Amp sims Audio Assault Reviews

Audio Assault Sigma

Audio Assault has upped their game and released some really good, really affordable software lately. Is the Sigma one of these?

Rating: 8/10

Rating: 8 out of 10.


Audio Assault has been releasing insanely-affordable software for musicians for a pretty long time. It took the company a while to find their flow but they have really started to elevate their game to a much higher level. They have started doing amp sims in a bit of a different way than the past and the new tech has brought much better tones.

Sigma seems to be based on the Powered By Omega Granophyre. The Granophyre (formerly know as the Iridium) is based on the lead channel of the company’s more elaborate Obsidian amp.

The plugin includes an IR selection from Seacow Cabs and a fixed-position boost. These amps are becoming phenomenally popular in a hurry as many big name players are switching to the new brand. Are they worth the hype? In my opinion, yes.


SIGMA’s GUI is simple and effective. They have created a single panel layout that is easy to use, so easy in fact that I would highly recommend the plugin to beginners. Don’t get me wrong, experienced users will find plenty to love in this plugin but for beginners to have such an easy way to sit down and chug with tones this good is great for the market.

It’s astonishing how good the tone is without having to really do a single thing to the controls. Many developers strive for that perfect “first impression tone and Audio Assault have delivered that here. There’s a very simple control set up with gain, focus, EQ, presence and more that can be used to get where you need to go quickly.

Let’s be honest here, this amp sim is not going to be the one you reach for when you feel like creating lush cleans or country twang. It’s basically set up to kill at all times so users will find it much easier to use SIGMA for it’s skin peeling high gain capabilities. Sure, it’s easy enough to get reasonable mid-gain tones but not to a level that I would say is a strength for the plugin.

High gain lovers however will find tones to chug, shred, trem pick and CHONK their way right into any aggressive style. Djent, thrash, death metal, tech-death, black metal, seriously.. anything in the high gain realm is more than achievable with SIGMA without a fuss. It plays well on it’s own or in many different styles of mixes. It doesn’t get buried easily in a mix and it doesn’t require a lot of processing to sound great.

SIGMA brings another collaboration between Audio Assault and Seacow Cabs. In the past, AA plugins tended to struggle in the cabinet section but that’s a thing of the past. As a result, SIGMA has a very reliable selection of IRs/cabs that cover a lot of ground. Having a few very different cabs really helps the limited amp hit a lot more applications with effectiveness. With the IR/cab section being so important to the quality of a plugin, this was a great move for the companies to link up. Users can also bypass the internal IR section for their own if they choose. When doing so, SIGMA has always played well with other IRs for me.

There’s no boost section specifically but users can simply click the boost box in the GUI to kick in a fixed-position boost. Imagine setting up your tube screamer where you like it and then breaking the knobs off. Not sure what the settings are but the switch works nicely to create some extra bite without being too aggressive. For those that want more bite, you can either stack the boost of your choice in front of SIGMA in your chain or simply leave the internal boost off to have your own lead the charge. I found the amp boosted nicely with everything I threw at it.


The tones available inside SIGMA don’t make sense when you see the price. Don’t let the price fool you though, this is not a low quality product. Audio Assault could easily be charging more for this but instead, it’s affordable for all which is a great thing for amp sim users worldwide that either don’t have much of a budget or are just looking for another tool for the box.

The difference in quality from Audio Assault’s earlier high gain products is quite large, SIGMA is easily the best sounding amp sim the company has put out to date. It’s a very large step forward for the company that will bring their name and plugins to many new users to come. It’s great to see such a high level improvement and I can’t wait to see what players worldwide will do with SIGMA and their future products.

On the downside, the plugin’s controls don’t really have a whole lot of flexibility. They have somewhat of a “player” feel rather than authentic. The controls are most useful from about 3.5 to 7 but beyond that, they start to get fizzy and less useful. I find big control moves outside of those parameters just tend to cause things that I just wanted to EQ out. Those looking for an authentic Powered-By-OMEGA experience may not find it here but the plugin’s pros drastically outweigh it’s few cons.

See more: HASR demo of the Sigma by Johan Lund

%d bloggers like this: