3.5R - Pregnant DEFINITIVE TECHNOLOGY - Free user manual and instructions

Product Type	Bookshelf Speaker
Model	3.5R
Brand	Definitive Technology
Dimensions (H x W x D)	12.5 x 7.5 x 8.25 inches
Weight	12 lbs (5.4 kg) each
Power Handling (RMS)	100 watts
Frequency Response	45 Hz – 25 kHz
Impedance	8 ohms
Sensitivity	89 dB
Driver Complement	1-inch aluminum dome tweeter, 5.25-inch BDSS mid/woofer
Recommended Amplifier Power	20 – 150 watts per channel
Enclosure Type	Bass reflex with front-firing port
Finish	Black vinyl
Warranty	5 years limited
Placement	Bookshelf or stand-mounted
Featured Technologies	BDSS (Balanced Double Surround System), Linear Response Waveguide
Cleaning Instructions	Wipe with dry cloth. Do not use solvents or abrasive cleaners.
Safety Precautions	Place on stable surface. Keep away from moisture and heat sources.
Spare Parts & Repairability	Contact authorized dealer for service and parts.
General Information	Designed for high-quality stereo and home theater use.

Frequently Asked Questions - 3.5R DEFINITIVE TECHNOLOGY

What is the recommended placement for the Definitive Technology 3.5R speaker?

Place the 3.5R on a sturdy bookshelf or speaker stand at ear level. Keep at least 6 inches from walls for optimal bass response. Avoid corners to reduce boominess. For best stereo imaging, angle speakers towards the listening position.

Can I use the 3.5R as a surround speaker in a home theater setup?

Yes, the 3.5R is suitable for surround channels. Mount them on stands or shelves behind or to the sides of the listening area. Pair with a subwoofer for full-range sound.

What amplifier power is recommended for the 3.5R?

Definitive Technology recommends an amplifier with 20 to 150 watts per channel. The 3.5R has an 8-ohm impedance and 89 dB sensitivity, so it works well with most receivers.

How do I clean the 3.5R speaker?

Use a soft, dry cloth to dust the cabinet. For grilles, gently vacuum or use a lint roller. Do not apply liquids or cleaners directly to the speaker. Avoid touching the drivers.

What is the warranty period for the Definitive Technology 3.5R?

The 3.5R comes with a 5-year limited warranty covering defects in materials and workmanship. Register your product online for full coverage.

Can I bi-wire or bi-amp the 3.5R?

No, the 3.5R has a single pair of binding posts. It is not designed for bi-wiring or bi-amping. Use standard single-wire connections.

What type of speaker wire should I use?

Use 16-gauge or thicker wire for runs up to 50 feet. For longer distances, use 14-gauge. Ensure polarity is consistent (+ to +, - to -). Avoid speaker wire with excessive capacitance.

Does the 3.5R require a subwoofer?

While the 3.5R produces decent bass down to 45 Hz, a subwoofer is recommended for deep low frequencies and home theater impact. Definitive Technology subwoofers pair well.

How do I break in the 3.5R speakers?

Play music at moderate volume for 20-30 hours to allow the drivers to reach optimal performance. Avoid excessive volume during break-in. The sound will smooth out over time.

Where can I find spare parts for the 3.5R?

Contact Definitive Technology customer service or an authorized dealer for replacement drivers or grilles. Do not attempt repairs yourself; seek professional service.

USER MANUAL 3.5R DEFINITIVE TECHNOLOGY

Di SERIES OWNER'S MANUAL

Models: 3.5R, 4.5R, 5.5R, 6.5R, 8R, 6.5STR, 5.5S and 6.5S

Close-up of a black electronic device with a circular speaker and mechanical components (no visible text or symbols)

Definitive Technology® The Leader in High-Performance Loudspeakers®

Thank You

Thank you for choosing the Definitive Technology Disappearing In-Wall loud speaker. The Di Series products offer extraordinary sound quality from speakers that are barely visible when installed in a wall or ceiling. Our engineers spent many years developing this product. In order to ensure that you experience the finest performance possible, we encourage you to take a moment to fully read this owner's manual and familiarize yourself with the proper installation and set-up procedures for your Di Series speaker.

