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Our take on the JVC KD-R840BT by Crutchfield's Ken Nail
For great looks and great sound
JVC's KD-R840BT CD receiver ups the ante with its 5-zone Functional Variable Color faceplate. You can adjust any of the five distinct zones on the face to your liking, for a custom look that'll match your car's interior or your sense of style. And you can even have selected zones change color with your volume adjustments.
The sound measures up to the sharp styling, with a strong internal amp and a 3-band parametric equalizer, plus high- and low-pass filters to tailor sound output to your speakers. If you're looking to build a system with external amps, three sets of high-voltage preamp outputs ensure the cleanest performance from your system. Front and rear USB inputs give you more flexibility for connecting USB devices.
The 5-zone variable color display gives you plenty of customization options.
Bluetooth® equipped for safety and convenience
Bluetooth is great for talking hands-free, but that's not the only way it can enhance your car audio experience. Pair up JVC's KD-R840BT CD receiver with your smartphone, and enjoy audio streaming of Internet radio for more musical variety. And, with many Android™ phones, you can receive text message notifications too.
And here's a cool feature — let's say you've got a business phone and a personal phone. Most car stereos with Bluetooth make you choose one for use in the car, but the KD-R840BT lets you pair two phones at once. And when a call comes in, the receiver will blink either blue or red, depending on the phone. So you'll either have your business game face on, or be ready to relax and unwind when chatting with a friend.
Android™ smartphone compatibility
JVC's Smart Music Control works with Android phones to support voice commands for controlling your music. You'll be able to change songs, search your music, and more without raising a finger. But if you like to get your digits involved, you can create playlists with the Mood Blender, or even adjust EQ settings with your phone. And this app lets you use your compatible Android phone's touchscreen to control many functions using finger swipes and gestures — for example, tap the screen to play and pause, or swipe right to skip forward a track. So pop your Android phone in a mount, and you can reach down and skip a track without taking your eyes off the road.
Internet radio control
PANDORA® Internet Radio is one of the most popular streaming stations on the web. iPhone users can control PANDORA through this JVC when connected to the USB slot, while Android and Blackberry owners control Pandora through the Bluetooth connection. Either way, you'll enjoy access to your favorite stations and display of song, artist, and album information on the receiver's screen while you're listening.
Never miss your favorite radio programs
Do you have news, sports, or other radio programs you don't want to miss? The KD-R840BT's radio timer feature automatically switches on the radio and tunes in the correct station, no matter what source you're on at the time. You can set the timer to work one time or daily, so it's great for catching the shows you enjoy during your daily commute.
Want to keep your steering wheel controls?
In most vehicles, you can use an adapter (not included) to connect your vehicle's steering wheel controls to this JVC stereo. Connect a few wires, then program the adapter for your particular car and the receiver, and you'll retain the convenience of your steering wheel controls. Check the "Accessories" tab for compatible adapters.
Bluetooth note: Use of this receiver's Bluetooth features will depend upon your phone's Bluetooth capabilities. Learn more in our article explaining Bluetooth profiles.
iPod note: If you're going to use your iPod with this receiver, be sure to check "Details" for specific iPod model compatibility with this receiver or its optional iPod adapter.
Great product, sounds and looks good. Love the Bluetooth feature!
that one guy, Kansas
What's in the Box:
- CD receiver (with 10-amp ATC fuse inserted into chassis)
- Face (attached)
- Sleeve (installed)
- Trim ring (installed)
- Wiring harness
- Microphone with integrated bracket (attached 12' cable terminated by a right-angle male 3.5mm connector)
- Wireless remote control (RM-RK52)
- CR2025 3V Lithium battery (installed)
- 2 Radio removal tools
- Face fixing screw
- Face case
- Instruction Manual (En/Fr/Sp)
- US Warranty Sheet
- Canadian Warranty Card
- "Caution!" note (attached to wiring harness)
- Face Fixing screw note
- CD receiver with AM/FM tuner
- built-in MOSFET amplifier (20 watts RMS CEA-2006/50 peak x 4 channels)
- plays CDs, CD-Rs, and CD-RW discs including discs loaded with MP3, WMA, and WAV files
- Bluetooth for hands-free calling and audio streaming — full-time connection to two phones at once
- built-in iPod control and USB connection to Android phones
- control PANDORA® from your iPhone, Android, or Blackberry smartphone
- detachable face with 5-zone variable-color illumination
- remote control
- 24-bit digital-to-analog converter
- high- and low-pass filters
- 3-band parametric equalizer
- compatible with Sirius XM satellite radio tuner
- built-in iPod control and USB connection to Android phones
- inputs: front and rear USB inputs, front auxiliary input
- outputs: 6-channel preamp outputs (4.8-volt front, rear, and subwoofer)
Other features and specs:
JVC KD-R840BT Reviews
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Features and Specs
|Memory Card Slot||USB memory|
|Satellite Radio Ready||SiriusXM|
|RMS Power Output||20 watts|
|Peak Output||50 watts|
|RMS Power Bandwidth||20-20kHz|
|Sub Preamp Outputs||Yes|
|Switchable Rear Preamp Outputs||No|
|Preamp Voltage||4.8 volts|
|Key Button Color||Variable|
|Steering Wheel Control Compatible||Adapter required|
|Parts Warranty||1 Year|
|Labor Warranty||1 Year|
|FM Sensitivity||9.3 dBf|
|Radio Data System||Yes|
Bluetooth Technology: The JVC KD-R840BT is equipped with built-in Bluetooth (version 2.1+EDR), allowing you to make and receive phone calls wirelessly through the receiver; as well as stream music wirelessly from your smartphone to the head unit. In order to use Bluetooth wireless technology, your phone must also be Bluetooth compatible and be able to interpret certain profiles. This unit is compatible with the following Bluetooth Profiles:
- Hands-Free Communication: HFP 1.5 (Hands Free Profile), OPP 1.1 (Object Push Profile), PBAB 1.0 (Phone Book Access Profile).
- Audio Streaming: A2DP 1.2 (Advanced Audio Distribution Profile), AVRCP 1.3 (Audio/Video Remote Control Profile).
Note: Due to the differences in Bluetooth technology, some Bluetooth enabled devices may be incompatible, function improperly, or may not support all features when used with the JVC KD-R840BT. See JVC's Bluetooth compatibility chart for a complete list of compatible Bluetooth enabled devices.
Pairing: Your Bluetooth enabled mobile phone or digital audio player must be paired with KD-R840BT before hands-free & wireless operation. You can register up to five Bluetooth enabled devices with the JVC head unit. You can keep two phones connected at all times (only one can be used during a call).
Bluetooth Hands-Free Communication: The head unit supports Bluetooth hands-free communication for your Bluetooth enabled mobile phone. The controls of the KD-R840BT can be used to dial a number, answer an in-coming call, or end a call. The unit also includes an external microphone (with mounting bracket) featuring adjustable gain, so you can carry on your side of the conversation while listening to the caller through your vehicles speakers.
- Answering A Call: When a call comes in, a ring-tone will be heard through your vehicle's speaker and the caller's name or phone number will be displayed. You can also set the head unit's LCD to change colors when a phone call is received. You can answer the call from the head unit's front-panel controls, or setup the head unit to automatically answer the incoming call immediately or after 3/5/10 seconds. The KD-R840BT also supports the Call Waiting function, so you can answer another incoming call while suspending the current call you are on. Your compatible cell-phone must also support this feature.
- Dialing A Number: Using the KD-R840BT, you can dial a
phone number in one of the following ways:
- Entering a Phone Number: Allows you to directly dial a phone number up to 32 digits from the head unit's front-panel rotary dial.
- Speed Dialing: You can store up to 6 contacts in the memory of this unit for speed dialing.
- Phone Book: You can dial by using the downloaded phone book. You can download phone book data from your cell phone to the KD-R840BT.You can search through your contacts alphabetically (A-Z) or numerically (0-9). Up to 400 numbers can be stored for each registered cell phone.
- Call Log: The Call Log is a list of calls that have originated from and were received by this unit that you can dial. You can select Outgoing, Incoming, or Missed calls (up to 50 each).
- Voice Dialing: If your mobile phone supports voice recognition, then you can dial out by voice command. Simply speak into the included microphone.
Note: During a conversation, you can switch between the Private Mode (talking directly on your cell phone) and the Hands Free Mode.
External Microphone: The JVC KD-R840BT includes an external microphone to carry on your side of your phone conversation and voice command dialing. The external wired microphone offers improved audio quality versus an integrated microphone, so you can be heard easier over noisy traffic and road noise. You can adjust the volume level and noise cancellation of the microphone without affecting the other sources. The external microphone features an attached 12' cable terminated by a right-angle 3.5mm connector which plugs into the mic input on the rear-panel of the head unit. The microphone offers an integrated mounting bracket which can be clipped to your vehicle's sun-visor or taped to your dash. The external microphone measures 0.525" (diameter) x 1.485" (depth).
Note: This unit does not offer an integrated front-panel microphone.
SMS: If your Bluetooth enabled mobile phone is compatible with SMS (Short Message Service), the JVC head unit will notify you when a message has been received. You must then use your phone to check the message. You cannot read, edit, or send a message through this unit.
Wireless Audio Streaming (w/ Metadata Display): The JVC KD-R840BT also supports wireless audio playback (AD2P) and control (AVRCP) of a Bluetooth enabled audio player or smartphone. The KD-R840BT will be able to control basic playback functions of your Bluetooth device's stored music; such as Play/Pause, Skip Next/Previous, Fast Forward/Rewind and Random/Repeat. The head unit will also display your stored music's song information; such as Artist name and Song/Album title. The KD-R840BT also supports audio streaming of music apps downloaded on your smartphone with metadata display and limited control. Advanced music control of your music apps will still need be done via your Bluetooth-enabled smartphone. When an incoming call or outgoing call is in progress from your Bluetooth enabled mobile phone, audio streaming will be paused so you can take your call. Once the call is finished, your streaming music will resume.
Siri Digital Assistant Control: When paired and connected with an iPhone 4S or 5/5C/5S via Bluetooth (not USB), the JVC KD-R840BT has the ability to access Siri through its front-panel control and external microphone. Simply press the "phone command" button on theKD-R840BT to engage Siri and use the included microphone to communicate with Siri. Siri's voice will heard through your vehicle's speakers. All Siri functions including hands-free calling, music search, setting reminders, text-messaging, audible navigation, and more can be done through the head unit and its microphone. The head unit will only display hands-free calling and Bluetooth audio information (all other functions of Siri are only audible through the KD-R840BT; visual data will still need to be viewed from your iPhone device).
Note: You can ask Siri to get directions to a destination and the turn-by-turn instructions will heard through your vehicle's speakers, while the on-screen map still displays on your iPhone 4S/5/5C/5S. The head unit's audio is attenuated while Siri provides audible directions.
Disc Compatibility: The unit features a single disc player that will playback CD-Audio, CD-Text, and finalized CD-R/CD-RW audio discs. The unit also supports playback of MP3/WMA music files loaded onto CD-R/RW discs.
Dual USB Ports: The JVC KD-R840BT features a front-panel USB 2.0 type-A port (behind a sliding cover) and rear-panel USB 2.0 type-A port (attached to rear chassis by a 38" cable) for connection and control of a portable USB mass-storage class (MSC) device; such as select Android smartphones (Froyo/Gingerbread OS only), portable digital audio players, or USB thumbdrives. The USB ports enable audio playback and control of MP3, WMA, & WAV audio files stored on portable USB mass-storage class devices. USB portable audio devices that can be charged via USB will be charged when plugged into the CD receiver's USB ports (5V/1A), and the vehicle's ignition switch is set to ACC or On. You cannot connect a USB device via a USB hub or Multi-Card Reader to this unit.
MP3/WMA/WAV Playback: The JVC KD-R840BT supports the following types of MP3, WMA, & WAV files recorded onto CD-R/RW disc or loaded onto a USB mass storage class device.
|Media Type||CD-R/RW||USB Storage Device|
|File System||ISO9660 Level 1 or 2, Romeo, Joliet, or Windows long file name||FAT 12/16/32|
|Playable File Types||
MP3: bit rate of
8-320kbps w/ sampling rate of 8, 11.025, 12, 16, 22.05, 24, 32, 44.1,
|Maximum # of Folders/Files||255 folders/65,025 files (255 files per folder)|
|Tags||ID3 tag (version 1.0/1.1/2.2/2.3/2.4), WMA tag|
Track/Folder List: The Track/Folder List displays a list of MP3/WMA folders and tracks on a loaded CD or USB device, so you can easily access your music. The Track/Folder List will also display the list of track titles on a CD Text disc.
Character Search: You can search for your MP3/WMA/WAV music tracks alphabetically (A-Z) or numerically (0-9).
Random/Repeat Modes: The JVC KD-R840BT offers the following Repeat and Random playback modes.
- Repeat: Track Repeat (plays the current track repeatedly), Folder Repeat (plays all tracks of the current folder repeatedly), Off (cancels repeat function)
- Random: Folder Random (plays all tracks of the current folder, then the tracks of the next folder in random), All Random (plays all tracks of the current disc at random), Off (cancels random function)
Resume: If you change the source, playback also stops (without ejecting the disc or USB device). Next time you select CD or USB for the playback source, the player will start from where it has been stopped previously.
JVC Playlist Creator Compatible: JVC Playlist Creator is a free Windows-based desktop software that helps organize, manage and transfer MP3/WMA music files to your USB (MSC) device from your PC. When you playback audio files that have been stored on your USB (MSC) device using JVC Playlist Creator through the KD-R840BT, you can search a file by song title, album name, artist name, or genre using the head unit's Quick Search function. The JVC Playlist Creator is a Windows-based software that can be downloaded for free from JVC's website to your PC. The JVC Playlist Creator is compatible with the following Windows Microsoft Operating Systems.
- Windows XP Professional, Home Edition SP2 or later (32-bit)
- Windows Vista (32/64-bit)
- Windows 7 (32/64-bit)
Note: Not compatible with Apple iPod/iPhone/iPad, Zune, or Android.
Off Insert/Eject: A CD disc can be inserted or ejected with the power off. When a disc is inserted with the power off, the unit will automatically power up and begin playback.
Disc Protection: If the ejected disc is not removed within 15 seconds, the disc is automatically inserted again into the loading slot to protect it from dust. The source will change to CD, and the disc will begin playback, even if you have another source selected at the time.
Mounting: For proper disc playback you must install the unit within 30-degrees of horizontal.
iPod/iPhone Direct: The JVC KD-R840BT's front-panel or rear-panel USB port can acts as an iPod/iPhone high-speed direct connection when used with the USB/iPod cable that came with your iPod/iPhone. This USB connection allows audio playback, music navigation, information display, and charging of select iPod/iPhone models from the JVC in-dash head unit. The head unit supports audio playback from music stored on your iPod/iPhone or music apps (such as iHeartRadio, SiriusXM, Last.fm, Rhapsody, & Slacker) streamed to your iPhone (not all music apps will be compatible).
- DAC Bypass: The USB connection allows your iPod/iPhone's stored music and music apps to be loaded instantly to the head unit and sound quality to be maximized through the head unit's 24-bit D/A converter, allowing for a Signal to Noise ratio up to 105dB. The JVC head unit supports audio playback of music, podcasts, audiobooks, and music apps stored on your iPod or iPhone.
- Music Control: You can choose to operate your
iPod/iPhone through the JVC head unit's front-panel controls, from its
clickwheel/touchscreen, or via a streamed app from your iPhone.
- Head Unit Mode: From the head unit's front-panel controls you can search for music by Playlist, Artist, Album, Song, Podcast, Genre, and Composer. You can search a Playlist or Category alphabetically (A-Z) or numerically (0-9). The KD-R840BT also supports Repeat (file/all) and Random (album/all) playback functions of your iPod/iPhone. Your iPod/iPhone's clickwheel or touchscreen remains accessible in this mode. You can also control basic playback functions (such as Play/Pause, Previous/Next Track) from select music apps streamed to your iPhone.
