NOT FOR USE WITH HEADPHONES!
Sound Shocker will not boost the volume into a set of headphones. Using Sound Shocker with headphones will actually lower the volume.
Keep in mind that all Sound Shockers are designed to work with headphone outputs only. Many dock outputs, Bluetooth, GPS, satellite receivers etc. have high impedance line outputs and can not drive headphones. Some of these devices will work just fine with Sound Shocker, others will not.
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