Electric Bass

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The Electric Bass and the Bose® L1 system

Configuration options and practical tradeoffs – one user’s perspective

by Andrew Douglas, Bose L1 Product Specialist

This document was not produced by Bose Corporation and is the sole opinion of its author.

Electric bassists, like electric guitarists, are perpetually in search of "great" tone. Like the electric guitar, this tone is only partly the result of the instrument itself; the choice of amplification, additional effects and speaker cabinet play a major role in coloring the overall sound. It is a symbiotic relationship.

This is not the case for most other instruments. Keyboard synthesizers, for example, rely on internal sound generators to produce their unique voice. Acoustic guitars derive their tone from design, construction and materials. For instruments such as these, the goal is not to color the basic sound of the instrument through external equipment, but rather to reproduce that sound as accurately as possible.

The Bose L1 excels at delivering transparent, clear amplification, making it well suited for acoustic instruments and voices. But these same attributes, combined with the high purchase price of the system, can be a deterrent to electric bassists looking to replace a good bass rig without losing its distinctive character.

This paper will explore, from a practical standpoint, the pros and cons of using the L1 system for electric bass amplification. It is based entirely on the personal experience of the author and reflects his views on the matter.

It costs how much?

The high cost of the L1 system is the proverbial elephant in the room. There is no avoiding the fact that an extended-bass L1 system, employing four B1 Bass Module bass modules, one L1 system, and one PackLite® power amplifier model A1 amplifier is among the most expensive bass rigs one can buy, on a par with the most exclusive of boutique amplifiers.

The immediate and obvious question is, "is it worth it?" And the obvious answer is, of course, "it depends."

The primary benefit of the L1 is its dispersion characteristic. While still a factor for the electric bass due to the overtones present in the signal, this attribute is of less importance than it is for sources that are centered in a higher frequency range. If a listener steps out of the directional "beam" of a guitar amp, the difference is instantly noticeable. With a bass amp, the difference is more subtle.

It is entirely possible to get good overall bass tone by using a conventional bass rig in a band that is otherwise exclusively built around L1 systems. The conventional rig will of course retain the limitations of all such amplifiers, in particular directionality. However, as noted above this is far less noticeable than it is for an electric guitar.

From a practical standpoint, the biggest reason to abandon a conventional bass rig is the physical size and weight of these rigs. Some cabinets can weigh 100 pounds or more and be almost the size of a refrigerator. Indeed, in 2003 as a marketing promotion Ampeg took the housing for an SVT-810 bass cabinet and actually did install a working refrigerator in it![1] With an extended-bass L1 system there are several pieces, but the heaviest one still weighs less than a typical amp head…and all are relatively compact, which makes transport easy.

But this alone in my opinion is not sufficient reason to warrant the high cost, assuming the L1 is to be used solely as a bass amp. Where it does make sense from a financial standpoint is if the system replaces both a conventional bass rig and other equipment.

A band that goes "all-Bose" can use L1 s to replace all of the back-line amps, plus the PA, plus stage monitors, plus the supporting equipment for small- to medium-sized venues. Since the Bose performance model gives each performer his or her own independent monitor "mix," the extensive additional equipment needed to provide separate monitor mixes with a conventional PA is not needed.

The total cost of a conventional system that replicates the capabilities of an all-L1 band is comparable to that of the Bose system. Therefore, if the bassist’s L1 is also used to support other sources (such as the bassist’s microphone, for example), then the purchase of the system for use as a bass amp is a logical and cost-effective move.

This raises the question of system sharing. The more sources each L1 supports, the more cost-effective it is. However, this involves some sonic, signal routing and control compromises, as will be discussed below.

Improving on the conventional bass rig

My own experience with the L1 started when I purchased two single-B1 Bass Module systems to replace my band’s overly complex PA system. At the time, the PackLite® power amplifier model A1 had not been introduced, and in any event I was not able to afford all three of the systems we now have at the time.