- iPod Mode: You can choose to navigate your iPod or iPhone's stored music from its clickwheel or touchscreen, like you are accustomed to during normal usage. Basic playback control (such as Play/Pause, Previous/Next Track) can still be done through head unit for stored music and music apps.
- External Mode: External Mode allows you to solely navigate your connected iPod/iPhone device through its clickwheel or touchscreen. Playback of your iPod/iPhone's stored music and streamed music apps is supported. The head unit's iPod/iPhone controls will be locked.
- iPod Display: The KD-R840BT will display your Apple device's stored music and streamed music app song/artist information, when in Head Unit and iPod mode (not in External mode), or listening to Pandora Internet Radio. The head unit can display Track number, Elapsed playing time, Artist name, Song/Artist title, and Station identification
- iPod Charging: The head unit's USB connection provides 1A of current to power and charge your connected iPod/iPhone when your vehicle's ignition switch is set to the 'ACC' or 'On' position. This unit does not charge the iPad. If your iPod/iPhone has no initial battery charge, then the unit will not recognize it.
iPod Compatibility Chart: The JVC KD-R840BT is "Made for iPod/iPhone" compatible and supports the following iPod/iPhone model features (as of 9/13/2013):
|Apple Device||Generation||Tested Version||Media Type||Control Type||Display Type||Bluetooth||Charge|
|Audio||Video||Head Unit||iPod/iPhone||External mode||Pandora app||Artist/Song Text||Track Info||Phone||Audio||Siri|
Note: Apple iPod/iPhone software updates may change functionality results. If you download a newer software version, you may need to reset the head unit and your iPod/iPhone to regain functionality. If this doesn't work, you may need to wait until a newer software update is available.
JVC Music Control (for Android): By connecting the JVC CD receiver via USB to an Android smartphone (OS 2.2+) that has the free JVC Music Control app installed, it allows you to list and search all of the songs stored inside the smartphone from the receiver by artist name or album name. The JVC Smart Music Control app also analyzes all of your songs that are in your Android smartphone, and creates a playlist according to your mood. Once the application has completed the analysis of the songs, simply move the on-screen "mood ball" to your current mood, and this application will generate a list of songs that most fits your mood. Your compatible Android smartphone must be recognized as a USB mass storage class device; not compatible with MTP protocol.
Drive Change Mode (for BlackBerry): The receiver's USB port also supports playback from BlackBerry smartphones (via USB mass storage mode). JVC's Drive Change Mode lets you connect your BlackBerry smartphone (that uses an external memory card) directly to the head unit, via USB. Drive Change Mode will let you switch between your BlackBerry smartphone's internal and external memory (such as microSD Card), so you can listen to music stored on either memory. You'll continue to be able control basic playback functions; such as folder/file search, play/pause, and skip next/previous; regardless of memory type.
Front-Panel Auxiliary Input: A front-panel stereo minijack is provided to allow the connection of almost any portable audio source with a 3.5mm headphone output (great for those non-Apple/Android devices. Simply connect your portable digital music player to the unit's front-panel auxiliary input, and you can listen to the audio from the portable player through the speakers in your mobile audio system. The unit's front-panel auxiliary input can be turned On or Off.
RDS AM/FM Tuner: The JVC KD-R840BT features a built-in RDS AM/FM tuner with manual, seek, and preset tuning. The Radio Data System (RDS) feature displays radio broadcast information such as artist, title, and album when listening to compatible AM/FM stations. You can store a total of 18 FM stations presets and 6 AM station presets (manually or automatically). The head unit's Radio Timer features lets you tune into a preset station at a specific time regardless of the head unit's current source (you can activate the Radio Timer once, daily, or turn it completely off). If an analog FM stereo broadcast is hard to receive, you can manually switch the tuner to Mono operation. You can also switch the tuner's IF filter to Wide or Auto to increase/decrease the sensitivity.
