Marantz 2235 Headphone Hiss

[tlite]

Howdy all:

This is the same Marantz 2235 receiver I replaced transistors in back on this thread.

I'm getting a hiss from all input channels when listening through headphones. Even with nothing playing. Through the speakers all sounds fine.

In reading the service manual, I'm having a hard time determining what components might need replacement to remedy this. I'm guessing it's not part of the P800 board as I replaced all those. (Thanks again, @Steven Tate for the transistors!).

Any thoughts on what might be the problem here?

Thanks!

 

[txturbo]

I have seen this on many receivers.

This is a repost from a rebuild thread on a Sansui G-9000. I was trying to sort out why I had hiss. I think it really comes down to the resistors in the headphone circuit and the impedance of the headphones.

I have two sets of headphones, one Sony MDR-A1-DAC's with 24 ohm drivers and a pair of Sennheiser HD820's with 330 ohm drivers. I use the Sony's in passive mode.

With the Sony's it's dead silent now, before I could hear it no problem. With the Sennheiser's I can still hear it ever so slightly.

I can't see the noise with my scope and I can't measure it with my distortion meter.

So I decided to try out some of my other gear and see what it sounded like with the Sennheisers..
All tested on the Aux input with the volume at 0
On a scale of 1-10, 10 being clearly audible and 1 being dead silent..
Sansui G-9000 = 5 I would say it was at 15 before
McIntosh C33 = 1
McIntosh MR80 = 3
Pioneer SX-1280 = 7
Kenwood KR-9050 = 4
Revox B780 = 1
Fisher 500-C = 2
Marantz 4400 = 4
Marantz 18 = 4

So I think at this point I am chasing a ghost. Much of the difference may have to do with the individual headphone circuits. For example the G-9000 has 220 ohm resistors in line with the headphones, the Revox 470 ohm and the Pioneer 150 ohm.