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Infinity Reference 475a

468W Reference Series Class AB 4-Channel Amplifier

Infinity
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• 75W x 4-Chan. @ 4 ohm
• 90W x 4-Chan. @ 2 ohm
• 117W x 4-Chan. Max
• MOSFET power supply
• Gold-plated preamp RCA outputs

Learn more about the 475a

Good news and a little bad...

This item has been discontinued

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Product Highlights


• 75W x 4-Chan. @ 4 ohm
• 90W x 4-Chan. @ 2 ohm
• 117W x 4-Chan. Max
• MOSFET power supply
• Gold-plated preamp RCA outputs

Description


Infinity brand icon

Authorized dealer

  • Reference Series Class AB 4-Channel Amplifier
  • RMS Power Rating:
    • 4 ohm: 75 watts x 4 chan.
    • 2 ohm: 90 watts x 4 chan.
    • Bridged, 4 ohm: 180 watts x 2 chan.
  • Max power output: 117 watts x 4 chan.
  • MOSFET power supply
  • LED power and protection indicators
  • Tuned Bass EQ (0-6 dB bass boost at 50 Hz)
  • IMS inputs allows connection to other Infinity expansion products
  • Gold-plated preamp RCA outputs
  • DC, overheat, over or under voltage, and short circuit amplifier protection
  • Gold-plated RCA level inputs
  • Variable high-pass filter (32-320 Hz, 12 dB/octave)
  • Variable low-pass filter (32-320 Hz, 12 dB/octave)
  • CEA-2006 compliant amplifier
  • Frequency response: 20-20000 Hz
  • Efficiency: 85 dB
  • Dimensions: 14-3/4"L x 9"W x 2-11/16H
  • 4-gauge power and ground leads recommended. Contact us for information regarding a discount on a select amplifier kit when purchased together.
  • Authorized Internet Dealer
  • 1 year Manufacturer's warranty

Product history:

Infinity REF704AAM thumbnail
(newest, current model)
Infinity Reference 704A thumbnail
(previous model, replaced by Infinity Reference 704A)
Infinity 475a thumbnail
(previous model, replaced by Infinity Reference 704A)
Infinity 7541A thumbnail
(previous model, replaced by Infinity Reference 475a)

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Specifications & Details


Power Specifications - Full Range Channels
RMS Power @ 4 ohms
75 watts x 4 channel
RMS Power @ 2 ohms
90 watts x 4 channel
RMS Power @ 1 ohm
Not Stable
Bridged RMS Power
180 watts x 2 channel
Amplifier Specifications
Series
Reference Series
Amplifier Class
A/B
Number of Channels
4-Channel
Total Peak Power Output
468 watts
Total RMS Power Output
360 watts
Maximum Input Gauge Size
4 AWG
Minimum Impedance Unbridged
2 ohm
Minimum Impedance Bridged
4 ohms
THD at Rated RMS Power
1%
Speaker Level Inputs
No
Preamp Outputs
1 pair
Built-in Crossover
Low-Pass (LP)
High-Pass (HP)
High-Pass Crossover Frequency
32 - 320 Hz
Low-Pass Crossover Frequency
32 - 320 Hz
Signal-to-Noise Ratio
85 dB
Bass Boost
0 - 6 dB
Remote bass/level controller
No
Fuse Rating
35A x 2 
Warranty and Return Policy
Parts Warranty Duration
1 year
Labor Warranty Duration
1 year
Warranty Provider
Manufacturer

Item Details


Manufacturer:

Model Number:

475a

Weight:

14.00lbs

Internal SKU:

475a

Internal Product ID:

9712

Product and How-to Videos


  • Harman International: The Pursuit of Great Sound
  • How To Install an Amplifier: Car Amplifier Basics Part 2

Customer Ratings & Reviews


Infinity Reference 475a thumbnail image

5 star
65%
4 star
20%
3 star
15%
2 star
0%
1 star
0%



Durability
4
Value
4.5
Features
4.5
Design
4.2
Usability
4.6

Customer Reviews

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Great Amp

I had this amp connected in my now wife's car in the trunk in Texas Heat.. and it was a great product, never went into protect. Look guys, this is a front stage and rear fill unit.. not really meant for Subs.. of course it's gonna overheat like that.

