JP's Gear Review v2.0 - Ep.4 - The Bassbreaker Saga

 


A few months ago, I purchased a new guitar and an amp to go with it. What originally started as a simple transaction suddenly became disappointing, unsatisfying, and filled with buyer's remorse. Here's what is now know as The Bassbreaker Saga™.

Big shout-out to Katherine and Stéphane from Long & McQuade in Longueuil for their continued support in trying to get the Bassbreaker up to par, and finally exchanging it for something that will hopefully be better. Thanks a lot, it's very much appreciated!

What is the Bassbreaker?

The Fender Bassbreaker 15 is an all-tube(ish) amp introduced in 2016 to rather unfavorable reviews. Plagued with issues from the get-go and Fender barely acknowledging any of them, it was not off to a great start. Hopefully they fixed most of the issues in the last 6 years, right? Right...

To understand where this amplifier comes from, we have go back to the early 60's. Fender's most popular amp at the time was the Bassman. However, this particular amplifier was extremely difficult to find across the pond and it was also very expensive. A certain English businessman with a very familiar named managed to get his hands on one, reverse-engineer it, and make his own version. After 6 attempts, the JTM-45 came out of James Marshall's newly founded Marshall Amplification production lines in 1962. The JTM-45 was dubbed by Pete Townsend as "The Marshall Sound".

The Bassbreaker is a nod to that history, where its circuit incorporates the best of both the Bassman and the JTM-45. Sort of.

The circuit

The documentation states it's an all-tube amplifier, but I'd qualify it as an hybrid due to the ridiculous amount of TL072 opamps ICs in the signal path (there's 5 of them in total). It has a Structure knob, which allows you to select the number of preamp stages the signal goes through, an XLR output with cabinet emulation and ground lift, an effect loop, and a digital hall reverb.

From the input jack, the signal goes through the preamp tubes then to the tone controls. How many gain stage the signal goes through depends on the Structure knob:
  • Low: 2 gain stages; V1-A and V2-B
  • Medium: 3 gain stages; V1-A, V2-A, and V2-B
  • High: 4 gain stages; V1-A, V1-B, V2-A, and V2-B
The Master volume comes next, and its wiper is coupled to the effects loop's circuit (U1-A, U1-B, and U2-A). The output of the effects loop is then routed to opamps U8-A and U8-B to be conditioned for the digital reverb (which uses at least one opamp IC). The reverb output is then routed to its very own potentiometer to control the wet signal level for the dry/wet mix.

Now, both the effects loop and reverb output are sent to yet another opamp to be summed (U2-B) to create the actual reverb dry/wet mixed signal. The non-inverting output of U2-B is then sent to a JFET to kill the signal going to the power amp when Mute is toggled.

I'll ignore the line out/XLR output as it's not relevant here, but it uses both halves of one more opamp IC to do its thing. This output is always enabled even when Mute is toggled.

The output of the summing opamp goes through one 12AX7 phase inverter tube (V3) that feeds two EL84 power tubes in push-pull configuration (V4 and V5). Both power tubes are cathode biased to about 40mA. The output of the power tubes goes through an output transformer that provides 4, 8, and 16Ω impedance for speaker connections, selectable through a selector switch. There is one internal speaker connection and one external speaker connection.

Note: the service manual numbers the tubes the opposite way the signal goes through them, i.e. power tubes are V1 and V2, phase inverter is V3, and preamp tubes are V4 and V5, V5 being the first tube the signal goes to. I have no clue why it's like this.

The good things

It has a few things going it.

Output power

It's a small 15W combo that packs a punch. That thing can get really loud. However, it's clean headroom is very limited. It's a great amp for crunchy blues, rock, and - with high-output pickups and the gain cranked to the max - it can give you a good hard rock distortion. It is very versatile, and the 15W output is plenty enough to practice in your bedroom or woo your romantic interest in their living room. 

It look awesome

The grey tweed Fender used on the cabinet looks absolutely fantastic. It's reminiscent of the tweed-ish material used by Sears on their Silvertone line of amps back in the 60's, except it's Fender tweed dyed grey. The control panel and the knobs are simple and modern. It's a very stylish and modern amp.

Multiple levels of gain

Although not quite a novel feature per se (the same thing is present in a different form on the Hot Rod amps), being able to select how many stages of gain the signal goes through is great. The way it is done on the Bassbreaker is a tad confusing, but it achieve the same goal as the Hot Rod's Drive and More Drive toggles.

It sounds good (well, good enough)

Overall, the amplifier sounds good. In a simple setup with just the guitar and the amp, it will sound fine and it will be plenty versatile for everyday playing. You can dial in a bunch of tones ranging from a bright clean to a heavy overdrive. Depending on which features, settings, and gear you use with it, you might run into problems, but in simple scenarios it's a good little amp. It performs adequately for its intended use.

It has lots of features for an interesting price

This tube amplifier is about 1000$CAD. It has 3 possible gain modes, a reverb, an effects loop, an XLR line out right after the preamp section with a ground lift AND a cabinet emulation, an external speaker jack, and it has a grey tweed covering. Finding a 15W amplifier with all these features at this price point is nearly impossible. These features make the Bassbreaker a little Swiss army knife for your home recording studio.