Note: You can set the built-in AM/FM tuner between US standard and European tuning spacing.
Pandora Internet Radio: Pandora is the leading Internet Radio music service in the United States, giving people music they love anytime, anywhere, through personalized radio stations. The JVC KD-R840BT CD receiver lets you playback and control the Pandora Internet Radio music service that is being streamed to your Apple iPhone or Android smartphone. Your iPhone or Android smartphone will need an active Data Plan account with connection to the Internet via 3G, EDGE, or WiFi. In addition, you will need an active Pandora music service account.
- Smartphone Connectivity: The JVC KD-R840BT
supports playback of the Pandora app via your USB-connected iPhone or
Bluetooth-paired Android smartphone.
- Pandora App for iPhone: The KD-R840BT provides complete access to your Pandora account using your iPhone, via the head unit's front- or rear-panel USB port. To access Pandora you must have an Apple iPhone (iOS5 or later) with the latest version of the Pandora App from Apple's iTunes App Store.
- Pandora via Android: The JVC KD-R840BT lets you playback and control Pandora Internet Radio streamed from your Android smartphone, via Bluetooth (no hard-wired connection required). To access Pandora from the JVC head unit, your Bluetooth-enabled Android smartphone must have the latest version of the Pandora App from the Google Play App Store. Your Android smartphone must support A2DP, AVRCP, and SPP Bluetooth profiles.
- Pandora Control: The JVC KD-R840BT will provide control
over the Pandora music service streamed to your USB-connected iPhone or
Bluetooth-enabled Android smartphone.
- Station List: You can select Pandora stations from your Station List by date or alphabetically (A-Z).
- Create New Station: New stations can be created based on the current songs or artists playing on Pandora.
- Skip Songs: You can skip song tracks within a station. You cannot skip back to a previous song. Pandora limits the number of skips allowed.
- Thumbs Up/Down: You can give songs a thumbs up or thumbs down to help Pandora personalize stations to suit your preferences.
- Bookmarking: The song or artist currently being played can be bookmarked & stored in your Pandora account.
- Information Display: The JVC KD-R840BT will display Artist, Album, & Song information provided by the Pandora app on your iPhone or Android smartphone.
Note: Access to the Pandora service will depend on the availability of a cellular and/or WiFi network for purposes of allowing your iPhone or smartphone to connect to the Internet. Pandora is not supported in Canada and only available in the United States.
SiriusXM Ready: The JVC KD-R840BT comes ready for SiriusXM programming with access to XM and Sirius Satellite Radio stations. Thanks to its proprietary SiriusXM Connect port, you can add the optional SXV200V1 SiriusXM Connect tuner and receive more than 150 channels of exclusive programming directly from SiriusXM, via the "SiriusXM All Access" package (subscription required). Visit SiriusXM.com for a complete list of subscription options and channel guide. Additional features of the SXV200 SiriusXM Connect tuner include:
- Channel list displays a list of all available channels
- Category Search searches for channels in a certain category
- Displayed Information such as Channel Name, Artist Name, & Song Title can be viewed on the head unit's LCD
- Up to 18 SiriusXM Satellite Radio station presets
- Direct Tuning via included remote
- Supports the SiriusXM Instant Replay function, so you can pause, rewind, and replay up to 30 minutes of live content
- Channels containing unsuitable content for children can be blocked
Note: A separate SiriusXM Satellite Radio subscription is required (operates on the XM Network). However, you can easily add this SiriusXM tuner to an existing Sirius or XM account for a Multi-Radio Discount Plan.
24 Bit D/A Converter: The JVC KD-R840BT utilizes a 24-bit digital to analog converter for superior sound quality.
MOSFET Amplifier: The KD-R840BT is equipped with a MOSFET amplifier. Compared to conventional power supplies, the MOSFET amplification circuit is smaller and more efficient, and it delivers increased power with less distortion and absolutely zero on/off switching noise. More power means louder and cleaner music at higher volumes because you're not pushing the limits of the amplification circuit.
