Marshall, the company best know for its amplifiers and headphones, has launched its first ever smartphone, called the London, with a strong focus on sound quality.

The Android device claims to be the "loudest mobile phone on Earth" with two front-facing speakers and a dedicated hifi-grade sound card, allowing users to listen to music without the use of headphones.

It has two stereo jacks, each with their own independent volume control, so users can plug in two sets of headphones and share music or watch a video with a friend.

The London has a button on the top, called the "M-Button", which provides one-click access to the user's music, whatever the source of it may be. This includes the London’s pre-installed music player, which supports popular formats such as mp3, mp4 and AAC.

It has a scroll wheel on the side for volume control and a global equalizer, which allows the user to set a sound profile for all the music played on the phone without having to adjust each individual music app.

The phone can also be used to record music on the go. It comes with noise reduction software and dual microphones for recording in stereo. It also has a pre-installed DJ app, allowing users to mix their own tunes.

"We always aim to go big. To always give our customers the best user experience. When there was no smartphone on the market putting the music on the main stage, we created it," said Konrad Bergstrom, founder and president of Zound Industries, which licenses the Marshall brand.

"We know that our consumers and the open market is ready for what we have to give: a smartphone by default, developed into the world's greatest music device and we promise you, Marshall London is like nothing you've ever had in your pocket."

From a design perspective, the London fits in with Marshall's family of audio products. It has a matte black surface, similar to the skin of Marshall amps, and the scroll wheel, M-Button and both stereo jacks are all made of brass.

The phone runs Android Lollipop, which Marshall claims offers low latency audio input. It has a 4.7-inch screen, 2GB of memory and 16GB of storage, which is expandable with a microSD card. It also has a removable 2500 mAh battery, an 8MP rear camera and 2MP front camera.

The London will be available in 22 countries worldwide for £399. Anyone who pre-orders the device on the Marshall website will get a free pair of Monitor headphones. Devices will begin shipping in late August or the middle of September, depending on country.