[tonyptony]

So I got mine yesterday. This is an upgrade from my Ultra 550. As I noted in another thread my system is currently not in its normal state (preamp is out for a checkout), so I am running my Squeezebox analog outs directly into the amp (under volume control of course). A couple of questions.

Does the Double+ result in a change to the overall gain of the amp? I ask because I was surprised by how much I actually had to raise the Squeezebox volume to get a normal listening level. It was at about 90% (whatever that means). Unless it has some sort of weird exponential curve to it I would have thought going directly into an amp that normal listening levels would be reached with a lower input level.

How long (don't throw anything at me Frank!) should it take for the new output devices to break in? I figured even with the configuration I'm in I may as well get some good burn-in time built up.

[martyo]

I didn't notice any change in the gain.

The output devices don't require any break in  . With all my gear, while I wasn't listening for it or keeping records, seemed to my ears to "open up" after a couple hundred hours. That includes the "double" upgrade. I haven't noticed any change over time with the "+" upgrade. Since you asked the question I assume you have experienced this yourself at some point. We are talking subtle change here, like a tweak.

[tonyptony]

To be honest, to a lesser degree with Frank's amps than other amps I've owned. When I went from the EXR5 to the Ultra, apart from the obvious improvement in sound, over the first 100 or so hours it did "open up" as you say. I typically listen to a new piece of equipment intently and document my impressions only for about the first 10-20 hours, then I really don't pay attention to it until it's well past the 100 hour mark (I'm usually not even in the same room during this time). I've found over the decades that for me, at least, it's a good way to see if there really is any change from when I first get something.