AAC is one of the most commonly-supported Bluetooth codecs in the wireless headphone and speaker markets. It’s also the default audio compression codec used by Apple’s iTunes and YouTube, and is supported across both iPhone and Android smartphones.

Active Noise Cancellation (ANC) reduces unwanted sound by the addition of a second sound wave specifically designed to cancel out the first. This basically results in no sound at all as it reaches unwanted sound even at the lowest frequencies.

Passive noise cancellation is done by means of insulating filters and works best on the middle to high frequencies. It does not work on the lower frequencies meaning that some sound can still be heard.

So, what's the difference?

Active speakers have an in-built power amplifier and just need a power cable (or battery) to operate. Passive speakers require an external power amplifier to operate.

In short, you need an amplifier for passive speakers, you don't with active speakers.

Apple AirPlay is found on all Apple devices. It lets you share videos, photos, music, and more from Apple devices to your Apple TV, favorite speakers, and some smart TVs.

The AKG K-1000 headphone has been around since about 1990. It is extremely high performance. AKG described it as an "ear speaker".

Some say that it feels like you can reach out and touch the sound they produce, such is their visceral quality.

Most modern systems use Digital Signal Processing. DSP samples analogue soundwaves into a limited set of numbers and records them. The overuse of DSP can result in an overcompressed unnatural sound and the translation and reassembly of data make digital devices prone to loss of quality.

All iFi products use Analogue Signal Processing as we believe it is better suited to audio. ASP does not cause signal quality to be lost as it records waveforms as they are and produces a more natural sound. 

For cost and convenience, modern DAC chips have a built-in digital volume control. The drawback is that a digital volume control works by 'truncating' the signal. Or 'chopping Bits' of resolution. For a 16-Bit music file at 50% volume level means the listener is actually listening to 14.5-Bits!

All iFi products bypass the digital volume control and use a separate analogue volume control which does not 'lose Bits' so a 16-Bit file stays unchanged which delivers maximum resolution.

Losing Bits of resolution (quality) is like having missing pixels on a computer or TV screen.

So, why don't we provide these two cables with our products?

The Apple CCK cable can only be purchased from Apple. We can't make one ourselves as it has a special chip in the cable that we'd need to use for them to actually work with Apple hardware. Sadly, Apple has not released this chip to anyone. 

We can and do make two versions of an Android OTG cable - Type C and micro.

aptX Bluetooth transmission is found in most Android phones, media players, Apple computers (macOS on iMacs and MacBooks) and on higher-quality Bluetooth headphones. It is not available on iOS (iPhones and iPads use Advanced Audio Codec).

aptX™ Low Latency audio ensures your Bluetooth® wireless enabled device can deliver sound in sync with visual media. It reduces delay and improves end-to-end speed of the audio transmission, resulting in a high-quality, synchronised user experience.

With aptX™ Low Latency you can enjoy the freedom of wireless for applications such as gaming and watching videos.

Most modern systems use DSP - Digital Signal Processing.

DSP samples analogue soundwaves into a limited set of numbers and records them. The overuse of DSP can result in an overcompressed unnatural sound and the translation and reassembly of data make digital devices prone to loss of quality.

All iFi products use Analogue Signal Processing as we believe it is better suited to audio. ASP does not cause signal quality to be lost as it records waveforms as they are and produces a more natural sound.

This is a type of audio circuitry topology that uses individual left & right channels.

It is a superior method to the single-ended circuit approach. Balanced circuits reduce noise and crosstalk.

While single-ended is used by most at this price level, iFi is implementing balanced circuits across the Zen range which is quite a step-up.

This is a type of audio circuitry topology that uses individual left & right channels.

It is a superior method to the single-ended circuit approach. Balanced circuits reduce noise and crosstalk. Less Interefence - clearer sound.

You normally find this set-up in products at the higher end of the spectrum such as the Pro iCAN but iFi is now using it across its product ranges to produce interference free audio.

Let's talk headphone cables.

