not. No need to lie because 200mW is a great value.
100 Ω BAL
4.92V, 240mW and 50mA. It appears that the output impedance is somewhat higher per BAL than the specification, above 1Ω.
Frequency Response
The frequency response is completely flat from 5Hz to 40kHz and the difference between channels is zero, both responses are superimposed as if they were one.
On the other hand, the frequency response when the bass boost is activated is beyond me. As you can see in the graph, it is a boost of more than 10dB up to 400Hz. After that, it starts a slight linear decrease, crossing the standard FR at 3.5kHz, to lose 10dB at 10kHz and 15dB at 20kHz. I would understand, as bass boost, a 2 or 3dB boost, up to 200Hz. But what Tempotec has done goes beyond a simple bass boost.
Sound
Despite having a AK4493SEQ DAC, the sound profile is quite neutral and clean. I don’t find it to be distinctly warm, although the low end is well present. I have not used bass boost for this sound description, because I understand it is a gimmick for experimentation, rather than a hi-fi option, based on the purity of the sound.
The device used for comparison was the Burson Audio Playmate II.
The low end of the MARCH III is very compact and concise, feeling moderately fast and tight. As is usual with this kind of presentation, the roughness is relatively low and the texture smooth, not very descriptive. The bass has a slight colour and is not as sensory as in higher priced equipment. Thus, the lower range is refined, polite, restrained, but well-drawn and skilled. It has good resolution and technical ability to demonstrate its ability to cope with complex conditions, plus a little light and a lighter, not too heavy bass feel. Nor is it too dense, bulky, dark or deep.
To describe the mid-range we have to look at the specifications and say that it uses a AK4493SEQ DAC, known for its «Velvet Sound». It is worth noting that its sound is sharper than I expected and I don’t mean that in a pejorative sense. This DAC seems to have a more analytical sound than I might have thought and this is something I have found in, for example, the DAP V6, as opposed to devices using the ES9038 DAC, for example. The sound is refined enough for this price range, but, perhaps it lacks the smoothness and musicality of higher-end devices. But I am talking about devices 3 times the cost of the M3. So, comparatively speaking, it is a great value for money, with a fairly high level of accuracy, without sounding harsh. Perhaps it lacks some depth, density, volume and a more descriptive feel in the detail and texture of voices. But it is still a very full and natural sounding device in this mid-range. Vocals sound completely realistic and perhaps have a bit of a rough sparkle on uncontrolled recordings, something that can also happen with instrumentation.
It is in the treble representation that I recognise that AKM «Velvet Sound» the most. The extension is not as clear and bright, but feels slightly softened, to avoid a more crisp or sparkling expression. Treble tone feels at that more polite and effective point, not losing control, but avoiding the light, resolution and extension level of other bolder, more expressive devices in this department, as well as greater finesse and penetrating power. The level of resolution is very adequate in the first half, but is a little more condescending in the air area.
The scene is remarkable, feeling wide and airy. At the edge and in depth, the amount of detail is perceived quite adequately, but one misses a higher level of clarity, sharpness and more air. Again, the comparison is unfair to clearly higher priced devices. But, I’ve pushed the M3 to the max, trying to get the colours out of it, to realise that this is a $129 device, with a really high performance for the price. Back to the scene, the volume is remarkable, the difference with a more expensive device is in the expansion of this volume and in the space between elements, as well as in the darkness of the background. But the M3 does a great job in these respects, generating a natural image, with a good level of three-dimensionality and clear, well-drawn positioning, with no glitches or flares.
Turning to the level of detail and resolution, it is able to demonstrate micro nuances adequately and realistically, but without reaching a surgical analytical level. As I say, the limit is in the isolation of such detail from the rest of the music, its distance and separation. But it’s certainly brilliant for a device of this class.
Conclusion
It is undeniable that Tempotec knows how to make high-quality audio devices. The MARCH III is a relatively inexpensive, but very good sounding and versatile desktop device. It has enough power to be supplied by a 5V charger, and even offers this level of output per BAL.
The M3 is a small desktop ALL-in-One, explicit in its functions, which knows how to exploit the potential of its components to the full. It has pretty much everything you would expect for the price: powerful SE and BAL outputs, precise volume control, 2 gain levels, bass boost, a very descriptive and clear display, line and two digital outputs, not forgetting its Bluetooth 5.2 up to 30 metres range, capable of using the best formats such as LDAC 990kbps. Can anyone give more for that price in that size? It’s hard to say. But luckily, Tempotec has got us used to things like this. Very good.
Earphones and Sources Used During Analysis
- Letshuoer DZ4
- Hidizs MS3
- Kiwi Ears Quartet
- KiiBOOM Evoke
- KiiBOOM Allure
- NiceHCK F1
- Letshuoer S12 PRO
- Rose QT9 MK2s
- Yanyin Aladdin
- ISN H40
- Penon Globe
- OurArt QJ21
- Rose Martini
- Sunrise Dragon 2 Limited Edition (SWD2LE) 10th Anniversary