Bose Dm8s Surface-mount Loudspeakers Instruction Manual (+ PDF)

DM8S Surface-mount Loudspeakers
Design Guide

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5 Documents / Resources

5.1 References

6 Related Posts

Overview

Introduction
Using this design guide, you will be able to create designs for applications that utilize surface-mount loudspeakers. We offer additional design guides for pendant-mount and in-ceiling loudspeakers, as well as dedicated design guides for EdgeMax and FreeSpace 3 sub-satellite systems. To learn more about our loudspeakers and technology capabilities, as well as access additional trainings and tutorials, visit proedu.Bose.com/learn.
System Design Resources
In addition to this guide, we offer the following tools at PRO.BOSE.COM on the software and individual loudspeaker product pages:

Bose Modeler: advanced acoustical design simulation tool, with direct and reflected energy, and Speech Transmission Index (STI). Free at pro.Bose.com/modeler
Bose Business Music System Designer: Web-based auto-loudspeaker layout tool. Free at pro.Bose.com/BMSD
EASE .gll files: for use in the AFMG EASE application, and the EASE GLL Viewer application. EASE allows the simulation of reverberation times, speech intelligibility, and other acoustical parameters. EASE is a paid download. EASE GLL Viewer is free.
EASE Address files: for use in the AFMG EASE Address (2D tool, direct field coverage) or EASE Evac. EASE Address is free.
BIM files: includes the Revit format. Revit is a paid download.

Overview
All system designs begin with a set of requirements. The system requirements can be as simple as, “it has to sound great” or as detailed as, “it must play background-level music at 5 dB above the ambient noise level of the restaurant’s main dining room, which is 65 dB.” The challenge is to gather the right set of requirements, and then turn them into a set of criteria that you can use to create your design. It is important to remember that you are the designer and should use your own intuition and decision skills when planning a project in addition to calculations. Applications with mounting heights up to 10 meters (32 feet) are supported through the surface-mount loudspeaker models listed in this guide.
There are four key requirements that need to be identified to deliver the right system:
Loudness: What sound pressure level (SPL) is required for this application?
Mounting Height: What loudspeakers will work best for my planned mounting height?
Response: What bandwidth is required for the type of program material that will be used?
Coverage: How consistent must the sound be across the entire coverage area?
Each of these requirements can be easily converted into a specification that we can use to create our system design. If we understand the customer’s needs in these four areas, we can deliver a design that will—at a minimum—meet their needs and—at best—exceed their expectations.
For the purposes of this design guide, we will assume that you are familiar with the system requirements for a commercial audio system and are ready to focus on loudspeaker selection, creation of a loudspeaker layout, and defining the necessary amplifier power needed to power the design.
Design Guidelines
When creating a design, you should consider the following:

Mounting Height
Maximum SPL for the application (for example 70 dB-SPL, Z-weighted)

Design Worksheet

Use the following worksheet to create a design using Bose Professional loudspeakers.
Choosing a Model
Step 1: Loudness
Maximum SPL Capability
Confirm that your chosen loudspeaker model will meet your loudness requirement. Find your mounting height and follow the column down until you reach your desired maximum continuous output level. Models with a higher sensitivity and higher tap settings will be able to play at higher levels. Individual model tap charts are available at the end of this document.
Example: For a mounting height of 5 meters (16 feet) in a project that requires 90 dB, you would choose FS4SE.

Surface-mount Models: Maximum Continuous Output Level
Mounting Height	m	2.4	2.7	3	3.7	4	4.3	5	5.5	6	6.7	8	9.8
	ft	8	9	10	12	13	14	16	18	20	22	26	32
DM3SE	25W tap	97	94	93	90	89	88	86	84	83	82	80	78	dB-SPL
FS2SE	16W	98	96	94	91	90	89	87	85	84	83	81	79
FS4SE	40W	102	100	98	95	94	93	91	89	88	87	85	83
DM5SE	50W	103	100	99	96	95	94	92	90	89	88	86	84
DM6SE	80W	106	104	102	99	98	97	95	93	92	91	89	87
DM6SE	8Ώ	107	104	103	100	99	98	96	94	93	92	90	88
DM8S	80W	110	107	102	99	98	97	95	93	92	91	89	87
DM8S	8Ώ	112	109	107	104	103	102	101	99	98	97	95	93

Note: The above table assumes standing ear height at 1.5 meters (5 feet), in standard-spacing (minimum overlap) configuration. Room reverberation could add as much as 4 dB system gain, which is not factored into the measurements above. Use of the transformer on 70/100V systems will introduce an insertion loss of 1 to 2 dB.
Step 2: Mounting Height
Average Coverage and Woofer Sizes
Smaller woofer models have wider average coverage and provide better results at low mounting heights.
Larger woofer models with narrower average coverage angles are better suited for higher mounting heights.
Choose the models that will work with your mounting heights and rule out the other models.

