If you are shopping for your first “proper” practice amp in 2026, you have almost certainly narrowed it down to the same three names everyone else has: the Boss Katana, the Fender Mustang LT and the Positive Grid Spark. I have played all three in shops, at friends’ places and in my own flat, and I have read more owner threads about them than I care to admit. They are all good. They are also very different animals, and the “best” one depends entirely on where and how you play.<\/p>\n
This is not a spec-sheet dump. I already wrote a long piece on what Katana owners actually say after a year<\/a>, and a broader guide to the best amps for home practice<\/a>. Here I want to put the three head to head on the things that decide the purchase: tone, the app, usable power, headphone playing and price.<\/p>\n One note before we start: Boss has moved the Katana to a Gen 3 version, Positive Grid has released the Spark 2, and Fender’s LT range sits alongside the pricier GTX. I will point out where the older models (Katana MkII, original Spark 40) are the smarter used buy.<\/p>\n A 50-watt combo with a 12-inch speaker, five amp characters (clean, crunch, lead, brown and acoustic; Gen 3 adds a “pushed” voicing), a wall of Boss effects you edit from the free Tone Studio software, a power control switch (0.5 W, 25 W, 50 W) and a headphone\/recording output. It looks and feels like a real amp because it is one.<\/p>\n The LT25 is a 25-watt, 8-inch combo with a small colour screen, 20 amp models and a bank of effects you scroll through on the amp itself or edit over USB with Fender Tone LT. The LT40S is the stereo desktop version with two small speakers, aimed squarely at the bedroom and the desk. Both have a headphone out and an aux input.<\/p>\n The Spark 40 is a 40-watt stereo desktop amp with two 4-inch speakers, four preset buttons on the top panel and an app that is the real product: Bluetooth tone editing, a huge library of shared presets, Smart Jam backing tracks and Auto Chords. The Spark Mini is the battery-powered, 10-watt travel version of the same idea. The Spark 2 is the current flagship, but the original Spark 40 is still on sale and heavily discounted.<\/p>\n Let me be blunt. In a room, at rehearsal volume, the Katana-50 wins. The 12-inch speaker moves air, the brown channel does convincing hot-rodded Marshall territory, and the clean is genuinely usable for jazz or country. What comes up again and again in owner threads is that the Katana “feels” like a tube amp under the fingers in a way the small desktop boxes do not.<\/p>\n The Mustang LT25 is a fine-sounding amp for its price, with the Fender cleans you would expect and a few good high-gain models, but the 8-inch speaker gets boxy when you push it. Its strength is simplicity: turn the knob, pick a preset, play.<\/p>\n The Spark sounds spectacular on your desk and through headphones. The stereo image and the wide speaker voicing are flattering, and the modelling is excellent. Push it in a room with a drummer and it falls apart, because that is not what it is for. The Mini is a genuinely fun couch amp and nothing more; do not expect it to keep up with an acoustic guitarist, let alone a band.<\/p>\n This is where the three really diverge.<\/p>\n Amp wattage numbers are marketing until you understand what they mean for solid-state combos, which I cover in guitar amps explained<\/a>. In practice:<\/p>\n All three have a headphone output that mutes the speaker. Through headphones the Spark is the most enjoyable, the Katana is the most neutral, and the Mustang is perfectly fine.<\/p>\nThe three contenders in one minute<\/h2>\n
Boss Katana-50 (MkII or Gen 3)<\/h3>\n
Fender Mustang LT25 and LT40S<\/h3>\n
Positive Grid Spark 40 and Spark Mini<\/h3>\n
Tone: the Katana still sounds the most like an amp<\/h2>\n
The app and the workflow<\/h2>\n
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Power, volume and headphones<\/h2>\n
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Comparison table<\/h2>\n