Alpha & Delta D6 review

Alpha & Delta D6; Jazz sounds now better than before  


1. Introduction:

Alpha & Delta is a Singapore based brand that was founded of audiophiles with experience in the earphones retail industry. The D6 is the latest model of this company and there are also some few other models like AD01, D3, JAAP (wireless model) etc. that targets different users.


2. Disclaimer:

I would like to thank Alpha & Delta for providing me the Alpha & Delta D6 as a free of charge review sample. I am not affiliated with Alpha & Delta beyond this review and these words reflect my true, unaltered, opinions about the product.


3. Price & Warranty:

The MSRP price for the Alpha & Delta D6 is 95.00 USD and has a 3 Years Warranty.

Purchase Link:


4. Package and Accessories:

The Alpha & Delta D6 comes in a black card box with a transparent plastic front cover.

This box includes the following contents;

  • 1 x pair of ear guides
  • 1 x shirt clip
  • 1 x pair of foam tips
  • 9 x pairs of silicon ear tips
  • 1 x leather case
  • 1 x leather cable wrap

The silicone ear tips included in the box are comfortable and the foam tips are a nice addition.

The box includes a leather wrap and leather case that are looking very nice and are quite useful. There is also 1 pair of Ear-Guide and a shirt clip that is also a nice addition.

5. Design, Build Quality and Fit:

The Alpha & Delta D6 is a very well made IEM with a bullet-style metal shell, which has a glossy gunmetal painting. At the back of the monitor are the AD (Alpha & Delta) logo and the HDSS (High Definition Sound Technology) printing. On the top and on the nozzle are two holes that serve as bass vent. The nozzle of the monitor is not angled and has a fine black filter.

The D6 is lightweight, fits comfortably in my ear and has an above average isolation.

The Alpha & Delta D6 has a non-detachable cable, which in my opinion one of the best in the market, especially for a IEM with a price of 95 USD. Alpha & Delta decided to use a wonderful looking 8 core Silver Plated Copper (SPC) cable, instead of a regular 4 core design. This ensures, according to Alpha & Delta, that the earphone continues to work, even if one of the cables breaks.


The D6 is reinforced at the y-split and at the earphone’s housing. Moreover, the vulnerable 3.5mm jack is protected by a spring to ensure it can withstand any impact.

6. Specifications:

  • Driver Unit                  : 10mm dynamic driver
  • Impedance                 : 16 ohm
  • Rated power               : 1mW
  • Frequency Response : 10 Hz- 40 Khz
  • Sensitivity                   : 105 +/- db/ mW
  • Cable                          : 1.2m silver plated copper cable (each core contains 22X 0.05 silver plated copper wires)
  • Plug                            : 3.5mm Gold Plated Plug


a. About HDSS High Definition Sound Technology:

Speakers create sound through vibration. Due to the small enclosure, the reflected sound waves can distort our music by interfering with the sound waves entering our ears. HDSS technology removes these reflected waves to ensure crystal clear sound. The removal of reflected waves also allows speakers to disperse sound coherently, allowing for a naturally projected sound stage.

b. About Dual Chamber Acoustic Design:

The dual chamber acoustic design redirects reflected sound waves into a uniquely designed second chamber which absorbs these sound waves. This reduces distortion and improves the clarity and soundstage of the earphones.


7. Albums & tracks used for this review:

  • Saskia Bruin – The Look of Love (DSF)
  • Diana Krall – So Wonderful (DSF)
  • Aretha Franklin – I Say a Little Prayer (Apple Music)
  • Melody Gardot – Who Will Comfort Me (Flac 16bit/44kHz)
  • LP (Laura Pergolizzi) – Lost On You “Live at Harvard and Stone” (Tidal Hi-Fi)
  • Mile Davis – Kind of Blue Album (Tidal Hi-fi)
  • George Michael – Older Album (Apple Music)
  • Dire Straits – Money For Nothing (DSF)
  • Emmanuel Pahud (Claude Debussy) – Syrinx (Apple Music)
  • Otto Liebert & Luna Negra – Up Close “Album” (DSF) – Binaural Recording
  • Alboran Trio – Autumn Mist (Tidal Hi-Fi)
  • GoGo Penguin – Fanfares (Tidal Hi-Fi)
  • Opeth – Damnation (Tidal Hi-Fi)
  • Megadeth – Sweating Bullets (Flac 16bit/44kHz)
  • Daft Punk – Get Lucky (Flac 24bit/192kHz)
  • Future Heroes – Another World (Tidal Hi-fi)
  • Michael Jackson – Billie Jean (DSF)


8. Sources used for this review:

  • IEM                 : Alpha&Delta D6, Pinnacle P2, TFZ Series 4, Whizzer A15 Pro (Haydn)
  • DAP/DAC      : Cayin N5II, HiBy R6, Chord Mojo, Audirect Whistle


9. The Sound:

I am of the sort of people that believes in burn-in and this review is written after 100 hours. I have used the stock silicone ear tips (soft ones) that are included to the package.


I was very surprised when I heard the Alpha & Delta D6 for the first time, because it was not a typical fun sounding IEM like many others in this price range. The D6 has a fairly neutral tuning with a tonality that is slightly on the thinner and colder side.


The Alpha & Delta D6 sound very controlled at the sub-bass department. It doesn’t reach to the lowest register but has otherwise a pretty good clarity and extension.

There is missing some body in the bass department between 50 – 120 kHz that gives normally warmth and fullness to the sound. Especial electronic music types such as trance, edm, etc. which are mostly based on artificially generated sounds are particularly affected by this tuning. But luckily, the D6 responds very well to equalizing and you can boost it anytime.

The bass characteristic is suitable for classic, jazz, acoustic songs with live recorded instruments.

The midrange of the D6 is impressive with its high level of clarity. I didn’t expect such a detail level and crispness form an IEM in this price league. It sounds smooth, detailed and well placed and the separation of instruments is in a very good level.

I have tested some songs with complex instrument passages like GoGo Penguin’s – Fanfares where are many instrument playing at the background at the same time and the Alpha & Delta D6 sounded pretty controlled.

Both male vocals sounding quite realistic, but what really shines are female vocals like Melody Gardot and Laura Pergolizzi that are sounding clean and crisp with the D6.

There was a bit stress in the upper midrange at the very beginning, but after some burn-in and right tips selection, it was almost gone.

The treble range of the Alpha &Delta D6 sounds clear, crisp and well extended, without to be affected by sibilance. This was not the case at the very beginning; there was some sibilance for the first 10-15 hours that has gone after the next 50 hours.

Notes are precise and accurate and the overall tonal balance is well done. Genres like classic, jazz, acoustic are sounding very life like and precise. The D6 did a good job while presenting Alboran Trio’s – Autumn Mist that sounded very accurate and lifelike.

Soundstage and Imaging:

One of the strengths of the Alpha&Delta D6 is the soundstage presentation, which sounds wide and fairly deep, that has also an excellent imaging and instrument placement for this price category.


10. Comparison:

Vs. Mee Audio Pinnacle P2:

The Pinnacle P2 has a V-shaped sound signature with a consumer friendly tuning. The Alpha&Delta D6 on the other hand has a quite analytic sound tuning, which is suitable for critical listening.

The Pinnacle P2 has more sub-bass; especially bass quantity between 50 – 120 kHz, but is missing some definition. The Pinnacle P2 has the same amount of mid-bass impact with nearly the same resolution that the D6 has.

The midrange on the D6 sounds clearer and airier compared to the warmer and fuller tuning of the Pinnacle P2. Both IEM’s have a nice instrument presentation while the Pinnacle P2 is missing some speed in passages with high instrument density. Male and female vocals sounding a bit more natural and crisp due the brighter tuning of the Alpha&Delta D6.

The Alpha&Delta D6 is a treble centric IEM, which sounds overall brighter with more sparkle and air on the top end. The treble and upper treble area of the Pinnacle P2 has a more even tuning, which results to a more balanced presentation. The Alpha&Delta D6 has slightly more detail retrieval and sounds also more refined.

The Pinnacle P2 does its job in terms of soundstage, but the Alpha&Delta D6 is a step forward and has a wider and deeper soundstage presentation, where instruments have more space in complex passages. The Alpha&Delta D6 sounds also more precise in imaging and instrument placement.


Vs. TFZ Series 4:

The TFZ Series 4 has the same V shaped sound tuning like the Pinnacle P2 with a overall warmer sound tuning with higher bass presence. The D6 in the other hand is a treble centric IEM with an analytical tuning.

The TFZ Series 4 has a nice bass presentation in the subbass and bass department with a pretty nice impact that makes it too a better option for electronic music genres like techno, trance and edm. The D6 on the other hand has the better bass extension, speed and definition that make it very suitable for live recorded songs like jazz, blues, acoustic genres.

Both male and female vocals sounding fuller with the TFZ Series 4, but Alpha&Delta D6 has additional sparkle and transparency in the midrange department, which makes the listening of female vocals like Laura Pergolizzi and Saskia Bruin more exiting. The instrument reproduction of both IEM’s is quite good, but some string instruments like guitars have a more lifelike presentation with the D6.

TFZ Series 4 sounds pretty good in the treble range with its soft and non aggressive tuning. The Alpha & Delta D6 has additional sparkle and extension in the treble department with overall extra resolution. The upper treble range of the TFZ Series 4 is well controlled but is missing some fine definition compared to the D6.

TFZ and Alpha&Delta are nearly similar in soundstage performance but the D6 has additional wideness with better overall imaging and instrument separation.


11. Conclusion:

The Alpha & Delta D6 is an IEM that is focusing on clarity and soundstage with its treble centric presentation that is wonderful done. It has also a solid build quality with a great accessories package that makes the Alpha & Delta D6 worth’s every penny.


12. Summary (plus and minus):

+ Crystal Clear Sound

+ Airy Presentation

+ Build quality

+ Great Cable


– No detachable cable

– Missing some bass between 50-120 kHz


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1 Response

  1. An excellent review as always . Thanks for detailed review dear expert audiophile and reviewer Moonstar 👍🙏

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