Design Worksheet

Woofer Size	Model	Sensitivity (dB)	Highest Tap / Power Handling	Recommended Mounting Heights
2″–4″	FS2SE	87	16W	2.5 m–6.1 m (8’–20′)
	DM3SE	86	25W
	FS4SE	89	40W
5″–8″	DM5SE	89	50W	3 m–10 m (10’–32′)
	DM6SE (70/100V)	90	80W
	DM6SE (8Ώ)	90	100W
	DM8S (70/100V)	93	80W
	DM8S (8Ώ)	93	125W

Step 3: Response
Confirm that the chosen loudspeaker will meet your low frequency response requirement.

Vocal-range	Low Frequency (–10 dB)	Full-range	Low Frequency (–10 dB)	Extended- range	Low Frequency (–10 dB)
FS2SE	83 Hz	FS4SE	70 Hz	FreeSpace 3 system	40 Hz
DM3SE	75 Hz	DM5SE DM6SE DM8S	65 Hz 59 Hz 52 Hz	Any vocal- range or full-range loudspeaker combined with DM10S-SUB subwoofer	35 Hz

Step 4: Coverage
Determining Loudspeaker Quantity and Spacing
The goal is to fill a rectangle-shaped room with coverage circles at your desired density. Using the graph paper on the last page, create a sketch layout of the room. Using your sketch of the room, follow the steps below to create a layout with the loudspeaker spacing that meets your coverage requirement. Calculators or software can simplify this process. Medium-sized or larger distributed installed systems for background music or voice typically have four or more surface-mount loudspeakers in a room. Use Loudspeaker Spacing Distance (LSD) for small rooms that only need one.

For small rooms such as bathrooms, you may only need one or two loudspeakers to cover the room; look at LSD
A. Calculate the Loudspeaker Spacing Distance (LSD)
We have found the following LSDs work for most applications. For more precise results, and to adjust for obstructions, use Bose Modeler, EASE, EASE Address, EASE Evac, or another calculator.
Note: For a fast average, start with 15 meters (44 feet) edge-to-edge, 10 meters (32 feet) minimum overlap, 8 meters (26 feet) center-to-center for LSD.

Loudspeaker Spacing Distance (LSD)
Mounting Height		Listener Position		Standing 5 ft \| 1.5 m				Sitting 3.5 ft \| 1 m
ft	m	Recommended Downward Pitch	Density	FS2SE DM3SE FS4SE		DM5SE DM6SE DM8S		FS2SE DM3SE FS4SE		DM5SE DM6SE DM8S
				ft	m	ft	m	ft	m	ft	m
8	2.4	0°	Edge-to-edge	15	5	16	5	24	7	22	7
			Minimum Overlap	10	3	10	3	16	5	14	4
			Center-to-center	8	2	7	2	9	3	12	4
10	3.0	0°	Edge-to-edge	26	8	24	7	32	10	32	10
			Minimum Overlap	18	5	16	5	22	7	20	6
			Center-to-center	13	4	11	3	15	5	16	5
12	3.7	–15°	Edge-to-edge	34	10	30	9	40	12	35	11
			Minimum Overlap	21	6	20	6	26	8	24	7
			Center-to-center	17	5	15	5	19	6	17	5
14	4.3	–15°	Edge-to-edge	42	13	38	12	46	14	43	13
			Minimum Overlap	28	9	24	7	29	9	30	9
			Center-to-center	21	6	17	5	23	7	23	7
15	4.6	–30°	Edge-to-edge	42	13	36	11	46	14	40	12
			Minimum Overlap	28	9	24	7	30	9	28	9
			Center-to-center	23	7	19	6	25	8	23	7
16	4.9	–30°	Edge-to-edge	46	14	40	12	50	15	46	14
			Minimum Overlap	28	9	28	9	32	10	30	9
			Center-to-center	23	7	21	6	25	8	25	8
18	5.5	–45°	Edge-to-edge	48	15	42	13	52	16	46	14
			Minimum Overlap	32	10	30	9	33	10	32	10
			Center-to-center	25	8	23	7	29	9	25	8
20	6.1	–45°	Edge-to-edge	52	16	48	15	55	18	52	16
			Minimum Overlap	33	10	34	10	39	12	36	11
			Center-to-center	27	8	28	9	32	10	29	9
22	6.7	–45°	Edge-to-edge	55	18	54	16	55	20	55	18
			Minimum Overlap	41	12	36	11	46	14	40	12
			Center-to-center	33	10	31	9	35	11	33	10
24	7.3	–45°	Edge-to-edge	55	20	55	18	55	23	55	20
			Minimum Overlap	43	13	42	13	50	15	44	13
			Center-to-center	37	11	35	11	39	12	35	11
26	7.9	–45°	Edge-to-edge	55	23	55	20	55	24	55	22
			Minimum Overlap	44	13	44	13	52	16	50	15
			Center-to-center	37	11	39	12	43	13	41	12
28	8.5	–45°	Edge-to-edge	55	23	55	22	55	24	55	23
			Minimum Overlap	44	13	50	15	55	17	53	16
			Center-to-center	37	11	41	12	44	13	41	12