An unbalanced headphone cable has a left + and right + wire, for each respective side. The other, the third - wire is shared by both left & right channels. As this is shared, this gives rise to undesired coupling noise which is commonly referred to as 'crosstalk.'

A balanced cable has the same left + and right +. But it has a separate left - and right -. With totally separate wiring 'crosstalk' is negligible.

Therefore, a balanced connection is the superior headphone wiring configuration.

In digital audio, a value called bit depth describes the resolution of the sound data that is captured and stored in an audio file. A higher audio bit depth indicates a more detailed sound recording.

So, the higher the bit depth, the higher the quality of the audio. Bit depth is usually 16 bits on a CD and 24 bits on a DVD.

If you 'lose' bits, the quality of your music will deteriorate.

If a file is "Bit Perfect' it means it has stayed the same. For example, if a PCM file is played through a DAC to improve the sound quality and the DAC does not change the file format. The file is 'Bit Perfect'.

This is the latest version of the Bluetooth wireless commnunication standard.

Its main benefits are improved speed and greater range - it's faster and can operate over greater distances than older versions of Bluetooth. You can find out more here.

A busbar is simply a conductor through which current flows.

A CD transport concentrates on reading the information held on a compact disc without expending effort in turning that digital signal into an analogue output, unlike a CD player. All you need to do is add an external DAC.

A class-D amplifier or switching amplifier is an electronic amplifier in which the amplifying devices operate as electronic switches, and not as linear gain devices as in other amplifiers. Just like SMPS (Switch Mode Power Supplies), standard Class D amplifiers have an inherent noise issue due to their 'switching' nature.

The common noise filter cuts out most noise gremlins found in typical audio systems such as RFI/EMI.

DACs convert digital information, stored or streamed by computers, into music we can hear through speakers or headphones.

Every device that's a source of digital sound has a built-in DAC (TVs, games consoles, CD players, phones, portable music players etc). Dedicated external DACs sound much better than standard DACs used in digital devices such as phones.

A DAP is a device like an iPod or an MP3 player that stores and/or plays back music digitally.

A digital audio workstation (DAW) is an electronic device or application used for recording, editing and producing audio files. It's basically a mixing desk.

Dolby digital is one of the most popular formats for surround sound. It's used by DVD's and Netflix.

It is a compressed format, so the newer uncompressed formats sound better.

The DoP protocol is a method for transferring DSD Audio over PCM. DoP simply uses PCM frames as a carrier for the native DSD data. A DSD stream can be carried over a lower data stream and will be completely unchanged at the end of the process.

DSD is a very high-quality digital audio format that's even better than CD quality. The higher the 'DSD rate' – DSD64, 128, 256, 512 and 1024 - the greater the amount of music information available, which means better sound quality.

Files can be remastered to higher file rates to improve sound quality. The pinnacle of this is DSD1024. Not many machines out there are capable of this feat.

Digital signal processing (DSP) is the use of digital processing, such as by computers or more specialized digital signal processors, to perform a wide variety of signal processing operations. When it comes to audio the overuse of DSP can result in an over-compressed, unnatural sound.

DTS is a company that licences codecs. They dominate the physical disc market with DTS5.1 and DTS Master Audio.

Electrostatic headphones work completely differently than conventional "dynamic" or "moving coil" headphones.

Dynamic headphones have a coil of wire inside a magnet. This wire coil is glued to a stiff cone that's held in place with springy suspension. Current passes through this coil and electromagnetism creates force on the coil while in the field of the magnet. The resulting force vibrates the coil which, as it is glued to to a heavy cone, moves the entire set-up in and out and creates sound.

Electrostatics place a non-moving static electric charge on an ultra thin film that floats between two metal plates. When audio voltages are applied across the plates, static cling and repulsion cause the film to move by itself. There is no contact.

This process requires very high voltages and special amplifiers to drive them which is where the Pro iESL comes in.

EMI is a type of interference caused by errant and unwanted electromagnetic waves that are received and amplified by an audio system. They cause some of the annoying 'audio gremlins' we often talk about.