CEA2006 Compliant: The power specifications for the KD-R840BT are compliant with the CEA2006 Mobile Amplifier Power Testing and Measurement standards from the Consumer Electronics Association (CEA). These standards were developed as a way to equitably compare power specs from model to model and between manufacturers. The power output specs for the KD-R840BT are as follows:
- CEA2006 Specs: 20 watts RMS x 4 channels (at 4 ohms, 20Hz-20kHz, 1% THD-N)
- Maximum Power Output: 50 watts x 4 channels (200 total watts)
Amplifier Gain Control: When you are using the KD-R840BT with factory speakers (or those rated to less than 50 watts peak), the Amplifier Gain Control can limit the amount of power being sent to those speakers. When the Amp Gain Control is set to "low," the volume control ranges from 0 (minimum) to 30 (maximum). When using speakers rated higher than 50 watts peak, you can set the Amp Gain Control to "high," and the volume control will range from 0 to 50.
6ch/4V Preamp Outputs: The KD-R840BT is equipped with 6ch/4.8V preamp outputs (Front, Rear, Subwoofer). The front and rear preamp outputs allow fader control, while the subwoofer preamp output is non-fading.
Subwoofer Controls: The head unit's sub preamp output features a low pass crossover and independent volume control. You can set the cutoff frequency of the low-pass filter at 55Hz, 85Hz, or 120Hz. You can adjust the head unit's subwoofer level between -8 and +8 (separate from the main volume level).
High-Pass Filter (for Front & Rear Speakers): You can activate a variable high-pass filter (100, 120, 150, Hz or Through) for the unit's front & rear channels (speaker- or preamp-level), so low frequency signals are cut off from your system's front & rear speakers.
Pro EQ: The KD-R840BT is equipped with JVC's Pro EQ. The integrated equalizer offers 7 preset sound modes (Flat, Natural, Dynamic, Vocal Boost, Bass Boost, & User) suitable for the music genre of your choice. The User mode allows you to manually adjust the head unit's 3-band parametric EQ (Frequency, Level, and Q-Factor).
|Bass||60, 80, 100, 200 Hz||+/- 12 dB (-6 to +6)||1.0, 1.25, 1.5, 2.0|
|Midrange||0.5, 1.0, 1.5, 2.5 kHz||+/- 12 dB (-6 to +6)||0.75, 1.0, 1.25|
|Treble||10.0, 12.5, 15.0, 17.5 kHz||+/- 12 dB (-6 to +6)||Fixed|
Note: You can store Pro EQ bass, middle and treble tone settings for each source (CD, AM/FM, Aux, USB, iPod, Bluetooth, and Pandora).
Bass Boost: The unit's Bass Boost enhances low bass frequencies.
Loud (Loudness): This feature boosts low and high frequencies to produce a well-balanced sound at a low volume level. You can set this feature to High, Low, or Off.
Volume Adjust: The input level of each source (other than FM) is adjustable relative to the FM radio volume, so there isn't a significant volume difference when changing sources. Each source is individually adjustable from -5 to +5.
Key Beep: The in-dash head unit provides an audible beep to confirm button operation. This function can be turned On or Off.
Detachable Face: The JVC KD-R840BT features a detachable face to deter theft (a hard plastic face case is provided). An optional soft face case (142DFC1X, sold separately) can also be purchased for this unit. A face-fixing screw is supplied for making the face non-detachable, if desired.
5 Zone Variable Color: The head unit's variable color illumination is separated into 5 Zones (LCD, rotary dial, button zone 1, button zone 2, and button zone 3). The KD-A845B offers 29 color presets and custom colors for each of these zones. You can choose one of these color presets or select the ColorFlow mode which scrolls through all 29 color presets. Additionally, there is a User preset, allowing you to individually adjust the intensity of Red, Green, and Blue from 0 to 31; resulting in approximately 30,000 custom color options. You can choose to use the same color for all 5 Zones, or use a different color for each separate Zone.
- LCD Zone: The LCD zone refers to the head unit's LCD screen.
- Rotary Dial Zone: The rotary dial zone refers to the unit's rotary volume control.
