From Bose Pro Encyclopedia FAQ & Wiki
 How to Tell the Difference Between L1 Models
This is how to tell which L1® unit you have.
|2003 - 2007||Rounded front. The Output Panel has Amp1 Out, Amp2 Out, Amp3 Out|
|2007 - 2012||Rounded front. The Output Panel has no outputs for Amp1, Amp2, Amp3.
The Output Panel and L1 Cylindrical Radiator® loudspeaker sections have orange L1® markers.
|2012 - Present||Extending legs, one Cylindrical Radiator® (Top Array), Bottom Extension|
|2007 - Present||Extending legs, two Cylindrical Radiator®s, Bass Line Out,|
|2003 - Present||Up to two per Power Stand (above). More if using the PackLite® power amplifier model A1. 2 x 5.25" drivers, 26.6 lb|
|2012 - Present||Up to one per Power Stand (above). More if using the PackLite® power amplifier model A1. 2 x 10" drivers 45 lb. 3 position switch.|
|2005 - Present||Allows bass expansion for L1® Classic L1® Model I L1® Model II (not L1® Compact not L1® Model 1S)|
|2007 - Present||T1 ToneMatch® Audio Engine|
|2009 - Present||Integrated Power Stand and Bass Unit, two Extensions|
L1® Classic is the name now used to describe the first L1 Cylindrical Radiator® loudspeaker introduced in the United States, in October 2003.
The Classic remained in production until 2007 when it was replaced by the L1® Model I.
Visually and acoustically the L1 Classic is almost identical to the Model I, with only a few notable differences.
The serial number for any Classic tower should start with 032495 .
 Comparison of the Classic to the Model I
 Acoustical Output
In the L1® Classic, the L1 Cylindrical Radiator® loudspeaker is powered by two (2) 250 Watt amplifiers. In the Model I and Model II, the L1 Cylindrical Radiator® loudspeaker is powered by one (1) 250 Watt amplifier. The Classic, the Model I, and the Model II all use a second 250 Watt amplifier to power one or two B1 bass modules (update: or a single B2 Bass Module).
Although these numbers serve as a point of reference they do not tell the whole story. During the design of the L1® Model I and the L1® Model II the impedance of the L1 Cylindrical Radiator® loudspeaker was lowered. As a result of the lower impedance, a single 250W amplifier now powers the system to within 1.75 dB of the max SPL of the L1® Classic. Several other changes were made to the signal processing and acoustical sections to further reduce this small difference. Particular attention was paid to this change and many A/B comparisons were conducted by Bose to confirm that there was no significant audible difference between the two systems.
— Source: Ken-at-Bose, Neil-at-Bose
 Power Stand Connections
L1® Classic shipped between 2003 and 2005
The L1 Classic had features built into its input/output panel that allowed the three amplifiers to be used separately as power amplifiers. For example, up to six B1 Bass Modules could be driven from an auxiliary Power Stand. See: Classic Extended Bass Package
The input/output panel as it appeared in units shipped between 2003 and 2005 is shown.
- On the right side of the input/output panel, there are inputs for
- All Amps In
- Amp 1 In
- Amp 2 In
- Amp 3 In
- And outputs for
- Amp 1 Out
- Amp 2 Out
- Amp 3 Out (used for B1 Bass Modules)
L1® Classic shipped between 2006 and 2007
 Detailed View of Input / Output Panel for 3 Amps
Note: All white inputs are unbalanced (Amp 1, Amp 2, Amp 3 ,All Amps In)
The L1® Model I uses a simpler input/output panel
- Dropped Amp 1 out, Amp 2 output found on the L1® Classic
- Identified by orange labels and L1® logo
- RoHS compliant.
- Shipped with Presets 3.0 installed.
 L1® Model I Orange MarkingsL1® Model I has orange L1® Markings on the Power Stand and the L1 Cylindrical Radiator® loudspeaker sections. The other Models do not have these.
L1 Cylindrical Radiator® loudspeaker sections
 Downloads for the L1 Classic
- Version 3.0 Presets Read instructions carefully.
