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Infinity Reference 475a

468W Max, Reference Series Class AB 4-Channel Amplifier (REF475A)

4.5

(17 reviews)

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Specials with this product

  • Free Ground Shipping to the 48 statesdetails
  • Reference Series Class AB 4-Channel Amplifier
  • RMS Power Rating:
    • 4 ohms: 75 watts x 4 chan.
    • 2 ohms: 90 watts x 4 chan.
    • Bridged, 4 ohms: 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
Power Specifications - Full Range Channels
RMS Power @ 4 ohms75 watts x 4 channels
RMS Power @ 2 ohms90 watts x 4 channels
RMS Power @ 1 ohmNot Stable
Bridged RMS Power180 watts x 2 channels
Peak Power Output117 watts x 4 channels
Amplifier Specifications
Amplifier ClassAB
Number of Channels4
Total Peak Power Output468 watts
Total RMS Power Output360 watts
Maximum Input Gauge Size4 AWG
Minimum Impedance Unbridged2 ohms
Minimum Impedance Bridged4 ohms
THD at Rated RMS Power1%
Speaker Level InputsNo
Preamp Outputs1 pair
Built-in CrossoverLow-pass (LP)
High-pass (HP)
High-Pass Crossover Frequency32 - 320 Hz
Low-Pass Crossover Frequency32 - 320 Hz
Subsonic FilterN/A
Signal-to-Noise Ratio85 dB
Channel SeparationN/A
Bass Boost0 - 6 dB
Bass/Gain RemoteNo
Fan CooledNo
Fuse Rating35A x 2 
CEA-2006 CompliantYes
Warranty and Return Policy
Return Policy Standard Return Policy
Parts Warranty Duration1 year
Labor Warranty Duration1 year
Warranty ProviderManufacturer
Customer Review Summary for Infinity Reference 475a
Average Customer Rating is 4.5 out of 5 stars:
4.5
based on 17 Reviews
Share your thoughts with others:
Rating Distribution:
5 star:
.
.
65%
4 star:
.
.
18%
3 star:
.
.
18%
2 star:
.
0%
1 star:
.
0%
what's this?
Average Attributes Rating:
Durability
3.9
Value
4.5
Features
4.4
Design
4.2
Usability
4.5
what's this?
Quick Comparison:
Most Helpful Customer Reviews:
September 5, 2011 Not Too Bad
Review by
Jason from Toronto, Canada
Overall
Durability
Value
Features
Design
Usability
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.
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July 23, 2011 Great Amp
Review by
JustM3 from Houston Tx
Overall
Durability
Value
Features
Design
Usability
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.
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March 4, 2011 Sounds Excellent!!
Review by
Sonicelectronix=amazing from Las Vegas, Nevada
Overall
Durability
Value
Features
Design
Usability
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.
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July 19, 2010 Awsome amp!
Review by
Heckler from Wa.
Overall
Durability
Value
Features
Design
Usability
This amp drives the heck out of my Infinity Kappa's. I have the amp turned down turned almost all the way down because it's too loud! Awesome!!!
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May 22, 2010 Best in its class
Review by
John from North Reading, MA
Overall
Durability
Value
Features
Design
Usability
$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!
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View All 17 Reviews for Infinity Reference 475a
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Main Product
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Infinity 475aInfinity Reference 475a$169.99

Product Summary

Manufacturer: Infinity
Model number: 475a
UPC: 050667034993
Weight: 14.00 lbs
Internal SKU: 475a
Internal product ID: 9712

Price Information

$279.95

–$109.96

$169.99

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Customer Testimonial

I'm a first time consumer with Sonicelectronix. The price of my product was way cheaper than going a car audio store or any other online site.
UPS ground delivered it on time. I will buy from here again!

- Capp from Winston-Salem.NC

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