From the giant, hefty beasts of yore to their modern, ultra-portable equivalents, bass amps have come a long way. So, what's next?
Bassists are often quite well-informed about the details of their instruments, down to the finest technical specs. Many of us have had our share of intense discussions about the most minute differences between one instrument and another. (And sometimes those are interrupted by someone saying, "It's all in the fingers.") But right behind our backs, at the end of our output cables, there is a world of tone-shaping that we either simply ignore or just don't want to dive into too deeply. Turning a gear discussion from bass to amp is a perfect way to bring it to an abrupt end.
Since the beginning of our instrument's history, bassists have faced the fundamental and existential problem of trying to be heard. It's solved now, but too many players don't seem to be interested in how we got here. And it's not just bassists. Even some amp manufacturers haven't been concerned with the details. A few readers might remember that in my September 2019 column, I discussed class-D amp technology. As part of my research, I called a very respected amp manufacturer to get his insight into class-D technology. His stunning response was: "We simply checked some Asian-made modules and chose the one we thought sounded best, but I don't know and never cared how they work." Even the offer of a short technical introduction was met with blissful ignorance. So, if anyone thinks they don't need to know how their amp works, at least you're in good company!
Over the course of the last 80 years or so, the fundamental technology used in our amps has been replaced—and not just once. The technological changes came in several waves and another might be on the way.
Here we are now after this last wave of amp-tech: down from 300 watts at 40 kilograms or 88 pounds in the 1970s, to 500 to 1000 watts at 1 to 3 kilograms or 2 to 7 pounds today.
For the greater part of the last century, bass amps relied on tube circuitry, and it took until the middle of the century to make decently powerful, but heavy and fragile, amps. Unfortunately, guitarists used the same technology—and sometimes even the amps that were initially made for us. (Remember that our low-end needs about 10 times the power of a guitar amp to cut through!) So, as their volume increased, our need for more power just became greater. Our problem remained until the 1960s when amps like Ampeg's B-15 Portaflex and SVT entered the scene. High-output amplification manufacturers sprouted everywhere, enabling loud rock bands to move from clubs to stadiums.
Though the transistor quietly altered the landscape of radios and small solid-state amps during the early 1950s, it took until the late '60s before this technology made it into our rigs. The first companies to make solid-state amps were those who possessed a higher engineering background. Vox, for example, released one of the first solid-state bass amps, thanks to their prior experiences with solid-state circuits from their organs. Many smaller companies soon followed, although most earned a reputation for unreliability. But the technology developed at a breathtaking pace.
This Ashdown Little Giant is more powerful than the mighty SVT at less than 1/10th the weight!
Photo courtesy of wikimedia.com
During the 1980s, clean and powerful hi-fi-esque synth sounds became trendy. This benefitted bassists with the development of clever tone-shaping options, hybrid circuits with tube preamps, bi-amping, internal DIs, and even more power.
Once we were sure to be heard, it was time to look for other advantages, like reduced weight and size, and along came another wave of new amp technology: class D. (See my column "Signal Processing in Class-D Amps," September 2019.) The basic principle behind class-D technology is pulse width modulation (PWM), which sounds as if those with higher engineering skill would once again be in the lead. Instead, there are just a few manufacturers building class-D power modules, and amp builders can use those as the foundation of their own amps. Just get one of the modules, which come in different power ratings, add a power supply and a tone-shaping circuit, and you're done. With several competing manufacturers offering identical power amps, the individual strengths have fully shifted to the qualities of their tone-shaping circuitry and other add-ons or gimmicks.
Here we are now after this last wave of amp tech: down from 300 watts at 40 kilograms or 88 pounds in the 1970s, to 500 to 1000 watts at 1 to 3 kilograms or 2 to 7 pounds today. What could be the next move? It looks as if the power-to-weight ratio has reached an end for quite some time, but tone-shaping capabilities in preamps might shift from classic circuitry to profiling or modeling amps as a fourth wave. And this time it's clearly engineering competence that will make the difference. Can you imagine what instruments we'd be playing today if our basses had made similar progress?
