[jscivias]

Thanks guys for the feedback. I tried using my iPod as an input rather than my laptop/USB, and I find the sound to be less harsh.. did I bypass the PanAm DAC by using the iPod?
 
also, I'm currently using a cheap USB cable to connect my laptop to the PanAm, do you think that using higher end cables makes any difference? I thought that a USB cable is digital so it shouldn't really matter much.. eh, I don't know. 
 
p.s.  I've also tried Westone 4 with the PanAm and I prefer this pairing more than the DT880, I guess my ears are just partial to the warmer sound.. although I really bought this to drive DT880. it's growing on me though, I like it much better than my first listen. 

 

[palchiu]

My PassPort is near death, any suggest?
 
Replace battery in PassPort or external power-pack.
 
Thanks!

 

[ahhui90]

how long have you been using it?

 

[palchiu]

  how long have you been using it?

 
It since Sep. Last year, atleast used them five days a week.

 

[ahhui90]

   
It since Sep. Last year, atleast used them five days a week.

http://www.head-fi.org/t/626204/alo-pan-am-desktop-portable-headphone-amp-dac-impressions-and-reviews/270#post_9612036
 
I might want to try this out.

 

[palchiu]

The battery is complete dead and removed, I'm looking for similar size can fit in the PassPort.
 
Here's some pics if someone interested.
 

 

 

 
PS: Battery still good. Only dead the battery protect board.

 

[ahhui90]

Wow that's interesting. I see 3 silver stacks of cells, so total capacity is 9000mAh I guess.
Just for your info, I have bought and currently using anker battery pack I mentioned a few posts back, it works at a fraction of the price of Passport.
Gonna try to make a short DC power supply interconnect, somewhat like this: http://www.ebay.com/itm/2x-Short-DC-4-0x1-7-Male-Plug-Right-Angle-Cord-to-5-5x2-1-Male-Conversion-Cable/291020367884?_trksid=p2047675.m1850&_trkparms=aid%3D222002%26algo%3DSIC.FIT%26ao%3D1%26asc%3D19219%26meid%3D2899083644830518240%26pid%3D100011%26prg%3D8681%26rk%3D3%26rkt%3D5%26sd%3D300995072674%26

 

[palchiu]

It's series connecting config, 3X3.7V to 11.1V(3000mAh)
 
506085 3.7V
 
Maybe Optima Batteries will be a good option for PanAm.

 

[NZheadcase]

  The battery is complete dead and removed, I'm looking for similar size can fit in the PassPort.
 
Here's some pics if someone interested.
 
 
 
PS: Battery still good. Only dead the battery protect board.

 
Have you hit up Alo about a replacement protect board? I mean if the batteries are still good, it might pay to send an email their way.

 

[palchiu]

   
Have you hit up Alo about a replacement protect board? I mean if the batteries are still good, it might pay to send an email their way.

They're out of warranty already.

 
 
I'm not in US, shipment may let me get many boards to replace...

 

[supersonic13]

Hi Pan Am owners, I'm looking to get some feedback on a problem I've encountered. I picked up a Pan Am (with Passport battery) and some Sennheiser HD650s during Black Friday as my first real setup, but I've only gotten around to playing around with the two for an extended period of time tonight. The sound is amazing, but I've noticed an odd noise that occasionally occurs and I believe that it is caused by the Pan Am. My current setup is computer->USB->Pan Am->HD650s.
 
Every once in awhile I hear an odd distortion/interference type noise, the best way I can describe it is usually a high pitched electronic sound (played through the headphone). The sound is not constant and the tone can vary slightly as it is occurring, it can also vary in volume and in duration. It happens intermittently and I have been unable to find anything in particular that causes it to happen, position of the volume knob seems to have no influence on it. I first noticed the noise when I had the HD650's on my head with the Pan Am on, but I wasn't playing any music at the time. Having heard that, I started paying closer attention as I was listening and found that it could also occur while a song is on. I think that the problem is coming from the Pan Am, as one time I was quick enough to take the USB cable out of the Pan Am while I heard the sound, yet the sound persisted for another 2-3 seconds without any connection to a source.
 
I have plugged the HD650's directly into my computer, which can drive them to an extent (albeit poorly), and have never heard the same noise so I do not think that they are the problem. I do not sense any problems (a blown driver, etc.) while listening to music normally through the Pan Am when this sound is not being produced. The problem persists with both the stock tubes and the extra pair I purchased to mess around with and have tried switching both sets multiple times with no luck. Initially I thought it might be interference caused by my computer as they were very close together, so I moved them about a foot apart and still have the same problem. Should I attempt to space them out even further? Has anyone had problems with a Pan Am and electronic interference? Has anyone had any kind of similar problem or have an idea what might be the cause? I would appreciate any help, thanks in advance.
 
Edit: The same problem occurred when I experimented with my HD25's and the Pan Am, so I'd say that completely eliminates the HD650's as the problem.

 

[GarySaville]

Do you have the caps covering the tubes? I suggest you use them. With my setup, the PanAm is quite susceptible to EMI fields since it is close to my computer and various electronics on my desk. However, unplugging it during use and leaving the covers over the tubes helps reduce, if not completely eliminate, buzzing EMI type interference. 

 

[supersonic13]

  Do you have the caps covering the tubes? I suggest you use them. With my setup, the PanAm is quite susceptible to EMI fields since it is close to my computer and various electronics on my desk. However, unplugging it during use and leaving the covers over the tubes helps reduce, if not completely eliminate, buzzing EMI type interference. 

Good call, I was not using the tube covers earlier. I now have the covers on the Pan Am, but unfortunately the problem persists. This seems to have reduced the frequency of the distortion/interference a little bit, but it still happens approximately once every 15 minutes or so. It was a good idea though and I think it has likely narrowed down the issue to electronic interference. Out of curiosity, do you happen to know if EMI has a greater effect on tube amps than solid states?
 
I may attempt to rearrange my desk tomorrow in the hopes that adding a little more distance between the Pan Am and my computer will further mitigate the problem, but the distance will probably only be about 2 feet max and I'm not sure that will be enough to eliminate the problem. Did you end up trying anything else to help reduce your own problem? Any other ideas on things I can do to mitigate the problem? Again, I really appreciate the help.

 

[GarySaville]

 
Good call, I was not using the tube covers earlier. I now have the covers on the Pan Am, but unfortunately the problem persists. This seems to have reduced the frequency of the distortion/interference a little bit, but it still happens approximately once every 15 minutes or so. It was a good idea though and I think it has likely narrowed down the issue to electronic interference. Out of curiosity, do you happen to know if EMI has a greater effect on tube amps than solid states?
 
I may attempt to rearrange my desk tomorrow in the hopes that adding a little more distance between the Pan Am and my computer will further mitigate the problem, but the distance will probably only be about 2 feet max and I'm not sure that will be enough to eliminate the problem. Did you end up trying anything else to help reduce your own problem? Any other ideas on things I can do to mitigate the problem? Again, I really appreciate the help.

When I first got the PanAm, I did have issues with interference. But, now I do not, and I'm not sure what exactly fixed my issues since my desk is a complete disaster. I have DJ equipment, studio monitors, iPads, an iPod, iPhone, and midi gear surrounding me which all likely contribute to noise. What I have changed, is adding an iFi iUSB, as well as higher quality (more shielded) USB cables throughout my rig, and I shifted gear around until I found a sweet-spot for the PanAm. I also used to have a wireless router on my desk, and I switched to a wired router. 
Unfortunately, most of these changes happened slowly over the past year or so, and I'm not sure exactly when the interference disappeared. The same noise would also warble out of my KRK V4 studio monitors, but it does not occur anymore.
I would guess that wireless tech would be the most likely culprit, so the heavy data-flow from wireless internet would be the first thing I would look into. Then check out beefier USB cables. I'm not recommending ridiculously expensive audiophile USB cables, just cables with heavier insulation.  

 

[NZheadcase]

  Hi Pan Am owners, I'm looking to get some feedback on a problem I've encountered. I picked up a Pan Am (with Passport battery) and some Sennheiser HD650s during Black Friday as my first real setup, but I've only gotten around to playing around with the two for an extended period of time tonight. The sound is amazing, but I've noticed an odd noise that occasionally occurs and I believe that it is caused by the Pan Am. My current setup is computer->USB->Pan Am->HD650s.
 
Every once in awhile I hear an odd distortion/interference type noise, the best way I can describe it is usually a high pitched electronic sound (played through the headphone). The sound is not constant and the tone can vary slightly as it is occurring, it can also vary in volume and in duration. It happens intermittently and I have been unable to find anything in particular that causes it to happen, position of the volume knob seems to have no influence on it. 

 
This happens to me occasionally on the Macbook when using the PanAm USB cable that shipped with the PanAm. I replaced it with a cheapie USB and away it went. When using my Sony VAIO PC though, the PanAm USB cable has never made that noise. I also found that the PanAm sometimes won't get recognized by the Mac when using the PanAm USB cable. Weird, I know, but try swapping the cable.
 
Also, please try the following: 
 
1. Check to see if any of the other inputs give you the same issue. 
2. If you use the wall wart, try a different wall socket.
3. If you have either the Passport try it on battery power only, and not plugged into the wall wart.
4. Try a different set of tubes. 
 
Good luck on the troubleshooting.