All item sounds, emotes and trails are part of what is known as the "optional content pack". This content pack is optional and does not download automatically when you connect to any of of our community game servers. This is done to eliminate download times for players who only want to play on the servers without ever using these items.
The content pack can be obtained by connecting to the content distributor at the IP address: download.titan.tf:11111
Don't worry, the installation process is automatic and the game will notify you as soon as it finishes installing. The simplest way to connect to it via the IP address is to enter the following line into the address bar of your browser.
Alternatively, you can enable your Team Fortress 2 developer console and connect through it by following the screenshots below.
Updating is the same as the installation process. You can update your content pack by connecting to the content distributor at the IP address: download.titan.tf:11111
Similarly, you can follow the connection guide in the installation section above if you do not know how to connect to a server using the server's IP address.
Players who do not download the optional content pack will not see the emotes you use, trails you are wearing, and the sounds you play. Others who download them will be able to see and hear them.
You can adjust the volume of sounds played if you have the optional content pack installed. Head over to settings, and follow the screenshot below.