MP3 – this is the most popular format, every device in the world can use it.

DSD – Direct Stream Digital is a very high-quality audio format, better than CD quality. The higher the number (sample rate), the better the recording - DSD64, 128, 256, 512 and 1024.

PCM - Pulse Code Modulation is the most common format for CDs and DVDs.

DXD - Digital eXtreme Definition is a very high-quality PCM format. It was developed to edit hi-res (high quality) recordings recorded in DSD.

Filters are used in music to alter the harmonic content of a signal, which changes its timbre or sound.

Just as using a coloured filter on a camera lens will alter the look of the resulting photograph to set the right mood, filters work in a similar way in audio.

Gain is the amount of increase in audio signal strength. Gain is often expressed in decibels (dB).

Galvanic isolation is a design technique that separates electrical circuits to eliminate stray currents that contain noise. Signals can pass between galvanically isolated circuits, but stray currents, such as differences in ground potential or currents induced by AC power, do not pass. This means little or no noise interference to the audio signal from stray currents.

In an electrical system, a Ground or Earth loop occurs when two points of an audio system both have a ground reference which causes a 'potential voltage difference' between them. Ground loops are a major cause of the noise, hum, and interference in audio, video, and computer systems.

HWA is Bluetooth® wireless audio powered by LHDC™ and used by Huawei.

LHDC™ is codec developed by Savitech and stands for 'low latency and high definition' audio. Compared to standard Bluetooth®, it allows 3 times more musical date to be transmitted.

IEMs stands for In-Ear Monitors.

These fit inside your ear. You've been using them for years. You just called them something else.

You will also see these referred to as earphones, ear buds and CIEMs. CIEMs are Custom In-Ear Monitors - IEMs made specifically to fit your ear shape.

When you see the Japan Audio Society (JAS) Hi-Res logo on a product it means that has this certification and conforms to the high standards for high resolution music put in place by the JAS consortium – to which the largest global electronics manufacturers and the biggest music labels have all subscribed.

Founded way back in 1958, Koss now produce a wide range of headphones to cater for varying tastes. One of their most acclaimed creations is the ESP950, over electrostatic ear headphones which retailed at about $999.

LDAC is an audio coding technology developed by Sony, which allows streaming audio over Bluetooth connections up to 990 kbit/s at 24 bit/96 kHz (also called high-resolution audio).

It is used in Sony headphones, smartphones, portable media players, active speakers and home theaters.

LDAC is a lossy codec which means is disgards some of musical info to make the file smaller.

A linear power supply design applies the AC line voltage to a power transformer to raise or lower the voltage before being applied to the regulator circuitry. They have very little output noise.

Lossless and lossy compression are terms that describe whether or not, in the compression of a file, all original data can be recovered when the file is uncompressed.

With lossless compression, every single bit of data that was originally in the file remains after the file is uncompressed.

On the other hand, lossy compression reduces a file by permanently eliminating certain information. Lossy audio files do not retain the natural authenticity of the original.

MQA is an award-winning British technology that delivers the sound of the original master recording. The master MQA file is fully authenticated and is small enough to stream or download. More here.

Network-attached storage (NAS) is dedicated file storage that enables multiple users and client devices to retrieve data from centralized disk capacity.

Users on a local area network (LAN) access the shared storage via a standard Ethernet connection. NAS devices typically do not have a keyboard or display and are configured and managed with an app.

Native playback simply means that the file format has not been changed.

You wanted to listen in PCM, you'll still be listening in PCM. The DAC does not change the format of the original file.

Reference to the 1984 film Ghostbusters. Four guys, a girl and ghosts. And proton guns that would destroy the world if you crossed the streams. Watch this.

Omotesandō is known as one of the foremost 'architectural showcase' streets in the world, featuring a multitude of fashion flagship stores within a short distance of each other.

These include the Louis Vuitton store (Jun Aoki, 2002), Tod's (Toyo Ito, 2004), Dior (SANAA, 2004), Omotesandō Hills (Tadao Ando, 2005) and Gyre (MVRDV, 2007), amongst others. More here.

