for broadcast use in Radio and Television, AudioTX STL-IP product range is an
easy to use, cost-effective solution to audio delivery over IP networks and the Internet.
It is an established and proven product line with now over 10 years in the field and, new for 2014, a major upgrade in the STL-IP Plus with SureFlow technology. The STL-IP line is absolutely unique in offering the same
quality, robustness and low delay as conventional audio circuits,
but with the flexibility and low cost associated with using IP connectivity.
The highest audio quality
STL-IP products sound better. There, we've said it. STL-IP uses professional grade encoders designed for broadcast and professional audio use. Each coding algorithm is designed for us and tweaked to squeeze every last bit of quality out of your available bitrate. Each is exclusive to STL-IP. We offer a full range of audio options - from linear (uncompressed/PCM) through mathematically lossless coding types, near-lossless variants and perceptual codecs (like MPEG coding for example) and ADPCM variants including APTx. The difference in audio quality between STL-IP and other units is not small or subtle. It's obvious. Why not have a listen to our audio samples via the Hear It link at the top of the page.
The most reliable performance over the best and worst networks - and the Internet
AudioTX STL-IP was first released in 2004 and we've been supplying the world's leading broadcasters with solutions for audio over IP since 2000. That's from the time that others were still suggesting that IP and the Internet would never be suitable for broadcast use. The experience and know-how we have built-up over that period is included in every one of our products. We know, and our customers see for themselves, that if you put STL-IP head to head with other manufacturers' units on real-world networks, STL-IP wins hands-down, still delivering reliable audio on networks that other units find problematic. Still sounding good whilst the others are glitching and cutting out. Today, in 2014, you can still buy the original STL-IP from us - we call it the STL-IP Classic today - and it's still a cutting-edge product, continuously updated and refined. Or choose the STL-IP Plus which includes our SureFlow Technology... that's a system that can combine up to 5 truly independent, redundant streams, sent over one or more networks/connections and each stream can be independently encoded using different coding algorithms and bitrates to suit. At the receiving end, STL-IP Plus seamlessly checks, chooses, filters and fixes, picking from the best quality audio available down to each and every sample for perfect audio. And you can choose to add one of two grades of Forward Error Correction to any or all the individual streams, add a safety/jitter buffer of up to 60 seconds (yes you read that correctly) and then still choose from a whole host of backup audio options - from locally stored (and remotely updateable) audio files to alternate sending sources, web streams, or even locally available audio inputs. All in all it's as close to 100% reliability as it gets.
The lowest delay
When we talk of low delay, we mean it in simple and honest terms. AudioTX
STL-IP delivers many audio types with just a 5ms delay. That's a real 5ms from the input of one device to the output of another and on a real-world network. That includes linear PCM audio, ADPCM, near-lossless J.41 and DAT 12, FLAC and others. We deliver Enhanced APTx audio with just a 9ms delay - again, that's an end to end delay. And on all other coding types, for example MPEG and AAC types, STL-IP's delay matches the theoretical minimum as specified by the standards themselves. Of course you can add jitter/safety buffers where needed... but again, our approach is honest here too... STL-IP products are designed to be used with a zero jitter buffer on most reasonable networks and our delay figures quoted are those that we expect you to actually achieve. Ask us if you have particular needs or want to understand what's possible!
The short version
STL-IP provides the perfect solution for audio over IP - whether
you need an IP based STL (Studio Transmitter Link), or to distribute
shared programming over networks, connect studios, replace conventional
permanent audio circuits or even for ad-hoc connectivity like Outside
Broadcasts/Remotes. It works over existing private networks like
LANs and WANs, Telco networks, Private leased lines like T1/E1,
MPLS, Wireless networks (both professional and WiFi), Mobile networks like 3G/4G and others, Satellite and even
balanced audio connections and AES/EBU digital inputs and outputs
are provided on XLR connectors and, where required, the system can
accept an external wordclock signal, or sync to an external digital
signal. AudioTX STL-IP also allows for the transmission of ancillary
serial data and/or contact closures (GPIO) alongside and in perfect
sync with your audio.
A single unit can simultaneously transmit your audio to up to 66 different
'connections' and receive audio from multiple locations as backup sources independently of the sent audio. Each 'connection'
can be independently set to use TCP/IP, UDP or UDP Multicast networking
- sending audio to an unlimited number of receiving units. Mono
or Stereo audio can be sent in Linear (uncompressed) mode at up
to 24bit, 96kHz, or using MPEG Layer 2 and MPEG Layer 3 coding,
J.41, DAT12, ADPCM or extra Low-Bitrate speech modes. Plus
AAC Low-Delay and HE-AAC v2 (AACPlus) with the optional AAC Codec
Pack which allows you to send Stereo audio from just 14kbps! and there's also professional grade OPUS and lossless FLAC available too. You
can also choose Enhanced APTx coding with the optional APTx Codec
Two grades of switchable
FEC (forward error correction) and adjustable network jitter buffers
allow the system to function perfectly even on busy and difficult
STL-IP is configured via a standard web-browser on the network -
settings can of course be password protected. Once configured, your
connections will be maintained... in the case of network failure
or power loss, the system will reconnect when network connectivity
or power returns. A simple, text-based Telnet-like remote interface allows for easy integration with other existing management/scheduling systems, plus there are alerts via SNMP and/or email, included quick monitoring software and local hardware status outputs on the device.
STL-IP-8 and STL-IP-16 units have multiple inputs and outputs (16
inputs and outputs in a single unit for the STL-IP-16 and 8 inputs
and outputs on the STL-IP-8) and these are perfect for larger scale
installations and projects, or just where you need to send and receive
multiple channels of audio.
The STL-IP Connect software is designed for news/sports reports, remotes/outside broadcasts and the like and provides a consistently reliable solution, far superior to the more generic and mobile phone based applications currently offered, in terms of audio quality, reliability and low delay.