Opinions on the circuit and issues encountered

My opinions on the circuit and the amp in general are mixed. I tested both the original amplifier I purchased and the replacement Fender sent me, and both showed similar behaviours.

It has a lot of interesting features for its price point, and it sounds great and performs adequately in specific scenarios, BUT...

Hot hot...

The output tubes are biased really hot, the preamp tubes are really bitey, and it makes the amp break up really early. This can be good or bad, depending on your point of view. With stock 12AX7, I cannot plug a guitar with humbuckers and set the Structure knob higher than Low and put the gain higher than ¼ to ⅓ of the way up, otherwise it overdrives straight away. The clean headroom is really limited. As a fan of the Fender clean tone, this is really limitative.

The amplifier in general is problematically hot - not just signal-wise - and is barely usable with anything other than low-output pickups. To get it to be somewhat usable, I had to replace the preamp tubes with 5751, which still had too much gain for two of my guitars, and change the output tubes to a matched pair of 7189 which give substantially more clean headroom before they start to overdrive and distort.

When in operation, the chassis will become really hot. Not "the tubes are radiating a bit of heat" hot, I mean "60℃ and then some, can't put your hand on it" hot. I triple-checked the power tubes, and they do not red-plate (although red-plating with the stock tubes is an issue in some amps). An infrared thermometer measured both EL84 tubes to be anywhere between 90℃ and 115℃ when in operation which is about how hot they should get, but the lack of ventilation makes all the heat radiate upwards on the PCBs and the chassis. This could cause some components to fail early and cause all sorts of other, hard to diagnose issues.

Clean is not so clean (but it's good)

Related to the hotness issue, is the quality of the clean signal: it is not really clean. It's clean enough, but there's always a little je-ne-sais-quoi. It's one of the things that drew me to that amplifier in the first place; the slight imperfections in the signal when the amp is not even close to overdriving. Changing the tubes had an impact on that (obviously) and now these imperfections are not as harmonic as they were previously. On the other hand, if I don't change the tubes, I can't use the amp with most of my guitars... Making the amp usable changed one of the selling points of that amplifier and, although expected, it's still a bummer.

The brightness

EL84 tubes are bright, that's a given. Compared to 6L6 or KT88, they are very shimmery. In the Bassbreaker circuit, these tubes are extremely bright, and the bright switch doesn't do much. The output lacks mid-frequencies, and even with an EQ pedal, it still sound pretty thin. It has an "OK-ish" bass response, but overall it's very middle-of-the-road.

In comparison, the Fender Blues Jr. - that also uses EL84 power tubes - sounds a lot more full, and rich, and clean. It's a very different circuit, sure, but it also sounds completely different. There is a way to make bright tubes sound full.

All the noise

I understand this is not a 3000$ point-to-point, hand-soldered amplifier with tube-driven spring reverb and that there is a need to resort to opamps for the effect loop and a digital reverb to keep costs down. The Hot Rod Deluxe and the Hot Rod DeVille both use opamps to drive the reverb tank and preamp out/in circuitry, and it works really well with no to minimal noise being introduced. I'm not sure what went wrong in the design of the Bassbreaker, but the features using opamps seems to be introducing a lot more noise than they should. The overall noise floor of the amp is a lot higher than the aforementioned Hot Rod Deville, which makes its overdrive sound really harsh, and in some case it will affect the clean sound as well. I suspect there are issues with some components interfering with each other or unshielded wires used when shielded ones should have been used.

The first Bassbreaker I had in my possession was manufactured in February 2016, placing it early in the overall production. It was a transfer from a different store, and it must have spent the last 6 years gathering dust on the sales floor. All the amps manufactured before early to mid-2017 had severe issues with the effect loop being extremely noisy, even with only a patch cable connected. It is a known issue that they addressed in later production, and I managed to get a second amplifier that was "fixed".

The process to get it fixed was supposed to be simple. My sales rep contacted Fender the day I reported the issue, and Fender dragged things out for over a month. In the end, Fender replaced the amp entirely and I received one that was manufactured in June 2022. I was really happy to finally be able to use the effects loop on my brand new amp, but my happiness turned to confusion, sadness, and deception the more I tested the amp with my pedalboard and individual pedals.

The noise floor of the amplifier skyrockets as soon as  more than one pedal is connected to the effect loop. I tried every single pedal I own, rewired my pedalboard, moved the amp at the other end of my office, plugged the amp in a different circuit, but it does not accept more than one pedal. Even then, the only pedal that works as it should is my Boss TU-3 tuner. Any other pedal will cause the amp to be extremely noisy. I do not have this issue with my Orange Crush Bass 50 bass amplifier's effect loop (or with the effect loop of either the Hot Rod Deluxe and Hot Rod Deville I tried in store), so it's definitely an issue with the effects loop circuit of the Bassbreaker.

Another odd behaviour of the effects loop is that whenever an effect is toggled, it causes an ear-splittingly loud pop in the amp. I don't particularly like that, and I've never had that kind of issues in any other amp I've tried.