- Button Zone 1: Button Zone 1 contains Phone, Menu, Source/Power, Back/Return, Next/Previous Track buttons.
- Button Zone 2: Button Zone 2 contains EQ, Display, Preset 1, Preset 2, and Preset 3 buttons.
- Button Zone 3: Button Zone 3 contains Preset 4, Preset 5, Preset 6, and Eject buttons; along with USB port backlight.
Lighting Effects: You can select a preset color change pattern/speed for all zones (LCD, rotary dial, button zone 1/2/3). Choose from Spectrum, Groove, Techno, Emotion, Relax, and NightSweep.
5 Zone Brightness Control: The unit offers a daytime and nighttime brightness setting for the LCD, rotary dial, button zone 1, button zone 2, and button zone 3. You can also adjust the brightness level of each zone manually from 0-31.
Color Guide: When activated, the Color Guide mode changes the display and all button illumination to white when menu settings or music list search are performed.
Auto Illumination Dimmer: The display/button illumination dimmer can be set to Off (normal brightness at all times), On (display/button illumination is always dimmed), or Auto (display dims when 12-volts is applied to the orange/white illumination lead).
Wireless Remote Control: The KD-R840BT comes supplied with a wireless remote control (RM-RK52). The remote contains Attenuator, Sound, Source, Tracking, and Volume functions. The remote operates off of a single CR2025 3V Lithium-cell battery (included).
Steering Wheel Remote Compatibility: The head unit features an OEM steering wheel remote control input wire (blue/yellow) within the included wiring harness that lets you keep your vehicle's factory radio steering wheel remote controls when used with an optional steering wheel audio control adapter (sold separately). Please consult Crutchfield's Outfit My Car to see if your vehicle is compatible.
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4 questions already asked
1 answer The description says "Connects to two phones at once". What exactly is the benefit of this? What limitations are there? Can either phone play streaming audio or make a call? Which phone takes priority to make or receive a call? Can calls be made through the rear USB connection, and will it also charge? [ Colin Mar 21, 2014 ]
I forwarded your question to an Advisor and they responded with the following: If two phones are connected at the same time, whichever one is in use first would take priority over the other. For example if Phone A receives a phone call then Phone B will not be able to receive or make a phone call via Bluetooth. Same goes for the audio, if Phone B is playing Bluetooth Audio then Phone A would not be able to stream audio via Bluetooth. Unfortunately we no longer stock this radio, and I'm not sure if we have another model that will allow two phones to be connected at the same time. If you would like to discuss further you can contact an Advisor directly by phone (1-800-324-9695) or online chat. [ Krissy Mar 22, 2014 ] Staff
I have had no issues with radio reception with this unit however, I live in the Atlanta area so I do not go through any rural areas. When I was installing the unit, there was an extra wire on the antenna adapter but nothing anywhere said what that wire was or what it was for. I finally figured out that it was a power wire for the antenna. After I hooked that wire into the remote power wire in the back of the unit, I had no issues with reception. [ CASEY Feb 18, 2014 ]
Great sensitivity, I get my country stations all over my area and up into the hills here in northern cali! Hope this helps [ JAMES Feb 17, 2014 ]
You will get better sound quality when bypassing the factory amplifier. However, that will require you to run the wiring harness from the radio location to the amplifier location. Please contact an Advisor by phone or chat for more details on your installation. [ Jeff Nov 22, 2013 ] Staff
2 answers My previous blutooth head units from pioneer maintained their bluetooth connections when powered down, and would wake for an incoming call. Is this unit capable of this behavior? Mine is not doing this, and I am very disappointed. I do not want to have to keep the unit on at all times while driving just so I can receive a hands free call! [ Paul Nov 17, 2013 ]
I have a similar question before buying and that is about how easily the pairing happens. I am looking for instant/automatic pairing, Assuming my bluetooth is activated on my phone. [ Colin Mar 21, 2014 ]
If you purchased the receiver from Crutchfield, feel free to contact our Tech Support team. They can help check walk through the settings on the receiver and see if there may be a fix. [ Jeff Nov 18, 2013 ] Staff