"If you want classic Fender tube tones, the Blues Junior IV remains among the cheapest ways of achieving them." We review the Fender Blues Junior IV tube amp

The Fender Blues Junior IV is one of the most popular tube combo amplifiers the world has ever seen, positioning itself as a compact and easily transportable unit that boasts enough power for live playing and recording scenarios. Its fourth iteration, originally released in 2018, was about evolution, not revolution for Fender, looking to make incremental gains on predecessors, rather than reinventing the wheel.

The Blues Junior IV has always faced pretty stiff competition, namely from cross-Atlantic contemporary, the Vox AC15 – an amp that goes almost beat-for-beat with the Blues Junior in terms of specifications, and is one of only a handful of amplifiers in this category that can claim to come close to matching the pedigree of the Blues Junior.

Alongside the Vox, there are amps from Marshall (DSL and Origin series), Orange (the Rocker 15), and plenty of others that sit at comparable price points and have similar power. Despite all of this, the Blues Junior has regularly sat at the top of the pile in terms of sales figures in its class, regardless of the competition. It is the amp to beat.

The Blues Junior IV comes loaded with 15 watts of all-tube power courtesy of three 12AX7 preamp tubes and two EL84 power amp tubes. It puts this power down through a single channel, with a narrow set of controls: volume, treble, bass, middle, master volume, reverb, plus a FAT switch.

The reverb is a genuine spring tank, rather than the digital emulations that have become ever more common in small tube amplifiers due to space, reliability, and the quality of digital reverbs nowadays.

All of these sounds are projected through a 12” Celestion Type A speaker, a ceramic magnet design that boasts 50 watts (RMS) of power – more than enough for the Blues Junior – and is designed for "modern American" tones, with a punchy low end and articulate midrange, designed for achieving those classic Fender clean amp sounds.

My first impression when taking the amp out of the box was that it was a serious piece of kit. Some amps I have played over the past few years – even some that would position themselves as competitors to the Blues Junior – feel as though they are made to a price point, rather than to a specific standard, but this is not at all the case here.

The Tolex used feels suitably rugged, ready to take on any kind of environment, and I could find no noticeable areas where it was loose or sagging. If I had to nitpick, the fact you can see the joins where a couple of different pieces of Tolex panels have been used means it’s not as totally sleek as it could be, and in the back cavity there are a couple of areas where you can see the staples used to hold the vinyl down, but this is looking for faults and not something that anybody would notice unless actively hunting for issues.

The grille cloth is the classic Fender silver, with a tight weave that you are unlikely to pierce. It’s timeless, having first appeared on their amps in the late 60s, and it still holds up today. The same can be said of the aesthetic of the Blues Junior in general, and if you were to put an original Mk I Blues Junior next to the IV, there’s a good chance you wouldn’t be able to tell which one was which. Personally, I have no problem with this at all, and appreciate that Fender has found a functional and handsome design and stuck with it.

The steel-reinforced carry handle self-recesses down against the amp when not in use, but is easy to access when you do want to grab it. On handles like these on cheaper amps, I have found that the plastic coating around the handle can split over time as the material begins to become brittle with age, but this feels suitably durable, and there are no signs of a seam that could split after significant use.

The chicken-head style, pointed knobs are timeless, and have a solid travel to them. Comparing directly to those on my Vox AC4, which has almost identical-looking knobs, the Fender is fractionally firmer in operation, which I generally like, though not by any significant margin.

While it’s not strictly a budget amp, it sits towards the bottom of the tube amp market, so accessories aren’t necessarily something to be expected, which makes the addition of a footswitch as standard welcome. The footswitch itself is vintage-inspired, and it has a build that can take a serious stomping. I’m not a particularly small guy, and it dealt with my boots crashing down on it with no issues whatsoever.

The only potential negative is the shape, which is circular and not optimized for slotting onto a pedalboard. If this is something you’d like to do, there are a number of aftermarket switches that can be swapped in and are more pedalboard-friendly. There’s also no cover included as standard, but you can purchase one from Fender or find 3rd party option easily online.

While I haven’t had the opportunity to gig the Blues Junior IV, I’ve done my best to replicate the gigging experience by loading it in and out of the car and on short drives. I live around a number of country roads with potholes aplenty – the Blues Junior has not been treated to smooth rides. In my testing, it came out entirely unscathed and worked perfectly, which is not something I can say for other tube amplifiers I have used.

One of the first things that struck me upon the amp's arrival at my door was just how small it is. When I think of 1x12 combos, I tend to think of amps like the Blues Junior’s big brother, the Hot Rod Deluxe, or a Marshall DSL40 combo – both of which are significantly larger – and, maybe it’s purely down to the space in my home, but I absolutely loved having a compact amp.

When I wasn’t using it, it was easy to find space to stow it away, or a corner of a room that was actually improved by having this little amp positioned in it. It’s only 16 inches high, 18 inches wide, and between 9-10 inches deep, and comes in at around 30lbs/14kg, which means it is light enough to carry for most players, particularly if you’re just moving it around the home.

The Blues Junior IV is extremely simple, so if you’re expecting modern features, you’re definitely looking in the wrong place. The FAT switch is footswitchable, and I like that the labels face you as you approach the amp from the front, which was not the case on earlier iterations of the Blues Junior.

