High quality audio Wi-Fi streaming using the the popular WiSmart EC32L13 module and embedded with Econais audio streaming application software.

The Econais WisAudio Wi-Fi audio reference design is an innovative solution using on-the-fly decoding for streaming music and sound. Needing less bandwidth than traditional WAV streaming approaches, while keeping the ability to play high quality WAV audio, WisAudio offers a very high quality sound with MP3, FLAC, WAV and a variety of other audio stream formats. WisAudio is an ultra low power consumption solution using encoded audio due to lower data traffic and on-the-fly decoding by the audio codec.

The design is very compact and is easily fits within an earpiece or audio headset. Supports DLNA and every modern popular OS(iOS,Android, Windows, etc.) and any Smartphone (iPhone, Android, Windows, etc….), use it turn-key with any of the free DLNA applications in Google Play or App store. To learn more, watch a Demo in our “Demo Videos” page or on youtube. Download reference design brochure from here.

The industry’s most advanced audio streaming characteristics and still a low cost solution for even the highest audio quality needs. Includes license for MP3 and AAC.

The WisAudio reference design provides have high sound quality for WiFi headsets or speakers which could be used to:

  • Stream audio data from PC and other devices (i.e. smartphones and tablets) to one or multiple headsets or speakers
  • Provide superior audio quality with non-encoded and encoded audio data over the air (i.e. WAV, FLAC, or MP3) while using less bandwidth, less power consumption, and providing long range.

The WisAudio solution uses our proven Wi-Fi module with an embedded ARM Cortex-M3 MCU running the TCP/IP stack, the Wi-Fi authentication and security protocols including WPS, SoftAP, Wi-Fi client and Ad-Hoc modes and combine it with VLSIs VS1053 Audio CODEC, one of the most advanced Audio CODECs in the market today.

The result is very low power and hi-quality audio stream natively supporting WAV/OGG/MP3/AAC/WMA/FLAC/MIDI formats with on-the-fly audio decoding.

The abstract block diagram of the ref. design is as follows.

The solution supports the following audio formats:

  • Ogg Vorbis
  • MP3: MPEG 1 & 2 audio layer III (CBR + VBR + ABR)
  • MP1/MP2: layers I & II optional
  • MPEG4/ 2 AAC-LC(+PNS), HE-AAC v2 (Level 3) (SBR + PS)
  • WMA 4.0/4.1/7/8/9 all profiles (5-384 kbps)
  • General MIDI 1 / SP-MIDI format 0 files
  • FLAC
  • WAV (PCM + IMA ADPCM)

WisAudio offers many benefits comparing to unencoded audio streams and/or other wireless technologies:

WAV vs encoded audio (why encoded audio)

WAV Encoded audio
(WAV/OGG/MP3/AAC/WMA/FLAC/MIDI)
  • High audio quality
  • 2 channel stereo sound demands network bandwidth up to 3Mbps
  • A simple additional DAC is enough to reproduce the sound
  • Significantly higher power consumption due to larger amount of data to be transferred
  • More sensitive to WiFi rate drop by the distance
  • In wireless systems, it is tricky to go beyond 48Ksamples/s using 16-bit stereo DAC with WAV due to the high bandwidth requirements and precise timing for the DAC
  • High audio quality stream, encoded by lossless or lossy standards.
  • 2 channel stereo 320kbps MP3 audio needs up to 400Kbps network bandwidth
  • The transmitted sound is decoded on the fly by the headphone without the need of expensive big buffering nor high processing power CPU
  • Saves enormous power consumption as the transmitted data are 10 or more times less than in WAV
  • Easier to implement multiple channel audio and go beyond the 48K samples/s, 16-bit stereo barrier of WAV

Bluetooth vs WiFi wireless audio

Bluetooth Wi-Fi
  • Range: 5-10m
  • Number of concurrent streams: up to 2 connected devices, barely 1 WAV stream due to bandwidth limit
  • Sound quality: Fair
  • Immunity to interference: Average. Gets worst as the channels get more congested.
  • Interconnectivity/compatibility: restricted.
  • Compatibility: Limited. Only devices with the same generation of BT can utilize all the functions. Non-BT devices cannot be used at all.
  • Range: 25-40m in-house, up to 400m open space in line of sight
  • Number of concurrent streams: 100s with MP3, more 10 WAV streams
  • Sound quality: excellent
  • Immunity to interference: Very high
  • Interconnectivity/compatibility: Wide. Virtually unlimited due to support of advanced media standards like DLNA.
  • Compatibility: speakers/headset can cover the whole house, and every device that has network connectivity can use it regardless if it is wireless or not.
  • 802.11 is a fast growing standard that gets more capabilities every year.

 Audio Characteristics

Parameter

Symbol

Min

Typ

Max

Unit

DAC Resolution

18

bits

Total Harmonic Distortion

THD

0.07

%

Third Harmonic Distortion

0.02

%

Dynamic Range (DAC unmuted, A-weighted)

IDR

100

dB

S/N Ratio (full scale signal)

SNR

94

dB

Interchannel Isolation (Cross Talk), 600 + GBUF

80

dB

Interchannel Isolation (Cross Talk), 30 + GBUF

53

dB

Interchannel Gain Mismatch

-0.5

0.5

dB

Frequency Response

-0.1

0.1

dB

Full Scale Output Voltage (Peak-to-peak)

1.64

1.85

2.06

Vpp

Deviation from Linear Phase

5

o

Analog Output Load Resistance

AOLR

16

30

Ω

Analog Output Load Capacitance

100

pF

Microphone input amplifier gain

MICG

26

dB

Microphone input amplitude

48

140

mVpp AC

Microphone Total Harmonic Distortion

MTHD

0.03

0.07

%

Microphone S/N Ratio

MSNR

60

70

dB

Microphone input impedances, per pin

45

Line input amplitude

2500

2800

mVpp AC

Line input Total Harmonic Distortion

LTHD

0.005

0.014

%

Line input S/N Ratio

LSNR

85

90

dB

Line input impedance

80

k

 

WisAudio Rev.4

Audio Ref. Design Eval Board/SDK

 

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