This killer amp and cab are a dynamic duo, but each holds its own, too.
Recorded direct into Focusrite Saffire 6 interface into MacBook Pro using Logic.
Clip 1 - Fender Elite PJ, flat EQ, no enhancement.
Clip 2 - Fender American Standard Jazz, VRC at noon, slap riff.
0:00 - no EQ
0:10 - punch engaged
0:19 - punch and bright at 2 kHz
0:28 - punch and bright at 7 kHz
Clip 3 - Fender Elite PJ
0:00 - no EQ
0:09 - drive engaged at 9 o’clock
0:20 - drive dimed
RatingsBergantino Forté HPPros:
Powerful and accurate reproduction of your instrument. Excellent tone-shaping features.
Larger than most class-D amps.
Bergantino Forté HP
Ease of Use:
Detailed and responsive, with wide tonal projection. Superior portability.
When amp guru Jim Bergantino was diagnosed with cancer, he sought solace and inspiration at the workbench, where he created the Forté HP, which combines some of the popular features of his previous amps with a robust power section. For our review, Bergantino also provided an HG410, a unique take on the classic 4x10 speaker configuration.
Drive, He Said
While the Forté HP sports all of the features of the Forté (aux in, a variable ratio compressor, 4-band EQ, and a bright switch), it includes practical options from the flagship B|Amp as well as a few additional goodies. Variable high-pass and low-pass filters provide precise tonal tailoring, whether for taming the lows in a boomy room or mellowing out the transients for a warmer vibe. Vintage tone lovers will appreciate the drive section, as it delivers harmonic enhancement in lower settings and heavy grind when cranked.
To the right of the front panel, a trio of buttons offer on-the-fly EQ bumps and other operational functions. Tapping the punch button delivers a 4.5 dB boost at 100 Hz. Holding down the aforementioned button for three seconds toggles the DI pre/post setting. Bergantino expanded the functionality of the bright switch on the HP.
While it was fixed on the Forté at 6.5 kHz, the new amp offers a choice of +6 dB at 2 kHz or +8 dB at 7 kHz. These settings can be particularly handy for finger presence and pronounced string-popping. The third button is more than a mute function. Depressing this control changes the operational impedance from 4/8 ohms to 2 ohms. This feature expands the possibilities of speaker connection, maximizing the massive 1,200-watt class-D power amp.
Another cool feature is the front-panel USB port. This is used to connect a wireless Bluetooth footswitch or install firmware updates. It also comes in handy when you need to charge your phone. Rear panel highlights include a headphone out, tuner out, effects loop, and direct out. The components are housed in a stout aluminum chassis. Large rubber feet prevent the amp from unwanted vibrations, and the HP may also be rack mounted. (Ears sold separately.)
Bergantino’s new speaker cabinet, the HG410, adjusts the arrangement of its neodymium drivers to project in a wider sound field. While three of the speakers are forward-facing, the fourth driver is a rear-firing woofer. The punchy sealed cabinet is constructed of Italian poplar with birch baffles, and tips the scales at 47 pounds.
I’ve relied on the Bergantino B|Amp and two HD112s as my rig of choice, so I was enthused to delve into the HP/HG combo. I played a Fender Elite PJ through the rig to assess its sonic possibilities. I also used the B|Amp, HD cabs, and various backline with Bergantino’s latest creations to listen for consistencies and differences. The first thing I noticed about the Forté HP was the way it presented every note with accuracy and authority—the result of an abundant, unflappable power amp. Never did the HP feel or sound like it was being overworked.
Shaping the sound of my instrument was simple, thanks to the intuitive layout. Once the gain stage and master volume were set, I could dial in the VRC compressor for a little extra tightness and punch, as well as dirty things up a bit with the drive control. Bergantino’s EQ section provided plenty of cut and boost, but it’s voiced to not significantly alter the character of the instrument. I enjoyed experimenting with the punch and bright buttons, enhancing the J pickup on the Fender Elite with extra burp and presence. I required very little from the EQ, since I used it as a subtle problem-solving tool for various live rooms.
