SGA1566 – Free Tube Saturation VST/AU Plugin By Shattered Glass Audio


SGA1566 by Shattered Glass Audio.SGA1566 is a freeware vintage tube preamp emulation in VST/AU plugin format for Windows and Mac based digital audio workstations, released by Shattered Glass Audio.

The plugin emulates a vintage single channel tube preamplifier, featuring two 12AX7 tube amplification stages and a two-band Baxandall equalizer which can be placed either at the input or the output stage. The plugin also features two different CPU modes, offering improved stability and compatibility with older and less powerful machines. The low CPU mode is less CPU intensive, at the cost of a slightly less accurate simulation of the tube circuit.

See also: Free Saturation VST Plugins!

Loopmasters Xmas Flash Sale

Sound-wise, I really like this plugin. I love the type of saturation I was able to get out of it, especially on drum loops and synthesized bass sequences. It colors the sound in a very pleasant way, adding the right amount of tube style saturation on top. The built-in EQ also does its job rather well and it works great in combination with the tube circuit. SGA1566 is definitely worth a try if you need a device for coloring your audio tracks and adding a bit of depth and sparkle to digital sounds.

Performance-wise, things could be better. The default setting takes around 25% CPU on my Intel Core i3  processor (tested in a 64-bit DAW). The low CPU mode drops this value by around 10% and turning off stereo mode can reduce the CPU hit a bit more. On the other hand, increasing oversampling from 1X to 4X on the default setting increases the CPU hit to over 90%. Either way, the plugin definitely sounds good enough that I can see my self using it for offline editing and sound design in the future, however I doubt that I’ll be using it as an insert in music projects too often.

But that’s a fair trade-off. I’ll always take a great sounding effect which puts a bit more strain on the CPU and bounce the track when I’m happy with it, than a low quality plugin which just doesn’t sound that good. I actually found that it’s significantly beneficial to my workflow when I bounce a track which uses CPU intensive plugins and then simply remove those plugins from the project. It eliminates the temptation of re-tweaking various plugin parameters later on in the mixing stage.

Shattered Glass Audio has recently released another interesting freeware plugin called Ace. It is a rather spot-on emulation of the old Fender Champ guitar amplifier, perfect for getting that creamy vintage guitar tone ITB.

Audio Demo

Check out the SGA1566 audio demo:


SGA1566 is available for free download via Shattered Glass Audio (1.12 MB download size, EXE installer, 32-bit & 64-bit VST/AU plugin format for Windows).

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About The Author

Tomislav is a journalist, music producer and web designer from Belgrade, Serbia. He is also the owner and editor-in-chief here at Bedroom Producers Blog.


    • Karl, SPICE like circuit simulation of non-linear circuits is extremely computationally intensive. Read Shattered Glass Audio’s explanation above, or do a Google search.
      Educate yourself before making another scathing comment.

      • @ “James”

        Okay, I’m going to educate myself now, since you requested me to do so. lol

        Back to reality: What is “scathing” about my opinion which is strictly based on my perspective as a user. A appreciate what those guys are doing very much and still I point to the usability as the foremost aspect. If you want to be an ass-eating fan boy, go somewhere else “James”!

  1. Bug in latest version of Reaper: When stereo mode is on, the sound goes from right channel only. After switching to mono it does not produce any sound at all. The project was set to 96kHz, 24 bits. OS – Windows 8.1 x64
    I am away from PC at the moment and will give more details later. Cheers!

  2. 64-bit version doesn’t load for me at all in Reaper or Sony Vegas. It seems to be an invalid dll…

  3. @UserFX
    Because your whole analysis is based on the incorrect use of Voxengo SPAN and noisy “testing” environment.
    I don’t want others to waste time, like I did, trying to replicate non-existent issues.

    • There is no noisey environment. The plugin runs in the DAW and the only noise comes from the plugin itself. The DAW is completely quiet.

      Trying to discard my analysis because of a supposedly noisy environment that doesn’t exist and a different setting in SPAN (which isn’t as

      important in regards to the issue at hand as you claim it is) is a disgeniuous attempt to discredit my experience.

      Everything I encountered I have described in detail and documented in the videos I linked earlier. This isn’t a matter of opinion, it’s a matter

      of facts and evidence as everybody can see for themselves in those videos.

      You’re not discussing the plugin’s bugs that are shown in the videos – the worst of which is probably the lingering high frequency tones it

      emits. Instead you are ignoring them and you’re creating straw men (noisy environment, wrong usage of tools etc.) to deflect from the actual

      problems and even claim they don’t exist.

      Don’t do that. It’s a disingenuous way of arguing. If you don’t experience these bugs, that’s great. But I experience them and more importantly

      I have demonstrated their existence in the videos.

      Other people have run into different problems with the plugin that I did not encounter, such as the dll not loading.

      • Your whole analysis is based on an incorrect use of Voxengo SPAN. That in and of itself is sufficient to make your whole analysis UTTER RUBBISH!
        Stop spreading misinformation and wasting people’s time!

        • Roman you are doing something wrong or maybe you have an old(er) version.
          With no input oversampling at 4x, CPU set to HIGH, and everything set to default values the output reads about -110 to -115 dBFS. This confirms what GTR was saying.

  4. Just tried to install and my antivirus says the 64 bit installer is infected. I checked online and it seems that many other AV engines report the same. Shouldn’t be a false negative then, or is it? The 32 bit version is fine.