Skip to main content
Chat
Photo of Expert Advisor Cam
Contact us

Expert help from our Advisors

What is an expert Advisor?
Connect ID #
985 902 205 5
Connect ID #
985 902 205 5
Don't wait on hold. We'll call you back when it's your turn to talk with the next available .
Please enter your name  
Please enter your phone number  
Please enter a message  

Calls may be recorded for training and quality control purposes.

We are located in Virginia USA.

Thank you. We will be calling you .
We're sorry. We have encountered a problem.

Infinity DSP6840 8-channel car amplifier with digital signal processing — 40 watts RMS x 8

Item # 108DSP6840

Pump up the power and fine-tune the sound.

Find what Fits your vehicle

Remove

Checking fit...

Pump up the power and fine-tune the sound.

Item # 108DSP6840

Ships free today

Every order includes

  • Free lifetime tech support
  • 60-day price-drop protection
  • 60-day returns
In stock
$484.95

Other options

Get questions answered fast & free

Expert help 400+ hours training Virginia-based

About the Infinity DSP6840

Buck Pomerantz

Product highlights:

  • 8-channel car amplifier with digital signal processing
    • 40 watts RMS x 8 at 4 ohms
    • 60 watts RMS x 8 at 2 ohms
    • non-bridgeable
  • Class D amp technology
    • frequency response: 10-22,000 Hz
Digital processing:
  • DSP and EQ tuning tool adjustments made via USB connection to a Windows PC
    • save up to 10 presets
  • 6 assignable preamp and speaker-level inputs
    • high-level input adapters included
  • 31-band EQ (selectable parametric and graphic)
  • adjustable high-, low-, and band-pass filters: 20-20,000 Hz
    • selectable filter slopes: 6, 12, 18, 24, 30, 36, 42, 48 dB/octave
  • adjustable delay: 0 to 12ms in 0.2ms increments
  • phase adjustment: 0/180°
Other Features:
  • includes wired remote bass control for ch 7 & 8
  • conformal coated PCB
  • fuse rating: 40A x 1
  • wiring and hardware not included with amplifier
    • 8-gauge power and ground leads recommended
  • dimensions: 5.67"W x 1.95"H x 9.35"D
  • warranty: 1 year
  • MFR # DSP6840AM
  • Item # 108DSP6840
  • California customers: Please click here for your Proposition 65 WARNING.

What's in the box:

Infinity DSP6840 owner's manual

If you need assistance accessing this owner's manual, please give us a call.
  • 8-Channel DSP amplifier with attached 6" RCA inputs
  • 8" Power/Speaker/Remote harness with in-line 40A ATO fuse
  • Spare 40A fuse
  • 8" Speaker output harness
  • Remote bass level control
  • 16.5' Remote level control cable (RJ-25 jacks on both ends)
  • 6 Speaker wire-to-RCA adapters
  • USB Stick with tuning software
  • 70" USB Cable (type-A both ends)
  • Four 5/8" Screws
  • Two 3/8" screws
  • 4 Flat-washers
  • 4 Split lock-washers
  • Four 5" Zip ties
  • Owner's manual (En/ Sp/ Fr/ Others)
  • Safety instructions

More details on the Infinity DSP6840

Mark G.

Product Research

Features

Overview: The Infinity DSP6840 amplifier/audio processor lets you fine-tune your vehicle's audio system, with an easy-to-use interface and numerous tuning capabilities. It features six input channels, accepting pre-amp or speaker level signals, that can be summed and assigned to any of the processor's eight powered output channels. Each channel has its own 31-band parametric or graphic EQ, high and low pass crossovers with selectable slopes, and time delay, all configured using your connected Windows PC.

Note: The amp does not include any wiring; an 8-gauge amp wiring kit is recommended (sold separately).

Inputs: The amp has six attached RCA jacks on 6" leads for use with aftermarket radio pre-amp outputs. The RCA inputs can also accept speaker-level signals from factory radios or aftermarket radios with no pre-amp outputs. Six speaker wire-to-RCA adapters are included for connecting high-level inputs. The software-based configuration lets you sum together channels from any of the inputs and assign them to any of the eight powered output channels. Input signals can range from 0.680 to 15 volts.

Outputs: The DSP amplifier features eight powered speaker outputs on a removable 8" harness. Each speaker output can provide the following power (@ 14.4V, <1% THD+N):

  • 2-Ohms: 60 W x 8
  • 4-Ohms: 40 W x 8

Note: The DSP6840 does not support bridging any of the output channels.

Remote Bass Level Control: A wired remote bass level control is included that lets you adjust the low-frequency output level of channels 7&8 from the driver's seat. The level control has an adjustment range of -30 to +6 dB, and includes a 16.5' attachment cord that plugs into the amp chassis.

