For a limited time, Mercuriall Audio Software is offering the U530 high-gain guitar amp sim (previously $60) for free.
Update: This offer has expired.
The U530 is now exclusively available via the free Mercuriall Ampbox guitar rig suite, available on macOS and Windows for VST, AU, AAX, and standalone.

Mercuriall is holding the giveaway to commemorate the 10th anniversary of the U530’s release, but it has not specified when the deal will expire.
To get the free amp, click the ‘Download Ampbox’ button on the product page. You’ll be prompted to enter an email address, and then you can download the macOS and Windows versions directly from the page.
The “Get for Free” button on the U530 product page also prompts you to create an account.
However, once you do that, the site just informs you that the U530 is now only available through Mercuriall Ampbox. So, you may as well skip that step and go straight to downloading Ampbox.

Ampbox is a big boy, with 553 MB and 377 MB of downloads for macOS and Windows, respectively.
The preamp of the U530 is modeled on Engl’s E530 Modern Rock tube preamp.
The plugin’s design is quite faithful, as the entire control scheme of the E530 is replicated on the U530. Mercuriall has expanded the control scheme and also included a power amp stage.
The U530 is a two-channel amp, which is capable of clean, breakup, and high gain distortion tones. There are four different preamp tubes to pick from.
If you’d like to hear the amp, Mercuriall created a SoundCloud playlist with nine tracks featuring the U530.
I think it’s safe to say that the amp is mainly targeted at a hard rock, metal, and -core audience, as every demo is based around the aforementioned styles.
The samples show off an aggressive, high-gain sound that’s right at home for modern styles of heavy music. There’s also a demo showing off the amp on bass guitar, and I have to say it sounds pretty good on that too.
If you’re wondering why Ampbox comes in at more than 300 MB, well there is quite a bit going on under the hood.
There are several free modules, including pedals such as a flanger, chorus, delay, reverb, pitch shift, compression, three overdrives, and three distortions.
Most of the pedals are based around classic stomps, for example, one of the overdrives is inspired by the Ibanez TS-808 Tube Screamer.
Additional features include nine-band graphic EQ, eight-band parametric EQ and a noise gate.
Check out the deal: U530 (FREE for a limited time – email required)
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