For home use it does edge towards being too loud, at least if you want to get it properly singing. I live in a semi-detached property with a young family next door, and I was acutely aware that pushing the master volume knob past the 3 or 4 mark would make their walls vibrate. If your home is detached, or you are lucky enough to have a sound-insulated home studio, you can probably make it work, but for those in apartments or with shared walls, I’d look at something like the Marshall DSL1CR or the Blackstar HT-1R.

While it would feel criminal to start lumbering it with things like a USB output or a headphone jack, an effects loop wouldn’t go amiss. The one thing I found it seriously lacked was switchable wattage, something many of its rivals have. 15W may not sound like a lot on paper but this is still a tube amp. For home use, switching it down to half, or 10% power, would be so useful, without negatively impacting the amp or spoiling its character at all.

To start with, I plugged in sans pedals to get the pure, natural tones of the Blues Junior IV. My immediate take was how instantly dynamic it feels to play, with an organic response to subtle changes in my playing. Dialling up the preamp volume, I can get a bit more dirt, but when I roll back my volume knob, things go from warm overdrive back to bright and clean.

On my Les Paul, which has a volume knob for each pickup, I found I could set the neck pickup volume to around halfway and get warm rhythm tones, and then switch to the bridge, on full volume, and have some crunchy lead tones ready to go. Unsurprisingly, with the pokey humbuckers in the Ibanez, the amp was even more grunty, and the natural tube breakup was particularly delightful.

When I used my Fulltone OCD overdrive pedal, it helped push that overdrive into cascading, harmonic distortion even on subtle settings. As I took things further down the dirt road, I wasn’t surprised to find that when I started stacking fuzzes, I quickly reached the ‘fart-out’ zone, where the amp struggled to cope with anything more. While stacking an EHX Big Muff and Dunlop Gypsy Fuzz isn’t really something I’d regularly do, it was more about pushing the limits of the Blues Junior IV, so I can’t hold that against it too much.

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The ‘FAT’ switch, which is operated on top of the amp or via a foot switch, engages a boost in the midrange, which results in a more pronounced thick tone, ideal for soloing. It’s not quite like switching in a Tube Screamer-type pedal, but that doesn’t mean it isn’t a noticeable and effective way to get a tone boost.

The integrated spring reverb in the amp is classic Fender, and just delightful. It has just the right amount of that trademark ‘drip’, and is a noticeable upgrade on the previous generation’s spring reverb, which had a slightly harsh quality. Personally, I prefer the voicing of the reverb on the IV versus the prior iterations. If you’re looking for cavernous ambience, that’s not quite what’s on offer here. It is more subtle, particularly between one and six on the knob, although it can go into a more swampy, drenched style as you go beyond this point.

Next, I used an MXR double team of a Carbon Copy analog delay pedal and an MXR M300 reverb pedal, with a Boss chorus pedal thrown in for good measure, to push the Junior IV into larger, more spacious tones. The Blues Junior held up well to this, particularly when playing with my Gold Foil-equipped Supro, though the inherently warm nature of the Carbon Copy did mean the amp felt a little dark, which I quickly remedied with a few EQ tweaks.

The lack of an effects loop means your time-based effects can get muddy when you start going for more overdriven sounds from the amp itself, as your entire signal chain is being subject to preamp gain. This went into shoegaze territory for me, which I rather liked. I can see this being more of a problem if you use a lot of overdrive/distortion pedals in tandem with ambient time-based effects, as things could get a little muddy when that kind of signal chain collides with a hot preamp section, though, for my style of playing, it really wasn’t a problem.

Having lived with the Blues Junior for a decent period, I still think it’s a great amp for anybody likely to find themselves regularly gigging, offering just the right combination of volume and transportability for the vast majority of shows. It’s also a simply phenomenal studio workhorse, taking up minimal space, but producing maximum tone at a very reasonable price.

In an ideal world, it would be a little bit lighter, but some extra weight is a tradeoff I am more than happy to make for the Celestion Type A Speaker, the spring reverb tank, and a robust wooden frame. While the Blues Junior is designed to be a simple, stripped-back, and authentic tube amp affair, I can’t help but feel that there are simply some things that the Blues Junior IV is falling behind on. Cab-emulated DIs and an effects loop are now staples in the modern era of small combo guitar amps, and the Junior IV shows its age here.

I’ve gone back and forth asking whether $789 is a reasonable asking price for the Blues Junior, particularly when you compare it to the likes of the Supro Delta King 12, which has similar features but comes in over $100 cheaper. Something like the Vox AC15 – an amp most definitely in the same class as the Blues Junior – is even more expensive. It’s not an insignificant investment, but in the context of modern tube amp prices, it’s worth it, and when compared to the competition, it’s competitively priced.

Guitar Player verdict: If you want classic Fender tube tones, the Blues Junior IV remains among the cheapest ways of achieving them. Some may wish for a few more mod-cons, but you have to respect that Fender has stayed true to the recipe that made the Blues Junior a fan favorite since its release. In a few years, maybe this will change, but right now, and as has been the case since it launched, the Blues Junior is best in class, even if that class has a lot of competition.

Specifications

• Price: $789.99 | £749.00 | €755
• Type: Combo
• Origin: Mexico
• Output: 15 Watts RMS
• Speaker: 1x12” Celestion A-Type speaker, 8 ohms
• Channels: 1
• Controls: Reverb, Master, Middle, Bass, Treble, Fat Switch, Volume
• Connectivity: 1x 1/4" Input
• Footswitch: 1-button footswitch (included)
• Weight: 31.5 lbs (14.3 kg)
• Dimensions: 457.2 x 406 x 249mm
• Contact: Fender