DSP: Configuration of the DSP software is done using a Windows PC (MAC is not supported) connected to the amplifier/processor using the included USB cable. The tuning software is downloaded from Infinity's website. Configuration parameters can all be accessed from one main screen, and include the following options:

  • Speaker Locations: designate the type of speaker (woofer, midrange, tweeter, full range) and location (left, right, front, rear, center, sub) for each output channel; a graphic display shows each channel's location
  • Input Mixer: any of the six input channels can be assigned to any of the eight output channels; multiple input channels can be summed to the same output channel, allowing a full-range speaker to get its signal from separate tweeter and woofer signals in a factory system
  • Linking Channels: each pair of output channels (1/2, 3/4, 5/6, 7/8) can be linked together, so controls can be applied to both simultaneously
  • Channel Volume: each channel's output level is independently adjustable; -60 to +6 dB in ½ dB steps
  • Equalizer: each output channel has an independent 31-band graphic or parametric EQ; the parametric EQ lets you select each band's center frequency (20-20,000 Hz), adjust the Gain for that frequency (-15 dB to +10 dB), and set the Q or "width" of the selected frequency (0.5 to 9); the graphic EQ has 31 fixed frequencies, with only gain adjustment (-14.9 dB to +9.9 dB), frequencies are 20 Hz, 25 Hz, 31 Hz, 40 Hz, 50 Hz, 63 Hz, 80 Hz, 100 Hz, 125 Hz, 160 Hz, 200 Hz, 250 Hz, 315 Hz, 400 Hz, 500 Hz, 630 Hz, 800 Hz, 1 kHz, 1.2 kHz, 1.6 kHz, 2 kHz, 2.5 kHz, 3.1 kHz, 4 kHz, 5 kHz, 6.3 kHz, 8 kHz, 10 kHz, 12.5 kHz, 16 kHz, 20 kHz
  • Crossover: each channel has independent high-pass and low-pass filters; crossover points can be set to any frequency (20-20,000 Hz) and the slope can be 6, 12, 18, 24, 30, 36, 42, or 48 dB/octave (off bypasses the crossover)
  • Time Delay: the delay for each output channel is adjusted independently; the units are inches (0-163 in 1" steps), centimeters (0-415 in 1cm steps), or milliseconds (0-12 in 0.01ms steps); the result is all audio signals arriving at the desired focal point at the same time
  • Phase: the phase of each channel can be reversed to correct any inadvertent phase cancellation caused by vehicle acoustics (0°/180°)
  • Clipping Indicators: each channel has a clip indicator; lights if 10% or higher distortion is present
  • Presets: ten DSP configurations can be stored and recalled via one of the ten preset buttons

Input Level: A 2-positon switch on the end of the amp specifies the input signal level, Low for pre-amp level signals and High for speaker level signals.

Turn-On Mode: A 3- position switch determines how the amplifier is turned on:

  • REM: If pre-amp connections are used, the remote in wire in the harness is connected to the radio's remote output. A remote output is also provided for activating additional equipment.
  • DC: This mode activates the amp when it senses the ignition has been turned on.
  • Audio: Activates the amp when it detects an audio signal on the inputs.

Protection Circuit: A red LED will light if a problem is detected, including short-circuit on a speaker output, over/under voltage, excessive heat, or amp output circuit failure.

Power/Ground Wiring: The DSP6840 includes a removable 8" wiring harness with 10-gauge connections for Power (with in-line 40A ATO fuse) and Ground. The harness also includes 18-gauge wire connections for Remote In and Remote Out.

Note: The Infinity DSP6840 will require an 8 AWG amplifier wiring kit, which is sold separately.

Mounting: The DSP6840 has mounting tabs with 4 key-hole slots for attaching the amp to a flat surface. Mounting hardware is provided.

Specifications:

  • RMS Power Output:
    • 4-Ohms: 40 watts x 8
    • 2-Ohms: 60 watts x 8
  • Amplifier Class: D
  • Operating Voltage: 8-16 volts
  • Frequency Response: 10 Hz - 22 kHz (-3 dB)
  • Signal-to-Noise Ratio: >90 dB
  • Signal-to-Noise Ratio (CEA-2006): 75 dB
  • THD+N (@ 4-Ohms): <1%
  • Input Sensitivity:
    • Low Level: 680 mV - 6 V
    • High Level: 1.6 V - 15 V
  • Fuse Rating: 40-amp (ATO)
  • Recommended Power & Ground Wire: 8-gauge (not included)
  • Dimensions:
    • Width: 5.67"
    • Height: 1.95"
    • Depth: 9.35"
  • Weight: 2.2 lbs.

The Infinity DSP6840 replaces these items:


Adding...
Infinity DSP4425

Infinity DSP4425

4-channel car amplifier with digital signal processing — 25 watts RMS x 4
  • inputs: 4 assignable and summable
  • outputs: 4 powered and processed, 2 preamp (4V) full-range
  • time alignment, crossover filters, 31-band EQ, and more

Loading accessories...

Customer Q&A

1 question already asked

Q
I have a Infinity Primus installed. Two 753T, 40W rms each. Four 603F 50W rms each. I understand the dsp/amp is rated for 40w rms at 4ohms, how will this affect the set up with the 603F's? Thank you.
juan  Apr 04, 2025
1 answer
A
Greetings Juan. That is an excellent question. Resistance can be measured at the amp, and it can be measured at the speaker. At the speaker, Infinity and JBL for that matter measure out at 3 ohms. Speaker wire adds resistance too. so after the wire goes from the speakers to the amplifier, it will register 4 ohms. So the amp will be putting out the 40 watts. Safe to run your Primus speakers.
thomas  Apr 04, 2025 (Staff)

Loading articles...

Compare the sound