fubar3
100+ Head-Fier
- Joined
- Jul 16, 2011
- Posts
- 249
- Likes
- 12
Legacy Sony MDR-V2 headphones still usable but padding fell apart so I bought Sennheiser HD238 phones which are a bassy disappointment. Hmmm, perhaps the 32-ohm headphone impedance needs a robust amp so I ordered the Fubar3/MK2 which specified:-
[size=10pt]Output Resistance:[/size]
[size=10pt]Extra low output resistance (Zo < 0.05 ohms),high current capacity 800mA per channel[/size]
Ha, that is a rediculous spec since the power supply is only rated for .5 amp. And I inspected the circuit boards. The phone jack is connected by a relay and 100 ohm series resistors to one little dual opamp OPA2604 which is good for 35mA into 600ohm. I could be mistaken since these are surface mounted boards with tiny SMDs but I found nothing to justify the spec. Also there is a slight smoky smell within. There are 4 relays and I think the headphone protect relay is always latched and running hot or "Fubared"
That said, it sounds fine to my unsophisticated ear, with the old Sony phones which seem to have a flat response. The HD238 phones are physically comfortable but tiresome with that mushy bass.
I emailed my concerns to http://www.audiophileproducts.com but they have not had time to reply.
[size=10pt]Output Resistance:[/size]
[size=10pt]Extra low output resistance (Zo < 0.05 ohms),high current capacity 800mA per channel[/size]
Ha, that is a rediculous spec since the power supply is only rated for .5 amp. And I inspected the circuit boards. The phone jack is connected by a relay and 100 ohm series resistors to one little dual opamp OPA2604 which is good for 35mA into 600ohm. I could be mistaken since these are surface mounted boards with tiny SMDs but I found nothing to justify the spec. Also there is a slight smoky smell within. There are 4 relays and I think the headphone protect relay is always latched and running hot or "Fubared"
That said, it sounds fine to my unsophisticated ear, with the old Sony phones which seem to have a flat response. The HD238 phones are physically comfortable but tiresome with that mushy bass.
I emailed my concerns to http://www.audiophileproducts.com but they have not had time to reply.
