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RetroSound Quad4

Compact add-on amplifier for RetroSound radios — 45 watts RMS x 4 channels

Item #: 068QUAD4

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3 Reviews | Ask Questions

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More power, Captain

You've got a classic car with a RetroSound radio installed, but you want more power for your front and rear speakers. Enter the RetroSound Quad4, an ultra-compact 4-channel amplifier rated at 45 watts RMS per channel, which offers plug-and-play hookup to any RetroSound radio. You can connect other aftermarket car stereos via the Quad4's low-level RCA inputs.

Big sound, small package

At roughly the size of a large candy bar, the tiny Quad4 delivers a mighty sound, while its dimensions allow mounting almost anywhere, including under seats and behind the dash. If you're using a sub in your classic ride, you can activate the built-in high-pass filters to remove the low bass from your full-range speakers so they play louder and cleaner. The Quad4 also features advanced thermal and short-circuit protection so you'll be able to enjoy your sound for years to come.

Product Highlights:

  • ultra-compact 4-channel amplifier
  • 45 watts RMS x 4 at 4 ohms
  • direct input/output connection to all RetroSound radios
  • RCA inputs available for non-RetroSound receivers
  • switchable high-pass filters (110 Hz, 12 dB/octave)
  • frequency response: 10-40,000 Hz
  • advanced thermal and short-circuit protection
  • fuse: 15A
  • 10-gauge power and ground leads recommended
  • dimensions: 7-3/16"W x 1-13/16"H x 2-15/16"D
  • warranty: 1 year
  • Our 60-day money-back guarantee

My system has plenty of power. Who needs an amp?

You might think you don't need an amp because you have a 400-watt system in your car, or because your new stereo puts out 50 watts a channel. But those are peak wattage ratings, which may boil down to 15 or 20 watts per channel, using the more realistic RMS rating. An amp sends your speakers the power they need to deliver your music with clarity and impact, whether you're using factory speakers or high-performance components. And low-frequency reproduction requires lots of power, so an amp is an absolute must if you're adding a sub to your system.

RetroSound Quad4 Reviews

Average Customer Review:

3 Reviews

Quad 4

Written by: Phil from Virginia on November 15, 2015

Crutchfield Customer Review (What's this?)

I has a Retrosound model 2. So this review is only relevant if you own a Retrosound. Pretty much a plug and play. Yellow power wire to + battery terminal. Black ground wire to nearby metal car frame. Other wires use retrosound model 2 wire connectors. The Quad 4 is small and easy to hide under the dash. Restrosound model 2 is not a great stereo when it comes to sound so I feel the addition of the Quad 4 is a must. Sounds is full and richer at all volumes. Also love the retro look this system gives my 59 Porsche 356 replica. Awesome.

Pros: Compact. Plug and play with Retrosound model 2. Full rich sound.

Cons: None.

RetroSound Quad4

Written by: Anonymous from Massachusetts on October 6, 2015

Crutchfield Customer Review (What's this?)

nice addition to the head unit. Makes all the difference in the sound quality .

Pros: EZ plug and play install

Cons: All good

Retrosound Quad4 amp

Written by: ScottM from Massachusetts on June 18, 2014

Crutchfield Customer Review (What's this?)

Nice little amp that goes well with retrosound stereo already installed in my ride

Pros: Simple add on installation to Retrosound stereo, simply remove speaker and control jacks from stereo and plug amplifier in its place, reconnect the jacks and add a power circuit and enjoy!

Cons: None to date.

Customer Q&A