Unpacking Your Disappearing In-Wall Speakers

Please Inspect For Shipping Damage

Each loudspeaker leaves our plant in perfect condition. Any visible or concealed damage most likely occurred in handling after it left our plant and should be reported at once to your Definitive dealer or the delivery company that delivered your loudspeaker. Please unpack your system carefully. Save all cartons and packing materials in case you move or need to ship your system. Record the serial number found on the back of the speakers, and on the carton, in this manual and save it for future reference should your speaker need service. For your best protection, register your Di Series products on-line at http://registration.definitivetech.com.

Definitive Technology

Di Series

Definite Componenting* initial

Di 3.5R

Circular diagram with concentric rings and central cross-section, no text or symbols present

Di 4.5R Di 5.5R

Definitive Climatic* 100%

- (D) + Definition (1000000000000000000000000000000000000000000000000000000000000000000000000000000

Di 6.5R

+ - (a) Definite Dedentary's kind

Capacitor Davon

Di 5.5S

Technical diagram of a circular mechanical component with labeled parts and concentric rings

Di 6.5S

Painting Di Series Speakers

Your Di Series speakers may be painted to match the color of the wall or ceiling in which they are installed. Failure to follow the following painting instructions may result in seriously degraded sound quality. It is your responsibility to make sure your painting contractor sees and follows these instructions.

1. DO NOT PAINT THE GRILLE WITH A BRUSH OR ROLLER — they will clog the fine mesh of the grille and cloth scrim and result in poor sound quality.
2. Remove the grille from the speaker and place it on a drop cloth, newspaper or plastic sheet.

3. The grille MUST be spray painted with one of the following:

4. Spray paint that closely matches the desired finish/color

5. A custom spray bomb, color matched to your paint finish

6. Indoor latex paint using a spray gun (paint must be diluted to the paint manufacturer's specifications)

7. Removing the backing cloth (scrim) is not required.

8. Paint should be applied in a series of thin coats sprayed at approximately 60 degrees from the grille surface, allowing each coat to fully cure before applying additional coats.

9. To ensure that the paint distribution is evenly applied, each coat should be applied from at least 4 different directions to the grille. (N, S, E & W) This will ensure an even coverage on the grille.
10. Once the grille has been painted and the paint has fully cured, you may use a brush, or small roller to touch-up the outer edge of the grille frame — being VERY careful not to get any additional paint on the grille mesh surface.

Optional Fire-Rated Enclosures

Definitive Di Series speakers have been designed to meet UL 1480 and 2043 standards when used with the appropriate optional Definitive fire-rated enclosures. All plastic parts used in the speakers are V0 flame rated as per UL 94.

While these enclosures are necessary in most countries for commercial and multi-family dwelling installations, residential customers may want to use them for added safety and/or to reduce the sound from "leaking" into adjacent rooms.

Placement Options

Definitive Technology Di Series Loudspeakers give you nearly endless placement options. But remember that placement choice for your in-wall speakers bears careful consideration, as installation requires that you cut a hole in your wall or ceiling! Fill a room with sound by installing in-wall speakers in nearly any wall or ceiling location although it is best to keep the speakers at least 2 feet (60 cm) from side walls [Figure 1]. When using Di Series models in home theater applications follow the guidelines [illustrated in Figures 2, 3 and 4]. Definitive Di Series In-Wall Loudspeakers have aimable tweeters that allow you to focus their sound toward or away from your listening area depending on the application.

Recommended speaker distance from side walls is 2 feet (60cm).

Figure 1

1-2 ft. (32-60cm) 1-2 ft. (32-60cm) recommended height 3'-6' 1-2m

Figure 2

OPTION 1 OPTION 2 6.1 Surround

Figure 3

graph TD
    A[" "] --> B[" "]
    C[" "] --> D[" "]
    E[" "] --> F[" "]
    G[" "] --> H[" "]
    I[" "] --> J[" "]
    K[" "] --> L[" "]
    M[" "] --> N[" "]
    O[" "] --> P[" "]
    Q[" "] --> R[" "]
    S[" "] --> T[" "]
    U[" "] --> V[" "]
    W[" "] --> X[" "]
    Y[" "] --> Z[" "]
    AA[" "] --> AB[" "]
    AC[" "] --> AD[" "]
    AE[" "] --> AF[" "]
    AG[" "] --> AH[" "]
    AI[" "] --> AJ[" "]
    AK[" "] --> AL[" "]
    AM[" "] --> AN[" "]
    AO[" "] --> AP[" "]
    AQ[" "] --> AR[" "]
    AS[" "] --> AT[" "]
    AU[" "] --> AV[" "]
    AW[" "] --> AX[" "]
    AY[" "] --> AZ["7.1 Surround Option"]
    BA[" "] --> BB["6.1 Surround Option"]