My band consists of a bass, one acoustic-electric guitar, a flute and a drum machine. All three band members sing. We faced the same issues that many L1 buyers must contend with, in particular deciding the most effective way to divide up two systems among three performers (and a robot).

The obvious course was to keep my bass rig (a 1200-watt component rack system driving a 2x12 cabinet, which I was very happy with) and use the two L1 s to support the three microphones, the guitar and the drum machine. This worked quite well and was a vast improvement over our previous setup.

It didn’t take long to try plugging the line out from the bass rig’s preamp into a vacant channel on one of the L1 s, just to see what would happen. The results were astonishing. The good basic tone of the 2x12 was still there, but the L1 added wonderful clarity and sparkle. It also gave the sound the superior dispersion characteristic of the L1 where it counts most, in the mid and upper frequency ranges. The fact that there was only one B1 Bass Module was not an issue: keeping the 2x12 cabinet provided plenty of support for the low end. Best of all, it allowed me to keep "my" tone, created by the preamp.

An alternative arrangement is to reverse this: Plug the bass into channel 1 or 2 of the L1 (assuming they are not occupied) and use the L1 ’s line out to feed a conventional bass rig for extra power on-stage. I did not explore this option because I wanted the tone of my preamp to come out of the L1 , and also because channels 1 and 2 on both systems were already in use.

The drawback to this hybrid solution, of course, was that I still had a fairly large, heavy bass rig to contend with. This led me to take the next step in optimizing the rig.


Optimizing the hybrid system

On the premise that part of the frequency spectrum produced by the rig’s conventional speaker cabinet was being duplicated by the L1 , I purchased a small, lightweight single-15" speaker cabinet to replace the large 2x12. The overall configuration remained the same: bass plugged into the bass rig (now a 1x15), with a line out going to the L1 . By itself this cabinet did not sound very good, but it didn’t need to…the mid- and high-end were being carried by the L1 . This effectively eliminated the major drawback of the earlier rig – a big, heavy cabinet. I did prefer the tone of the 2x12/L1 hybrid system, but I was willing to compromise to gain compactness and light weight.

This final iteration of the hybrid system displayed many of the physical/logistical benefits of the L1 , specifically size and weight. The 1x15 cabinet I had selected weighed less than 30 pounds and was about as small as a 1x15 cabinet can get. My four-space amp rack also made use of a very lightweight power amp.

Moving to the L1

When the PackLite® power amplifier model A1 was introduced, I decided to give it a try. Curious about how it would sound compared to my satisfactory hybrid setup, I purchased the

PackLite® power amplifier model A1 Extended Bass Package (PackLite® power amplifier model A1 and two B1 Bass Modules). After a month of A/B comparisons, I decided to keep it. The tone was good, the logistics were good, and there was a side benefit: the drum machines were now able to take advantage of the additional power and bass support provided by the PackLite® power amplifier model A1 and extra B1 Bass Modules.

Soon after, I was in a position to buy a third L1 , which I did…basically because Bose had been right about every other claim, so I was willing to purchase it on faith by that time; they said that one system per performer is the way to go, and I had to find out. Needless to say I wound up keeping it.

So I had ultimately worked my way into owning a $3300 bass amp. Was I insane? Perhaps, but there were good reasons to add the third system. These had at least as much to do with the improved overall sound of the band as it did with the bass tone that the extended-bass L1 gave me. Giving each singer a separate L1 made a significant difference in the monitoring situation – one that surprised us. We would never have guessed how much better having one system per performer sounded had we not tried it for ourselves.

Another notable difference came from the fact that I was no longer sharing a system with the guitar. Having two discrete sources resulted in better overall sound, even though the two instruments were not "stepping on" one another in terms of frequency distribution. This is no doubt due to the ambience created by the physical separation of the L1 s.

In terms of tone, the sound was different from the hybrid solution. The bottom end was tighter and punchier. It didn’t have the raw physical "thump" of a big speaker being driven by a large amplifier, but I soon realized (based on stepping away from the system and listening to it from the audience) that particular characteristic is not actually all that important.

The improvement in sound was incrementally better, but the difference was not as dramatic as it had been when moving from the conventional setup to the L1 . Nevertheless, the consensus was that it was sufficiently better overall to justify the purchase. Accordingly, I sold my conventional rig (which offset the cost of the PackLite® power amplifier model A1 and extra B1 Bass Modules) and now use the extended-bass L1 system, driven by a Line6 BassPODxt, as my bass amp. My L1 also supports one channel of the drum machine and my vocal.

Tone options

Many bassists have found results they like using only the L1 system (typically a 2 B1 Bass Module system) using the existing presets. To my ear, however, the system alone can sound a bit dry and lacking color, even with the full extended-bass package.


The alternative is to feed the L1 with a signal that has been put through a preamp of some sort. This can be accomplished in any one of several ways:

  • A rack-mount preamp
  • A pedal such as the SansAmp Bass Driver DI
  • A modeler such as the Line6 BassPODxt

I’ve had excellent results using the Line6 BassPODxt. By using the BassPODxt’s amp and speaker cabinet models, combined with the Studio Direct output mode, I’ve been able to get a tone that I find very pleasing…quite close to my old bass rig. It also offers some added flexibility to cure problematic EQ situations; for example, I’ve found that the simple expedient of changing the cabinet model for different venues (indoors vs. outdoors, for example) can improve the sound dramatically in a single step.

The Line6 equipment is well thought out, but it should be noted that the best results can only be obtained if the user takes the time and effort to learn how the system works. Many musicians lack the time or patience to dive deeply into devices such as these and seek a simple "plug and play" answer.

There’s also the issue of "true" tube tone. Digital modeling can do many wonderful things, but it is not able to provide genuine tube tone. Fortunately, for bassists this is not nearly as critical as it is for electric guitarists, and the Line6 gear is able to produce excellent tone in its own right.

Thump

The first question many bassists have about the L1 is, "can it push enough air?" This is an area where I believe many misconceptions come into play. Bassists tend to focus on how well a rig can reproduce the lowest frequencies, and how well it can produce the physical sensation of being hit with a powerful, low-frequency sound wave. My observation has been that the important part of the spectrum for electric bass isn’t down low…it’s in the lower end of the midrange, from about 100 Hz up. Adding too much signal below that point actually serves only to muddy the sound in my experience.

Also, the bassist’s perception is different from that of the audience. The bassist feels the low "thump" more because he/she is standing right in front of the cabinet, or at least in close proximity. Out in the audience, that physical "hit" of air movement, while it may still be present, is lessened.

The real question is, what sounds best? Does having a powerful "thump" really serve the music? The important thing is to listen to the sound and abandon preconceived notions about what "should" sound right. Like many bassists, I used to cut the mids and boost both bass and treble because this "smiley face" EQ curve sounds good soloed. But in the mix, the bass disappears if it’s EQed this way. Now I leave the bass EQ flat and boost the mids…and the overall sound of the band is excellent, with the bass sitting prominently in the mix and no blurriness or muddiness. This EQ curve doesn’t sound quite as pleasing when the bass is being played by itself, however.

Ultimately this is a matter of personal taste. Several L1 users are using large powered subwoofers as the Mackie 1801 subwoofers to generate that extra air movement. In my experience going that far is not necessary.

Two or four B1 Bass Modules?

Another misconception is that adding more B1 Bass Modules will add "more bass." This is not so. What it does do is add more headroom. Bass frequencies require a lot of power, and the more you can throw at them, the better they’ll sound…at any volume. This is also true of conventional rigs: My old rig had a 1200 watt amplifier driving a 2x12 cabinet and it sounded superb because I was never pushing the amp hard. Unlike electric guitars where a heavily-driven tube power amp can produce improved tone, with electric bass it’s far better to have plenty of clean power on tap.

Similarly, adding a second speaker cabinet to a conventional rig can improve the tone even without an increase in amp power. The basic concept is the same; with more speakers available, it’s not necessary to drive them as hard.

Note that the full extended-bass L1 system delivers 1000 watts and has a total speaker area roughly the same as a 4x10 cabinet. This is, of course, highly misleading, but it does show that the system is in the ballpark of a good conventional rig.

The audible difference between a two-B1 Bass Module system and a four-B1 Bass Module system with an PackLite® power amplifier model A1 is not that one "goes deeper" or has "more bass" than the other. The PackLite® power amplifier model A1-equipped system definitely does have more "presence" and "punch" than the two-B1 Bass Module system. This is readily apparent in live listening demonstrations.

Summary

My own journey from conventional amplification to an all-Bose system has covered most of the possible configurations, from conventional rig to hybrid to a full-bore extended-bass L1 system. At every stage I’ve been rigorous with my decision to move to the next step, conducting extensive A/B comparisons and choosing the most viable overall option. It says a great deal about the engineering of the L1 that I no longer own a conventional amplifier.

Overall, my experience with the hybrid conventional rig/L1 arrangement was very positive. For the bassist who simply cannot afford his or her own L1 system, but who has access to one belonging to a bandmate, I believe that a hybrid arrangement is an effective, but not optimal, solution. It is, in my opinion, well worth taking advantage of the 45-day trial period to test the extended-bass L1 system against such a hybrid system. It was only after I had done this that I concluded that the added benefits justified the cost.

To recap the main points:

  • Purchasing an L1 system (particularly an extended-bass system) solely to replace a conventional bass rig is not financially justifiable in my opinion. The incremental benefit provided by the L1 does not warrant the added cost. However, if it’s used to replace additional equipment as well, it is very cost-competitive.
  • If band resources limit the number of L1 s available, continuing to use a conventional bass amp can give excellent results, especially if combined with an L1 to create a hybrid system.
  • A full extended-bass L1 system can and does make a viable replacement for a conventional bass rig and offers the following benefits:
  • Multiple use as a vocal monitor/PA replacement
  • Reduced weight and bulk
  • Improved sonic characteristics
  • L1 tone that is directly comparable to a high-quality conventional rig can be realized through the use of preamps or amp modelers.
  • The "lack of thump" concern is in my opinion a red herring. The L1 produces a full, rich, musical, pleasing bass tone without having to push a huge amount of air.
  • The extra presence and punch provided by additional B1 Bass Modules and the {{A1]] is well worth the cost in this application.

About the author

Andrew Douglas is a professional writer and an amateur bassist ("I’m good enough to get asked back, and nobody’s thrown a rotten tomato at me yet…but there’s always a first time.") who lives in Bridgeport, Connecticut. He has been playing off-and-on with the same two close friends for over 20 years, and the three of them have been performing as a band for over 10 years. He is also a Bose L1 Product Specialist.

About the equipment

Original rig:

  • Pre-Fender SWR Grand Prix tube preamp
  • PreSonus Blue Max Compressor
  • Stewart World 1.2 1200-watt power amp
  • Avatar 2x12 w/horn, later replaced by a Flite Sound 1x15, no horn

Current Bose rig:

  • Full extended-bass Bose L1 system (L1, PackLite® power amplifier model A1, four B1 Bass Modules)
  • Line6 BassPODxt w/Shortboard, running into Ch.2, preset 00
  • Studio Tone amp model (SWR)
  • Studio Tone 4x10, Silvercone 4x10 or Green 25 4x12 cabinet models, depending on venue
  • Tube mic, close, 20-30% room setting

Basses:

  • Original bass in use at time of L1 purchase, Carvin LB75A modified with Bartolini pickups and an Aguilar preamp
  • Current bass, MusicMan Bongo 5 HH w/piezo