The Sennheiser Orpheus HE90 are legendary headphones created in 1991 and limited to 300 pairs. They came with their very own valve amp and cost $16,000. Phew!

In simple terms, polarity refers to the way a signal flows.

Audio signals generally flow one way, like DC current, and have positive polarity. Inverting the polarity can have a negative impact on sound and equipment.

A 'load' refers to a current drain that is applied to a battery. For example, charging the flash in a camera. The term 'Pulse Load' indicates that the load is automatically applied for a specific period of time, then disconnected without user intervention.

Radio-frequency interference (RFI) is very similar to electromagnetic interference (EMI) but is found in the radio frequency spectrum. It is another source of irritatiing, unwanted noise often talked about as an 'audio gremlin'.

Top tip: just don't add water.

Shigeru Ban (坂 茂 Ban Shigeru, born 5 August 1957) is a Japanese architect, known for his innovative work with paper, particularly recycled cardboard tubes used to quickly and efficiently house disaster victims.

He was profiled by Time magazine in their projection of 21st-century innovators in the field of architecture and design. Find out more here.

A switched-mode power supply is an electronic power supply that incorporates a switching regulator to convert electrical power efficiently. It transfers power from a DC or AC source to DC loads, such as a personal computer, while converting voltage and current characteristics.

Switch-mode power supplies are widely used because of the advantages they offer in terms of size, weight, cost, efficiency and overall performance. They are in themselves noisy and were not designed with audio in mind.

A solid-state amplifier uses electronics such as diodes and transistors to amplify the music signal. A tube amp uses valves/vacuum tubes to do the same job.

There is a noticeable sound difference between the two methods. Some feel that tube amps create a warmer, more musical tone. Some companies choose to build 'hybrid' models that combine the two methods.

So, what is soundstage?

Imagine yourself in a small theater, 10 rows from the front, dead center, watching an orchestra perform on stage. Now close your eyes. This is the 'sound stage'.

In audio speak, it is an imaginary 3D space created by the high-quality reproduction of sound in a stereo speaker system. In other words, the soundstage allows the listener to hear the placement of the orchestra vis-a-vis instruments when listening to a given piece of music.

Spotify Premium allows you to listen better quality music. It's all about bitrates. The bitrate is the amount of data processed over a certain amount of time. The higher the bitrate, the better the quality.

On normal Spotify you listen at 96kbps, the 'standard' bitrate on mobile or at 160kbps, 'standard quality' on desktop and 'high quality' on mobile.

With Spotify Premium, you get 320kbps which is 'high quality' on desktop and 'extreme quality' on mobile. Basically, more bitrates for your buck.

The square wave pattern is what is desired in audio. It contain more harmonic content than a sine wave or a wave full of distortion and jitter.

Tadao Ando (安藤 忠雄 Andō Tadao, born 13 September 1941) is a Japanese self-taught architect whose approach to architecture and landscape was categorized by architectural historian Francesco Dal Co as "critical regionalism".

Read more here.

Tidal is a subscription-based audio streaming platform, similar to Apple Music and Spotify, but with lossless-quality audio. Tidal Masters is the section with the highest-fidelity music streamed including some files in partnership with MQA.

Lossless-quality means that no music quality is lost in this format.

USB audio is a digital audio connection used to send digital music from your computer to a digital to analogue converter (DAC). Usually computer manufacturers spend most of the overall budget on the processors and screen, leaving minimal budget for the built-in DAC and audio outputs.

The USB protocol is outlined in a technical paper onthe usb.org website.

We have pored over this paper to ensure that we have closely followed the tight tolerances/specifications. For example, a major specification is adhering to 90ohms impedance.

All iFi cables have been designed with this in mind.

In electronics, volumetric efficiency quantifies the performance of some electronic function per unit volume, usually in as small a space as possible.

Zen emphasizes rigorous self-control, meditation-practice, insight into the nature of things and the personal expression of this insight in daily life, especially for the benefit of others. Discover more here.