How does a preamp die from sitting unused for a few months?

C’mon guys, it’s an Inspire preamp built by Dennis Had, in his retirement. I’ve owned 2 and still use one. If it ever failed to power up I’d do the simple thing; Box it up and ship it back to Dennis for inspection and or repair. Dennis, could perhaps fix it for free. He takes a lot of pride in the Inspire brand. So I’d never start scratching my head in wonder about any of his Inspire products. It’s all point to point wiring. So it’s likely an easy fix, and if not Dennis is the one to deal with it. I don’t get all of the mystery, but hey, it’s entertaining. 

OP, did you solve the mystery?

Count your blessing . I recently purchased a pre amp that was in storage . It aent DC voltage to my speakers . Literally had my speakers smoking and my speaker wire arched white when I pulled the wires . 

Use a Varaic to introduce voltage to the pre amp slowly. 

Didn’t read all post so if this was mentioned disregard. Did you check the wires coming off the IEC for cold solder joint. Follow that and see where it goes for bad connection.your definitely not getting power to the rails.I doubt it but handling it in winter static could have done something, 

relative humidity = corrosion.

environmental dust = poorly performing pots.

mouse and rat piss = corrosion an shorts.

rat chews on insulation = shorts

Thanks, all.

The pre is only a few years old (not sure exact date as I’m currently at work) and it was just kept in my spare bedroom which I use for storage.

I’m the only one who handles the gear so no drops, bumps, etc.  And no dramatic change in temp.

Plan to look at the pre again this evening.

invest in a variac and wake up slumbering gear correctly

+1 @builder3 

Old caps and moisture.  Bringing the gear in from the cold, and starting it up immediately without a chance to dehumidify would do it.

Another possibility, related to moisture is salt air. 

If the rectifier tube is burned out would the rest of the tubes and power indicator light light up, or would all electricity be stopped at the first tube (here I'm assuming the rectifier is the first tube)?

@audiodwebe In a word, no.

The tubes are not lighting up because there's no power. So the fuse (which can blow due to current inrush of the filter caps in the power supply, which can be quite a lot higher if the unit has been stored for a while). The second most likely reason is its not plugged in properly.

Depends on the storage. Anywhere unheated, or under-heated can be a problem. Things can draw moisture, which leads to corrosion.

I had an ARC SP 15 that I bought from a guy who had it in storage for years. It popped a fuse the second I turned it on. After replacement it burned up a cap that was swollen and died again. I had to re-cap the thing! Soon thereafter the switched 120v recep. on the back began heating up and failed- broken solder.

For sure the long time unused and maybe bumpity bumps in storage took it’s toll on the unit. After all that the preamp was fantastic and served me well until I bought a Ref 6 SE.

It was fun soldering and tinkering with it. That brought back fine memories of tinkering with old tube radios as a kid. Man I miss the 70s!

Coincidence...something was on the verge.

The pre won't have died from sitting unused for a few months. It died because of something else as per carlsbad2's post. Or it could have been going to expire anyway before it was put away. If it had been put away from years and died from some caps drying out, that would be a different thing - though even that is rare enough.

Did you forget to water it?

DeKay (sorry Roxy)

Comedians everywhere. If only they were funny.

I agree probably lonliness as well. Years ago, I separated one monoblock from the other, and the left channel amp died within just a few months...the right channel has never been the same since 😢

How old is the preamp in question? Look for any caps that might be pooched or leaking. Double check the fuse. I’ve had some blow where it took a magnifying glass to see the break. While you have the magnifying glass out look at the pc boards for any burns or breaks.

All the best.

My Lab12 Integre blew its fuse twice already, and I can assure you when I took out the damaged fuses there was no visual indication whatsoever on the damaged fuses. That's why it's handy to keep spare fuses around. 

I'm guessing the power switch or the rectifier.  If there is a big capacitive element in the power supply there can be a pretty severe shock to the system when first turned on.

+1 @gs5556  .  Always ohm the fuse out.

I'm guessing danager is probably right.  😉

I only visually checked the fuse and didn't do a continuity test with the power cord connector.  I'll try those next.

None of the tubes turn on.  I'm leaning toward the toggle power switch gave out as there is nothing remotely loose or broken off inside.  DHad does some great work!

If the rectifier tube is burned out would the rest of the tubes and power indicator light light up, or would all electricity be stopped at the first tube (here I'm assuming the rectifier is the first tube)?

Thanks, all.

By checking the fuse did you do a visual inspection or did you do a continuity test with a multi-meter? A fuse may look fine but can be broken inside. If you don’t have a DMM replace the fuse and try again.

If that doesn’t work then maybe the power cord is not reaching the connector’s pins. To test this you need DMM. Put in a good fuse, open the bottom plate of the amp, plug in the female cord to the amp’s inlet receptacle (leave the other plug end unconnected from a wall outlet) and test for continuity between the cord’s hot plug and both tabs of the fuse holder. If there is continuity through the plug to the fuse holder tabs then the problem is inside, which definitely requires a service from the factory .

Probably died from loneliness. 

makes no sense

something simple is wrong.

Many ways to look at this. Some failures are time dependent rather than use dependent. Some time has passed. Some failure are vibration or shock dependent. It has been moved so that could cause those. Some failures are caused by accidental mishandling which could have been caused by a cleaning lady or something unexpected during storage.

It could not be a failure but just a mispositioning. My DAC has pairs of RCA connections vertically and for some reason I tend to hook them up in horizontal pairs and then I have to figure out why one channel isn’t working.

Hopefully your failure will be fairly easy to diagnose.

I assume you mean the tubes aren’t lighting up. If multiple tubes aren’t lighting up that points to a fuse or powr problem. I’d open it up and see if there is an internal fuse.

If tubes are lighting up but no music, make sure you have all the connectiions correct. Make sure you don’t have a switch in the wrong position. then replace any tube that feeds both channels.

Jerry

I have an integrated that didn’t power up for years after unplugging it for a vacation. Works fine now. Some questions are unsolvable.