Of all the issues with this model of amplifier, the noise when using the effects loop is a showstopper. None of the pedals combination that I tried work as they should. The noise is just always there and it's absurdly loud. When I use the pedals in series with the guitar in the input jack, though, no issues. The main reason why I purchased this amp was the effects loops, and it's not working. The higher overall noise floor, although annoying, is tolerable. It's just the effects loop circuit that is wonky and does strange things.

The reverb

The reverb is nothing to write home about. It is flat and muddy. It's a digital hall reverb, but they could have done much better than this. It also adds more noise to an already noisy amp. I don't like it and I don't think it sounds good.

Early production issues

The Bassbreaker amplifiers that were produced in 2016 and early 2017 were full of issues. The main issue reported was, oddly enough, a noisy effects loop.

The first Bassbreaker I had suffered from this very problem. According to multiple threads on various forums, all filled with people complaining, the root cause of the issue is a ground loop caused by the send and return jacks both being grounded to the chassis. The official fix from Fender is to replace one of the jacks with one that is insulated and won't ground to the chassis. It works, but there are still a lot of customer complaining the effects loop is still noisy when pedals are present. My replacement amplifier still exhibits a noisy effetcs loop even with the Fender-approved fix.

Another issue reported is the amp being fairly noisy even at low gain. Neither of the units I had had this problem, but they were a bit more noisy than I had hope for such amps. There are so many possible causes for this that it's nearly impossible to figure out why there is noise without messing with the PCB and voiding the warranty.

Last but not least, red-plating on one or both of the power tubes has been reported on brand new amps within the first 6 months after purchase. This issue is still being reported from time to time. Either the poor quality of some components, the lack of ventilation from the heat generated by the tubes, craftsmanship issues during assembly, or a combination of multiple factors are to blame. New amps should not be red-plating straight from the factory.

While post-2017 production runs addressed some of these issues, these problems still happen, and now some new ones popped up as well mainly related to noise. Although most new amps are relatively problem-free (for a while), the fact issues like these are still common occurrence 6 years later is concerning.

Summary

The Bassbreaker is a good entry-level amp, with a way-too-high mid-tier pricing. If you use it as it is intended to be used (that is with your guitar plugged directly in the amp, no effects loop, no reverb) it sounds great. It's a nice little 15W tube amp that gives you the warmth of tubes and great versatility. It's perfect for every day practice or as a beginner amp, but not much more. I feel like everything beside the preamp and the power amp was an after-thought.

Is it worth 1000$CAD, though? Absolutely not. At most, I'd pay 550$-600$ for this amp, all because of its limitations and shortcomings. The overall design and build quality is definitely not up to Fender's standards. It is a Swiss army knife that's OK-ish at some of the tasks it is supposed to be doing, and absolutely terrible for all of the others. The price tag they slapped on it makes it looks like it is better than it actually is. For the same price, get yourself a Blues Jr, or put 300$ more and get a Hot Rod Deluxe with a volume box (like the JHS Black Box) to put in the effets loop and tame it to bedroom-level volume output.

Although I like the tone of the amp and its versatility, I was utterly disappointed when the effects loop turned out to be completely useless. The stock tubes are also not great, and should be changed as soon as possible. A full set of tubes from The Tubes Store will set you back about 200$CAD and will make your amp sound 200% better.

I returned the Bassbreaker because of the effects loop and noise issues I encountered when simply testing the amp. I decided to go back in known territory, and ordered a used Hot Red Deville from my favorite music store for roughly the same price. I owned a Hot Rod Deluxe (which shares the same circuit as the DeVille) many years ago and I deeply regret selling it.

I am a fan of the Fender clean tone and never had such issues with any of the Fender gear I owned or played with. I'm really disappointed in the quality of the Bassbreaker amps considering they are 300$ shy of the Hot Rod Deluxe's price. I expected at the very least similar build quality and usability out of it, but it is sadly not the case. It's a great beginner amp with lots of tone and character, but that's about it. Push it slightly and it just farts out and start misbehaving.

The All-Important Rating™

Build quality: 5/10. The cabinet is solid and the speaker is good. That counts, right? The rest, well, it's debatable. There are obvious issues with the PCB design, the lack of ventilation for the tubes makes the chassis untouchable, and the overabundant use of opamps ICs are causing of lot of problems. The high noise floor is also indicative of other issues with the circuit or component placement on the PCBs.

Sound quality: 6/10. It sound great, as long as you don't try to actually use it to its full potential. The reverb is pretty bad, though.

Features: 4/10. It has many features, but none of them work right beside the actual preamp and power amp (and even then, you might have to tweak them). It would have been a 5 if a new tube set would not have been required.

Usefulness (2 ratings special): 
As it is marketed (mid-tier amp): 3/10. It's borderline useless, and the main selling points don't work good enough to actually use them for recording. It's infuriating as it is not a cheap amp.
As a beginner/entry-level amp: 7/10. It does what it says on the tin, and it does it adequately enough. Don't go on stage with it, though.

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