Boston acoustics CR55, CR75, CR85, CR65 User Manual

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CR55 CR65 CR75 CR85

Boston Compact Speakers

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CR75 CR85

Frequency Response (±3dB) 52–20,000Hz 48–20,000Hz

Recommended Ampliﬁer Power 15–100 watts 15–125 watts

Nominal Impedance 8 ohms 8 ohms

Sensitivity [1 watt (2.83v) at 1m] 89dB 90dB

Bass Unit 61⁄2

" (165mm) copolymer 7

" (180mm) DCD™ copolymer

Tweeter 1" (25mm) Kortec™ 1" (25mm) Kortec™

Crossover Frequency 2500Hz 2500Hz

Dimensions (HxWxD) 121⁄2 x 71⁄2 x 91⁄2" (318 x 191 x 241mm) 15 x 81⁄2 x 111⁄2" (381 x 216 x 292mm)

Weight 12 lbs (5.4kg) 163⁄4 lbs (7.6kg)

Speciﬁcations CR55 CR65

Frequency Response (±3dB) 80–20,000Hz 65–20,000Hz

Recommended Ampliﬁer Power 10–85 watts 15–100 watts

Nominal Impedance 8 ohms 8 ohms

Sensitivity [1 watt (2.83v) at 1m] 88dB 88dB

Bass Unit 4 1⁄2" (115mm) copolymer 5 1⁄4" (135mm) copolymer

Tweeter

⁄4" (20mm) dome

Crossover Frequency 4200Hz 4200Hz

Dimensions (HxWxD) 91⁄4 x 53⁄8 x 6" (235 x 143 x 152mm) 101⁄8 x 63⁄8 x 77⁄8" (257 x 162 x 200mm)

Weight 53⁄4 lbs (2.6kg) 9 lbs (4kg)

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Description

Continuing in the tradition of our critically acclaimed Compact Reference series, the second generation CR55, CR65, CR75 and CR85 are compact, versatile, high performance bookshelf speakers designed to deliver accurate, natural reproduction.

Special care has been taken to optimize the speakers’ components for maximum performance: The bass units utilize phase plugs that conduct heat away from the voice coil, thus increasing power handling and maximizing output. The woofer cones and surround geometry were designed and optimized with Boston’s Finite Element Analysis (FEA) computer modeling technology, for strong bass and smooth midrange.

High frequencies in the CR75 and CR85 are handled by Boston’s exclusive 1-inch (25mm) Kortec tweeter mounted in an innovative new wide dispersion projection tweeter baffle. This remarkable driver produces an extremely smooth, ﬂat response well beyond the audible range. An aluminum heatsink attached to the tweeter’s backplate dissipates heat quickly and efficiently, assuring cool, trouble-free operation—even at very high power levels.

All the drive units are designed at Boston’s Peabody, Massachusetts facility using state-of-the-art computer-design programs, and are built on Boston’s proprietary production lines to an incredible ±1dB—perhaps the industry’s tightest tolerance. The CR65, CR75 and CR85 feature MagnaGuard

magnetic shielding for safe placement near any sized

television set.

The drivers are positioned very closely to each other for smooth, uniform radiation in both the horizontal and vertical planes. Within the cabinets are specially tapered braces that lock the front and rear baffles together and provide strength and rigidity, thus minimizing cabinet resonances. The rear-mounted vent is smoothly ﬂared to reduce port turbulence, and all speakers feature ﬁve-way binding posts, allowing wiring with virtually any cable.

Mounting options include placement on stands and shelves via the included rubber feet, ﬂat attachment to walls with the built-in keyhole bracket and angled, offset mounting to walls via the optional CRB bracket. The logo plate can be easily rotated in 90° increments to maintain the speaker’s appearance when placing it on its side.

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How to Connect Your Speakers

Correctly wiring your speakers is important for achieving the best sound quality. Wiring should take just a few minutes, but it’s important to do it carefully, since incorrect wiring (such as reversed connections) can result in a poor soundstage and poor bass.

We recommend 18-gauge wire or thicker for runs up to 25 feet (8m), and 16-gauge wire or thicker for longer runs. Separate the ﬁrst few inches of the wire conductors. Strip off

⁄2" (12mm) of insulation from the ends of each speak-

er wire to expose the two conductors and tightly twist the wire strands.

WARNING: To prevent electrical shock hazard, always switch off the ampliﬁer or receiver when making connections to the speaker.

When making all connections, be sure to connect the + (red) on the speaker to the + (red) on the ampliﬁer, and the

– (black) on the speaker to the – (black) on the ampliﬁer.

IMPORTANT: Typically, one side of the wire is smooth.

Connect this side to the – (black) connection. The other side has a rib or stripe. Connect this to the

+ (red) connection.

