This 1957-1958 Oldsmobile dual voice coil dash speaker is a single 6x9 speaker that will play in stereo. This 1957-1958 Oldsmobile dual speaker has two tweeters on it, one for the left channel and one for the right. The 6x9 speaker cone provides better midrange sound than the dual dash mount speakers as it has more surface area in order to produce those lower notes. With 140 watts of peak power, 70 watts per channel, this speaker will give you high quality sound while maintaining a stock look in the dash of your 1957-1958 Oldsmobile. This is the speaker we recommend for your 1957-1958 Oldsmobile and yes, even over the more expensive Kenwood option.