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Microphone inputs not working on Delta 1010LT
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Q: I am trying to connect my microphone to the XLR inputs on the Delta 1010LT, but I am unable to get any signal into the Delta Control Panel or my recording software.

A:  The Delta 1010LT does not provide phantom power, which is required by most condenser microphones in order to operate; only dynamic mics can be directly used with the 1010LT.  In order to connect a condenser microphone you must use an in-line phantom power adapter, or you can use an external phantom power mic preamp.  Additionally, the XLR inputs on the Delta 1010LT can be set to accept microphone or line level signals.

The Delta 1010LT’s PCI card has two sets of jumpers that can be used to control the operating line level for the 1010LT’s analog inputs 1&2 on XLR jacks. The location of these jumpers is illustrated in the Delta 1010lt User Guide in the “PCI Host Adapter Card” section.  Two basic settings are possible, one for a microphone level compatible with low impedance dynamic microphones (those that do not require phantom power), and the other is an operating line level of +4dBu (typical for balanced line levels).  Two variations are possible for each of these level settings.  This is shown in the illustrations below.

The default setting when you receive your 1010LT is with the jumpers set to the microphone level setting.  If you wish to use either or both inputs 1&2 as a +4dBu line level input, then you will need to change the jumper setting on the 1010LTPCI card.  Changing the jumper setting is easy to do, and should be done when the 1010LT PCI card is not installed in the computer.  If you wish to connect a dynamic microphone directly to the Delta 1010LT’s XLR analog inputs 1&2, then leave the jumpers set to their default setting, which should be Mic Level +30dB gain.  If you wish to connect the XLR analog inputs 1&2 to the output of a balanced +4dBu device such as an external phantom powered pre amp or mixer, you will need to change the jumper setting.  Remember that you can change one set of jumpers and not the other, if that suits your needs. To change the jumper:

  1. Before removing the Delta 1010LT PCI host card from its protective anti-static bag, touch the metal power supply case of the computer in order to dissipate any static electricity your body may have accumulated. You might want to pick up a grounding wrist strap (available from electronics stores like Radio Shack) if you want to be doubly sure you aren't carrying a static charge that could damage the card.
  2. Either hold the PCI card in your hand, or place it on an anti-static surface (such as its protective bag).  Using your fingertips or a tweezer, remove the plastic jumper that is covering the top-most and middle metal pins. See Illustrations 1 and 1a, below.
  3. Place the jumper over the middle and bottom-most metal pins. See Illustrations 2 and 2a, below:


NOTE: Illustrations 1a and 2a show a variation on the mic level setting and the line level setting, respectively.  If you find that your signal is too hot using the +4dBu selection in the Delta Control Panel, then try these alternate settings.