The debate between hardware versus plug-ins has cooled over the last couple years as plug-ins are getting better and better. However, Acustica Audio seems happy to stoke the fires with their El Rey compressor plug-in, gaining a lot of attention and buzz for rivaling its tube hardware inspiration. Developed in conjunction with producer/engineer Greg Wells [Tape Op #123], the El Rey compressor was meticulously modeled after the famous RCA BA-6A Limiting Amplifier. Greg’s goal was to create a mixing “secret weapon” that would provide analog weight and body to a single track or even the mix bus. If you’re thinking, “Blah blah blah, buzz words!” then don’t read the manual for this plug-in! It’s like reading the Instagram comments from a millennial influencer’s wedding post (note: I’m a millennial). But how does El Rey sound? Excellent!

Using El Rey is pretty straightforward. You’ve got Input gain, Threshold, five fixed Attack and Release settings (ranging from “slow” to “fast”), Make Up gain, a Dry/Wet knob, a sidechain filter (ranging from 50 to 250 Hz). They’ve also included a cool Auto Gain switch, which allows you to drive the Input of the plug-in while inversely reducing the output gain so there is no perceived volume change. This is useful when trying to dial in compression tones without being tricked into thinking louder is better.

My initial reaction when loading up El Rey on a female lead vocal track was how smooth it sounded and reacted when getting 12 to 15 dB of gain reduction. With the Attack set to medium-fast and the Release set to medium-slow, I was reminded of how the Retro Instruments 176 Limiter Amplifier [#66] (my go-to when mixing or tracking at Jackpot! Recording Studio) sounds on vocals but with a little more grit. You can slam this plug-in without really getting any ugly grabbing or pumping artifacts, and it remains musical even in extreme settings. Next, I tried El Rey on a bus consisting of about ten cello tracks. My biggest challenge when working with large cello sections, is being able to control the booming low end while letting higher melody lines cut through without being harsh. I was extremely happy with how well the El Rey held things together while still allowing the dynamics of the arrangement to move – the filter on the sidechain works great in these scenarios!

It wasn’t until I strapped El Rey on my drum bus that I really started to hear the “glue” factor that everyone keeps raving about. With a medium attack, fast release, and the filter set to about 100 Hz, I noticed an instant thickness to the drums. The same can be said when used on a bass track. The squishy reaction of the compressor gives the low end a rich tone that fills things out in a mix without getting muddy. The vibe and sound it emits are retro enough that I probably won’t find myself reaching for it on pop drums, but it has already become one of my favorite compressors to use on electric or upright bass and both male and female vocals.

El Rey uses a sampling technology “based on the Vectorial Volterra Kernel Series” which allows Acustica Audio to faithfully sample the hardware at all input stages and settings, thus recreating a perfect tridimensional response of how audio passes through a piece of gear (including phase variations and quirks of the hardware at all frequencies, all dynamically represented). They also sample harmonic distortion variations as well. Perhaps due to this technology, El Rey seems to require more system resources than I expected – I started getting CPU usage alerts after loading about five stereo instances of the plug-in. My only other critique is that the controls lag a bit on my system, making it hard to perform a smooth bypass of the plug-in to A/B your compressed verses non-compressed signals. Other than that, this is a fantastic tool that really does sound thicker than almost all other compressors in my plug-in library. It imparts tons of vibe, does an incredibly musical job of reining in dynamic instruments, and really glues a mix together. I highly recommend downloading their free trial version of El Rey to see for yourself! Special thanks go out to Aaron Hellam <> for bringing this plug-in to our attention.

Tape Op is a bi-monthly magazine devoted to the art of record making.

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