I bought these earplug style headphones to use with my new Creative Labs Zen Sleek MP3 player while traveling. Here are my impressions so far:

Construction

The Spark Plug earplugs are not terribly impressive right out of the blister pack. The overall construction seems rather fragile, with very thin wires connecting to each earpiece. The part which you put in your ear is foam, like cheap foam earplugs you might use to block out loud noises. The foam, and these headphones in general, do not seem like they would hold up well over time or with heavy usage. On the plus side, at least the 1/8" mini-plug is gold-plated.

Appearance

The appearance is not outstanding, but not terrible either. The earplugs have a hard plastic piece that does not go in the ear, connected to the foam pieces that are inserted into the ear. The hard plastic piece is white and ridged, looks a bit funny, and is very visible sticking out of the ear. For those who are as concerned about appearance as they are sound, these headphones would probably not be a good choice. So you probably won’t see Lindsay Lohan wearing a pair of these anytime soon.

Noise Blocking

The foam earplugs do block out some ambient noise. There is a tube down the center of the foam earpiece that the sound travels down, and I suspect that some outside noise manages to travel through this path as well. The sound blocking capacity is definitely not going to be enough to drown out the sounds of a bus or airplane. So if you were considering these to try to drown out the sounds of obnoxious children (or adults) on your next trip, you might want to consider some more substantial earplug type phones.

Comfort

To put these headphones in, you compact the foam earpiece and stick it in your ear. The foam expands to fit the shape of your ear. They are decently comfortable for about an hour, becoming somewhat uncomfortable after that. They do stay in the ear fairly well, and are lightweight.

Sound

Right away, I noticed that these earplugs do produce a minor amount of static. It is relatively inconsequential, and I don't think many people would even notice.

The other problems with the sound are significant. First of all, the sound is very dark. In other words, the higher frequencies are noticeably muted. This extends down far enough that vocalists sound somewhat quieter. Everything further up the sound spectrum drops off quickly. The bass, especially the mid-bass, is very strong, to the point of being almost overwhelming. The effect is rather like being in a house with a band that is performing. Except you are in a room with the bass player and drummer upstairs, and the rest of the band is performing in the basement. And somebody stole the drummer's cymbals, which they may be playing in that room far away.

I compared these earplug style phones to a wide variety of headphones, from cheap phones that came with my Panasonic CD player all the way up to my Grado SR-125s. All the other headphones that I tried sounded much better than these headphones. Since then, I have purchased a pair of Sony clip on type headphones which sell for about the same price as the Spark Plugs. The Sony headphones also sound a lot better than this Koss model, with a much more balanced overall sound. I would also recommend considering the Sennheiser HD201 in this price range.

Other Considerations

The impedance of these earplugs is pretty low, at 16 ohms. That means these will play quite loud with normal portable devices, like MP3 players or CD players. Unfortunately, with the dark sound, you might need to turn it up quite a bit to hear the music, and the bass will probably just overwhelm everything anyway.

The cord length is 4 feet, which should be adequate for the most likely use, which is with a portable device.

The package includes a second set of foam earpieces, which is good, as the first set is likely to wear out or get dirty fairly quickly. The earpieces slide off very easily, making them easy to replace, or lose.

Overall

I wouldn't recommend these stereo earplugs to anyone, not even the extreme bass lovers out there. The overall sound is very dark and disappointing. The appearance is rather boring and slightly dorky. The comfort is mediocre. These headphones retail for around $20. For that price, there are many other options available. Try something else instead.

Other headphones worth considering:

Sennheiser HD201 - 3 stars, approximately $20

Sony MDR-Q22LP Headphones - 3 stars, approximately $20

AKG K 26 P Headphones - 4 stars, approximately $45

Grado SR-125 - 3 stars, approximately $125-$150

Sennheiser HD-580 Headphones 5 stars, approximately $200



Recommended: No