2015 - Sony PHA - 1A Portable Hi-Res DAC/Headphone Amplifier
Jun 21, 2016 at 5:28 PM Post #378 of 430
Well it finally arrived after a near three week wait and endless false starts.It was a very modest £90 odd pounds including fed ex, how marvelous it must be to be the world's only retailer and think a price out of the sky. Treat this micro b -b interconnect like gossamer thread, never take it out of your house, be ultra observant that the connection side is in free space at the side of your bed, and cushion it on a soft bed of bubble wrap when in storage, or you will suffer the same fate.
 
Jul 6, 2016 at 6:59 AM Post #379 of 430
I have found that the oppo ha 2 implemented the same tpa6120 headphone amplifier as the pha 1a but oppo stated that its oppo ha 2 has an output impedance of 0.5 ohm. However, the tpa6120 is known to be having an output impedance of approx 10 ohm. So what is the actual output impedance on pha 1a?
 
Jul 6, 2016 at 7:44 AM Post #380 of 430
I have found that the oppo ha 2 implemented the same tpa6120 headphone amplifier as the pha 1a but oppo stated that its oppo ha 2 has an output impedance of 0.5 ohm. However, the tpa6120 is known to be having an output impedance of approx 10 ohm. So what is the actual output impedance on pha 1a?
Specification sheet on my PHA-1 said 10 ohms, then the on line version deleted that line from the specs. I think it is 10 ohms on the PHA-1 as well.
 
Jul 6, 2016 at 8:59 AM Post #381 of 430
Then how can oppo ha 2 be made to have an output impedance of 0.5 ohm when they both have the same tpa6120? What kind of magic oppo has XD
 
Jul 6, 2016 at 10:04 AM Post #382 of 430
Specification sheet on my PHA-1 said 10 ohms, then the on line version deleted that line from the specs. I think it is 10 ohms on the PHA-1 as well.

 


Just checked... the Sony PHA-1 is stated by Sony to have that same "High slew rate Texas Instrument TPA6120 headphone amplifier" as does the PHA-1A. Hence, same output impedance.
 
Jul 6, 2016 at 12:39 PM Post #383 of 430
Well oppo ha 2 implement the same headphone amplifier chip. how it can have an output impedance of 0.5 ohm? It doesn't make sense imo. Can anyone explain about the output stage difference in oppo ha 2 n sony pha 1a?
 
Jul 6, 2016 at 3:46 PM Post #384 of 430
Well oppo ha 2 implement the same headphone amplifier chip. how it can have an output impedance of 0.5 ohm? It doesn't make sense imo. Can anyone explain about the output stage difference in oppo ha 2 n sony pha 1a?

 

I would imagine that any amplifier design could put additional circuitry between the amp output and the headphone input, e.g., equalization, transformer, another amp stage, a resistive divider, all of which could change the final output impedance. But I think that would be very unusual, particularly if they point to that particular device as their amp.
 
Aug 22, 2016 at 8:56 AM Post #385 of 430
Is anyone listening to pha 1a while it is inside a case or pouch? I tried to put it into a gadget pouch and listen but it get warmed up pretty hot. Should I continue to do so or leave it outside of an open air environment?
 
Aug 29, 2016 at 11:07 PM Post #387 of 430
Is anyone listening to pha 1a while it is inside a case or pouch? I tried to put it into a gadget pouch and listen but it get warmed up pretty hot. Should I continue to do so or leave it outside of an open air environment?


I assume it needs to be out in the open, it's steel frame conducts even ambient temperature. Would be nice to have a case for it though, as it gets easily scratched and dented
 
Dec 10, 2016 at 5:02 PM Post #389 of 430
Picked up a mint condition PHA-1A off Amazon for 210, to compare w/ my HA-2SE...and whoa...I didn't think I'd actually like it better than the Oppo.  Sound isn't quite as warm, which matches up pretty well w/ my M100, H6 v2 and H7 headphones.  The clarity is insane and it really does a damn good job enhancing all of the aspects of the sound.  Using it with my OnePlus 3T currently and wow.  

Really impressed.  Definitely would have paid 300 for it, but even better at just over 200.
 
Jan 10, 2017 at 4:46 PM Post #390 of 430
If anyone wants the original cable for connect the PHA-1A to a Sony Walkman I'm selling one in mint condition in the "For Sale" forum. Thanks!
 

Users who are viewing this thread

Back
Top