- Version 2.0 Presets and Firmware Updates (bundled into one download)
 Lower Section Only
Q: Can I run with only the lower section of the L1 Cylindrical Radiator® loudspeaker?
A: From a technical standpoint it is safe to operate the system with only the lower section of the L1® Classic , however the spatial and spectral performance of will be greatly reduced, so this has only a very limited application. - Hilmar-at-Bose
 Correcting the Tone
Try inserting a ¼ inch connector in the Bass Line Out of the Power Stand. This will cause the internal logic to reduce the Bass output, and this should give you a better overall tonal balance when running with only one section of the L1® Classic.
For very detailed notes about this see Half Stack.
 Holistic View
A Holistic View of the L1® 
Here is one way you can think about the L1® System.
 L1 Cylindrical Radiator® loudspeaker as one loudspeaker
Think of the L1 Cylindrical Radiator® loudspeaker (Yellow highlight) is a single loudspeaker with 24 drivers (2.5 inch) supplied by 500 watts for the L1® Classic and 250 watts for the L1® Model I. Note: the L1® Model I provides the same audible output. It is just more efficient than the L1® Classic.
 Two B1 Bass Modules as a one bass loudspeaker
That's 750 watts in total for the L1® Classic and 500 watts total for the L1® Model I
Note: This information below is applicable to the L1® Classic and not the L1® Model I
The L1 Cylindrical Radiator® loudspeaker This is one loudspeaker that happens to break down into two pieces for travel. This is driven by two separate amps, but this is not important because under normal circumstances both amps are driven identically. One drives the top half of the L1 Cylindrical Radiator® loudspeaker and the other drives the bottom half. Because the L1 Cylindrical Radiator® loudspeaker should always be operated as a single unit, what happens when you break it down isn't relevant.
If you don't use the B1 Bass Modules at all, the amp that is normally used to drive them is idle.
 Use the proper cablesB1 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.
Please click the picture above for ordering information.
You may also use high quality NL4 cables (four conductor cables). Alternate and longer cables for B1s
 Model IL1® Model I handles the B1s the same way, but with a more efficient design provides the same audible output from the L1 Cylindrical Radiator® loudspeaker with a single 250 watt amp.
- ↑ The serial number for any Classic tower should start with 032495. Nick-at-Bose
- ↑ Hilmar-at-Bose talks about using the lower half (only) of the L1® Cylindrical Radiator in the Bose® Musicians Community Message Boards
- ↑ Originally appeared in the Bose® L1® Systems Users Forum
- ↑ 4.0 4.1 Quoting Hilmar-at-Bose
- ↑ two B1 Bass Module loudspeakers connected draws up to 250 watts at 4 ohms
- ↑ one B1 Bass Module loudspeaker connected draws up to 125 watts at 8 ohms
 Compatibility with Other Members of the L1® Family of Products
 Cylindrical Radiator®s
 Cylindrical Radiator®s are not interchangeable across models
Specifically (and without exception)
- The Cylindrical Radiator speaker sections of the L1® Classic, the L1® Model I and L1® Model 1S and the L1® Model II are not compatible with each other.
- The Cylindrical Radiator speaker sections of the L1® Classic can only be used with the Classic PS1 power stand (no orange markings on the input/output panel).
- The Cylindrical Radiator speaker sections of the L1® Model I (orange markings on the back of both sections) can only be used with the Model I PS1 power stand (orange markings on the input/output panel).
- The Cylindrical Radiator speaker sections of the L1® Model II can only be used with the L1® Model II power stand.
- The Cylindrical Radiator speaker sections of the L1® Model 1S can only be used with the L1® Model 1S power stand.
 T1 ToneMatch® Audio Engine
- The T1 ToneMatch® Audio Engine can be used with the
 PackLite® power amplifier Model A1
 B1 Bass Module
 B2 Bass Module
- The B2 Bass Module can be used with the
- L1® Classic Normal Mode only
- L1® Model I Normal Mode only
- L1® Model 1S all modes
- L1® Model II all modes but L1® Model II Power Stand Firmware version 1.4 or later required