The AKG HP12U 12-Channel USB Headphone Amplifierfrom AKG HP12U 12-Channel USB Headphone Amplifierfeatures two stereo input and six stereo output channels, each with two 1/4" outputs. It can be used to easily monitor your analog or digital equipment – without rewiring your headphones – by switching between inputs A and B.

Simply connect multiple units if you need more channels. In addition, the HP12U can also be used as an external sound card by connecting input A to your computer via USB. Housed in a sturdy chassis, the HP12U is an ideal headphone amplifier for any recording session.

6 x Stereo Output Channels    2 x Headphone Outputs per Channel    2 x Stereo Input Channels    Selectable Source Input    Volume Control on Each Channel    Built-In USB Computer Port

Related Questions and Answers

Q: 1. Any idea how much amplification is added to the signal?

A: AKG lists the nominal output as 680 mW per channel into 32 Ohms.

Q: 2. Will this unit drive a 250 or 600 ohm headphone with plenty of power to where I don't feel like I need a higher power amplifier?

A: This headphone amplifier is designed to handle high impedance headphones, so it will have enough power for 250 or 600 Ohm headphones.

Q: 3. Will this unit drive a 250 ohm or 600 ohm headphone player with plenty of power, to where I don't feel like I need a higher power amplifier?

A: The specs show power of 600mw with 32 ohm headphones. One must also consider: 1- the headphone sensitivity specification, which will tell you how loud a headphone is, based on the power applied. 2- the transients in whatever it is you are listening to; large transients requires much more power. see below article of explanation: https://www.audeze.com/blogs/technology-and-innovation/sensitivity-impedance-and-amplifier-power

Q: 4. 12 V, 500 mA is the requirement for the power adapter for the AKG HP4E according to the specs. Question: Is the tip positive or negative?

A: The manufacturer has not specified whether the power supply for the AKG HP4E 4-Channel Headphone Amplifier has a positive or negative tip, however, a dedicated power supply included with the HP4E.

Q: 5. Will the input B on the back accepts quarter inch input? I see a XLR and a quarter inch jack there.

A: Channel B has XLR connectors. The 1/4 inch connectors are for channel A and the link outputs.

Q: 6. Will this Rolls RA53B shipped with 220V power adaptor?

A: The 12 VDC Power Supply included is designed to accept 120 VAC only.

Q: 7. Can multiple headphones listen to the same content?

A: That is literally the only thing this product does.

Q: 8. Do the inputs of this unit sum? Or does one input override the other? I need an amp with at least 2 simultaneous inputs

A: The Rolls RA53B 5-Channel Headphone Amplifier has 3 sets of right/left input connectors. Either the XLR or 1/4" right/left inputs can be used to connect 2 separate line-level signals.

Q: 9. Se puede conectar a una laptop?

A: Yes you can connect the Samson QH4 to a laptop using this cable B&H # PEMMSA106B.

Q: 10. Is it possible to operate it in mono using the XLR connection or only when using the 1/4" connection?

A: Thank you for your question. for mono operation you would need to use the right 1/4 inch input only.