Figure 4

graph TD
    A["Central Component"] --> B["Outer Ring"]
    B --> C["Inner Ring"]
    C --> D["Outer Ring"]
    D --> E["Feedback Loop"]
    E --> F["Definite"]
    style A fill:#f9f,stroke:#333
    style B fill:#ccf,stroke:#333
    style C fill:#cfc,stroke:#333
    style D fill:#fcc,stroke:#333
    style E fill:#ffc,stroke:#333
    style F fill:#cff,stroke:#333

Figure 5
Point tweeter in desired direction by turning the tweeter assembly.

Simple line drawing of a mechanical component with an arrow indicating upward motion (no text or symbols)

Figure 6a
Push gently in direction of arrow to set angle.

Figure 6b

Symmetrical concentric oval diagram with decorative border and central circular pattern (no text or symbols)

Aiming the Tweeter

A tweeter aimed toward your listening position improves imaging and detail. To aim the tweeter, first install the speaker in the desired location. Rotate the tweeter so that the arrow on the tweeter faceplate is pointing in the direction you wish to aim the tweeter [Figure 5] then gently push the tweeter in that direction [Figure 6]. When using Di Series In-Wall Loudspeakers as front/main home theater speakers or as stereo speakers in a distributed audio system aim the tweeter toward the main listening position. For rear/surround speakers installed in walls or ceilings, aim the tweeter toward the nearest reflecting surface (an adjacent wall or ceiling) for a more diffuse sound field (if you so desire; for more direct sound, aim the tweeters at your listening position).

Environmental EQ

(not included on Di 3.5R and Di 4.5R models)

If your listening room is very reflective, with smooth sheetrock walls, hardwood floors, and non-cushioned furniture, the sound will be overly "bright" and unnatural. Engaging the Environmental EQ feature [Figure 7] (by selecting the "-" setting) compensates for the effect of overly loud treble. If your room is has a lot of absorbing surfaces such as over-stuffed furniture, heavy drapes and rugs such that the speakers sound "dull," engage the "+" setting to boost treble response. Leave the switch in the center position in rooms with a balance of reflecting and absorbing surfaces (most rooms fall into this category). Note: the Di 6.5STR has a two position switch; the minus symbol "-" represents normal treble output and the plus symbol "+" represents treble boost.

- 0 + ENVIRONMENTAL EQ

Figure 7

Installation

Installation Cautions

Installation of Disappearing Series Loudspeakers requires skills in using tools such as a drill, screwdriver, saws and power tools. Installation also entails running wires through walls. You should have a thorough understanding of local building and fire codes and a familiarity with the area behind the wall or ceiling into which you plan to install your speakers.

When cutting holes in and running wires through walls/ceilings you run the risk of cutting electrical wires or water pipes thereby causing safety hazards and property damage. If you are in any doubt that you possess the necessary skills or tools, contact your Definitive Technology dealer, general contractor or a professional installer.

Required Tools

• Pencil for marking the location of installation.
• Bubble level (for Di 5.5S and Di 6.5S models only)
  • Keyhole saw, utility knife or material- appropriate incising implement for cutting drywall or other wall material.
  • Phillips head screwdriver.
• Power drill with appropriate bit (optional, for starting wall cut).

Installation Procedure

- You must first install speaker wires that meet appropriate building and fire codes before installing the speakers. Use at least 18 gauge wire or heavier to ensure optimum sound quality.

Definitive Technology

• Make sure the material into which you plan to mount the speakers (plaster, drywall, paneling, stone, etc.) can support the weight of the speakers (see specification page for the weight of your model).
• Make sure the locations you select do not conceal studs, electrical wiring or plumbing. Prior to installation, hold the speaker with grille on in your chosen

location to make sure it safely clears obstacles such as studs, comers, beams, lighting fixtures and door/window frames. Your cutout must be at least 2" (50 mm) from adjoining walls or ceiling, internal studs or plumbing.

