AF’s Weblog

January 5, 2009

Test: Zoom ZFX Stack Package Review

Tube or not tube
Zoom Stack Package: The Test

Though the concept may not be original, Zoom has come out with an interesting interface that provides guitarists and bassists with an intuitive software/hardware setup, but with a twist: an integrated vacuum tube. In recent years there have been quite a few interface choices for guitarists and bassists, especially from line 6, but Zoom’s take on this combines amp modeling software with a USB audio interface featuring a Hi-Z input with a vacuum tube. Let’s take a closer look…

Vue générale

The S2t interface comes in the form of a vintage looking mini amp-head (222mm x145mm x82.5mm). The whole thing seems well made and robust (1.1kg). The knobs neither feel nor look cheap, and have just the right tightness for precision tweaking, though they are a little crowded, making it difficult to not touch an adjacent knob while turning one of them. All the input and output jacks also look and feel solid. Basically it’s a device that seems built to last, especially when compared to its competitors.


The ZFX package includes the S2t interface and the ZFX plugin. Installation on Windows XP proved to be fairly easy and hassle free. This interface apparently also installs easily on Mac OS X and Linux systems without any drivers needing to be installed*. Be aware, though, that the included ZFX software will not work on those systems, only Windows. This is why Zoom included Guitar Rig 3 LE in the package, and not because they thought their software wasn’t good enough, as some might assume. Zoom also kindly included Steinberg’s Cubase LE4 for those in need of a DAW.

Vue générale

I wanted to see if the interface and software would work on a less powerful PC so I installed it on my old laptop (Windows XP SP2, 512 MB Ram). Apart from a few graphic issues (my card is no doubt a little too old) the interface and software worked perfectly once I correctly configured my audio settings in my DAW (Sonar). I was able to get very low latency (1ms) which surprised me from this USB interface.

There are two pdfs (startup & manual) as well as two very light printed startup guides included. The problem with these guides is that they focus mainly on installation and using the ZFX software (150 pages!). There’s next to nothing on the physical interface (the S2t) itself, nor on advanced settings. I had an issue with direct monitoring latency which was too long (around 15-20ms), for which I couldn’t find any information. I ended up testing all basic and advanced settings, finally finding the solution when I changed the buffers in the advanced section. It seemed pretty obvious after the fact, but there was no mention of buffers and their effect in any of the guides I read.

Let’s take a closer look…


Again, what’s interesting in this device is it’s versatility or modular aspect. You can, if you want, experiment with other tubes inside the S2t, and the ZFX software also offers a lot of flexibility in terms of combinations and editing. And though the ZFX plugin/standalone couldn’t be considered sonically superior to competitors like Guitar Rig or Amplitude, it isn’t quite inferior to them either, and offers some unique features. Of course the best thing would be for you to try it out yourself, especially if you want to test it against Guitar Rig. You might just find that you like it better. But even if you find the ZFX software not to your liking, the S2t interface still has much to offer. At around $190 (about the same price as the Line 6 UX2) you get a robust and relatively stable guitar/bass oriented interface with low latency and pretty good sound quality. The Hi-Z feature is an interesting plus, though nothing revolutionary. The integrated tube will not convince everyone, but the fact that it’s USB powered should make it more appealing to Home Studio enthusiasts on the go.

Solidity: the interface, its knobs, and connecters
Nice look
Hi-Z Concept – integrated vacuum tube
Flexibilty and modular aspect of both interface and ZFX software
USB powered

ZFX GUI is a resource Hog
Manuals hardly deal with the S2t
ZFX plugin only works for Windows-based PCs

Read the full Zoom Stack Package review article.



  1. Anyone using this?

    Comment by Tracy — February 27, 2009 @ 9:10 pm

  2. yes, I am using this and am very happy about it. Considering the money I spend on it it is fantastic as it has Cubase 4LE in it. So in one buy I had a workable studio environment, ready to go.

    Comment by tunc — June 26, 2009 @ 11:16 am

  3. please show me how or what i have to do to get the zfx plug-in working on my macbook pro cubase and guitar rig work but i need this to work it was expensive i need help please.

    Comment by anthony mavros — April 10, 2011 @ 4:39 pm

  4. will this work with Windows 7?

    Comment by thomato — July 19, 2011 @ 12:56 pm

RSS feed for comments on this post. TrackBack URI

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

Blog at

%d bloggers like this: