Zoom G2.1u review
When I was getting serious about playing guitar, I was on the lookout for a nice (and affordable) multieffect device. I came across a lot of different brands and a price range from 50 Euros to 1000 and more. Then the local guitar shop owner showed me the Zoom G2 family. And for about 200 Euro (it's much cheaper by now, in fact there is a successor, the Zoom G2.1Nu) I got a versatile multi effect with usb recording options and a decent delay of under 5ms when switching between effect presets.
This thing looks a bit cheap at first sight but it is almost 100% metal. The housing is thick metal, the pedal is metal, the two footswitches are metal, only the knobs and a few design elements are chrome-like plastic. The overall form of the device gives it a bit of a toy-look. But its definitely not a toy... Well not only.
So what can be seen on the outside? The obvious parts are the pedal, the footswitches and a few knobs.
Just to summarize: 1 pedal, two footswitches, 4 knobs, 6 buttons. The specific functions will be described later.
On the backside there is a plastic cover with the input jacks. From left to right there are a usb port, input, output, control in (for an optional foot switch or expression pedal), the power switch and power input. The G2.1u comes with a 9V PSU but it can also be powered by 4 AA batteries. The battery compartment is on the underside. When plugged into USB it draws its power from the USB.
This stuff is very much copied from their website:
Effect Types: 54
Effect Modules: 9
Maximum Simultaneous Effects: 9
Patch Memory: User 40 + Preset 40, Total 80
Sampling Frequency: 96kHz
A/D Conversion: 24bit, 64times over-sampling
D/A Conversion: 24bit, 128times over-sampling
Input: 1/4" phone jack(Rated input level: -20dBm, Input impedance: 1MΩ)
Output(Line / headphones combined) : 1/4" stereo phone jack(Maximum output level: +5dBm, Output load impedance: 10kΩ or higher)
Control Input: Expression pedal, Foot switch
USB: Type B(Based on USB1.1)
Display: 2digit 7segment LED display, Parameter LED, Pedal assign LED
Power Requirements: AA size(LR6)battery x 4, or AC adaptor DC9V/300mA/ Center minus type(AD-0006 recommended)
Battery Life: 7.5hours(with alkaline batteries)
Weight: 1100g (without batteries)
Optional Accessories: FP02(Expression pedal), FS01(Foot switch)
What can it do?
Besides any technical specification or the look of the device, the most important thing is what it actually can do. Roughly said, it can tune, it can combine effects and it can act as a recording interface.
The tuner is switched on by pressing both footswitches simultaneously and can also be used in muted mode (press the switches longer). It is chromatic and shows the current note and how far it is off. Its a tuner, what else can i say about it???
The G2.1u can use all of its 9 effect modules at a time. The modules are
Its a simple compressor module, that can be adjusted in sense, level and attack.
Wahwah / Effect
This module combines a wide range of wahwah effect, some filter effects and other stuff like phaser effects.
Here you can choose from different Noisegate types to reduce the noise in your input signal. Besides the two noisegate types it has a zoom noise reduction thing that dynamically reduces noise while playing.
All sorts of distortion and overdrive effects are in this module. It can emulate the sound of some old amp combos or famous distortion pedals like the metalzone or the fuzz face. A nice addition is the acoustic simulator.
A threeband equalizer.
Extra Equalizer / Cabinet / Mic
Three more bands for the equalizer and a wide range of cabinets and mics the G2.1u can simulate.
Modulation / SFX
Modulation effects like pitch shifter, chorus and vibrato are in this module.
Delay, ping pong delay and echo with hold function.
Hall, reflection and multitap effects.
Besides these options the module chooser knob has the position control in which you can adjust which effect module is affected by the expression pedal. Since the part of the effect that can be varied is different for each setting, a short glimpse into the manual is always helpful.
There are 80 banks for effect presets in the device of which 40 are for user presets and the other 40 are always reverted to the factory presets.
For the recording part it comes with Cubase LE. An older version that has some problems with Windows Vista. It is a good advice not to use the ASIO driver that comes with the software and instead use the ASIO4ALL driver you can find on the internet.
One thing worth to mention is the built in drum machine. It has 40 more or less usefull patterns that you can not change. The range goes from simple click and 4/4 to some weird jazz stuff and some double base metal rhythms.
For more informations check the manual: 
What does it sound like?
So this section is totaly my own opinion, and based on my equipment, my ear and my knowledge about sound. :)
This thing sounds really good considered its low price. The sound quality is flawless and the simulated cabinets give a great range of sounds additional to the huge amount of combinations you can choose with all those effect modules. I mainly used the distortion module with some chorus and reverb but the overall performance is great.
The only thing i noticed is that in comparison to my boss pedals this thing sounds a little bit "plastic". It's just a small hint that this is a multieffect that just models everything with a digital processor but in my opinion you can hear that, but only if you put both next to each other and can hear the difference.
One problem with earlier multieffects is gone by the way: the long switching time. With the G2.1u it is barely noticeable that there is a gap. It's not longer than the sound of a switching single pedal.
Do I recommend it?
Definitely yes, maybe I would advice to buy the successor but in general it is a great multieffect for affordable price. It can be used with a small amp, a fullstack or on stage. Also it is possible to use headphones with it for quiet home practise. Simply versatile. The ambitious player should test if he doesn't mind the small hint of digital processing in the sound.
Review by Twist