[kramer5150]

curious.... are you by any chance plugging the amp into a wall socket that shares an earth ground return path with a Rheostat?.... Light dimmer knob (if you will). Heck for that matter, are you plugging the amp into a wall socket thats controlled by a dimmer rheostat?

My family room has one of those things and it was emiting all kinds of noise throughout the house AC, and causing intermittent voltage drops / spikes. It wiped out $250 in EL34 tubes in my guitar amps. I since have had an electrician re-wire the house grounds and all is well.

Now I use a furman power conditioner for all my tubes. Although my tube headphone amps seem to be much less finicky than my guitar amps.

Sometihng to consider...

 

[darknix]

Quote:

Originally Posted by Spareribs Secured the power cord? You mean it wasn't all the way in? It was loose? I've never heard about this kind of problem with tube amps but alright, thanks for the info. Keep us posted!

After the amp died, I unplug the power cord on the amp side and found out that the plug was easier to unplug than before, maybe the plug was kinda lossy at the time.

And to Kramer, I don't thing there's a dimmer rheostat connect to the wall socket I used.
I'm only using a surge protector with the amp, and it was fine before today.
I use a computer in the same room and though a UPS, from the UPS's readings the power from the wall socket is pretty clean with voltage within +/- 1V range.
Would that really make a different?

 

[mrarroyo]

Sorry aobut your problem. One of the reasons I prefer Point to Point wiring is because things like these are much easier to fix.

 

[tomb]

It may be possible things have changed with this amp through V1 to V2 to V3 (now "+"?), but there are quite a few threads on the iPod forum and over at Headwize about the Little Dot II burning and taking headphones with it. Maybe the LDII+ has got these problems worked out, but this post makes me think otherwise.

 

[Zowbombs]

Quote:

Originally Posted by tomb It may be possible things have changed with this amp through V1 to V2 to V3 (now "+"?), but there are quite a few threads on the iPod forum and over at Headwize about the Little Dot II burning and taking headphones with it. Maybe the LDII+ has got these problems worked out, but this post makes me think otherwise.

I've gone through several Little Dot amps now and have never had any issues. I've spoken to the seller about this as well and he says the quality control in the current line of amps seems has gotten a lot better than during the time of the headwize group-buy issues.
At that point in time the Little Dot 2 was nothing more than a prototype, and each subsequent revision resulted in higher stability.
One good thing is Little Dot will stand by their work, if bought it from davidzhezhe just contact him and he will get you a replacement with no hassles.

 

[tomb]

Quote:

Originally Posted by Zowbombs I've gone through several Little Dot amps now and have never had any issues. I've spoken to the seller about this as well and he says the quality control in the current line of amps seems has gotten a lot better than during the time of the headwize group-buy issues. At that point in time the Little Dot 2 was nothing more than a prototype, and each subsequent revision resulted in higher stability. One good thing is Little Dot will stand by their work, if bought it from davidzhezhe just contact him and he will get you a replacement with no hassles.

So the explanation is that the LDII was originally just a prototype, but was sold to a number of people whose failure experience including frying headphones? ... and now its gotten a lot better?

Pushing prototyping and quality control down to the customer level is never a good idea - especially if the result may be catastrophic failure accompanied by damage/destruction to the customer's existing equipment.

That's a somewhat mild statement compared to what might be said, but thankfully, I haven't had first hand experience at this.

 

[Zowbombs]

Quote:

Originally Posted by tomb So the explanation is that the LDII was originally just a prototype, but was sold to a number of people whose failure experience including frying headphones? ... and now its gotten a lot better? Pushing prototyping and quality control down to the customer level is never a good idea - especially if the result may be catastrophic failure accompanied by damage/destruction to the customer's existing equipment. That's a somewhat mild statement compared to what might be said, but thankfully, I haven't had first hand experience at this.

Everything is a prototype to begin with. And where is the actual concrete evidence of "catastrophic failure accompanied by damage/destruction to the customer's existing equipment?"
Where is someone who can say firsthand "My Little Dot 2 blew up and took my headphones along with it, and it wasn't because I was an idiot and plugged my tubes in while the amp was turned on?"
Whenever one hears stories like this, it's always "Oh I heard it on this other forum from this guy who had it happen to his brother." Give me a break.

 

[Spareribs]

I still will put faith in this product. I'll still order it next week.
If it lasts just 4 or 5 years, it's ok. By then, I think that there will be other cheaper tube amps with better performance that I want to move on to.

It's part of the head-fi hobby.

 

[Svperstar]

Quote:

Originally Posted by Spareribs Yikes! I'm planning on buying this but if it's an unstable product, I may have to look elsewhere.

Mine works great, ANYTHING can go bad.

For example, the first pair of Sennheiser HD580s I ordered had a bad rattle in the left driver. I took them apart and reset everything, no help, then I looked really close and the left driver had a dent in it

So I had to send them back and get a new pair.

Does this mean Sennheiser headphones are unreliable? No, but anything can screw up.

 

[tomb]

Anything can screw up, but it doesn't have to take your headphones with it. That is the key in the LDII trouble reports. I'm not here to argue the point, though - just to make sure the history was mentioned.

That's done, so buy if you insist, and good luck.

 

[GotNoRice]

What happens to the attached device when a tube fails? Even if there is some risk involved, i'm not too worried about my headphones. But if i'm using an LD2+ as a preamp, could it take out my amp (and my speakers too?). I noticed some of the threads about the quality issues on the LD2 and that was part of the reason I went for the + model instead.