The Katana 50 MkII is a versatile combo amp packed with practical technology, including Boss' guitar effects processing.

At its core is a 50W amp with built-in power attenuator, which allows you to half its output to 25W, or go as low as 0.5W for quiet practice.

Built-in amp modeling allows you to choose between different voicings, from clean to lead, there's even a setting that's meant for acoustic-electric guitar. Although I do have to point out that if you're looking for a huge number of amp models to play with then this isn't the best option, but the models it has sound great.

In addition, the amp lets you utilize effects right on the amp, with over 60 digital Boss effects available via the amp's software editor. Unfortunately the software editor is a bit overwhelming at first, but if you take the time to understand it you'll get a lot more out of the effects.

This amp can go from practice to stage and recording use with its support for two external footswitch / expression pedals, 1/4" output and USB recording output.

With its power attenuation and versatile digital sound processing, the Boss Katana-50 MkII is very easy to recommend, particularly for anyone who doesn't mind having a large practice amp that's fully capable of gigging.

Specifications

• Power: 50W (25W / 0.5W Attenuation)
• Speaker: 1x12"
• Effects: Modulation, Delay, 60 BOSS Effects (Tone Studio software)
• Input: 1 x 1/4" (Instrument), 1 x 1/4" (PowerAmp), 1 x 1/8" (Aux)
• Outputs: 1 x 1/4" (rec/headphones)
• Weight: 25.6 lbs.

Positive Grid were previously known for their excellent 'BIAS' software modelling apps and that experience shines through here. The amps and effect models are quite good but the sound is hampered by the speakers sounding too bass heavy which often leads to a 'muddy' tone by default. There are ways to address this but it's a hassle to have to deal with. Not everyone find this a problem but many do including myself so be warned.

The Spark 40 aims for the look and feel of a small boutique amp and they've done a pretty job at making it home friendly as possible. You still have your classic amp control knobs for gain, Hi/Mid/Low and Master volume plus Mod Level, Delay and Reverb and you can store 4 patches in the unit.

The controls look pretty well organised on the top of the amp with about as many knobs as you could fit (10). There's an amp style selector and the usual amp controls (gain, 3 band eq and master) plus single knobs for levels of Mod, Delay, Reverb and Output (the real master volume). You can recall 4 patches via buttons next to a tap tempo button and these can also double as tuner lights which is pretty handy.

The control knobs on the Spark 40 amp itself.

They've done good job of making it look and feel like a classic amp here but there's only so much you can control this way. For more fine grained control of effect parameters or amp models you need to use the app. The problem you inevitably run into with this sort of setup is that of 'dueling' controls between the analogue knobs and the app or patch values. Short of expensive motorized knobs or led lights all over the place there really isn't a perfect solution which means that you are often operating blind when looking at the physical controls.

On the Spark if you twist a knob it will change that associated setting to the knob value and the app shows this is real time. This could result in a quick jump from it's prior value which could be nasty surprise if you are turning the gain 'down' from 9 when it has actually been operating at 2. Controlling the amp models and effects in the app is fairly straightforward. The signal chain is laid out as a virtual pedalboard with 6 effect pedal type slots and one amp model as below:

When it comes to the sound though there is issue that we need to talk about. It's divided users between those that don't hear it, those that don't mind and those that think there's a problem. For me, the moment I started playing through the amp the sound coming from the speakers was overly 'bassey' for electric guitar. You won't have to look far to find many others experiencing the same, describing it as 'Muddy', 'Muffled', 'Boxy', 'Wooley' and complaining about the lack of brightness. It's surprising for such small speakers really but they do put out a lot of low end and that can obscure the high end, particularly the high midrange that's so important for guitar. Personally I can still hear and appreciate the tones which do sound good themselves but alongside a certain 'rumble'. I found myself using the bridge pickup to get the same tone as the bridge/neck mix on my humbuckers and but that didn't quite work.

One of the highlights of the package are the features that allow you to play along with practically any song on YouTube with chords automatically detected and shown. There's also a 'Smart Jam' feature where you can play a short chord progression and it will add a bass and drum accompaniment as well as generic track for you to Jam with. This doesn't always produce great results but it can be handy. For fun I pulled up an old smartphone video of me and a friend at an open mic night playing an original song with less than 50 views on it and sure enough, after the first playthrough it produced an accurate rendering of the chords which is quite impressive!

If you're looking for a home friendly amp with a ton of sounds and practice options literally at your fingertips via the app then this is a great choice.

Specifications

• Power: 40W Class D
• Speaker: 2x4"
• Effects: 30 Amp models, 40 Effects
• Input: 1 x 1/4" (Instrument), 1 x 1/8" (Aux)
• Outputs: 1 x 1/8" (Headphones)
• Weight: 11.46 lbs.

Bugera is known for affordable tube amplifiers, and the Bugera V5 Infinium is currently rating well in the sub $300 price range.

This 5W all-tube amp houses a 12AX7 preamp tube and EL84 poweramp tube, with built-in power attenuation that lets you switch the power down to 1W or 0.1W. This built-in attenuation allows you to crank the amp at lower volumes, which means allowing for great tube tones at more room friendly volume levels.

Also worth noting is Bugera's Infinium technology which extends the life of tubes by making sure that the tubes are operating at their ideal parameters.

Low to mid-gain tones are where this amp shines, and as such, it works well with a wide range of musical styles. The ability to attenuate its output power down to 1/10th of a Watt is also an important for those that need that saturation at a more manageable volume.

The simplification of the usual tube amp setup is not without its compromises. For one, the lack of tone shaping limits the kind of tones you get from the amp. It's not about to let you go into super scooped metal territory either.

Despite these limitations, the Bugera V5 Infinium is a great entry point into the world of tube amps, the built-in attenuator also makes it a great bedroom / practice amp for those who want genuine tube tones at lower volume levels.

Specifications

• Power: 5W, 1W, 0.1W
• Speaker: 1x8"
• Effects: Reverb
• Input: 1 x 1/4" (Instrument)
• Outputs: 1 x 1/4" Internal Speaker, 1 x 1/4" Headphones
• Weight: 22.1 lbs.