As the Covenant of the Phoenix community begins the debate over which of these two voice chat programs will be best for the long-term, I've gathered a few reviews from around the MMO universe:
From joystiq.com:
Overlay:
Mumble overlay is a native feature of both Mumble and Ventrilo; it allows you to see everyone who is in channel or just who is actively speaking. Both offer customization options allowing for moving the position, changing the font and the color, and showing only who is currently talking. Mumble allows slightly finer adjustment on positioning as well as changing the font size, but I would say that both are close here.
Low latency
As a raid leader, I'm acutely aware of voice chat latency. I even went so far as to set my Deadly Boss Mods bars to shift from small to large at 7 seconds simply because I wanted to take into account a split-second human lag plus a half to full second of Vent lag. "Meteor in five seconds" should mean "Meteor in five seconds," not "Meteor in three seconds by the time you hear this." Mumble was specifically created for low latency, and it lives up to its promise. There is just about as much lag as you'd have on a normal phone call or a mobile call with good reception.
Low latency is the main reason I will never go back to Ventrilo and is my biggest annoyance when I am forced to go back to a Vent server. The latency is so low on Mumble that it allows for normal conversation, and "Meteor in five seconds" means "Meteor in five seconds."
Auto normalization
How many times have you been in Vent when someone new pops in -- or someone with a new microphone -- and they destroy your eardrums? What happens then? Either everyone forces that person to change his advanced volume settings or they immediately open up their advanced settings and turn that person down. Twenty-four people adjusting their settings to level out one single person, does that seem right to you?
"OK, say something now," the Vent adjusters say, followed by some tweaking and another, "OK, say something again." Even if you follow the obscure and complex settings for Vent normalization, you still end up needing to turn people up and down because it's not perfect.
Mumble normalizes volume automatically. How do you turn someone up or down? You don't. The server does it for you and does it right. In four months of using Mumble, I've never had my eardrums blown out once, and anyone who's sounded quiet has been quiet because of a bad mic or mic-on-head syndrome.
That covers most of the straightforward features and really the two most important: latency and normalization. But what about some more advanced features? Without getting too complex, I'll dive into a few next.
Security
In the world of IT security, authentication > password. Vent uses password-based security; Mumble uses authentication. As a Mumble user, you create a certificate that creates a public/private key pair. This type of security means the admin doesn't have to change passwords and the users don't have to worry about their passwords residing on someone's server. It also allows the admin to assign permission levels based on your certificate, and your certificate is portable across servers.
From an administration standpoint, user permission levels can be set at the root level or individually per channel. For example, anyone with our Mumble server address can enter our server, but to enter our raiding channel, you must be both registered to the server and added to the custom permission group I created for that channel. This way, if someone were to pop on our server while we're raiding, they would not be able to enter our raiding channel. In short, the administration options are far more granular and much easier to use than Vent's. (For my fellow IT geeks: Mumble uses Access Control List permissions.)
Positional audio
If you play with surround sound or have a headset that supports surround sound, you can enable positional audio in Mumble. This can be enabled and adjusted on a per-player basis.
Cons: Árthás and Mumble
There are many other features of Mumble that I haven't covered here, but I think I've professed my love for it enough so far that I should cover the only downside to Mumble. Because Ventrilo is so widespread in the world (of Warcraft) it's the defacto choice for PUG raids. If you run a lot of PUGs or have a vibrant PUG community on your realm, getting them all up and running in Mumble can be quite a challenge. Imagine trying to explain to Árthás, the unholy DK who gemmed for agility, what Mumble is, where to get it and how not only to install it but also create a certificate. Oh, and to set up push-to-talk because his mic is open and we can hear his heavy breathing.
Granted, it's not difficult to get Mumble up and running -- but different users have different levels of technical savvy and throwing something new in the works will stop those less savvy dead in their tracks. Everyone uses Ventrilo, so it's quick and easy for PuG raids to get going. But hey, I hear after the raid, "everyone" is heading down the bridge to jump off, so call me afterwards and let me know how it goes.
source: joystiq.com
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