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Red-Eye Preamp - Battery Problems

Red-Eye Preamp - Battery Problems



My Red-Eye has been great, but it just quit working in the middle of a gig this weekend.




Please test the battery.   90% of returned Red-Eyes simply have an exhausted battery. 


Normally, most users connect via the XLR connector to a sound system.  Normally, the sound system supplies Phantom Power to the Red-Eye and the Red-Eye’s battery is not used.  The battery is there for “insurance”, so you can play if you hit an old venue that doesn’t have Phantom Power, or if the sound tech forgot to turn on Phantom Power to your channel.  As long as Phantom Power is actually present, the battery is not used.


Fire-Eye products are designed to use the International Standard 48-volt Phantom Power.  Some small sound systems and mix boards supply lower voltages that will not adequately power Fire-Eye products.


Players may not realize that, on occasion, they are not getting Phantom Power and are actually running on the battery.  So every once in a while try the battery check, below.  Battery life running on the battery is about 200 hours for the Red-Eye and about 100 hours for the Twin.


Power Check Light...

Both Red-Eye models have a Power Check Light.  On the single-channel Red-Eye it’s right next to the Instrument Input jack.  For the Twin, it’s at the upper left corner of the top.


Red-Eyes have a power check circuit that runs each time the Red-Eye is powered up.  If internal circuit power is good, the check circuit flashes the Power Check light for one second.


If the XLR cable is plugged in first (before an instrument cable is connected) the Red-Eye will power up on Phantom Power from the XLR cable.  If the light flashes for one second, Phantom Power is good.


When an instrument cable is plugged into the Instrument Input jack (before the XLR cable is connected) the Red-Eye will power up on the battery and the light will flash for one second if the battery is in the first ¾ of its life.  If the light doesn’t flash, the battery is in the last ¼ of its life or is exhausted.


Battery “surface charge”…

If a battery is exhausted and is not used for a few hours, it can develop a temporary ability, called a surface charge, to support a light load.  The Red-Eye electronics draws very little power and an exhausted battery with a surface charge can run the Red-Eye for 5 or 10 minutes.  If the Red-Eye’s Solo Boost is turned on, the Boost Light turns on.  The light actually draws more current than the analog electronics and will exhaust a dead battery’s surface charge immediately.  When a customer calls and says “My Boost Button is bad.  My Red-Eye runs fine until I turn on the Boost.” the problem may simply be an exhausted battery and no XLR Phantom Power available.


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alex - May 14, 2018

I have been using the red eye for a couple of years at present with the K&K pure mini pick up . I have been going out on small venues using my schertler unico amp and have found that the XLR puts out a great signal, but when I have to use that circuit for a condenser mic I go in to the 1/4 jack and have found it looses a tremendous amount of volume level. I check the battery and it has 120 hours of batter life left.

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