[tommystery]

Alright, so I turned on my stratos this morning; Klaus is going to kill me but it's an ODL.  If you read back on the forum I bought it blindly and thought I was getting the real thing.  I had even come on this board to post a rave review of the product compared to my previous amp, and that's when I found out that it wasn't the real thing.  Anyway... onto this morning's story...

I turned on my Stratos, I think I heard the relays flip for a second and then flip back; but there's no sound coming out of the unit.  I opened it up and there was a lot of smoke.  All the fuses are intact and there is no visible burning aside from the resistors beside the relay on one channel (see picture).  However neither of the channels are working.  Does anyone have any ideas?

I have some soldering experience so this is something I could probably fix myself if I knew which components to replace, what I'd like to really know is what caused it to blow up in the first place though.  It was working fine last night.

Thanks,
Rob.

[tommystery]

Ok a small update, I plugged in the unit and turned it on.  The channel on which the resistors are blown the relay turns on.  The other one doesn't, so I would assume that there is no damage done to the other channel as the relay never turned on.

[jqp]

Is this even an Odyssey amp then? Maybe this should go in The Lab.

[tommystery]

From what I know it's a long story, but Klaus's parthner stole the schematics for the Odyssey and started producing his own gear under ODL.  The amp is identical to the Odyssey; had I known this before buying it though I wouldn't have bought it for both ethnical reasons and the fact that it's not backed by Klaus's 20 year warranty.

Here's another update....

The issue wasn't caused by the amp but by the preamp that I'm using.  I have a tube preamp which has 3 12ax7 tubes and a 6x4 recitifier tube.  I measured the outputs on the preamp and they were oscillating.  I replaced the 6x4 with another tube that I had lying around and everything seems to be fine now....

So it appears like the amp was surged with the preamp's max output which is 20V.

Ouch.... I'm probably looking at replacing about half the topology and input caps aren't I?

[Marbles]

Call Klaus, 317-299-5578

[tommystery]

When is a good time to call Klaus?  I'm in the EST timezone.

[TomS]

Evening is the best time (EST)

[avahifi]

My best amplifier technician has told me that during the manufacturing process, all passive parts, along with some semi-conductors, are filled with magic smoke under high pressure. 

When one of those parts cracks, due to some stress or overload, then all the magic smoke escapes, and the part is ruined.

I know this is not very helpful, but then neither is the fuzzy photo of "something". 

Trying a bit harder, the relay is likely sensing DC offset at the output of the amplifier (a typical use, I do not know the specifics of this design).  If a channel fails or goes DC offset too far, the relay opens, or will not close, thus protecting the speaker from a bad amp channel.  Many amplifier have a single "stereo" relay activated by either audio channel, so if one channel misbehaves, neither channel will have output.

Note too that a failed (overheated) resistor is almost always caused by something else that has failed, pulling too much current through that resistor.  In general, you must find the source cause of the failure, simply replacing a smoked resistor likely will not fix the problem.

Regards,

Frank Van Alstine

[tommystery]

Reply to Avanhifi;

The relays are used as a delay circuit to prevent speaker inrush current.

What happened today, was caused by my preamplifier which fell into oscillation because of a faulty 6x4 recitifier tube.  The preamplifier's peak output voltage is 20V whereas the maximum input voltage on the amplifier is 2V; or so I believe.  I think that the high voltage caused the caps to discharge and surge one of the channels.  Because the delay had already activated in one channel but not in the other only one channel was damaged.  Interestingly enough, none of the fuses blew, and the other relay (from the channel which appears undamaged) refuses to activate.

In either case, I don't have a schematic for Klaus's work so I cannot exactly say how the amplifier works.

There was quite a bit of that magical smoke though when I lifted the cover of the amplifier... much more than I would expect from two resistors.

[rosconey]

call klaus-
 he may take pitty on your soul

klaus is a stand up guy-i bet he does you right

[TomS]

All I can say is "ooh ooh that smell..."

[tommystery]

Yes... that horrible smell.

Anyway; I called Klaus and he had already read this thread so he was expecting my call.

He honestly must be the nicest and most helpful guy around.
Klaus, *Kudos*

After talking to me on the phone for about half an hour, as if I was one of his own customers I'm going to send the unit in to him.

But considering how nice he was I'm probably going to go ahead and overhaul the whole unit with a new board to a Stratos Plus with the 120 000uf cap upgrade.

Honestly though; a lot of companies could learn a thing or two from Klaus about customer service.
 

[TomS]

Klaus is der man

[F-100]

Honestly though; a lot of companies could learn a thing or two from Klaus about customer service.
 

That is the main reason why I still have my Odyssey amps after 6 years and several upgrades because I know that Klaus will be there and take good care of you if I have any problem with the amps. 

[Eduardo AAVM]

Honestly though; a lot of companies could learn a thing or two from Klaus about customer service.
 

That is the main reason why I still have my Odyssey amps after 6 years and several upgrades because I know that Klaus will be there and take good care of you if I have any problem with the amps. 

I agree, many people think the issue is if a product fails or not, for me it is more important when something fails how fast and how good the problem is solved and Klaus can teach a lot on the matter.

[lazydays]

one thing that just stuns everybody that listens to my amps and preamp is the words "made in the USA." Then I tell them that his company is local, and their eyes light up. Very hands on, and no salesman hype period! The last time I spoke with Klaus the first thing he wanted to know is what the system sounded like. He's never tried to sell me anything. Yet he's always there, even after the sale to get me thru the latest quagmire. The salesman gets your money and forgets your name within ten minutes.
    Now if he'd just make a pair of 30 watt SET's and a two input phono stage I think we could elect him governor of Indiana.
gary

[DMi]

Frank's right. Smoke is supposed to stay inside, it's the magic that makes things work.

If you haven't called Klaus you probably should and throw yourself on his mercy as others have suggested. He is busier than that proverbial one legged man right now but he will likely be helpful to you.

It's sad to hear that the pre-amp may have caused an issue but tubes have magic too and sometimes when that magic goes "black" you end up with too much DC or DC offset passing to outputs. It totally depends on the design but it's certainly possible with some tube preamps and amplifiers. Generally that is bad for anything downstream, in a lot of cases fatal. You may want to have that checked out also. 

I hope Klaus helps you out and your back online with the Stratos (half breed or not) soon.

Best of luck,

Doug

[tommystery]

The damage was caused by a faulty 12AX7 tube (it wasn't the recitifier tube as I had originally thought), one of the pentodes on the secondary output stage was burning out and caused a clipping signal to be sent to the amp.  (When I connected a QSC MX1500a that I have, I saw the clip light going on and off and a loud hum in my speakers.)  I'm assuming that because this was the ODL amp it wasn't biased properly and couldn't deal with the current when the capacitors discharged due to the peaked signal.

Also, if Klaus reads this forum;  I'm finally sending out the amp tomorrow.  I have encased it in 2-inch styrofoam  

It will be sent from a different address than mine (my address is on a printed sheet I included inside the box describing the problem and other things we talked about on the phone.)  The reason for this is because my friend works for a shipping company and he gets 80% off on shipping.