Aqua Cobalt – Designed to Work
[December 2025] In recent years, we have seen some growth in the transmitter manufacturing sector. In addition to the longstanding brands, some newer companies have come to the fore, seeking attention via lower costs or increased features. Sometimes, you can get both. Interested? Ted Nahil would like you to know about the transmitters from Aqua Broadcast.
Selecting a new transmitter for your LPFM, booster or Class A radio station might be a breeze once you look closely at the Cobalt line of transmitters from Aqua Broadcast, LTD.
Aqua Broadcast was established in London, UK, where its products are made. The Cobalt line of transmitters was introduced in 2021. As you look at it, Aqua is built by engineers, for engineers!
The Cobalt line of FM transmitters all share the same feature set, regardless of power level. At the heart of every transmitter is a Raspberry Pi CM3B+ embedded module that acts as the system controller using a Linux operating system.
The Cobalt transmitter GUI is one of the cleanest out there. The GUI has the exact same look and feel in the 10-Watt transmitter as it does in the 5,000-Watt transmitter. Its intuitive design makes transmitter control and monitoring easy, regardless of power level.
WHAT IS IN THE CASE
Although some components are sourced from China (as is the case with almost every other transmitter manufacturer), the key components for the Cobalt transmitters are sourced from UK or US suppliers.
The majority of the metal work is done in the UK, with some sourced from specialized suppliers who can provide high-quality services like anodizing. The transmitters are assembled, tested, and packaged in the UK.
One major concern with any transmitter manufacturer is customer support. Aqua Broadcast has been establishing first-level support in the United States. More about that support in a moment.
EVERYTHING YOU WANT TO KNOW
Anytime you come to a transmitter – for maintenance or troubleshooting – you want to know as much as you can as quickly as possible, without having to wander around searching through a bunch of menus.
The main dashboard tab has a summary of all the transmitter parameters, including:
- transmitter information like model and serial number;
- pertinent RF information like frequency, on/off status, forward and reflected power, PA temp, PA Voltage and current, and fan(s) status; modulation; MPX power and composition; and RDS status;
- audio processing, stereo mode, exciter mode, sync (10 MHz and 1PPS) status, and network information.
To ensure easy control and maintenance, in addition to a full status display, all the transmitter parameters, settings and operating conditions are written to on-board memory. There are no SD cards to cause problems down the road.
From there, each critical parameter is accessible by its own tab, as well as the built-in tuner, audio player, automation routines, and audio stream status. By defining an automated routine, you can trigger an alarm or alert in case even a backup source goes away.
SOME UNIQUE FEATURES
There are also a few features that are unique.
Assuming a return path is available to the studio or control point, the audio monitoring function of the Cobalt transmitters allows you to listen to not only the audio that is on the air, but any audio source that is connected to the transmitter. This means that you can listen to backup audio to make sure it is good and more importantly, to make sure that it is available for use – a powerful and very useful function.
One of my favorite features is little feature that solves a problem that we have all been through at one time or another. The local/remote button on the front panel can be programmed to revert to the remote mode after a given period of time. This means that you never have to worry about leaving the transmitter site with the transmitter in the local mode and not realizing that fact until you have made your way back to the studio, for example. As I said, sometimes it is the little things that can make all the difference in a successful day!
SECURE REMOTE OPERATION
Especially today, with the constant danger from hackers, network security is a high priority.
Cobalt transmitters have two LAN ports, so the user can completely isolate the transmitter control and monitoring functions.
Furthermore, the CM3B+ and the power of its customized Linux operating system means security includes HTTPS, SNMPv3, encrypted emails and other network security measures that result in safe transmitter control, monitoring and alarm reporting.
CUSTOMER SUPPORT
Let us get back to that big concern – customer support.
Aqua Broadcast support in the United States includes an easy-to-use online submission form that notifies Aqua personnel of a customer issue. Using a remote log-in to either the transmitter or to a computer connected to it has solved almost all the U.S. support issues over the last two years. In fact, only one unit was unable to be fixed in the field this way.
For example, we recently needed to add a µMPX key to a transmitter in Logan, UT. The process involved remote access to the transmitter, the installation of the key, and a transmitter reboot. All of this was accomplished quickly without incident.
Jordan Riley, transmitter engineer for KBLQ and Cach Valley Media says of the entire setup process: “The setup was quick and straightforward. We’re using µMPX from our Omnia processors, so the cabling is minimal, it’s literally just power, network and RF. When we needed support for the key installation, Aqua was quick to the task and got us taken care of.”
A VERY RELIABLE TRANSMITTER
Currently, there are over 500 Cobalt transmitters on the air in the U.S. with an exceptional track record of virtually no failures.
Delivery time is reasonable, usually less than two weeks, and Aqua has a US dealer, SCMS, which stocks some models, and other dealers will be stocking transmitters soon.
Coupled with the powerful unique design, availability, feature set and support, an Aqua transmitter should be on your shopping list when it is time to replace an old transmitter or add a new one.
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Standard features for all Cobalt transmitters include:
- Direct to channel modulation (DDS);
- discrete analog left and right audio inputs;
- a digital MPX input (AES192);
- two LAN ports;
- an RGB front panel screen with front panel joystick control, and front panel buttons for quick functions including RF on/off, local/remote, and a user-defined button;
- support for SNMP V1/V2C/V3;
- control via the GUI, SNMP, or any of the eight GPIO inputs/outputs on the rear of the transmitter;
- a static or dynamic RDS generator;
- an internal 4-band audio processor with 25 presets (not adjustable), bass enhancement, pilot protection and a wideband AGC; an advanced automation package that allows settings changes based on conditions, SNMP messages, a GPI trigger, or through a scheduler routine;
- support for a Shoutcast or Icecast input as a main source or as a backup;
- audio failover to second or third audio inputs or to an audio player that can use internal memory or a USB stick;
- silence detection;
- audio monitoring of input sources;
- a redundant power supply in all models from the C-300 up to the C-5000;
- SFN-ready with both 10 MHz and 1 PPS inputs on the rear.
- a 3-year warranty.
Options for the Cobalt transmitter line include:
- a µMPX input that supports any industry-standard µMPX stream;
- µMPX for SFN;
- an FM tuner;
- an internal 6-band processor upgrade;
- in conjunction with 2wcom, a MoIN codec.
The last two options utilize a second Raspberry Pi processor that is completely independent of the main processor. Yes, the Cobalt transmitters can use multiple processors.
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Ted Nahil has a long experience in broadcast engineering and sales. He is currently the US Sales Representative for Aqua Broadcast. You can contact Ted at ted@Aquabroadcast.co.uk
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