Login / Register 0 items | $0.00 New @ KVR
 SQ8L / SQ8X by Siegfried Kullmann is a Virtual Instrument Audio Plugin. It functions as a VST Plugin.
Product SQ8L / SQ8X
Developer Siegfried Kullmann
Price (MSRP)
Free / TBA
Type / Tags
Plug-in, App & Soundware Format(s)
Operating System Availability
Download Released
Downloads Released
Miscellaneous Information
Copy ProtectionNone

SQ8L is a software model of Ensoniq's classic 1980s synth SQ80. The SQ80 features 3 digital wavetable oscillators for each of its 8 voices which are fed through analog 4-pole lowpass filters (-24dB gain) with resonance. Sound parameters can be modulated by 4 envelopes, 3 LFOs and several MIDI sources. The SQ80 also has a predecessor, the ESQ1, which can do most of the same stuff.

Although the technology may seem obsolete, these synths can produce a wide variety of interesting and extremely usable sounds. Thanks to the lo-fi oscillators and the analog components it can sound very digital and dirty, but also very analog and warm. Which is a good thing because modern synths often tend to sound rather clean.

The SQ8L ("L" stands for "Light") is the free demo version of the forthcoming SQ8X ("X" for "eXtended"). Besides any bugs that will be fixed in the full version and planned features that won't find their way into the light version, there are only a few limitations:

  • Polyphony limited to 8 voices.
  • Program change messages ignored.
  • Common MIDI controllers (Master Volume, Pan,...) by default have no effect and must be programmed as modulators.
  • When used with a sequencer, the only sound the host can save within the song file is the one in the edit buffer. The full version will store the entire library (which makes sense when program change messages are used).
  • LFO humanization not implemented.
  • No Split/Layer to combine several sounds.
  • No internal sequencer (and there will never be one).

The full version SQ8X will have the following additional features:

  • Combinations of up to 4 single sounds.
  • Adjustable polyphony (far more than 8 voices).
  • New Filter algorithms with different modes (lowpass, bandpass, highpass).
  • 2nd Filter and different routing modes for the filters: serial, parallel, split.
  • Improved GUI.


Discussion: Active
2 December 2013 at 12:19pm

Will there ever be an update for this wonderfull VST-i?

64-bit, VST3 all in the long awaited SQ8X???

2 December 2013 at 12:29pm

Unfortunately not :-(.

27 October 2016 at 2:32pm

I would pay money for that - because the 32-bit version crashes in Cubase 8.5 when using more as one instance :- (.

2 December 2013 at 12:37pm

That is so unfortunate....

17 February 2014 at 9:59pm

The read-me says...

  • Program change messages ignored.
  • When used with a sequencer, the only sound the host can save within the song file is the one in the edit buffer.

Does anyone know if those statements are actually true? If they are, its usefulness is extremely limited. If not, it'd be great. I still have an ESQ-M, not used a lot any more, but I really liked it back in the day.

18 February 2014 at 7:52am

I don't know... I never use program changes, and have never used more than one instance per song.

It's free and it sounds great, that's a lot of usefulness to me! But yeah it's too bad that it never got any further developement.

12 August 2014 at 9:31am

sign up.

27 January 2015 at 2:52pm

Hi, everyone.

I'm new here, and I have to say, I should have registered earlier. Great stuff here.

I love the SQ80 and the ESQ-1. And I bought a SQ80 because I totally fell in love with the sounds I heard in the german "KEYS" magazine, issue 08/2000, when they wrote about the machine in a vintage corner. I never managed to find those sounds, or reprogram them.

Does anyone of you by coincidence know, which sounds were used for this article? I would die for that information. So please, if anyone of you knows what I'm talking about, let me know, please. I'd be tremendously grateful.

Once again hello, and thanks to all of you! :)

31 August 2015 at 6:48pm

I know it's pretty much abandonware.. but any chances to install it using FL Studio 11/12?

1 September 2015 at 12:59pm

There are no installation files - just unpack the zip file in your VST folder. And yes it works with all versions of FL Studio.

4 May 2016 at 3:04pm

Lovely free VSTi! Very unique sounds from the 80s. It is really a pity it's abandonware now but still is a must have... :D.

9 May 2016 at 11:58pm

I just wonder where Siegfried went? He's done such a marvelous job with this. ESQ-1 was once my most beloved synth and I'm over the moon to have found this vst, which really feels fantastic and brings back pure joy to me. I'd just want to say "THANKS" to him and hope he's making an excellent and happy living with what ever he chose to do.

Now I shall make some nostalgic tracks full of original happiness, haha, and I hope he gets to read of my sincere gratitude and that of everyone else.

You Rock, Siggy.

11 May 2016 at 12:12am

I would also like a 64-bit version of VSTi.

Peter Widdicombe
Peter Widdicombe
13 October 2017 at 12:11am

My ESQ-1 finally "almost" died on me, but had exported the patches and can use them all in SQ8L.

However, now it seems many of the DAW's are abandoning 32-bit .vsti's... Didn't really want to get into the complication of external bridging. Yep, would like the 64-bit version of this useful synth vst.

5 January 2018 at 9:59am

Reaper has built in bridging.

31 January 2018 at 7:47pm

Hello, .

I think Siegfried Kullmann is dead. :(.


There are plenty of indications that this is the developer of the SQ8L, because of the man there is nothing to read for several years. Maybe he died of a serious illness.


31 January 2018 at 8:18pm

Awww, man, that's such a shame. I'm very sorry to hear that. I hope, somehow his soul still picks up on the love and appreciation we have for what he has created.

Thanks for letting us know, Marty.

Please log in to join the discussion

 My KVR - Version Control & Lists
Not In Your MY KVR Groups
(or group limitation prevents versioning)
163 people have added SQ8L / SQ8X to 18 My KVR groups 196 times
+12 in private groups

KVR Rank (Based on page views)

Overall: 25  24

30-Day: 23; 7-Day: 35; Yesterday: 40