My favorite features—essentially for fitting in the mix—were the high-pass and low-pass filters. Whether it was a boomy honky-tonk in Nashville or a 2,000-seat theater on a cruise ship, these filters kept my tone focused and present onstage. Initially I was a bit skeptical about the footswitch. I felt it wasn’t a necessity and rarely use it with my B|Amp. That said, I found the redesigned footswitch for the HP a major improvement and a useful tool in live performances. For example, I was playing an R&B medley that contained Motown bass lines and Sly and the Family Stone slap passages. With a few quick stomps of the drive, punch, and bright buttons, I could quickly transform the PJ from Jamerson mode to funk machine.
Although I was pleased how well the Forté HP performed with other speaker cabinets, it shone when combined with the HG410. The pairing was super-clean, responsive, and handled a lot of power. The narrow, rectangular design was ergonomically fantastic, as I could lift and transport the cabinet easier thanany 4x10 I have ever used. What sealed the deal for me on the HP/HG duo happened during a blues jam in a medium-sized club—an extremely loud room where the musicians prefer to crank up the volume and bash out blues/rock tunes. The rig was placed in between a Fender Super Reverb and the drum set. I never ran a line to the house PA. After dialing in the Bergantino rig for the room, I stood back to listen to how the HP/HG fit within the ridiculously loud jammers. To my surprise, the sound was thick and present, revealing the tonal tendencies of all the jamming bassists. In fact, many musicians in the audience thought they were hearing the bass through the house system. I’ve never had a lightweight rig perform so well at high volumes, and the Bergantino Forté HP/HG410 did it effortlessly.
As I was wrapping up this review, I got some good news. Jim Bergantino announced he was cancer-free. The Forté HP is his passion project as well as a monster amp, with easy-to-use features and stout tone. Discerning bassists who expect maximum performance will appreciate its thoughtful design and seemingly unlimited headroom that delivers each note accurately. Pairing it with the HG410 makes a vicious combination, rewarding users with excellent tone-shaping features and a strong footprint within any ensemble. I can say with confidence the Forté HP is one of the best amps of the year, and the HG410 is one of the best 4x10s ever designed.
A Mesa bass powerhouse that brings bells and whistles galore, but remains true to the fat tube-based tone of the WalkAbout preamp that helped inspire it.
Recorded direct into Avid Mbox into Logic X. Mesa/Boogie 1x15 cab miked with an Audio-Technica AE5400. Direct from head and mic balance split 50/50.
Clip 1: Recorded with Sadowsky Vintage PJ 5, (reverse P). Amp settings set flat except for passive mid at 10 o’clock. Power damping set to low.
Clip 2: Recorded with Music Man StingRay 5 fretless with piezo pickup. Amp settings set flat except for passive mid at 10 o’clock and 350 Hz frequency boosted to 1 o’clock. Power damping set to high.
Versatility, road-worthiness, rear-panel features, tube tone.
Might be somewhat difficult to navigate for players accustomed to simpler amps.
Mesa/Boogie Subway WD-800
Ease of Use:
Mesa/Boogie has probably made their biggest mark over the years with their guitar amps, but Mesa’s bass offerings have been providing us low-enders with a wide and respected variety of options and models since the company’s inception. The hallmark of their bass amps has been a strong midrange character that many players have grown to love. And while some other large bass-amp manufacturers tout rigs that offer transparency, much like an amplified clean DI signal, Mesa has never been shy about doing for bassists what they’ve done so successfully for guitarists: offer character, and lots of it. A few years ago, the company introduced the lightweight and surprisingly clean-sounding Subway D-800, which effectively became the beginning of a growing line of lightweight bass gear. More recently, Mesa unveiled the decked-out Subway WD-800, which boasts a 12AT7-powered preamp as one of its more significant new features. Spoiler alert: This new rig absolutely sounds just like a Mesa, and that’s a good thing.
