Home Assistant Connect AUX-2 Is Here: The Smart Home Multi-Tool for Audio, Serial, Z-Wave, and Bluetooth, Now at Apollo Automation
Home Assistant Connect AUX-2 is here, and you can buy it from Apollo Automation today. Made by Nabu Casa, the company behind all official Home Assistant hardware, AUX-2 is a small box with one goal, making the devices you already own smart.
That old hi-fi in the living room, the TV with the app you don't trust, the solar inverter in the garage, the Z-Wave stick stuck behind your server. AUX-2 brings all of them into Home Assistant, and it runs on a single Power over Ethernet cable.
Buy Home Assistant Connect AUX-2 from Apollo Automation
- What Connect AUX-2 does
- Synced audio for your hi-fi
- RS-232 serial control
- Z-Wave and Bluetooth
- Specs
- AUX-2 and CAST PRO-1
- FAQ
What Connect AUX-2 does
AUX-2 does four jobs at the same time.
- Whole-home synced audio. CD-quality analog or optical audio for your hi-fi or AV receiver, in sync with your smart speakers through Music Assistant.
- Advanced serial control. Two RS-232 ports to control TVs, receivers, projectors, solar systems, UPSs, and more, even in standby. RS-485 works with a USB adapter, sold separately.
- Z-Wave anywhere. Plug in a Connect ZWA-2 and move your Z-Wave network to the best spot in your home, powered by PoE.
- Bluetooth hub. A dedicated antenna brings Bluetooth smart home devices into Home Assistant over a wired connection. Bluetooth audio is not supported.
Setup is plug and play. Home Assistant finds AUX-2 on your network, and a setup wizard walks you through each feature.
Bring your old hi-fi back
Plenty of great-sounding amplifiers and receivers have an optical input and a serial port on the back. Connect AUX-2 to both and you get lossless audio plus control of power, volume, and source.
Pair it with Music Assistant to play Spotify, TIDAL, or your own FLAC files on that hi-fi, in sync with the HomePods, Sonos, and other speakers around your home. Sync runs on Sendspin, the open audio protocol from the Open Home Foundation, so AUX-2 also plays in sync with our CAST-1 and CAST PRO-1.
As Home Assistant founder Paulus Schoutsen put it, "The most sustainable device is the one you already own."
RS-232 serial control, explained
Serial (RS-232) is a two-way wired connection that manufacturers have put on the back of AV receivers, TVs, projectors, and energy gear for decades. It doesn't need the cloud, so it keeps working after a company shuts down its app, and your data stays home.
With AUX-2 you can:
- Turn your receiver on and set the volume from an automation
- Control your TV locally, then block it from phoning home
- Read energy data from a solar inverter, battery, or heating system
- Connect Modbus and RS-485 devices with an inexpensive USB adapter
Z-Wave and Bluetooth where you need them
Z-Wave works best from the middle of your home, not from a server closet. Plug a Connect ZWA-2 into AUX-2's USB port, run one Ethernet cable, and put your Z-Wave network wherever it reaches the most devices.
The same goes for Bluetooth. AUX-2's dedicated antenna works as a Bluetooth proxy for sensors, locks, and other Bluetooth smart home devices, with up to three active connections.
Built to be tinkered with
AUX-2 runs ESPHome with an unlocked bootloader, so you can load custom firmware. It has a Grove port for adding sensors, it's easy to take apart, and Nabu Casa plans to release the PCB and 3D-print files. It works out of the box, and it's yours to change.
Buy Home Assistant Connect AUX-2 from Apollo Automation
Home Assistant Connect AUX-2 specs
- Processor: ESP32-S3R8, 8 MB PSRAM, 8 MB flash
- Audio DAC: TI PCM5122, 112 dB SNR
- Audio out: 3.5 mm analog or optical (S/PDIF), one at a time, output only
- Audio format: 16-bit, 48 kHz stereo, lossless digital. FLAC, MP3, and WAV
- Whole-home audio: synced through Music Assistant (Sendspin)
- Serial: 2x 3.5 mm RS-232 (±5 V) with TX/RX switch
- USB-A: Connect ZWA-2 or a USB to RS-485 adapter (sold separately)
- Grove port for sensors
- Wi-Fi: 2.4 GHz, 802.11b/g/n
- Bluetooth: Bluetooth 5 LE, proxy with up to 3 active connections
- Ethernet: W5500 controller, PoE (802.3af or better)
- Power: PoE or USB-C (5 V, 2 A). Typical draw under 1 W
- Software: built for Home Assistant, built on ESPHome, unlocked bootloader
- Size: 106 x 63 x 25 mm, 104 g
- Enclosure: polycarbonate, white and semi-transparent
- In the box: Connect AUX-2, warranty and safety leaflet, Home Assistant sticker. USB-C and Ethernet cables not included.
- Requires: a Home Assistant system
Connect AUX-2 and CAST PRO-1
We get asked how AUX-2 fits next to our own audio devices. Both play synced audio through Music Assistant and Sendspin, so they work together in the same home.