Using the ﬁve-way binding posts: The binding posts

permit easy connection to banana plugs, spade lugs, and bare wire.

Insert the wire in the hole and tighten.

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STAND OR SHELF: Peel off the included rubber feet from their adhesive backing and stick them on to the four bottom corners of each speaker.

KEYHOLE BRACKET: Consult a knowledgeable installer regarding the proper hardware to use on your wall surface. A 1-inch (25mm) long wall anchor is recommended for hollow walls. Regardless of the type of wall fastener used, the screw head diameter should be between

⁄16 and 3⁄8-inch (8 to 9.5 mm) to ﬁt

properly inside the keyhole and slide down on to the slot. When wall mounting your speakers with the keyhole bracket, apply the rubber feet to the four stand off pads on the rear of the speaker to prevent any scratching or marring of the wall surface.

CRB BRACKET: This optional stand-off/swivel bracket can be purchased from your dealer or ordered directly from Boston Acoustics using the included order form. The CRB attaches to the back of the speaker using the four mounting holes located at either side of the keyhole bracket. Instructions on how to attach this bracket to the speaker and mount the assembly to the wall are supplied in the CRB kit.

Stand off pads (4)

Keyhole bracket

CRB mounting holes (4)

⁄8‘’(9.5mm) hole

Basic Hookup

1. Connect the speaker terminals to the ampliﬁer speaker outputs.

2. When making all connections, be sure to connect + to + (red) and – to – (black).

Mounting Options

Your CR speakers have several convenient mounting options:

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Connecting the CR Speaker to Your Ampliﬁer or Receiver

Checking the Speaker Connections

It is important that your speakers are hooked up with similar polarity or “in phase.” A simple listening test will tell you if your speakers are connected properly. Place the speakers face to face, as closely together as possible. While listening to music with your ampliﬁer set to MONO, reverse the connections at one speaker only. You’ll hear a dramatic change in sound. The connection that yields the fuller bass and louder sound is correct.

How to Place Your Speakers

Most people like to hear a realistic soundstage, as they would from a good seat in a concert hall. To achieve this effect, place the speakers 6 to 12 feet (2–4m) apart, so they form a triangle with your favorite listening position. The speakers should be at least 2 feet (0.6m) from the corners of the room. Putting the speakers too close to a corner can produce an unnatural bass reinforcement that detracts from their balanced, uncolored sound. If a speaker must be placed near a corner, move it away from the wall directly behind it to preserve its natural tonal balance.

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1. Remove the grille by gently pulling on the back of the top lip where it meets the front baffle. There are four pegs on the back of the grille that will pop out of their respective sockets which are located in the baffle plate.

2. Turn the grille over and locate the two light gray plastic spring tabs at the bottom center of the grille.

3. Depress the tabs with the tips of your thumb and ﬁnger until they are ﬂush with the round surface of the surrounding boss. You should hear a slight “click”, indicating that the tabs are now unlocked.

4. Turn the grille over and rotate the logo plate 90° in either direction to orient it to your desired position. Press the logo plate down until you hear the same “click” sound, thus locking it in place.

NOTE: Although it is possible to rotate the logo plate in increments other than 90°, it will not lock into position unless it is set to one of the four 90° locations.

• Depress spring tabs down with thumb to release lock

• Rotate logo plate 90°

• Note position of tabs in relation to logo orientation

Spring tabs on back of grille

Logo plate on front of grille

Logo Rotation and Grille Removal

The logo plates on your CR speakers can be easily rotated in 90° increments to maintain the speaker’s appearance when positioned on their sides.

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300 Jubilee Drive

Peabod y,

MA 01960 U.S.A.

978.538.5000 www.bostonacoustics.com

Kortec and DCD are trademarks and MagnaGuard, Boston, and

042-001287-2

Limited Warranty

For ﬁve years from the date of purchase, Boston Acoustics will repair for the original owner any defect in materials or workmanship that occurs in normal use of the speakers, without charge for parts and labor.

Your responsibilities are to use the system according to the instructions supplied, to provide safe and secure transportation to an authorized Boston Acoustics service representative, and to present proof of purchase in the form of your sales slip when requesting service.

Excluded from this warranty is damage that results from abuse, misuse, accidents, shipping, or repairs or modiﬁcations by anyone other than an authorized Boston Acoustics service representative.

This warranty is void if the serial number has been removed or defaced.

This warranty gives you speciﬁc legal rights, and you may also have other rights which vary from state to state.

If Service Seems Necessary

First, contact the dealer from whom you purchased the speakers. If that is not possible, write to:

Boston Acoustics, Inc. 300 Jubilee Drive Peabody, MA 01960 U.S.A.

We will promptly advise you of what action to take. If it is necessary to return your speaker to the factory, please ship it prepaid. After it has been repaired, we will return it freight prepaid in the U.S.A. and Canada.