Koss Pro4S Full Size Headphones Let You Go Pro for Under $150

My first over-the-ear headphones were made by Koss. That’s going back almost 40 years. The Koss Pro4S headphones hearken back to those headphones for just $149.99. More importantly, these full size, over-the-ear headphones are super-comfortable and sound fantastic. Designed for professionals but priced for the consumer market, I’ve been more than mildly impressed by them. Let’s check them out!

Koss Pro4S Full Size Headphones Let You Go Pro For Under $150

The Koss Pro4S headphones come in a simple box but include a case that will help keep them safe when you travel. And while these aren’t headphones sporting active-noise cancellation, they do block out a good bit of ambient sound. That means you don’t have to crank up the volume in order to hear your music with all the clarity they deliver. And they do deliver crisp, clean sound!

Koss Pro4S Full Size Headphones Let You Go Pro For Under $150

Here’s what the company has to say about them:

“The Pro4S Studio Headphone is specifically crafted for professionals who use headphones every day to create the world’s greatest music. Featuring the all-new SLX40 element, tuned for reference, the Pro4S Studio Headphone delivers an incredibly accurate and unbiased sound, perfect for any studio or creative environment.”


“Designed for the rigors and wear of professional use, the Pro4S Studio Headphone features an incredibly rugged mechanical design using the most durable materials. Aluminum earcups with memory foam cushions wrapped in soft protein leather make the Pro4S Studio Headphone structurally strong but incredibly comfortable. An all-new integrated, metal-on-metal assembly of the headphone makes the Pro4S Studio Headphone extremely robust in areas where other headphones often fail. The metal headband is cushioned by soft foam wrapped in breathable mesh, perfect for extended use.”

Koss Pro4S Full Size Headphones Let You Go Pro For Under $150

The first thing I noticed upon pulling the headphones out of their case was the sturdy design and the degree to which they fold flat for storage and travel. They feature a detachable cord and there is a 3.5mm port on both the left and the right ear cup. That means you can choose which side the cord runs from depending upon how and where you are wearing them. Koss went one step better though. While one ear cup receives the included cable- there is no microphone or controls on it- the port on the other ear cup becomes an output port. This allows you to daisy chain headphones and share the audio with someone wearing a second pair of headphones.

Koss Pro4S Full Size Headphones Let You Go Pro For Under $150

Add in the fact that the cable has it’s own pouch inside the storage case and the headphones themselves fold flat and you have a pair of professional grade headphones that can go anywhere you do.


  • Full-size, over-ear Studio headphones
  • D-profile with memory foam cushions
  • Koss SLX40 Elements tuned for studio reference
  • Detachable cord with dual choice entry
  • Fold flat for portability
  • Carrying case
  • Covered under the Koss Stereophones Limited Lifetime

The two most important aspects of over-the-ear headphones are the comfort and sound. If the headphones aren’t comfortable you aren’t going to wear them for extended periods of time. If the headphones don’t sound good you aren’t going to use them at all. The good news is that the Koss ProS4 headphones are both comfortable and great sounding!

The Pro4S Studio Headphones feature “the natural fitting, iconic “D-profile” ear-cup, first featured on the ergonomically designed Koss Pro4AAA.

Koss Pro4S Full Size Headphones Let You Go Pro For Under $150

The D-profile mimics the shape of the ear. For this reason the left ear cup is specifically for the left ear and the right ear cup is for the right ear. There’s no flipping the headphones around but, since there is a port on each ear cup this won’t be an issue. The design is significant since it creates “an ideal seal for the most consistent sound reproduction and an incredibly natural fit for extended creative sessions.” The seal is rather excellent and makes for a comfortable fit. The headphones are tuned to sound natural and offer clear, crisp sound that lets the music speak for itself.

For those of you who like numbers the specifications are as follows:

  • Frequency Response:10-25,000 Hz
  • Impedance:35 Ohms
  • Sensitivity: 99dB SPL
  • Cord: 4.5ft/1.4m Coiled, Detachable with Dual Choice Entry

Koss Pro4S Full Size Headphones Let You Go Pro For Under $150

In all, I’m a fan of the Koss Pro4S headphones. They are light and sound great. Best of all, at under $150, they are accessible to most consumers. Check them out here.

Source: Manufacturer supplied review sample of the Koss ProS4 headphones.

What I Like: Comfortable; Dual inputs; Great storage case; Daisy chaining possible; Pro headphones with a consumer price.

What Needs Improvement: Cable has not controls or microphone.

As an Amazon Associate, we earn from qualifying purchases. If you are shopping on Amazon anyway, buying from our links gives Gear Diary a small commission.

About the Author

Dan Cohen
Having a father who was heavily involved in early laser and fiber-optical research, Dan grew up surrounded by technology and gadgets. Dan’s father brought home one of the very first video games when he was young and Dan remembers seeing a “pre-release” touchtone phone. (When he asked his father what the “#” and “*” buttons were his dad said, “Some day, far in the future, we’ll have some use for them.”) Technology seemed to be in Dan’s blood but at some point he took a different path and ended up in the clergy. His passion for technology and gadgets never left him. Dan is married to Raina Goldberg who is also an avid user of Apple products. They live in New Jersey with their golden doodle Nava.