Fried my Raven Labs PHA-1

johnbee · #1 07-13-2012, 03:48 PM

Okay, get a load of this...

I had my Raven Labs PHA-1 headphone amp sitting next to my home stereo receiver. Each one had a min-aux cable coming out of it. You see, sometimes I practice to the iPod out loud with the stereo, and sometimes I practice to iPod, quietly with the PHA-1.

Well, wasn't paying attention and connected the wrong things. Apparently I put the aux-out from the home stereo into the AC-in on the PHA-1. The result was a loud 'POP!' from the PHA-1. (I *think* that's what I did, but it was a few weeks ago and now I'm not exactly sure. Except that I connected *something* wrong and fried it.)

Now the PHA-1 works okay most of the time, but if i turn the bass input up past 50%, it will randomly shreik and/or pop, totally hurting my ears. And I can't turn it on with the headphones on because that makes a loud pop pretty much all the time. So it works 99% of the time, but the other 1% it's gonna make me go deaf.

Can something like this be repaired? Or do I need to just keep hitting the forums until I find a used replacement? Bummer cuz I loved that thing.

Advice is appreciated...

Derek Balonek · #2 07-13-2012, 05:29 PM

It's probably fixable, the question is just what needs fixing and if it's worth it.

What kind of power does it take? If it's an external (wall-wart) then there could have been damage to some of the audio path stuff. You said you plugged the aux out into the AC in? If it's AC power that it takes, then there could be damage to some internal power supply parts.

I'm not quite sure if that could damage it, or how. Assuming it takes AC, the power that it takes from the wall is probably greater than what the stereo puts out. If it takes a DC wall-wart, then I could see it damaging some important internals as the active components would get some less than happy voltages.

To the main issue though, repairing it is probably not cost-effective unless you go the DIY route (yourself or someone you know) as getting a tech to diagnose and fix whatever has issues tends to get expensive.

randy clere · #3 07-13-2012, 05:35 PM

it is WORTH fixing! These are rare, and anyone who has one knows these are little gems of a preamp! FIX IT!

AN0INTD · #4 07-13-2012, 05:43 PM

Sorry to hear that!

As far as repairs go, there is supposedly someone in charge of repairs after RL went defunct (see post #9) : Raven Labs PHA-1 - questions

I don't know if he is still active, but it couldn't hurt to try contacting him. Good luck

jeffbonny · #5 07-13-2012, 05:55 PM

Quote:

Originally Posted by randy clere

it is WORTH fixing! These are rare, and anyone who has one knows these are little gems of a preamp! FIX IT!

+1,000,000,000!
My Raven Labs PMB is one of the few pieces of gear I own that will never be for sale as long as I can hold a bass.
You might have a bit of search to find another PHA-1.

johnbee · #6 07-13-2012, 08:24 PM

Thanks everyone. I guess it is worth taking it to someone who does amp repairs and see if it is something they can figure out easily. I don't know how this stuff works, but I guess they could use some kind of circuit tester to see where the failure is. I just had this fatalistic feeling that it would cost more than just replacing it. Of course, you have to wait a while for a used one to come along...

I should also do a test by trying it on battery power and seeing if the problems still happen. I didn't try that yet.

Jim C · #7 07-13-2012, 08:40 PM

+1 to the battery test although I would guess that you have cooked a component or two that makes the unit unstable
These are really good small units

johnbee · #8 07-17-2012, 10:57 AM

Same results on battery power. Specifically: When you turn the unit on it makes a very loud 'pop' in the headphones, even if the volume is all the way off. And if you turn the main volume up past 50% it will sometimes shreik very loudly. Both of those will fry my headphones and my ears.

Does anyone have leads on where to take this to get it repaired? I am in the SF Bay Area.

Skrogh · #9 07-17-2012, 04:26 PM

Try open it and look for burnt chips or capacitors. If you say you put in a wrong PSU, the over-voltage might have killed a capacitor, look for a dent in the silver top or brown residue on it.

johnbee · #10 01-08-2013, 06:39 PM

FYI, I took it to a local shop "The Amp Lab" in Campbell, CA. He warned me he was back-logged and would need to keep it for "a while". That was certainly true.

But I picked it up the other day, and it works perfectly! He said it was a fried resistor plus some bad grounding at the jacks. Total cost: $70. It was so worth it!