Edge-to-edge coverage can provide fidelity in fixed-location seating/standing and can generally work well for installations on a budget. It also works well for ambient-level and low-level background music. Center to-center installations will have higher density and can accommodate people listening in many different positions and moving floor plans due to uniform coverage. They will also have fewer dead zones. Minimum overlap (or center-to-center) may also be needed if critical communication is happening over the system. Bose Modeler or EASE Evac can help with speech intelligibility evaluation.
B. Place the first loudspeaker at ½ LSD from any corner of the room. Continue to place loudspeakers along the wall at LSD. Supported room width can be up to 2× LSD, assuming loudspeakers are facing in from each opposing wall as shown.

C. After the last loudspeaker is placed, center the loudspeakers in that row to create new offset distances out from each corner, which may be unique from ½ LSD.
Subwoofers: Quantity and Placement of Subwoofers
The number of subwoofers to use, where to position them, and how loud to set them can vary depending on the individual situation. Details such as placement, boundary loading, room size, coupling quantity of multiple loudspeakers to subwoofers, type of music, type of activity, budget, and the expectations of the listeners should all be considered. The following guidelines are general rules to follow.

Add one subwoofer for every group of four vocal- or full-range loudspeakers.
Subwoofer spacing should be as far apart as is practical. 12.2 meters (40 feet) or greater subwoofer-to subwoofer spacing distance within the same zone is desirable.
When the suggested subwoofer count is two within a single zone, it may be preferable to use either one in a corner to avoid audible interference; or increase the count to three, which creates more audible interference locations but limits them to smaller sizes where the reverberant field (added room reflections) tends to mask them.
Placing a ceiling subwoofer within 0.9 meters (3 feet) of a wall increases its output by 3 dB. Placing it within 0.9 meters (3 feet) of a corner increases its output by another 3 dB (6 dB total) and also reduces reflections that can create audible interference (bass cancellations) in the listening area.
Listening positions located below the subwoofer should be supported by a nearby vocal- or full-range loudspeaker to provide better tonal balance in the low-frequency pressure zone.

Step 5: Calculate Required Amplifier Size
All FreeSpace FS and DesignMax loudspeakers are compatible with 70-volt, 100-volt, and low-impedance amplifiers.
Use the Tap Charts to determine which loudspeaker tap is required for this design
A. Locate the loudspeaker tap chart and find the column for mounting height for this design.
B. Follow the column to the desired maximum SPL.
C. Follow the row across the chart to determine the required loudspeaker tap.
D. Calculate the required amplifier power:Amplifiers: Example Amplifier Configurations
Modern amplifiers come in a variety of channel counts and configuration options to allow for different output configurations, zoning options, and varying loudspeaker quantities. A properly optimized system may only need a low 1- or 2-watt tap setting to achieve 70 dB in a typical room. The below example lists how many FS2SE loudspeakers can be handled at the loudspeaker’s highest 70/100V tap setting.

FreeSpace FS2SE Loudspeaker Amplifier Example	Maximum Loudspeakers at Higher Tap Settings	EQ Preset
FreeSpace IZA 190-HZ	5 at 16W, 10 at 8W tap	FS2C/SE/P
FreeSpace IZA 2120-HZ	6 at 16W, 13 at 8W	FS2C/SE/P
Power Share PS404D	22 at 16W, 45 at 8W	FS2SE
Power Space P4150+	8 at 16W, 17 at 8W	FS2SE

Smart Bass: Application of Smart Bass processing
If your design is using a Power Space+ amplifier; or your design utilizes a dedicated Bose DSP, such as the Commercial Sound Processor CSP models; or any of the Control Space ESP or EX models; you have the option of applying Smart Bass to your loudspeaker output channel. This uses Bose EQ presets, dynamic EQ, and excursion limiting tuned to each model and room calibration. This will prevent lower background-level music from sounding thin, but also ensures the sound is consistent at various SPL levels. At louder levels, Smart Bass also allows for more musical limiting than traditional voltage limiters.

