Troubleshooting

There are several different forms of "trouble". At least initially, let's break them down into Acoustics, Gear, Venue.

Acoustics

Feedback

Feedback happens when the sound from the loudspeaker enters the microphone or instrument with pickup only to be re-amplified. With the L1 it is typically easier to manage unwanted feedback because you typically have fewer loudspeakers, and fewer microphones to manage per System. ... full article

Hearing Yourself

Hearing Yourself can be a challenge, especially if you are not the only performer playing through the L1 you are using. But even if you have you own L1 there can be challenges on stage. If this is your issue see: Hearing Yourself

Bass Regeneration

Bass Regeneration is a special class of feedback, or regeneration, that exists in all live amplification systems. It is a very insidious and hard-to-confront phenomenon, but it is responsible for a lot of bad sound. Resonances of all kind, including those of musical instruments and those of large “boomy” rooms will also contribute to bass regeneration. ... full article

Gear

Sound Drop Outs - Intermittent

Intermittent sound can result from:

• poor connection to the B1 Bass Module. Check the wires in the Speakon connectors.
• poor connection to the R1 Remote. Reseat the connections at both ends

Sound Drop Outs - at High Volume

Classic

From Bill-at-Bose

Hilmar and I looked into sound dropouts further to find the root cause, and found the rather subtle issue that, depending on the wire gauges and how the wires were paired in the cable, loud bass signals (in the speaker pair of wires) in extra long cables could capacitively couple into the sensing pair of wires. When it happened, the L1 "thought" you were changing your B1 Bass Module configuration and would mute.

So we looked at capacitance per foot with different wire guages, and with twisted vs untwisted pairs in the same cable, and looked at our sensing algorithm, and did two things to solve the problem:

We had Mark at Audiopile.net send us some samples to our new spec, we checked them, and they worked well. This gave a method for our customers who needed a long B1 cable to get one that worked.

The second thing we did was redesign the L1 software so that it could "filter out" the effects of momentary crosstalk and not cause the problem. That way future L1's would not have the issue.

Intermittent Drop Outs Using the T1 ToneMatch Audio Engine and L1 Model II

The user manual states 5 amps or greater, so six amps is a good approximation. For that reason, we recommend only up to two L1 Model IIs on a single 15A circuit breaker in the US.

A quick review of four POSSIBLE causes of audio cutting out follows. That will help us determine what is going on.

Bass Module Cable

If there is a non-Bose B1/B2 cable, OR if the B1/B2 cable has a defective, loose connection, audio can intermittently mute. It may happen with loud music because the speaker will be vibrating and shake the loose connection. This will sound like a clean muting of all audio for a second or so. There will be no visual indication.

Fixable by tightening the screws in the connector.

For more details see: Sound Fading In and Out

Power Issues

Very low, out-of spec, AC power (less than ~105 VAC on a 120V system, or less than around ~215 V on a 230 V system. The manual states 110 and 220 for good measure) coupled with high signal level. This can be caused by a low power source, or one where the outlets are a very long distance from the electrical panel, extra equipment on the same electrical branch, power sags or dropouts, long or multiple extension cords, or small gauge extension cords.

In this case, loud music increases the current draw, and the voltage drop over the extension cord will lower the voltage enough to cause a reset of the ToneMatch Mixer, or the L1 Model II Power Stand.

If the ToneMatch Mixer resets, the LEDs (input trim level, mute LEDs) will turn off. The LCD display will remain lit, but be blank until the unit restarts. The L1 Model II Power Stand can reset but it does not show on the indicators.

In either case, the answer is to ensure the power supply is solid and dedicated to the audio equipment, and to have as short cords as possible with large wires. Also be aware that separate wall outlets may still be on the same breaker.

If there are intermittent voltage sags or outages in your area (as there are in parts of Florida, for example), it is possible that some equipment that does not use a lot of power (like mixers) will continue to operate, and equipment requiring high power, like amplifiers, may not be able to produce audio.

Those outages can happen any time, but are less likely to repeat, or unlikely to happen only at loud parts of the music.

More: Power Considerations

Overheating

If the L1 Model II Power Stand overheats, it may shut down. This can happen under direct sunlight outdoors when the temperature exceeds the maximum operating temperature. Check the access to the fan is clear (opening at the front of the power stand) and that legs are on a flat sturdy surface. If the power stand is on a carpet, it may sink down and obscure the vents on the bottom.

Defective Unit

Defective units: If the items above are not the cause, then either the ToneMatch Mixer or power stand may be defective, and you should contact customer service.

Volume Spikes

Classic

Sound Jumps - Spikes - and returns to normal volume.

R1 Remotes (Version 1)

2004-early 2005

Some users reported unexplained, momentary jumps in volume (spikes). This was tracked down the an issue with the R1 Remote.

Check the R1 Remote.

Look on the back. If there is not a designation "Model R1 '.ver 2'

you probably have an older remote.

Solution - call Support and get a new R1 Remote.

Call Support

Telephone the Bose Live Music Product & Technical Support Team (877) 335-2673 (U.S. and Canada only)* Hours of operation Monday-Friday: 9:00 AM - 9:00 PM ET

Workaround

Hilmar-at-Bose ... a temporary workaround. Simply keep the channel volume and the master volume on the remote at or above the 12 o'clock setting. The easiest way to get there is to set the volumes to about 2 o'clock and dial in the trims on the powerstand so that the playing volume is about right. That gives you some space on the remote to back it up some and also plenty of head-room when things get a little "hot" during the night. That should eliminate all problems with the spike. That also means that you can use the remote and you do not need to peg the settings at 12 o'clock. I know that this is an inconvenience and we are working full throttle to get the issue finally resolved for all affected users.

Hiss

If you have all settings on the PS1 Power Stand (Classic) / Model I set straight-up (including the R1 Remote), with nothing connected, you may hear an audible hiss within 4-8 feet.

The reason: At these settings the System is running wide-open at full power with no input signal. If you use a microphone or a recorded source playing with these settings - the System would be extremely loud. When you provide an input signal source with appropriate trim settings the hiss should be inaudible.

Solution: Use the R1 Remote to lower the Master Level when you have no input signal source.

Note: It is recommended that you use the R1 Remote.

Related Discussions

• hiss with no inputs
• white noise issues

Hum

You want to isolate the source of the hum, but this can be tricky because hum is usually the result of two or more devices interacting.

Start with the L1 fully assembled, no inputs, all settings on the R1 Remote straight up. If there is no hum then turn down the Master Level.

• Connect a sound source (simplest possible signal chain - for example microphone only).
  • Turn up the Master Level

Keep adding items to the signal chain until you hear the hum. When you get the hum, remove the source and make sure that the hum goes away. When you are sure you know what is causing the hum, check that the source of the hum is connected to the same power source as the PS1 Power Stand (Classic) / Model I

• Try a DI with a groundlift between the device that causes the hum and the PS1 Power Stand (Classic) / Model I

Cell Phone

Do not leave your cell phone on or near the PS1 Power Stand (Classic) / Model I. If there is an incoming call, the ring may be amplified through the loudspeaker.

Computer

See: Computer/Sounds if you have a computer in your signal chain.

Venue

Small Stage

When offered a chance to play, one of my first questions is about the size and position of the stage. If you find that your show is going to be compromised by a small or awkwardly positioned stage, just ask:

• For more space
• If you may set-up in a better position in the room
• For permission to remove false walls, decorative railings, hanging obstructions, and anything that can be handled with a screwdriver, or is otherwise easily restored.

In an ideal situation you will have

• A minimum of eight feet of stage depth (more if you have a large room) and
• A minimum of four-six feet of stage width for each player
• If you have four (or more) performers then you might want width as above and stage depth at least 50%-75% of the width. The farther apart the players are, the more you will want some depth behind you everyone can hear one another.

Examples (minimums - width x length):

• Two performers: 8' x 8'
• Four performers: 16' x 8'
  • Minimum: Width: 4 x 4' = 16' Depth 50% of Width = 8'
  • Better: Width: 4 x 6' = 24' Depth 50% of Width = 12'
• Six performers: 24' x 12'
  • Minimum: Width: 6 x 4' = 24' Depth 50% of Width = 12'

This makes for a tolerable stage, you will probably want a little more room, but you should be able to make this work.

Notes from Page 9 of the Bose^® Personalized Amplification System™ family of products Owner's Guide

This is the owners guide for the L1 Classic copyright © 2005

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Odd Stage Position

If placed in a corner, ask if you can be placed in the center of a wall. If the "short" wall in a rectangular room is wide enough, then that is probably your best choice for the wall behind you (if the long wall is not greater than 100 feet).