[Tedro]

Quote:

Originally Posted by kklee /img/forum/go_quote.gif 1. Don't mount the power supply transformer in the β22 chassis, you'll end wasting weeks (and $$$) trying to resolve transformer hum and then end up moving it to an external chassis (and end up with lots of extra perforations in the bottom of the amp chassis).

 

[sachu]

Awesome! ^^

YOur impressions on it?..any of the hum that these folks are talking about?..using low impedance cans?

 

[MoodySteve]

^^^
I virtually guarantee it.

 

[Tedro]

Its silent, no hum, nothing. Even with 50 Ohm headphones. That is all.

 

[FallenAngel]

Quote:

Originally Posted by Tedro /img/forum/go_quote.gif Its silent, no hum, nothing. Even with 50 Ohm headphones. That is all.

Try it with a pair of Denon D2000/D5000 and you'll see.

 

[compuryan]

I can hear hum if I turn up the volume all the way with my HD650, but at around normal listening volumes the hum in completely inaudible.

 

[Tedro]

I only have one pair of headphones....

 

[johnwmclean]

One or two σ22’s to power a balanced rig for headphones only? I’ve heard a lot of ramblings and differing opinions, but nothing of real substance. Any benefits? Or is this purely an exercise in overkill and spectualation.

 

[TimmyMac]

Quote:

Originally Posted by johnwmclean /img/forum/go_quote.gif One or two σ22’s to power a balanced rig for headphones only? I’ve heard a lot of ramblings and differing opinions, but nothing of real substance. Any benefits? Or is this purely an exercise in overkill and spectualation.

amb says 1 PSU with a 100VA trafo is sufficient for headphones. He's the designer, so I'd probably take his advice. People use 2 so they can drive speakers, or so they have a true monoblock system. Really, though, don't worry about it.

 

[Tedro]

Quote:

Originally Posted by FallenAngel /img/forum/go_quote.gif Try it with a pair of Denon D2000/D5000 and you'll see.

PIF?

 

[naamanf]

One thing I have found is that TRS jacks cause a momentary short when pluging/unplugging them. I highly suggest having the amp powered off or outputs disconnected when plugging/unplugging the jacks.

 

[scompton]

Quote:

Originally Posted by naamanf /img/forum/go_quote.gif One thing I have found is that TRS jacks cause a momentary short when pluging/unplugging them. I highly suggest having the amp powered off or outputs disconnected when plugging/unplugging the jacks.

I seem to remember reading about one catching on fire at a meet when a hard to drive ortho was unplugged at a high setting on the pot.

 

[amb]

Yes, at the very least, the volume should be turned to minimum before inserting/removing the unbalanced TRS headphone plug. If the volume is not turned down, the momentary short on the plug can cause a very large current to flow from the L and R channels' output to each other or to ground, enough to cause damage to the amp (and the β22 could certainly deliver a huge amount of current).

 

[poo]

^ Is there another (safer or more practical) solution? I'm sure at some point either I or someone else who doesn't understand the relevance is going to unplug a pair of headphones...

 

[amb]

Just try to develop the habit of turning the volume down before you plug or unplug the headphones. It becomes second nature after a while. This is not just for the β22, but is a good thing to do in general.