Tap Charts

Individual Loudspeaker Continuous Output Level
Note: The following tap charts assume standing ear height at 1.5 meters (5 feet) in standard spacing. Room reverberation could add as much as 4 dB system gain, which is not factored into the measurements. Designing without room gain will ensure you don’t under-plan your design, and amp attenuation is possible at the job site if you exceed the average room SPL target during measurement. Values below 70 dB are omitted, select a higher tap.
DM3SE

DM3SE (standing listener height)
Mounting Height	m	2.4	2.7	3	3.7	4	4.3	5	5.5	6	6.7	8	9.8
	ft	8	9	10	12	13	14	16	18	20	22	26	32
TAP	3W	88	85	83	80	79	78	77	75	74	73	71	69	dB-SPL
	6W	91	88	86	83	82	81	80	78	77	76	74	72
	12W	94	91	89	86	85	84	83	81	80	79	77	75
	25W	97	94	93	90	89	88	86	84	83	82	80	78
	8Ώ	97	94	93	90	89	88	86	84	83	82	80	78

FS2SE

FS2SE (standing listener height)
Mounting Height	m	2.4	2.7	3	3.7	4	4.3	5	5.5	6	6.7	8	9.8
	ft	8	9	10	12	13	14	16	18	20	22	26	32
TAP	1W	86	83	82	79	78	77	75	73	72	71	—	—	dB-SPL
	2W	89	87	85	82	81	80	78	76	75	74	72	70
	4W	92	90	88	85	84	83	81	79	78	77	75	73
	8W	95	93	91	88	87	86	84	82	81	80	78	76
	16W	98	96	94	91	90	89	87	85	84	83	81	79
	8Ώ	98	96	94	91	90	89	87	85	84	83	81	79

FS4SE

FS4SE (standing listener height)
Mounting Height	m	2.4	2.7	3	3.7	4	4.3	5	5.5	6	6.7	8	9.8
	ft	8	9	10	12	13	14	16	18	20	22	26	32
TAP	2.5W	90	87	86	83	82	81	79	77	76	75	73	71	dB-SPL
	5W	93	90	89	86	85	84	82	80	79	78	76	74
	10W	96	93	92	89	88	87	85	83	82	81	79	77
	20W	99	96	95	92	91	90	88	86	85	84	82	80
	40W	102	100	98	95	94	93	91	89	88	87	85	83
	8Ώ	102	100	98	95	94	93	91	89	88	87	85	83

DM5SE

DM5SE (standing listener height)
Mounting Height	m	2.4	2.7	3	3.7	4	4.3	5	5.5	6	6.7	8	9.8
	ft	8	9	10	12	13	14	16	18	20	22	26	32
TAP	3W	91	88	86	83	82	81	80	78	77	76	74	72	94
	91	94	91	89	86	85	84	83	81	80	79	77	75
	12W	97	94	92	89	88	87	86	84	83	82	80	78
	25W	100	97	96	93	92	91	89	87	86	85	83	81
	50W	103	100	99	96	95	94	92	90	89	88	86	84
	8Ώ	103	100	99	96	95	94	92	90	89	88	86	84

DM6SE

DM6SE (standing listener height)
Mounting Height	m	2.4	2.7	3	3.7	4	4.3	5	5.5	6	6.7	8	9.8
	ft	8	9	10	12	13	14	16	18	20	22	26	32
TAP	2.5W	91	88	87	84	83	82	80	78	77	76	74	72	dB-SPL
	5W	94	91	90	87	86	85	83	81	80	79	77	75
	10W	97	94	93	90	89	88	86	84	83	82	80	78
	20W	100	97	96	93	92	91	89	87	86	85	83	81
	40W	103	101	99	96	95	94	92	90	89	88	86	84
	80W	106	104	102	99	98	97	95	93	92	91	89	87
	8Ώ	107	104	103	100	99	98	96	94	93	92	90	88

DM8S

DM8S (standing listener height)
Mounting Height	m	2.4	2.7	3	3.7	4	4.3	5	5.5	6	6.7	8	9.8
	ft	8	9	10	12	13	14	16	18	20	22	26	32
TAP	2.5W	95	92	87	84	83	82	80	78	77	76	74	72	dB-SPL
	5W	98	95	90	87	86	85	83	81	80	79	77	75
	10W	101	98	93	90	89	88	86	84	83	82	80	78
	20W	104	101	96	93	92	91	89	87	86	85	83	81
	40W	107	104	99	96	95	94	92	90	89	88	86	84
	80W	110	107	102	99	98	97	95	93	92	91	89	87
	8Ώ	112	109	107	104	103	102	101	99	98	97	95	93

Bose Dm8s Surface-mount Loudspeakers Instruction Manual

Overview

Design Worksheet

Tap Charts

Graph Paper

References

Documents / Resouces

Related Manuals