• TalkBass has been independent since 1998. Add your voice.
    Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
    Join free Log in
    Want zero display ads or expanded classifieds tools? Compare plans.

Power Light Won't Illuminate

R

rockinroller

Dec 6, 2010
32
1
#1
I just bought a new Acoustic B450 bass combo amp. Great amp--punchy, lots of power, wide range of EQs, etc. Guitar Center was clearing these out and I received a floor model from an out of state store. The amp light won't illuminate. I slid out the amp and verified the wiring was connected, the two point harness was plugged in, etc. and I even spliced in another lamp assembly I picked up at the local Radio Shack. Nothing.

Does anyone have an idea of what could be the issue? The amp works fine--just no visual indication of power. Acoustic has a nice 3 year warranty but there's no service location near me and I'd have to have it shipped out to have this fixed.
 
#4
rockinroller said:
The amp light won't illuminate. I slid out the amp and verified the wiring was connected, the two point harness was plugged in, etc. and I even spliced in another lamp assembly I picked up at the local Radio Shack. Nothing.
Click to expand...
What kind of lamp is it? LED, or incandescent, or neon?

Where is the lamp voltage obtained? Direct from the AC line ("this" side of the switch), or from some low-voltage source?

This would be a good application for a voltmeter because you could tell exactly what (if anything) is present at the lamp end of the wire pair.
 
#6
I don't know what type of lamp it is. Radio Shack's fairly knowledgeable guy said he thought it looked like an LED. The light's two-wire harness plugs into a 2-hole female receptacle on a circuit board. That's the extent of my understanding of this situation.
I have a house-type electric tester (that detects juice in a line) if that would work.

I am inclined to align with Johntheson's perspective: Keep the amp and forget about the power light issue. Heck, with the absence of anything other than one-night gigs, there's no chance of leaving that amp on anyway, plus the cooling fans are loud enough to know whether the thing's running.
 
#7
Ok, it sounds like an LED. No, an AC outlet tester (if that's what it is) won't work. You need a low-voltage voltmeter. You have either a bad LED or a bad driver circuit. But yeah, if the fan suffices as a power-on indicator, then I guess you don't need to go further. Another thing you can do is buy a cheap power strip with an illuminated rocker switch, and use that as the amp's power switch.
 
#8
Well maybe the Radio Shack replacement that didn't work either would never have worked anyway, as it was a standard Neon Light Assembly with 120VAC operating voltage and 95VAC firing voltage, based on the packaging.
Is that possible?

If so, where could I find a replacement light that I can 2-wire into the type of connection this Acoustic uses? Acoustic support is no use, as they do not provide an outlet for parts for owners.
 
#10
This is making no sense. The RS expert said it looked like an LED, but he sold you a neon lamp assembly?

If you want to pursue this, you have to find out what voltage is at the lamp assembly end of that cable. Voltmeter time. Be careful in case it IS line voltage, 'cause that can knock you right into next week if you come in contact with it.
 
#12
rockinroller said:
Yeah, I chose the neon lamp assembly because it looked more compatible and similar to the entire harness I was trying to replace (the LED was just a small bulb at the end of two thin wires).
Click to expand...

From your description it uses a micro minature bulb mounted on a small flat circuit board. We use them at work. These bulbs look like the minature bulbs you use to find on a Lionel train set. They dont last very long. The neon bulb should last for a long time and be much more reliable.
 

Latest posts

Top Bottom
Back