By JustM3 on July 23, 2011

26 found this helpful


Loud and Clear.

Got this thing hooked up nice to a pair of Component Alpine Type Xref's and a pair of Kenwood Execelon 172's. great clarity...hence Infinity. i only have it turned halfway up and its louder than any of my buddies systems. i can turn my head unit all the way up and its so clear and loud its disgusting. it makes everything sound perfect, and like your at the studio or concert. get it here. okay have fun get one right now cause this item is SICK.

By Derik on July 31, 2008

26 found this helpful


Great Quality Reliable Amp!!!

This is the second Infinity 475a I've purchased and installed, the first was almost 7 years ago and hasn't given me any trouble and it's been in two different trucks I've owned. It's always been pushing Infinity Reference or Kappa Speakers and has done a great job. So I bought another one to install in my little brothers truck and hopefully I will get the same results!!! The amp gets a little hot to the touch but that was to be expected having no active cooling. But the amp has NEVER shut off on me!!! It's got great simple adjustments and the build quality seems solid. Would highly recommend, it's a great amp for the money!!!

By Dalton on October 5, 2013

23 found this helpful


a bit dissapointed...

I bought this amp hoping to use it to push to 12's. It is a great amp for mids and highs, but not much else. The description should make this very clear, and it doesn't.

By joe bl on August 5, 2010

25 found this helpful


not what i expected

this thing over heats even with just speakers hooked to it.i have kappa 6.5 components in rear and front.sound quality is ok not great.very dissapointed.

By bobst on June 3, 2009

23 found this helpful


Great Value!

The amp are easy to plug and give a good sound ! Great product!

By Mathieu on December 26, 2012

22 found this helpful


Not Too Bad

Recently ordered this amp from Sonic. Shipping was fast and customer service was great. Finally got around to hooking it up and although I have not pushed it to hard as yet it sounds pretty good for an "entry level" amp. Signal to noise ratio isn't exactly the best as there is some hiss but so far it gives off pretty good power. Running it in tri way mode. Powering a set of components up front and a sub in the rear. Good enough for a daily system but not for a high sound quality build.

By Jason on September 5, 2011

22 found this helpful


Sounds Excellent!!

I have this amp pushing 4 Infinity Kappa 682.9cf, in my little 2 door truck. It sounds so loud in a little truck!! Excellent high's and mids! I don't know anybody with a better system! Also, have 2 10inch JL W3 subs to balance it out.

By Sonicelectronix=amazing on March 4, 2011

22 found this helpful


Best in its class

$30 off list price isn't one of the better deals on Sonic, but I think this amp is currently being phased out, so get it while it lasts. And it's CEA certified, so you know you're getting exactly what's on the spec sheet. At 75 watts RMS, it's enough to amp your music as loud as your ears can tolerate, and then louder. It's fairly easy to use with an intuitive design, and is definitely one of the sexiest looking amps out there (and the blue lights look awesome).

The biggest downside is the 1% distortion. But if you're thinking about buying this amp, you're probably relatively new to car audio and would not be able to tell the difference between 1% and .1%

The two stars for durability is because my friend bought one and two of the channels blew. So he returned it for another, and one of the channels blew again. He ended up getting fed up and going with Alpine. But when I inspected his system before the alpine install, I noticed a shoddy ground connection. I'm guessing that is why he blew the amps. But I have never had a problem with mine. It overheated ONCE last summer, because it was mounted vertically, in direct sunlight, and being played for 90 minutes on high volume.

Bottom line: if you install it properly, you will have no problems, and will love this amp. As far as "entry level" amps go, 5 stars!

By John on May 22, 2010

22 found this helpful


great product

I use this amp to power my four infinity speakers and one 300x1 infinity for a single sub and my car is loud and rockin, yet perfectly balanced.

By Scott on March 6, 2010

22 found this helpful




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