• Using the supplied template, trace the installation location with a pencil. You can do this by holding the template in your preferred location and tracing around it. In the case of the rectangular models (Di 5.5S and Di 6.5S) use a bubble level to square and level the template. [Figures 8 & 9]
• Carefully cut the hole with the appropriate cutting tool for your wall or ceiling material. Start the hole by drilling a hole on the inside of the tracing (with the drill bit just inside the line). Use this hole to insert the saw or knife and begin cutting [Figure 10]. The holes for the Di 3.5R and Di4.5R must be cut very precisely as their flanges are only 38 " (9.5 mm) wide. We recommend using hole saws to cut the holes for these models — 312 " for the Di 3.5R and a 412 " for the Di 4.5R.

Template

Figure 8

Left channel wires + - + - Right channel wires

Figure 11b

Template Figure 9

Simple line drawing of a tool interacting with a rectangular block (no text or symbols)

Figure 10
Figure 12

- Once you have cut the hole, pull the speaker wire out of the hole and connect the speaker. Strip ^1/2 " inch (12 mm) of insulation from each of the two conductors of the wire to expose the bare metal and twist each of the conductors into a single unfrayed strand. Note that one of the terminals on the rear of each speaker is marked red (+) and the other black (-). Make certain that you connect the wire from the red terminal (+) of your amplifier or receiver to the red terminal (+) on your speaker and the wire from the black terminal (-) of your amplifier or receiver to the black terminal (-) on your speaker. Most wire has some indicator (such as color-coding, ribbing or writing) on one of the two conductors to help you maintain consistency [Figure 11a]. In the case of the Di 6.5STR single speaker stereo model, both left and right channel speaker wires are connected to the speaker [Figure 11b].

• Push down on the top of the terminal to reveal the wire hole in the side of the terminal post and insert the wire into the hole [Figure 12]. Release the pressure on the terminal to secure the wire.
• Loosen the rotating lock arms by turning the lock arm screws on the front of the speaker counter clockwise 12 to 1 turn, just enough to allow the lock arm to move freely. [Figure 13]. Make sure that the rotating lock arms are flipped inwards [Figure 14] so that your speaker fits into your cutout.

graph TD
    A["Top Component"] --> B["Bottom Component"]
    B --> C["End Caps"]

AMPLIFIEROR RECEIVER Figure 10

Figure 11a

Definitive Technology

• Place the speaker carefully into the cutout. If you have a level, use it to help you correctly align rectangular speaker models. Tighten the lock arm screws with a screwdriver [Figure 15]. This will rotate the lock arms [Figure 16] and secure the speaker to the wall/ceiling. Do not over-tighten the lock arm screws. If you are using a powered screwdriver or drill set the torque to a value of 7 in. - lb. (8dN - m)
  • Install the grille on the speaker frame. Powerful magnets hold the grille in place.

Lock arm screws. Turn counter clockwise to loosen.

Figure 13

Lock arms tucked in prior to installing speaker in wall.

Figure 14

Lock arm screws. Turn clockwise to tighten lock arms and secure speaker to surface.

Figure 15

Top-down schematic of a circular mechanical component with internal components and a directional arrow (no text or symbols)

Figure 16

SAFETY FIRST

When installing your Di Series In-Wall Loudspeakers, be aware of the weight of your particular model (see specification page for the weight of your model) and the sturdiness of the material into which you are installing the speaker. Also be aware of any concealed studs, electrical wiring or plumbing in the wall or ceiling into which you are installing the speakers. If you are not sure of a safe way to install these speakers, consult a professional installer, your authorized Definitive Technology dealer, or a building contractor.

Technical Assistance

It is our pleasure to offer assistance if you have any questions regarding your Definitive loudspeakers. Please contact your nearest Definitive Technology dealer or call us directly at [phone] (US & Canada), 01 [phone] (all other countries) or e-mail [e-mail].

Service

Service work on your Definitive loudspeakers will normally be performed by your local Definitive Technology dealer. If your dealer is unable or unwilling to perform service contact us for alternative options. Please note that the address given in this manual is the address of our offices only. Under no circumstances should loudspeakers be shipped to our offices or returned without contacting us first and obtaining return authorization.