- Pick Connect AUX-2 if you want serial control of a receiver or TV, a better spot for Z-Wave, or PoE power.
- Pick CAST PRO-1 if you want to send a record player, CD player, or TV into Music Assistant through its Line In, or drive an LED strip. Read more in our CAST PRO-1 post.
- Pick CAST-1 if you only need to make a powered speaker smart.
Why buy from Apollo Automation
We're an official Home Assistant distributor and a commercial partner of the Open Home Foundation, alongside Nabu Casa. When you buy AUX-2 from us, you're supporting a small team in Kentucky, and Nabu Casa's share of every sale funds the development of Home Assistant. We know this hardware, and we're happy to help you get it set up.
Want the full announcement? Watch the AUX-2 launch livestream or read the Connect AUX-2 page on home-assistant.io.
Connect AUX-2 FAQ
What is Home Assistant Connect AUX-2?
Home Assistant Connect AUX-2 is a smart home multi-tool made by Nabu Casa. It streams audio to your hi-fi or AV receiver, controls RS-232 serial devices like TVs and solar inverters, moves a Connect ZWA-2 Z-Wave adapter to a better spot on your network, and acts as a Bluetooth proxy, all at the same time.
Where can I buy Home Assistant Connect AUX-2?
You can buy Home Assistant Connect AUX-2 from Apollo Automation, an official Home Assistant distributor in Versailles, Kentucky.
How much does Connect AUX-2 cost?
The suggested retail price is $69 USD or €59 EUR. Prices can vary by region and retailer.
Do I need Home Assistant to use Connect AUX-2?
Yes. A Home Assistant system is required to connect and control devices with Connect AUX-2. Home Assistant finds it on your network, and a setup wizard walks you through each feature.
Does Connect AUX-2 support Power over Ethernet?
Yes. It runs on Power over Ethernet (802.3af or better) for a single-cable install, or on USB-C power (5 V, 2 A) with Ethernet or 2.4 GHz Wi-Fi. USB-C and Ethernet cables are not included.
What audio outputs does Connect AUX-2 have?
It has one 3.5 mm jack that does analog or optical (S/PDIF) output, one at a time. Audio is 16-bit, 48 kHz stereo from a TI PCM5122 DAC, and it plays in sync with other speakers through Music Assistant and Sendspin. It is output only and does not support Bluetooth audio.
What is RS-232 serial control?
RS-232 is a two-way wired connection that many AV receivers, TVs, projectors, and energy systems have had for decades. It works locally with no cloud, so Connect AUX-2 can turn up the volume, change inputs, read energy data, or wake a device from standby. It has two RS-232 ports, and RS-485 or Modbus devices work with a USB adapter sold separately.
Does Connect AUX-2 work with Z-Wave?
Yes, with the Home Assistant Connect ZWA-2, sold separately. Plug it into the AUX-2's USB-A port and place both in the best spot in your home for Z-Wave coverage, powered over PoE.
Is Connect AUX-2 a Bluetooth proxy?
Yes. Its dedicated antenna brings Bluetooth LE smart home devices into Home Assistant over a stable wired connection, with up to 3 active connections. It does not support Bluetooth audio.
Can I customize Connect AUX-2?
Yes. It runs ESPHome with an unlocked bootloader that accepts custom firmware, and it has a Grove port for adding sensors. Nabu Casa plans to release its PCB and 3D-print files.
What is the difference between Connect AUX-2 and CAST PRO-1?
Both stream synced audio with Music Assistant and Sendspin. Connect AUX-2 adds RS-232 serial control, Z-Wave through Connect ZWA-2, PoE power, and a dedicated Bluetooth antenna. CAST PRO-1 adds a 3.5 mm Line In, so a record player, CD player, or TV can become a source in Music Assistant, plus LED strip terminals. They work together.
What is in the box?
Connect AUX-2, a warranty and safety information leaflet, and a Home Assistant sticker. USB-C and Ethernet cables are not included.
Thank you, Nabu Casa
Congratulations to the Nabu Casa team on the launch. AUX-2 is a great example of what Home Assistant does best: giving people control of the devices they already own. Grab yours from us, and show us what you connect on the forum.
Buy Home Assistant Connect AUX-2 from Apollo Automation
Apollo Automation designs, engineers, and manufactures privacy-first, locally-controlled smart home sensors in Versailles, Kentucky. Every product features 100% local control with no cloud dependencies or subscriptions required. Apollo is a Works With Home Assistant partner, Made For ESPHome certified, Works With Homey certified, a BBB Accredited Business, and the second official commercial partner of the Open Home Foundation. Learn more at apolloautomation.com.
#HomeAssistant #ConnectAUX2 #NabuCasa #MusicAssistant #Sendspin #ESPHome #OpenHomeFoundation #RS232 #ZWave #PoE #HiFi #SmartHome #ApolloAutomation
