Sony stepped attenuator/foil resistors 4556 headphone amp modules

[cathodes]

Hi Chaps,

I have to offer two excellent high quality headphone amp modules with stepped attenuator - built using precision foil resistors!
Uses the well known 4556 headphone amp IC.
5 position rotary switch stepped attenuator in 6db staps: [Attenuations of 0db, 6db, 12db, 18db, 24db]
All foil resistors for excellent sound quality.
Ex very high quality Sony broadcast equipment from 1980's, when Sony very serious about audio quality.

Requires +/- 15V power supply and signal input - very easy to use, you can build in to an existing project for a headphones output.
A great way to make an excellent little headphone amp with little effort!

It could also be adapted to be used as a high quality active line or buffer amp. Of course you can experiment with changing the op-amp if desired.

Price is GBP15 each (well worth it for the foil resistors alone)
+ shipping UK GBP4.00, Europe GBP6.00, Outside Europe GBP8.00

Please PM if you'd like one (or both).
Two only, so be quick!
Cheers,
Rob

 

[cathodes]

Schematic for stepped attenuator headphone amp

I've attached a schematic so you can see exactly how it's designed.

 

[ej25awd]

Does the service manual indicate that they are actually foil resistors? To me these are likely SMD resistors with leads added. Fairly common on Japanese industrial electronics.

 

[00940]

If anyone wants to use these as headphones amp, it would be a good idea to change r152/252. 220 ohms is much too high as output resistors.

 

[cathodes]

Both modules now no longer available