Great value for the money
As a recording engineer and microphone engineer for 30 years, I'm often looking for headphones with a wide-range, neutral sound. I wanted an affordable backup for my preferred headphones, AKG K271 MKII which I gave 5 stars in a Sweetwater review.
The Sennheiser HD 201 ($29) comes close to the sound of the AKG K271 MKII ($199) for about 1/6 the price. Starting with the low end, the HD 201 has tight, deep bass that is more emphasized than the AKG. In other words, the Sennheiser seems to have a little too much bass for accuracy, but it's probably marketed to many listeners who like extra bass
If you wear eyeglasses while using the Sennheiser, their frames create a small leak in the 'phones air seal which reduces the bass to a more-accurate tonal balance, in my opinion.
In the midrange, the Sennheiser really shines. It's an uncolored, smooth sound that does great justice to the human voice. The treble frequencies (cymbals, etc.) sound smooth as well, if a little diminished compared to the AKG.
Construction is sturdy and the 'phones are comfortable to wear. They have a little more pressure on the head than the AKG.
I took off 1/2 star for the exaggerated bass, but otherwise these 'phones give a lot of bang for the buck.