For at least a decade, the classic Ampeg SVT was the dominant bass amp for power and tone.
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?
Clip 1: Yamaha BB1600, neck pickup only, fingerstyle.
0:00 - solid-state pre
0:19 - tube pre
0:41 - both signals equal
Clip 2: Sandberg TM5, both pickups engaged, played in passive mode, slap style.
0:00 - solid-state pre
0:18 - tube pre
0:32 - both signals equal
RatingsPros:Solid construction, two preamp sections, adjustable DI level. Cons: Master volume is a little sensitive. No carrying bag included. Street: $745 Taurus Vandall-500 taurus-amp.com
| Tones:  Ease of Use:  Build/Design: Value:  |
Recorded direct using PreSonus FireStudio and PreSonus Studio One 3.
Clip 1: Passive Fender P: Low end and high mids boosted on amp. Pure switch engaged/disengaged intermittently.
Clip 2: Active Yamaha BB734A with bass and highs slightly boosted on amp.
RatingsONE800Pros:Excellent tone and excellent features in a compact housing. Cons: Oh, those lights. Street: $799 GR Bass ONE800 grbass.com | Tones: Ease of Use: Build/Design: Value: |
GR 212 Pros:Tight, efficient cabinet. Cons: It’s a little large, as is the logo. Street: $949 GR Bass GR 212 grbass.com | Tones: Versatility: Build/Design: Value: |
Shopping malls, paddleboats, pianos, and Ferrari automobiles are all Italian creations. Just try to think of our world had these inventions been limited to the confines of Italy’s borders! While the brand GR Bass is not as notable as Ferrari, musician and engineer Gianfranco Rizzi’s amps have been used by discerning players in Europe since his Italy-based company’s inception in 2015. They’re now available in the U.S., so we tested the Bass ONE800 head paired with a GR 212 cab.
Potenza dei Bassi
The ONE800 has a streamlined appearance and conservative weight at about 5 pounds, keeping it well within the backpack club of compact bass heads. The controls are plentiful and powerful, with a full compliment of EQ adjustability to really fine-tune tone.
The layout is pretty straightforward, with a few treats thrown in for good measure. All the usual refinements are in place, including dials for gain, 4-band EQ, and master out. GR has included frequency switches for mid-lows (185 Hz, 375 Hz, 800 Hz) and mid-highs (600 Hz, 1,200 Hz, 1,800 Hz). There are deep and bright switches that will boost the signal +5 dB at 50 Hz and +6 dB at 9.6k, respectively. I also appreciate the easily accessible aux-in, 1/8" headphone jack and dedicated headphone volume control, and the mute switch, for true silent practice.
Around back, the necessities are in place, with an XLR out (pre- and post-EQ selectable), effects send and return, and dual Speakon connectors. The kicker is a 9V power supply at 300 mA that can power four to five pedals. This is great for players who don’t use a ton of outboard gear, and because the ONE800 also boasts an onboard tuner, there’s room for one more stomp!
The matching GR 212 bass cabinet supplied for the review proved to be a good compliment to the ONE800. The ported cab brings 700 watts at 4 ohms, which is plenty of power with which to work. It’s not super light, at 44 pounds, but it’s not overly cumbersome, either. In addition to the pair of proprietary 12" neodymium speakers, there is a 1" tweeter with a volume control.
Bright Lights, Big Tone
I used both a Yamaha BB734A in active mode and a ’78 Fender P for this review. Starting with the BB, I set all the amp’s EQ controls flat, where the bass sounded pretty nice. I then dialed up some sweetness by bumping the lows and low mids (with the frequency set at 185 Hz), and went for the deep and bright switches simultaneously. The tones soared. I had bump, articulation, and shimmer all at the same time, and then I had a little fun.
There is one control I intentionally left out of my initial description of the front panel. Smack dab in the middle of the ONE800 is the itty-bitty “pure” switch, which is a preamp EQ bypass switch. On paper this control doesn’t sound very exciting, but with a true (aka pure) translation of our tone to A/B against, we can see how the amp is helping or hurting it. (It should be mentioned that the pure switch has an indicator light so strong it could probably help you read your charts.) While I liked my “pure” tone, it also reinforced that the amp was taking my tone to the next level—like a sweet aural exciter with a ton of volume.
The P bass loved to swim with this amp and cab combo as well. The ONE800 gave my P life and energy without coloring the tone. Again, the amp is like an aural exciter: You hear your bass, but on stun. And after running through as many genres as I could think of with the P, I felt that most any style of music would be at home with this amp/cab combo, which overall was clean sounding, tonally efficient, and had power to spare.
In all my years of writing, I never thought I’d dedicate a paragraph to the lights on an amplifier, but here we are. The row of 24 LED lights at the top of the control panel are functional and somewhat useful, but, like the aforementioned indicator light for the pure switch, they are also eye-numbingly bright. By pressing the LED button, one can engage the onboard tuner mode, scroll through four different VU meter settings, or, for more conservative players, turn the light show off. (One VU setting reminded me of KITT from Knight Rider.)
The LED switch also allows access to a fantastic noise-cancelling function. When pressed for eight seconds, the amp will switch to “studio” mode. (Repeating the process will jump back to “live” mode.) Studio mode turns off the cooling fan for quieter performance when recording, but the fan will still kick on automatically after several hours to keep the amp from overheating.
The Verdict
The ONE800 impressed. The tone is great. The EQ is great. The layout, features, and the size are all great. The tones from the amp are arguably more modern, so don’t look for tube color here, but this amp/cab combo is beastly in power and tone nonetheless. I’d happily take this rig to any gig, and the amp is compact enough to bring into a studio setting without hassle. GR Bass may not be a household name in the U.S. yet, but with offerings like this, the stateside bassists might have some new things to talk about.
Watch the Review Demo: