L1® System FAQ

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This is the latest version of the L1® FAQs originally published in February 2008 on the Main Bose Site.

Bose Official Frequently Asked Questions

Official Manuals, Guides, FAQs

L1® Systems and the Bose® approach to live sound

How does the Bose® approach to live sound work?

The L1 system represents an entirely new approach to live amplification. In this approach, the mixer, PA speakers, monitors and backline amplifiers are replaced by special Cylindrical Radiator® loudspeakers located behind the musicians. These speakers have the unique ability to disperse sound evenly across the stage and into the audience with very little change in sound level.

The Bose approach mimics the wide sound stage of many acoustic performances: Each player has control over his or her individual sound, and a group's sound comes from multiple directions corresponding to the musicians' positions on stage. This property of acoustic music enhances our ability to hear and appreciate individual instruments and voices in ensemble passages.

Is this technology better suited for seasoned musicians who already have tons of gear, or for musicians who are just getting started and need a simple solution?

L1 systems are equally valuable for seasoned musicians and beginners. Experienced performers immediately recognize they can hear better and therefore play better, and they instantly appreciate the easy setup. Inexperienced musicians can spend more time playing and less time hassling with equipment. L1 systems can help them develop into better players precisely because they can hear themselves and each other better. Musicians at all skill levels benefit from knowing the sound they produce on stage is the same sound that's projected to the audience.

Are there similarities between an L1 system and line arrays currently in use?

Line arrays have been used for large concert performances as the PA component of a traditional amplification system. Unlike these large-venue systems, an L1 system is designed as a portable implementation of a line source, positioned behind a musician?providing accurate coverage for the performer, other musicians onstage and audiences.

In nightclubs you normally see very large loudspeakers for bass. How do your smaller bass enclosures compare? What makes them so special?

Because our bass modules are used in an integrated L1 system (with amplification and signal processing), performance can be enhanced in ways conventional component-based solutions can't. At the same time, the B1 bass module is modular, making it easier to produce higher bass output for instruments and styles that require it. An upright bass in a jazz trio might need only one bass module, but the electric bass in a 10-piece funk band might use four.

Are sound operators required with L1 systems?

No. When musicians are in control of their own amplification with L1 systems?and they know the same sound they're creating onstage is projected evenly to the audience?they're well equipped to create the desired balance of voices and instruments themselves. Without assistance from sound operators.

What happens if a musician is blocking the view of an L1 system? Doesn't that block the sound?

Sound can diffract (bend) around objects. As long as a musician isn't standing directly against the L1 loudspeaker, the sound diffracts around the musician and other objects like a keyboard or instrument.

How loud can an L1 system play?

The new approach can compete with the maximum levels created by most conventional amplification systems. What's changed is that musicians in a band will rarely, if ever, struggle to hear themselves and each other, eliminating a major reason for excessive volume levels. With the new approach, dynamics are vastly improved, contributing greatly to musical quality. In testing at Bose, musical groups plagued by the problem of excessive loudness were delighted to find that, in one or two sessions, their average volume level had dropped drastically while their peak level remained the same. They expressed an enormous increase in the enjoyment of playing, and audiences expressed appreciation for music that was exciting but not overwhelmingly loud.

Is this really a "plug and play" solution? How long does it take to set up?

L1 systems disassemble into easy-to-carry pieces. Everything can be carried by hand with no need for special equipment. The systems are also designed for easy assembly in just a few minutes. No group mixing is required with L1 systems, eliminating the task of wiring instruments to a mixer, then from mixer to amplifiers and speakers. Musicians simply set up their L1 systems, plug in and they're ready to play.

Does every musician in the band need his or her own L1 system?

No. In some situations?a larger ensemble on a small stage, for example?testing showed that two or more musicians standing or sitting next to each other could share one L1 system without a significant erosion of the benefits of the approach.

Can one musician use an L1 system while the rest of the band plays through a conventional system?

Yes?there are two ways. A performer can use an L1 system onstage without connecting to any other house reinforcement equipment, including stage monitors and main front speakers (or "house mains"). This allows the musician using the L1 system to hear himself better and to be heard better by the other musicians onstage as well as the audience.

A performer can also use an L1 system onstage while sending his or her audio signal(s) to a house PA. In this case, the musician and the band enjoy the benefits from the L1 system's sound onstage only. There are no advantages for the audience. The potential for excessive reverberation and the problems of bulky and complex equipment continue to exist when the rest of the band plays through a conventional setup.

Can acoustic instruments be amplified with an L1 system?

Yes. If the acoustic instrument has a pickup system, you can connect to an L1 system's power stand or into a ToneMatch® audio engine. When pickups aren't present, a microphone may be used. An L1 Model I power stand is equipped with 24V phantom power capability for channels 1 and 2 to power condenser microphones. With a Model II system, use a direct box or transformer to adapt the mic cable to the power stand's 1/4" analog input connector.

How does this approach work for electric guitar?

There are three main ways an electric guitar's tone can be included in the L1 system approach.

    With a modeling amp. An electric guitarist simply plugs into a modeling amp, then plugs the output of that amp into an L1 system. This is the most convenient and elegant way to use electric guitar with an L1 system.

    With a preamplifier. Most tube-based or solid-state guitar preamplifiers can be used with an L1 system. Just plug the output of the preamp directly into the L1 power stand or ToneMatch audio engine.

    With a traditional guitar amplifier. Place a microphone in front of a traditional tube amplifier and connect the mic cable to an input on the L1. Exceptional results have been obtained with the use of low-wattage tube amplifiers— increasingly popular with players who want the tone of a tube amp without producing extremely high sound levels onstage.

The advantage gained in these methods constitutes what is arguably the most important advance in electrical guitar sound since the invention of the guitar amplifier itself: The L1® Cylindrical Radiator® loudspeaker overcomes the problem of uneven sound dispersion experienced with traditional guitar amps. The dispersion pattern of a typical guitar amp can be so harshly directional that the sound may be painful to listeners right in front of the amp speaker, but dull and muddy to others off to the sides. With an L1 system, the sound a guitarist hears onstage is dispersed evenly and clearly throughout the audience.

How does the output of an L1 system compare to a loud stack of guitar amplifiers and cabinets?

The output of an L1 system can compete effectively with the output of a full stack of guitar amps and cabinets. There are additional benefits that distinguish an L1 system from a full stack's acute directional beam, including the wide, even sound coverage of the Cylindrical Radiator® speaker. An L1 system can also be used to amplify other instruments and voices at the same time

Can you create distortion for guitars with an L1 system?

No, but you can amplify distorted sounds through an L1 system. Distortion must be produced first, then fed into an L1 power stand as a non-clipping signal. Key ways to do this:

    Use inline devices. Overdrive/distortion effects pedals and DSP-based amplifier modelers can be used effectively with L1 systems.

    Mic a guitar amplifier. Mic the speaker as closely as possible. The trick here is to run the amplifier at the lowest possible level to attain the desired tone without diminishing L1 system benefits. Small, low-watt amplifiers can be used onstage; louder amplifiers can be located offstage.

    Use a loading device. Some electric guitarists may prefer to use their amplifier's output as an input signal into the power stand. Before doing this, you must use a load device such as a "plate soak" or a "hot plate" to produce a line-level output suitable for the input stage of the power stand.

    Use the line output of a guitar amplifier. This option may be suitable for some guitarists. Turn the amplifier volume down so only the L1 system is heard.

Where can an L1 system be used?

An L1 system is suitable for amplified music performances in venues with occupancies up to 500 people. Typically this translates to maximum listener distances of about 150 feet (45 meters). The system will fill venues where the vast majority of live music performances take place, including small auditoriums, places of worship, gymnasiums, ballrooms, clubs and coffeehouses. Tests show that in larger venues, a musical group can use the L1 systems onstage and enjoy the benefits of hearing themselves and each other better. Signals from the stage can then be fed to speakers that supply sound to distant seating areas.

Can I use the system outside?

Yes. The system has been tested to operate in 32°F to 122°F (0°C to 50°C) temperatures; it can also be stored in -22°F to 158°F (-30°C to 70°C) temperatures. Take precautions in light rain to cover the back panel of the power stand. Keep water out of the air inlet slits inside the back panel, on the loudspeaker drivers or inside the L1 cavity on the power stand.

Can DJs benefit from this system?

Yes, this system offers important advantages over conventional systems for DJs. One problem with portable PA systems is their stand-mounted speakers are very loud close to the speaker, and not loud enough away from it. With the L1® Cylindrical Radiator® loudspeaker, you can adjust for the desired volume level on the dance floor and in the audience, and then walk right up next to the speaker without it getting excessively loud—translating into much greater comfort for listeners. The system also has a sleek, elegant profile that fits nicely into event décors and minimizes sightline issues. And it's easier to transport, set up and break down than most portable PA systems.

Can L1 systems be used as a traditional PA?

Yes. L1 systems can be used to replace PA speakers. Their unique radiation properties help them deliver more even sound coverage and a larger stereo field?benefits confirmed in listening tests. Compact size is also an advantage for transport and rapid setup/breakdown.

Are L1 systems prone to feedback?

L1 systems are resistant to feedback, but not immune from it. Putting a live mic right up against the loudspeaker, for example, will create feedback. But in the vast majority of cases, L1 performance in this critical area has proven to be significantly better than the traditional use of separate backline amplifiers, monitors and PA systems.

Can I use two-wire Speakon® cables for the B1 bass modules?

No. Only four-wire Speakon cables should be used with the power stand. The additional two wires (+2 and -2) in the connector are used for sensing purposes. With the four-wire cable, the power stand can sense and adjust (EQ and level) for 0, 1 or 2 connected bass modules.

How can I tell if I'm using the correct four-wire Speakon cable for bass module connections?

When you plug a four-wire Speakon cable into an L1 system while music is playing, you will clearly hear the loudspeaker mute for a moment. If you're using an incorrect cable, the momentary muting won't occur.

Can I connect a passive subwoofer to the bass module output?

No. We don't recommend connecting anything to this output except a B1 bass module, as the internal amplifier and bass module(s) are designed to properly equalize the system when connected. You may use the bass line-out connection, however, to feed a powered subwoofer or additional amplifier.

Can I use the bass line out to connect to a bass amplifier and cabinet?

Yes. The bass line-out connector provides a flat 40 Hz to 180 Hz bandpass signal when no B1 bass modules are connected. We recommend unplugging the bass modules to ensure correct EQ compensation of the bass line-out jack and phase consistency.

Why does the sound coming from an L1 system change when I plug a 1/4" cable into the bass line-out connector?

L1 systems produce audio in the range of 110 Hz to 18,000 Hz when the bass line-out jack is not in use. The frequency cutoff point moves from 110 Hz to 180 Hz when you plug a cable into the bass line-out jack, accounting for the tonal change you're hearing.

See also: Bass Line Out / FAQ Extension

What about using just the lower half of an L1 system's loudspeaker in places where the ceiling isn't tall enough for full assembly?

You can do it, but using only half of an L1 loudspeaker will significantly impact system performance. The EQ will be incorrect, and sound coverage decreased. Plus, in order to hear yourself properly, it's best to have your ears at the same height as some part of the loudspeaker—which may be difficult unless you're seated.

See also: Half Stack

There's a buzz in the system. Any suggestions on how to fix it?

Most times, noise you hear through an L1 system is caused by outboard gear and power sources, not the system itself. One of the most effective ways to alleviate buzz and hum in any system is to plug all interconnected gear into the same electrical circuit. Guitar players or vocalists with effects should plug them into the same electrical outlet as the power stand. This normally fixes all problems. A power strip may be helpful, but avoid using three-prong to two-prong adapters, also known as "cheaters" or "ground lifters." Bypassing a safety grounding mechanism is a serious safety threat.

Noise and buzzing are common problems with pro audio gear. But the new Bose approach to live sound can dramatically reduce gear noise because it uses a simple, independent system. The typical buzzes and hums associated with ground loops are eliminated when you use an independent system that's not electronically connected to other equipment.

Why doesn't Bose publish full system specifications for L1 systems?

While some specifications add value when comparing two otherwise similar products, they're mostly meaningless for a product as fundamentally different as the Cylindrical Radiator® loudspeaker and the L1 system. In addition, most specifications used to describe sound systems can be very misleading. They suggest relatively complex physical or perceptual properties can be condensed to a single or small set of numbers that defines overall quality or performance. In many cases these numbers only loosely relate to what you would experience in a real-world application.

There are also several variations in how a specific measurement can be carried out, making number comparisons useless. We believe it serves our customers better to describe L1 systems in terms they can relate to more directly. We also encourage customers to experience an L1 system personally, either at a demonstration or in actual real-world trials they conduct themselves.

L1 Model I Systems

What exactly are ToneMatch® presets and what are the benefits of using them?

Skilled studio engineers listened to the sound of specific instruments and microphones being played through an L1® system, made adjustments to improve the sound quality and then saved those settings as ToneMatch presets. Now the high level of tone customization most musicians experience only in recording studios is instantly available at your live performances. Sound check can be as simple as plugging in your instrument or mic and selecting the appropriate ToneMatch preset.

What is the proper method for setting gain on an L1 Model I power stand?

There are three gain settings for the primary channels (1 and 2) and two gain settings for the secondary channels (3 and 4). To set the gain for the primary channels 1 and 2:

  • Adjust the input gain
    Set the trim for the individual channel at the back panel of the power stand. Supply a maximum source signal and watch the LED. When you start to see it flash red, back off slowly on the trim knob until it flashes green again.

  • Adjust the channel gain with the R1 remote control
    With the master at zero, set the respective channel gain to 6. At this point, the LED on the remote will be at the same intensity as the LED on the back panel of the power stand. This is considered optimum gain. You then can add a bit more channel gain on the remote if it's required.

  • Set the remote master gain
    The remote master knob is the last stage of gain. This knob gives you control over all four channels of the power stand.

To set the gain for channels 3 and 4 simply adjust the input gain of the individual channel. These channels don't have indicator LEDs, but are designed for 0 dB line-level signals (e.g., from an effects device, mixer or MP3 player). Use the remote control master knob as the last stage of gain for these channels.

What is the recommended way to set the gain for a Model I system when using it with a T1 ToneMatch audio engine?

  • Make sure the power switch on the power stand is in the Off position and the remote control is disconnected

Note: The remote should be disconnected so that the ToneMatch audio engine solely controls the volume of the L1® system.

  • Make sure the ToneMatch audio engine power switch is in the Off position and its power supply is connected
  • Set the ToneMatch audio engine master volume control to 0
  • Plug one end of a 1/4" phone plug cable (not supplied) into the master output port on the ToneMatch audio engine. Plug the other end of the cable into the line-in jack of channel 3 or 4 on the L1® power stand

Note: We recommend only connecting to the line inputs of channels 3 and 4 because channel 1 and 2 mic/line inputs have volume controls, equalization and presets that could affect the ToneMatch audio engine's sound and performance.

  • Set the line-in level control on the power stand to approximately 2
    Note: In some circumstances, it may be necessary to slightly adjust the level of this initial setting to attain the desired gain structure. Note: Bose has revised this, and now recommends setting the level control to approximately 3.

See also: L1® Model I / FAQ Extension

  • Turn on the ToneMatch audio engine
  • Turn on the L1® power stand

Do the mic inputs have phantom power?

Yes. The primary input channels 1 and 2 have a button selector for +24V phantom power for microphones that require it.

I thought phantom power was 48 volts. Why does the power stand only supply 24 volts?

Phantom power is a DC voltage that powers the preamplifier of a condenser microphone. It can be in a range of 11 – 48 volts.

What input connections will channels 1 and 2 accept?

Channels 1 and 2 accept two types of input connections: a balanced XLR (mic) connection and a 1/4" phone connector unbalanced (line) input for instruments

Why don't channels 3 and 4 have presets, XLR inputs and line outs like channels 1 and 2?

The L1® Model I system was designed with the individual musician in mind. Primary inputs 1 and 2 are intended to receive signals from an instrument and a vocal mic. Each musician's instrument and voice can be heard through his or her own L1® system. The remaining channels are suitable for additional direct instruments, mixers and MP3 or CD players.

What are the critical frequencies (Q-points) of the remote control?

The mid control is centered about 1.2 KHz with a Q of approximately 1. High and low responses are shelving. We don't quote shelving frequencies because there's no clear industry standard definition of a shelf's "cutoff frequency."

Will an L1® Model I system still work without the remote control?

Yes, but it's not recommended. If you turn on the power stand without the remote connected, it will operate as if the remote were connected with all control knobs at the center position. Alternately, if you turn on the power stand with the remote connected and you then disconnect the remote, the power stand will retain the last settings of the remote before you disconnected it.

Is the remote control cable an off-the-shelf MIDI cable? Are there extensions available?

The remote uses a special 7-pin DIN cable commonly referred to as a "7-pin phantom MIDI cable." This cable configuration is sometimes used to connect rack-mount guitar effects to their pedals. A standard 5-pin MIDI won't work. Bose sells a 7-pin DIN (20') replacement cable.

Does the remote use MIDI-compatible commands? Can I automate remote functions using MIDI communications protocol? Can I customize my settings using the remote port on the power stand?

The remote control and associated hardware are proprietary and don't use MIDI communications protocol. The remote control port on the power stand won't function with standard MIDI products.

Does an L1® Model I system have built-in effects?

No. There are connectors, however, for inserting effects units into channels 1 or 2 of the power stand. These connectors require standard insert cables with 1/4" TRS connections on one end and dual male 1/4" TS connectors on the other. You may also purchase a Bose ToneMatch audio engine, which includes a complete suite of studio-class effects and processing.

Can I use effects equipment with the L1® Model I power stand?

Channels 1 and 2 allow for a TRS line input/output connection for external effects units. Inserting the plug halfway connects to "Send;" inserting fully connects to "Return." Some musicians may prefer to keep a "dry" sound intact without the full effects loop; inserting the plug halfway into the connector will maintain the original signal and not route the channel solely through the effects module. You can use either a serial or parallel connection for effects units, as detailed in the owner's guide. In addition, you may also use a Bose T1 ToneMatch audio engine with an L1® system. It features a complete suite of studio-class effects and processing.

How can I add more inputs to my system?

Use our multichannel T1 ToneMatch Audio Engine, specifically designed for L1® systems. It offers three mic/line inputs, two line inputs (L/R), our largest library of ToneMatch presets, proprietary zEQ and a complete suite of studio-class effects and processing. Simply connect the ToneMatch audio engine via an analog 1/4" TS cable from its master output to channel 3 or 4 of the L1® Model I power stand.

What's the "data out" connector for?

This is a SPDIF connection for digital recording of channels 1 and 2. It runs at a sample rate of 48 kHz. Channels 3 and 4 aren't included in this output.

L1 Model II Systems

Why does an L1 Model II power stand contain only a single analog input?

The L1 Model II system provides a single analog input suitable for many applications and compatible with standard mixers, DJ mixers, laptops and other devices. This enables the layout of the power stand to be less cluttered, with no unnecessary connectors. The end result is a clean, compact and efficient design.

For musicians who need more inputs, our multichannel T1 ToneMatch® audio engine is designed to work with an L1 Model II system via a simple digital connection. It offers three mic/line inputs, two line inputs (L/R), our largest library of ToneMatch presets, proprietary zEQ and a complete suite of studio-class effects and processing.

What's the proper method for setting the gain on a Model II power stand when connected to an analog source?