My expectations for the WD-800 were unusually high. Why? I’ve had plenty of experience using the company’s D-800 amp since it was released, both on the road and in the studio. When I first unpacked the amp from its included carrying bag with an external pocket for cables (nice touch), the look and feel of the chassis felt very familiar. In fact, the size and weight specs of the WD-800 are just slightly larger than they are for the D-800.
The increased height of the WD-800 helps accommodate the three parametric midrange-frequency selection controls, which are located directly above the boost/cut dials for the corresponding frequencies. The tone-shaping section might appear almost dazzling to bassists accustomed to meat-and-potatoes amplifiers, because in addition to the cluster of midrange controls, there are dials for bass, passive mid, treble, high-pass filter, and power-amp damping. For players who may have thought the D-800 didn’t offer enough tone-shaping possibilities, well, here you go.
Blinded Me with Science
I’ll quickly dive into what these controls do, since some of them are not commonplace. The high-pass filter comes in handy when using high drive tones or playing at loud volumes to protect a speaker cabinet from excessive low end. The passive-mid control has a different symmetry and response than the parametric EQ section, since it controls more frequencies at once.
On the far-right side, the power-amp damping control has three different settings: low, medium, and high. A simplified explanation would be that a lower damping setting feels looser or more “bloomy” in the bottom end, while a higher damping has a tighter low end or more immediate feeling. As a very general rule, Mesa recommends trying a higher damping setting with ported cabinets and a lower damping setting for sealed cabinets. This control subtlety affects the feel of the amp more than the tone of the amp, so experimentation is key to dialing in what you prefer.
The rear panel houses all the usual suspects, and then some. It shares some key features with the D-800 and the D-800+—namely the impedance switch from 4/8 ohm to 2 ohm, DI pre/post EQ switch, tuner out, and headphone out, among others. The WD-800’s headphone out does not require that a speaker be hooked up to the amplifier, which is a feature I found very usable. Other features on the rear panel include a footswitch input for the parametric EQ (footswitch not included) and a USB charging port, which is something I’d like to see more manufacturers add to their amps.
I started out by playing fingerstyle with a passive Sadowsky PJ and the amp running through a Mesa/Boogie Subway Ultra-Lite 1x15 cab. I used the P-style pickup to determine how quickly I could dial in a classic, middle-of-the-road bass tone. With all controls set flat, the amp has a somewhat strong personality in spite of sounding clean and smooth. To my ears, this personality shows itself the most in the higher part of the low mids, where the amp is voiced slightly forward compared to its tubeless Subway line predecessors. This tone will cut through well in a full band setting without having to boost any additional mids. Turning the passive mid control brings out more of the fretboard-wood sound and fret noises, to give soft fingerstyle playing plenty of attitude, without overdriving the preamp’s 12AT7 tube at all. If I used too much of the passive mid, however, I felt like I was losing a bit of low end.
After getting a good gauge of the amp’s personality, I switched over to my fretless active Music Man StingRay 5. The natural midrange voice of the Subway WD-800 was a perfect match with this instrument. The Mesa took just enough sheen off the top end of the active bass tone and made the mwah of the bass sound as “whiny” as you would ever want a fretless bass to sound. Instead of boosting 800 Hz, which is typically an ideal fretless frequency to boost, I boosted 350 Hz and achieved the fretless tone dreams are made of.
The Mesa/Boogie Subway WD-800 is a control freak’s dream. There is more than one way to control almost every frequency the amp produces. This amp will satisfy players who want tremendous versatility out of one amp, as well as fans of the D-800 who simply want more tone-shaping power. In spite of the pleasant starting point of the WD-800, I found it took me slightly longer to get my tone than it does with the voicing control on the original Subway D-800 head. Even though the amp does a nice slap tone, I’d say it shines more with rock-oriented sounds, and it definitely comes out near the top of the heap in lightweight amplification. There are other bass-amp manufacturers who have struggled with reproducing the soul of their older amps in a lightweight class-D format. That’s not the case here. If the Mesa/Boogie Big Block or Carbine stirred your soul a few years back, this amp will make your heart beat a little faster again.