Dying Amp?

[elementxero 10+ year member]

Alright. I found out something odd while setting my gains but this isn't related to gain setting so I made a new thread:

I have had bad vibes from this amp since I bought it here, but I don't want to assume anything.

Here's the deal:

The amp makes a very odd hissing/humming sound that doesn't sound like a fan.

The amp produces almost ZERO sound output with the head unit at 28/35 and the gain up 1/3 of the way.

The seller said that he always had the gain at zero. The reason is because he had what he kept calling a "bass module" which amounted to a phone jack plugged into the remote bass plug with a plastic tube on the end. What's hooked up in there is anybodys guess.

With this 'module' plugged in, the output is suddenly heavy even at a zero setting.

Now, and here's where it gets sketchy, when I take an AC Voltage reading from the + and - output terminals, the meter reads anywhere from 60 to 190VoltsAC, regardless of gain!

It doesn't remain static either it jumps rapidly around in that range. I'm definitely probing the same metal that my speaker wire connects to, and the meter works fine as I set my RF2002's gains perfectly smoothly right before this.

So, my theory is that this amp is as much of a POS as it looked when I got it. If this is the case its paypal investigation time.

Thoughts?

ps- excuse the long post but I'm kind of heated at this point and I want to make sure I don't jump to conclusions.

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[elementxero 10+ year member]

Bump for an itchy paypal complaint finger.

 

[elementxero 10+ year member]

bump

 

[DiDan 10+ year member]

some amps will only work with the remote bass knob attachetd to it. so this part of the story can be OK.

but the voltage at the output should be constant playing a sine wave @ 60Hz.

with music your ac meter will not read right numbers as it needs constant 60hz.

DiDan

 

[elementxero 10+ year member]

I was playing a 60Hz sine wave from realmofexcursion.com

 

[elementxero 10+ year member]

Also the output definitely varies. The same song at the same volume level can be either barely audible bass or distortion laiden heavy bass. This much deviation is rare.

What isn't rare is that it seems to need time to "warm up" before it hits and seems to slowly get louder. I noticed this on the way to work this morning. I was listening to a NoFX album and the kick drum started off almost absent and by the time I got to work it was close to overpowering the fronts.

 

[Boomin_tahoe 5,000+ posts]

some amps will only work with the remote bass knob attachetd to it. so this part of the story can be OK.
but the voltage at the output should be constant playing a sine wave @ 60Hz.

with music your ac meter will not read right numbers as it needs constant 60hz.

DiDan

BS. Then the amp would be worthless w/o the bassknob. I've never heard of an amp not being able to function properly w/o a bassknob. A bassknob is an option with the amp.

 

[elementxero 10+ year member]

BS. Then the amp would be worthless w/o the bassknob. I've never heard of an amp not being able to function properly w/o a bassknob. A bassknob is an option with the amp.

Me neither which is why I want to know if this amp is screwed over. Output wildly varies, makes a sketchy sound, and won't work without the bass "module" (crudely put together plastic tube of mystery).

**** it I'm putting in a paypal complaint, for 220$ I could almost get the DA7401 for sale in the classifieds. This douche is getting his trash back.

 

[Boomin_tahoe 5,000+ posts]

Yea man. If you can w/o turning it into a big mess. Your def in the right place to be askin tho. Good luck.