[Draygonn]

silly question but have to ask.. maybe the batteries just need charging?

 

[turokrocks]

 
Quote:

 
silly question but have to ask.. maybe the batteries just need charging?

 

[Willakan]

We're not actually joking: When the batteries in the O2 are low enough to potentially cause problems, it drops into a "stand-by" mode, where the power LED still illuminates but no sound is heard (if memory serves, mine is a AC wallwart-only build), which if you didn't know would seem exactly like a broken amp!

 

[pinkfloydfan]

Quote:

I purchased on O2 from a builder in England, and it stopped working after only a few hours use.   I assume I cannot mention the builder by name since they are a sponsor here at HF.  The builder is not returning my emails.  

I was wondering if I was the only one with problems until I saw your post, mine had an intermittent channel which happened after it had been on for a few hours, I never got a reply either from Epiphany Acoustics & since I got this for a trip coming up shortly I couldnt wait any longer, it took enough time to get one in the first place & now this! (YIKES)

, I made a pimeta amp a year ago & so luckily I can solder (just about)

so I opened up my O2 & had a look around to see if there was a wire off or something easy that I could fix save sending it all back with more waiting, but nothing, then I noticed a few poor looking solder joints on the board so redone those & to my suprise DADA!!! its working again

, I should have probably bought the board only & made it myself but I was lazy & assumed that somebody else might do a better job

, phew at least its fixed now, crysis over, now that I have had a proper listen I just have to decide which of my portables is best for my headphones, the verdict is still out on that one but my Pimeta is proving hard to improve upon but it does have better parts, followed closely by my Neco V2 which is a cracker with my O2 in third at the moment but it is too early to tell for sure yet.

 

[pinkfloydfan]

Quote:

 
silly question but have to ask.. maybe the batteries just need charging?

 
An obvious simple one but often overlooked so good advice

 

[CherryBomb]

Yes, I checked the battery.  It is definately a defective build.  

 

[jseaber]

There was a steep learning curve to achieving 99.5%+ yields with the O2. NwAvGuy uses several thin traces throughout the O2 PCB, which are prone to breaking when trimmed by certain lead clippers. That, and he's not joking about the extreme ESD sensitivity of the MOSFETS. You need ESD jackets, wristbands, work surfaces, proper tools, and a well devised cleaning process.
 
O2 is a tedious build, to say the least.
 
Quote:

Yes, I checked the battery.  It is definately a defective build.  

 

 

[shotgunshane]

I just placed my order with John and requested modified gain of 1.5x and 3x.

 

[PelPix]

Wouldn't you know it?  My O2 is getting here in less than 12 hours and my cat batted my wall wart straight onto the tile! 

 

[Br777]

Quote:

Wouldn't you know it?  My O2 is getting here in less than 12 hours and my cat batted my wall wart straight onto the tile! 

 
nothin a little scotch tape cant fix
 
 

 

[PelPix]

It fell 5 feet directly onto the plug and dislodged the mount on the plug, bent it at a 90 degree angle, and arguably damaged the internals.
I got the 16V 1A model, so it's like 5 pounds.  Guess I have to wait for a new one to ship!

 

[Willakan]

Quote:

There was a steep learning curve to achieving 99.5%+ yields with the O2. NwAvGuy uses several thin traces throughout the O2 PCB, which are prone to breaking when trimmed by certain lead clippers. That, and he's not joking about the extreme ESD sensitivity of the MOSFETS. You need ESD jackets, wristbands, work surfaces, proper tools, and a well devised cleaning process.
 
O2 is a tedious build, to say the least.

Which traces in particular are you talking about? I saw someone on DIYAudio talk about a pretty nasty failure condition whereby DC goes to both the DAC and the headphones if some of the traces for the PSU caps are damaged - but the good thing is that should be obvious in initial testing and is very unlikely to develop as a fault later.
As for the MOSFETS, I just never touched any part of them that wasn't plastic - probably for the best!

 

[Br777]

   So far so Great!
 

 

[liamstrain]

Quote:

Wouldn't you know it?  My O2 is getting here in less than 12 hours and my cat batted my wall wart straight onto the tile! 

Can you opamp roll that cat into a dog?

 

[maverickronin]

Quote:

   So far so Great!

Is that a custom cable on your LCD-2s or did your ES5s come in?