Troubleshooting

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There are several different forms of "trouble". At least initially, let's break them down into Acoustics, Gear, Venue, Power.
In general, troubleshooting is the identification of, or diagnosis of "trouble" in a system caused by a system failure of some sort. The problem is initially described as symptoms of malfunction, and troubleshooting is the process of determining the causes of these symptoms.

— Source: Troubleshooting - Wikipedia

Bose Official Frequently Asked Questions

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

No Sound

  • Check the power (System on, power indicator green)


Low Sound

You can hear the sound but it is not loud enough.


Bass sounds fuzzy

Warning - Use Blue B1 Cables NL4 cables with your L1® Classic / L1® Model I / L1 Model II

Classic This information is applicable to the L1® Classic
L1 Model I This information is applicable to the L1 Model I
L1 Model II This information is applicable to the L1®  Model II

If you are using a B1 Bass Module with your Power Stand it is ESSENTIAL for proper operation that you use the BLUE B1 cables supplied with the B1 Bass Module. This is required so that the L1® Classic or L1® Model I or L1 Model II Power Stand can correctly identify when there are B1 Bass Modules connected to it and if so, how many.

B1 Cable


Please click the picture above for ordering information.

See: PS1 Power Stand / Bass Line Out for details about how the Power Stand adapts to the number of B1 Bass Modules that are connected to it.

You may also use high quality NL4 cables (four conductor cables). Alternate and longer cables for B1s



Does not Respond to R1 Remote

Classic This information is applicable to the L1® Classic
L1 Model I This information is applicable to the L1 Model I

  • Check connections (See PS1 Powerstand Connections/Interactive for close up view of input panel).
    • Power Stand
    • Remote — try both top and bottom
    • Make sure input sources are NOT plugged into Channel 1 or Channel 2 Insert points

Sound Drop Outs - Intermittent

Intermittent sound can result from:


  • On the L1® Classic or L1® Model I check that the Presets buttons are completely on a Preset. If you have recently changed Presets, go up an then back down again to make sure you are completely dialed in. See: Preset 56.5 hint from DJ Argyx.

Sound Drop Outs - at High Volume

Classic This information is applicable to the L1® Classic

From Bill-at-Bose[1]

Hilmar[2] 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.

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[3], or the L1 Model II Power Stand.

If the ToneMatch Mixer[3] 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[3] or power stand may be defective, and you should contact customer service.




Volume Spikes

Classic This information is applicable to the L1® 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[4] ... 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

Popping Sounds on Shutdown

There are a couple of things you can do.

  • Remove the Cylindrical Radiator® and B1 Bass Modules before turning off the Power Stand. You will not harm the Power Stand, and it will be easier to access the cables.
  • If you are using a L1® Model I or L1® Classic, on the R1 Remote, turn down the Master Level.

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

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


DistancesP9Manual.png

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).

Power Considerations

L1 Model II This information is applicable to the L1®  Model II
L1 Model 1S This information is applicable to the L1®  Model 1S
L1 Model I This information is applicable to the L1 Model I
Classic This information is applicable to the L1® Classic



This information pertains to AC power sources for your L1 L1® Classic, L1® Model I, L1® Model 1S, L1 Model II. Reviewed and updated June 16, 2014.

Electrical Power

As a general note, we want to remind you that all electrical equipment must deal with poor power conditions and power outages. Hardware and software designs can be sophisticated in this regard and we put enormous effort in this area.

At a certain point, if the voltage drops too low from the wall circuit, or there is a power outage, contemporary digital electronics including ours will start a reset sequence. Assuming the AC power recovers, the reset sequence with digital electronics usually takes a few seconds. If that few seconds is longer than the power outage, it can be a frustrating wait.

There are practical things that musicians can do that will minimize the chance of an interruption in their performances – practices that are valuable to know and use in general for all stage equipment.

  • Use AC extension cords that are as short as possible. Do not use a 100’ cord when a 25’ cord will do.
  • Do not use thin-gauge or flimsy extension cords. Good cords are worth the extra expense.
  • Avoid the practice of stringing AC extension cords together: if you have 20’ to the wall socket, use one 25’ cord rather than 3 x 8’ cords. The reason is that the electrical connectors at the junction between cords can introduce extra resistance, especially if they are bent or corroded.
  • Split power-hungry equipment (amplifiers and lights) over as many different power circuits as you can. Lots of power-hungry equipment loaded onto one circuit will lower the voltage and can cause equipment resets and failures, especially in very loud musical performances.
  • Check for non-performance-related equipment on stage circuits that may contain compressors or large motors: refrigerators, air conditioners, snow cone machines, etc. can cause a large drop in the voltage. If possible, move these appliances to other circuits or have them turned off during the performance.


Source: Bill-at-Bose

Surge Protectors

From Hilmar-at-Bose

Surge protectors are not a bad thing, although the Power Stands for the L1 Classic, Model I, Model 1S, Model II and Compact have built in surge protection.

"Surge" means a lot of voltage coming through the power over a short period of time. That's pretty rare and the main cause is lightning, some accidents involving power lines (mostly on poles) being cut and touching something they shouldn't (e.g. the wrong side of a power transformer) and some really big compressors (e.g. industrial-sides freezers or fridges) turning on or off.

With the exception of lightning and some very bad power accidents, the Power Stand can handle that all fine by itself. With lightning, anything is possible. No piece of equipment that I know will survive a direct hit into a directly connected power line. But then again lightning might strike a few blocks (and transformers) away in which case a surge protector might be able to take the first hit and die quickly enough to protect the attached equipment.

In this regard even cheap surge protectors will work fairly well and there is only a really small number of cases where a cheap and very expensive surge protector might make a difference.

On a side note, its a good idea to have all equipment that connects to the Power Stand on the same power strip. That helps with ground loops. On the other hand it's not a good idea to turn things on and off with the switch on the power strip. That may cause your fuse to blow (due to the so-called "in-rush current") and might result in pops and clicks.

The proper way to turn things on is to follow the signal, i.e.

  1. instruments
  2. outboard effects processors
  3. Power Stand
  4. external power amps (e.g. third party power amps)

Turning off be done in reverse.

Source: Hilmar-at-Bose

Power Strips

There is no technical reason why a power strip, a power cord or any sort of power conditioner should make a difference. Our system (and many others too) are designed to deal with all sorts of AC power fluctuation and have high quality internal regulators. These regulate with much higher precision that any external device could do anyway, so "conditioning" or "cleaning" up the AC power doesn't make any audible difference whatsoever.

Source: Hilmar-at-Bose

Power Conditioning

We do not recommend external voltage regulators because we found that in many cases they cause more harm than help. The amps and power supplies in the L1 use highly efficient switching technology, Many voltage regulators are not a good fit for this technology since they are simply not fast enough.

Source: Hilmar-at-Bose



We Bose designers do not believe that a power conditioner provides more headroom, dynamics, better sound, or more fidelity for our equipment.

There are a number of technical reasons for this that I won't go into online, but a good way to think of it is that we have already put in all the power conditioning required to make the products sound as good as possible.


Source: Bill-at-Bose ST 09:09, 12 August 2008 (EDT)

Reviewed with L1® Support June 16, 2014 ST 11:27, 16 June 2014 (EDT)