SnooP_WiggleS
Head-Fier
- Joined
- Jan 1, 2005
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I've got audio technica a500 headphones, which are low impedence (64ohm). So i thought i'd build an apheared 47 amp instead of a cmoy, since its made for low impedence headphones which the cmoy aint so good for. I don't have the time or money to build a pimeta (in particular the cost of the buf634's), and going off performance graphs cmoy is too compromising when used with low impedence phones. Current source is av-710, which provides enough plenty of volume, but I know I should be using an amp or buffer. I'm going off:
http://benfeist.com/a47/default.asp
However they use the uber expensive buf634 in the power circuit, and i'm building for a budget, so I've substituted an VPB opamp power circuit from tangeant, since a cheap 741 opamp can be used. Or can it?
http://tangentsoft.net/elec/vgrounds.html
To end up with the following circuit (only one of the two channels shown):
So now for the questions:
Any problems with changing the power circuit from the original?
With the given power circuit, how importent is the power supply choice?
Any problems with using this headphone amp (designed for 32ohm grados) with 64ohm audio technica?
The circuit doesn't have an output cap, so I should add one?
I'm guessing i should tie the input ground to -Ve of battery, and output ground to virtual ground?
Thanks for any help in advance
http://benfeist.com/a47/default.asp
However they use the uber expensive buf634 in the power circuit, and i'm building for a budget, so I've substituted an VPB opamp power circuit from tangeant, since a cheap 741 opamp can be used. Or can it?
http://tangentsoft.net/elec/vgrounds.html
To end up with the following circuit (only one of the two channels shown):
So now for the questions:
Any problems with changing the power circuit from the original?
With the given power circuit, how importent is the power supply choice?
Any problems with using this headphone amp (designed for 32ohm grados) with 64ohm audio technica?
The circuit doesn't have an output cap, so I should add one?
I'm guessing i should tie the input ground to -Ve of battery, and output ground to virtual ground?
Thanks for any help in advance