[vapman]

Lately in several different threads I've seen more and more people posting about powering their headphones from the speaker jacks on the backs of their older stereo receivers.  I remember doing this about 10 years ago with some SR-60 and an NAD 3150. it blew my mind, i've never heard that much bass out of Grados before!
 
I haven't done it since but I'm interested again with the recent surge of interest in this method of headphone amping.
 
Anyone else doing it, any tricks, tips, whatever?

 

[MrCurwen]

Many headphone outputs have a series resistance added, a 100 ohm resistor or such. This raises the output impedance significantly, messing up the frequency and transient response. I can understand this trend you're describing.
 
My main thing is headphones, but every amp I have (all DIY) must also be able to drive speakers on occasion, even if at modest volume.
 
So I connect both speakers and headphones at the same 4 ohm tap at the OT secondary. Since the primary side is fed with a low impedance as well, the setup provides a very low output impedance. This has the effect of improving transient response, and flattening the frequency response. Bass control is the biggest winner, just as you describe.

 

[CrocCap]

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