Check out my music: http://caulixtla.com/music/

Is the Lexicon Alpha alpha?

November 24, 2015

The cheapest low-latency audio interface out there is the $30 Behringer UCA202. The UCA202 is a nice, albeit noisy (yes, the signal to noise ratio is 89db — but since digital noise is much more unpleasant sounding than wideband hiss, levels have to be carefully set) interface which is somewhat difficult to configure. The Lexicon Alpha, for $50, costs more than the UCA202, but it’s a much better interface.

First of all, the Lexicon Alpha comes with drivers on an included DVD which actually work out of the box; I easily installed them on my 32-bit Windows 7 computer which I use as a dedicated reverb unit. Lexicon also has drivers for 32-bit and 64-bit Windows 7 and Windows 8 on their Windows driver download page. Second of all, the Lexicon Alpha, once it has the drivers installed, is reasonably low latency, and is a much quieter and transparent interface than the UCA202 to boot. Furthermore, I appear to be getting less audio glitches with Lexicon’s driver then I did with Behringer’s driver.

The Alpha, nicely enough, doesn’t need an external power supply — it runs off of USB power. It’s pleasant to not have yet another wall wart to use this unit.

One only caveat is that, in my particular setup (hooking up the Alpha on the effect send of a Tascam Portastudio, and hooking up its output to inputs in the Tascam), there was some high pitched noise which I eliminated by placing an isolation transformer (the $65 JK Audio Pureformer) in the signal path. One can argue that this makes the Alpha a $115 instead of a $50 audio interface, but the transformer can be used to solve other issues where ground loops are causing noise, there are more inexpensive transformers out there (the Rolls HE18, for example, is available for $38), and the noise only appears when connecting both the Alpha interface’s input and output to the same device.

Its latency claims to be as low as 5.3ms each way — a round trip time of just over 10ms. The actual round trip latency (RTL) at the fastest possible settings is reported by RTL Utility as being pretty high: 17.5ms; I measured 19ms, but that includes the D/A and A/D latency of my Tascam DP32SD. This is fine with simulated large halls but the latency is too long to add a small room reverb to a percussive sound unless another reverb provides some wash during those first 19ms. For recording, the Alpha compensates for this latency by allowing one to directly hear the input they are recording while monitoring other tracks.

The Alpha has input and output level knobs, and its signal to noise ratio is high enough that it can be used without careful gain staging. That said, while low, the noise the Alpha generates is an unpleasant digital whine. As strictly an audio interface, it’s a good sounding cost effective solution, as long as its 17.5ms latency is OK. The latency is too high to use this interface in a computer which is a dedicated reverberation processor; I ended up using a Focusrite Scarlett 2i2 instead when it was 33% off ($100 instead of its usual $150 price) on Black Friday 2015.

Note that, while it has an XLR input, the Alpha does not provide phantom power for condenser microphones. Also note that its footprint is bigger than the tiny Behringer UCA202.

The included software

In addition to being a nice interface, it includes an OEM version of Steinberg Cubase and a VST reverb plugin called “Lexicon Pantheon.” The Pantheon plugin, annoyingly enough, only works with the Cubase host; yes, it has code to deliberately lock it out from other VST hosts.

The included copy of Cubase 5 LE is a pain to install: I had to install Cubase, install the DRM manager, sign up for an account at Steinberg’s web site, uninstall Cubase, install a newer version of the DRM manager, and finally install Cubase again. Not to mention entering a code from the DRM manager in to Steinberg’s web form and getting an activation code back. All of this requires the computer to have an active internet connection while activating the software, but the internet connection can be turned off once the software is activated.

The entire ordeal has convinced me to, once I go the DAW route, to use Cakewalk Sonar, which does not encumber the user with copy protection.

Once I got Cubase running, and figured out how to start plugins, I compared the Pantheon plugin to my go to reverb, Valhalla Vintage Verb. The difference is like night and day. The Pantheon reverb is one of those reverb plugins from the mid-oughts (first 2000s decade) where plug in designers did everything they did to minimize CPU usage so Pentium III users did not complain about their plugins using too much processing power. The reverb has what reverb designers call “low modal density” which means, in plain English, that it doesn’t sound good. Long reverb tails sound like feedback loops, not reverberant washes. These days, even free VST reverbs like Signal Dust’s Abstract chamber sound a lot better. Heck, the simple one-knob reverb included with the Alpha’s version of Cubase sounds better than the plugin Lexicon includes.

Valhalla Vintage Verb can be run in Cubase and sounds quite nice.

I did not get a chance to use Cubase LE as a multitrack recorder and/or MIDI sequencer, but it appears to be pretty good performing either function. The only hassle is the onerous install process because of Steinberg’s DRM.

Considering the quality and price of the hardware, the included software is icing on the cake, so I don’t consider its limitations a significant liability.

In summary

The Lexicon Alpha is worth getting. It’s a nice sounding low-cost audio interface; its weakest feature is, ironically considering it’s a Lexicon, the Pantheon reverberation algorithms. The interface may also need to be connected to an isolation transformer for noise-free operation. Those caveats aside, this is an interface I can use day to day.

I would give this interface five stars — I do not think an interface at this price point needs any software beyond basic drivers — but am taking off one star for needing a transformer to have it be quiet enough to work in my setup.