Definitive Technology Offices

11433 Cronridge Drive

Owings Mills, Maryland 21117

Phone: [phone] (US & Canada),

01 [phone] (all other countries)

WARNING: LISTEN CAREFULLY

Definitive Technology loudspeakers and subwoofers are capable of playing at extremely high volume levels, which could cause serious or permanent hearing damage. Definitive Technology accepts no liability for hearing loss, bodily injury or property damage resulting from the misuse of its products.

You should limit prolonged exposure to volumes that exceed 85 decibels (dB).

For more about safe volume levels refer to the Occupational Health and Safety Administration (OSIIA) guidelines at: www.osha.gov/dts/osta/otm/noise/standards_more.html.

NOTES

Specifications

		Di 3.5R Di 4.5R	Di 5.5R	Di 6.5R	Di 6.5STR	Di 8R	Di 5.5S	Di 6.5S
Grille Diameter	4-9/16"	(11.6 cm)	5-3/8" (13.55 cm)	7-3/8" (18.62 cm)	8-5/16" (21.04 cm)	8-5/16" (21.04 cm)	9-3/4" (24.76 cm)	—	—
Grille Length		—	—	—	—	—	—	7-3/8" (18.61 cm)	8-5/16" (21.01 cm)
Grille Width		—	—	—	—	—	—	7-3/8" (18.61 cm)	8-5/16" (21.01 cm)
Cutout Diameter		3-3/4" (9.55 cm)	4-1/2" (11.5 cm)	6-5/16" (16 cm)	7-1/4" (18.4 cm)	7-1/4" (18.4 cm)	8-3/4" (22.2 cm)	—	—
Cutout Width		—	—	—	—	—	—	6-5/16" (16 cm)	7-1/4" (18.4 cm)
Cutout Length		—	—	—	—	—	—	6-5/16" (16 cm)	7-1/4" (18.4 cm)
Total Depth *		3" (7.55 cm)	3-3/8" (8.64 cm)	3-5/8" (9.04 cm)	3-5/8" (9.07cm)	3-5/8" (9.07 cm)	3-7/8" (9.77 cm)	3-5/8" (9.04 cm)	3-7/8" (9.70 cm)
Mounting Depth In-Wall **		2-1/2" (6.3 cm)	2-7/8" (7.4 cm)	3-1/16" (7.8 cm)	3-1/16" (7.8 cm)	3-1/16" (7.8 cm)	3-3/8" (8.5 cm)	3-1/16" (7.8 cm)	3-1/16" (7.8 cm)
Woofer		3-1/2" (8.9 cm)	4-1/2" (11.4 cm)	5-1/4" (13.3 cm)	6-1/2" (16.5 cm)	6-1/2" (16.5 cm)	8" (20 cm)	5-1/4" (13.3 cm)	6-1/2" (16.5 cm)
Tweeter		3/4" (20 mm)	3/4" (20 mm)	1" (25 mm)	1" (25 mm)	2 @ 3/4" (20 mm)	1" (25 mm)	1" (25 mm)	1" (25 mm)
Product Weight		1.9 lb. (0.85 kg)	2.6 lb. (1.16 kg)	3.7 lb. (1.67 kg)	3.8 lb. (1.73 kg)	4.4 lb. (2.14 kg)	4.8 lb. (2.14 kg)	3.8 lb. (1.73 kg)	4 lb. (1.79 kg)
Frequency Response		40 Hz – 30 kHz	35 Hz – 30 kHz	28 Hz – 30 kHz	26 Hz – 30 kHz	26 Hz – 30 kHz	26 Hz – 30 kHz	28 Hz – 30 kHz	26 Hz – 30 kHz
Sensitivity		87 dB	88 dB	89 dB	90 dB	90 dB	90 dB	89 dB	90 dB
Impedance		All models are compatible with 4 – 8 Ohm outputs.
Min/Max Recommended Power		10/125	10/150	10/175	10/200	10/125	10/225	10/175	10/200

* From back of mounting flange to deepest part of product
** Total depth when product installed in 1/2" (12.7mm) thick material

LIMITED USA WARRANTY

5-YEARS FOR DRIVERS AND CABINETS, 3-YEARS FOR ELECTRONIC COMPONENTS

DEI Sales Co., dba Definitive Technology (herein “Definitive”) warrants to the original retail purchaser only that this Definitive loudspeaker product (the “Product”) will be free from defects in material and workmanship for a period of five (5) years covering the drivers and cabinets, and three (3) years for the electronic components from the date of the original purchase from a Definitive Authorized Dealer. If the Product is defective in material or workmanship, Definitive or its Authorized Dealer will, at its option, repair or replace the warranted product at no additional charge, except as set forth below. All replaced parts and Product(s) become the property of Definitive. Product that is repaired or replaced under this warranty will be returned to you, within a reasonable time, freight collect. This warranty is non-transferrable and is automatically void if the original purchaser sells or otherwise transfers the Product to any other party.