While playing your instrument or audio source as loudly as you would in performance, adjust the trim level on the power stand until you see the LED go from yellow to red. Then back the trim level off until the signal LED is predominantly yellow with brief peaks into red.

What's the proper method for setting the gain on a Model II power stand when connected to a T1 ToneMatch audio engine?

Set the output volume of your source to normal operating volume. Make sure the master volume and channel volume on the ToneMatch audio engine are set to 0. While playing your instrument or audio source as loudly as you would in performance, turn the appropriate channel's trim control clockwise until the signal/clip indicator glows green or yellow. If the indicator flashes red or glows steady red, turn the trim control counterclockwise to decrease the level.

T1 ToneMatch Audio Engine

T1 ToneMatch® Audio Engine

I already own an L1 Model I (or Model II) system. Can I purchase the T1 ToneMatch audio engine separately and use it with the system?

Yes. The ToneMatch audio engine can be purchased separately for use with both L1 Model I and Model II systems. The ToneMatch audio engine connects to Model II systems with a single digital cable via the ToneMatch ports.

When connected to a Model I system, the ToneMatch audio engine requires a separate power supply?available through Bose or authorized dealers of the L1 family of products. Use an analog 1/4" TS cable to connect the ToneMatch audio engine's master output jack to the input of channel 3 or 4 on the Model I power stand.

What are the benefits of the ToneMatch port?

It provides for a single digital connection from the T1 ToneMatch audio engine to an L1 Model II power stand. It also delivers power from a Model II power stand to the audio engine. You enjoy digital quality audio?with no need for an additional power supply and excessive wiring.

How can I verify the version of ToneMatch presets I have?

Access the global preferences menu to confirm which interchangeable ToneMatch preset banks are loaded in your T1 ToneMatch audio engine. Use the rotary encoder to select the global preferences mode. Press the Menu button to select the menu list. Then rotate the Select button to scroll through the list and highlight the ToneMatch presets description.

What is the concept behind zEQ, and what are the benefits?

Ordinary tone controls are generic by design: High, Mid and Low controls are spread out across the entire musical spectrum. Proprietary zEQ automatically shifts the range of these controls so they correspond directly to the range of your voice or instrument. In brief, zEQ allows more precise control over your tone, making it easier to fine-tune your sound.

Do the mic inputs of the ToneMatch audio engine have phantom power?

Yes. +48V phantom power can be applied to channels 1 – 3.

Can I assign multiple effects to any or all channels?

Yes. You can run multiple effects on one channel while simultaneously applying different effects to each of the other channels. Each effect type has designated user-adjustable parameters; these individual parameters may also differ from channel to channel.

Can I create a submix to send to a house PA system or recording device?

Yes. Use Aux mode on the T1 ToneMatch audio engine to send selected input channels to the Aux output. You can also choose the type of submix signal you want to send: Dry (after preamp), Pre (includes equalization and effects) or Post (after fader).

What is a Bose scene?

It's a specific T1 ToneMatch audio engine processing setup that's a default starting point for achieving great sound quickly in a variety of applications. Five Bose scenes are built into the ToneMatch audio engine: Factory settings, Singer/songwriter, DJ/playback, Drums and bass, and Electric works.

What is a user-defined scene?

A user-defined scene is a "snapshot" of the complete state of the T1 ToneMatch audio engine settings at any given moment. You can store, recall and edit up to five different user-defined scenes. After editing a Bose scene to your preference, simply save it as a user-defined scene for quick recall at a later time. These customized scenes will help you achieve consistent sound with minimal configuration time.

What is a shared scene?

A shared scene is a user-defined scene you can send out of the T1 ToneMatch audio engine to a PC running L1 updater software. Once you've transferred a copy of the scene file to a PC, you can easily share it with other ToneMatch audio engine owners.

Can a T1 ToneMatch audio engine be used as a stand-alone mixer?

Yes, but many key advantages of an L1 system?like even sound coverage, consistent tone, and portability?aren't realized when a ToneMatch audio engine is used with conventional speaker systems.