Polk Audio Atrium Series (4, 5, 6, 8-SDI) Indoor-Outdoor Speakers Review

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Polk is one of the most well known audio manufacturers in the world, and the Atrium is their flagship series of traditional indoor-outdoor speakers. It was introduced circa ~2002, yet remains one of the best selling and highly user rated speaker series on the market. The product line currently has four models:

  • The Atrium 4
  • The Atrium 5
  • The Atrium 6
  • The Atrium 7 (discontinued)
  • The Atrium 8 SDI

Each unit varies slightly in baseline power specs and thus corresponding price. Also, the 8-SDI, short for single/dual input, is distinct in that it can function as a standalone speaker with both channel inputs or as part of a pair. But other than that they all have the same design, which is why we’ve decided to do an all inclusive series review in one page here.

The Atrium 4s in black, click to see zoomable image on Amazon (affiliate link)

Atrium Series Specs Comparison Table

ModelAtrium 4Atrium 5Atrium 6Atrium 8-SDI
Speaker Typepassive, wired(<-- same)(<-- same)(<-- same)
Nominal Power *26W33W33W33W x 2
Peak Power80W100W100W125W x 2
Impedance8 Ohms(<-- same)(<-- same)(<-- same)
Sensitivity89 dB/W/m90 dB/W/m90 dB/W/m91 dB/W/m
Frequency response range 75Hz - 25kHz 60Hz - 25kHz50Hz - 27kHz45Hz - 27kHz
Unit Weight3.6lbs4.6lbs5.4lbs9.7lbs
Unit Dimensions
(depth x width x height)
6.75 x 5.75 x 8.5 inches7.75 x 6.75 x 10.5 inches8.75 x 7.75 x 11.759.2 x 8.5 x 12.8
(does include Amazon.com purchase)
5 years(<-- same)(<-- same)(<-- same)
Product Manualclick here(<-- same)(<-- same)(<-- same)

Review and Discussion

With an (approximated) continuous power handling of around 25-35W any of these speaker sets is sufficient to fill a non-large enclosure. We’ve seen comparable competitors to each of these units boast higher power handling specs, but, the Atrium’s sensitivity rating of 89+ is quite good, which could easily make up the difference. Also, the Atrium 5 and up have a 60Hz or lower frequency response floor, ensuring a strong bass, which is particularly important with outdoor speakers because bass doesn’t carry as well in the open air. The budget-tier atrium 4s might be well suited to pair with a sub woofer into a 2.1 system to ensure sufficient bass.

Aesthetics is where Polk really shines, and we think these speakers look great. They come in a fairly boilerplate black or white variation, but, the Atrium speakers are, in our opinion at least, one of the best looking traditional wall-mount box speakers on the outdoor/all-weather market.

Size and weight wise these speakers are pretty middle of the road – they shouldn’t be too hard to place and set up. They all come with a standard swiveling C-bracket for mounting, with one distinction being the “speed-lock” feature, which makes it easier to fasten the speaker to the mount once it’s bolted in.

Atrium speakers also excel is the utility of design and durability. They “exceed baseline industrial and military specifications for environmental endurance,” which includes even the harshest conditions such as salt-water spray. One common user complaint we see with many outdoor speakers is that, despite being graded for outdoor use, they are still prone to rust and corrosion. But we’ve never seen that complaint with any of the Atrium speakers.

There’s definitely a difference between living in a dry, temperate outdoor climate vs a tumultuous climate with humidity and beach run-off. When you consider that along with Polk’s 5 year warranty, and you’re particularly worried about your speakers being especially resilient, then any Atrium speaker will be solid choice.

Our Take

Here’s what we think: These are good speakers… but they’re relatively expensive. The Atrium 4’s do pretty well comparatively to other budget-tier speaker sets – largely because they seem to be significantly discounted these days – but when you move up the line, we’ve seen comparable speakers from other brands such as Klipsch and Definitive Technology boast significantly higher power specs.

A few countering thoughts on this though:

  • There’s more to sound than just specs on paper.
  • User reviews are exceedingly positive, and the Atrium speakers continue to be best sellers despite being 15 years old.
  • We now often see these speakers get heavily discounted. The Atrium 4s are indeed one of our current favorite budget-tier outdoor speakers because you get a lot for the price

However, said again, for the price of the Atrium 5 and up, you can pay the same money for different speakers that are significantly more powerful. A good place to start looking is our best-of round up of outdoor speakers, linked below.

Relevant Links and Resources

Check out the Atrium 4s on Amazon (affiliate link)

See our current picks for the overall best outdoor speakers

See our guide on picking correct outdoor speaker wire