This Warranty does not include service or parts to repair damage caused by accident, misuse, abuse, negligence, inadequate packing or shipping procedures, commercial use, voltage in excess of the rated maximum of the unit, cosmetic appearance of cabinetry not directly attributable to defects in material or workmanship. This warranty does not cover the elimination of externally generated static or noise, or the correction of antenna problems or weak reception. This warranty does not cover labor costs or damage to the Product caused by installation or removal of the Product. Definitive Technology makes no warranty with respect to its products purchased from dealers or outlets other than Definitive Technology Authorized Dealer.

THE WARRANTY IS AUTOMATICALLY VOID IF:

1) The product has been damaged, altered in any way, mishandled during transportation, or tampered with.
2) The product is damaged due to accident, fire, flood, unreasonable use, misuse, abuse, customer applied cleaners, failure to observe manufacturers warnings, neglect or related events.
3) Repair or modification of the Product has not been made or authorized by Definitive Technology.
4) The product has been improperly installed or used.

This product complies with the essential requirements of the EMC directive 89/336/EEC.

Product must be returned (insured and prepaid), together with the original dated proof of purchase to the Authorized Dealer from whom the Product was purchased, or to the nearest Definitive factory service center. Product must be shipped in the original shipping container or its equivalent. Definitive is not responsible or liable for loss or damage to Product in transit.

THIS LIMITED WARRANTY IS THE ONLY EXPRESS WARRANTY THAT APPLIES TO YOUR PRODUCT. DEFINITIVE NEITHER ASSUMES NOR AUTHORIZES ANY PERSON OR ENTITY TO ASSUME FOR IT ANY OTHER OBLIGATION OR LIABILITY IN CONNECTION WITH YOUR PRODUCT OR THIS WARRANTY. ALL OTIER WARRANTIES, INCLUDING BUT NOT LIMITED TO EXPRESS, IMPLIED, WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, ARE EXPRESSLY EXCLUDED AND DISCLAIMED TO THE MAXIMUM EXTENT ALLOWED BY LAW. ALL IMPLIED WARRANTIES ON PRODUCT ARE LIMITED TO THE DURATION OF THIS EXPRESSED WARRANTY. DEFINITIVE HAS NO LIABILITY FOR ACTS OF THIRD PARTIES. DEFINITIVE'S LIABILITY, WHETHER BASED ON CONTRACT, TORT, STRICT LIABILITY, OR ANY OTHER THEORY, SHALL NOT EXCEED THE PURCHASE PRICE OF THE PRODUCT FOR WHICH A CLAIM HAS BEEN MADE. UNDER NO CIRCUMSTANCE WILL DEFINITIVE BEAR ANY LIABILITY FOR INCIDENTAL, CONSEQUENTIAL OR SPECIAL DAMAGES. THE CONSUMER AGREES AND CONSENTS THAT ALL DISPUTES BETWEEN THE CONSUMER AND DEFINITIVE SHALL BE RESOVED IN ACCORDANCE WITH CALIFORNIA LAWS IN SAN DIEGO COUNTY, CALIFORNIA. DEFINITIVE RESERVES THE RIGHT TO MODIFY THIS WARRANTY STATEMENT AT ANY TIME.

Some states do not allow the exclusion or limitation of consequential or incidental damages, or implied warranties, so the above limitations may not apply to you. This warranty gives you specific legal rights, and you may also have other rights which vary from state to state.

©2008 DEI Sales Co. All rights reserved.

EQAT020209

For more information on Definitive Technology Loudspeakers and accessories, visit www.definitivetech.com, or email [e-mail]. Definitive Technology, Owings Mills, Maryland, USA. 800-228-7148

Definitive Technology® The Leader in High-Performance Loudspeakers®