Mono blocks that can provide that golden sound...

I also have a pair of XA160.5s. I agree they take some warm up time to sound
their best. I turn mine on about 2 hours before I plan to listen. Usually
before I start cooking dinner. When I am finished with the dishes, I go and
listen to music. During the winter and on weekends when I plan to do a lot of
listening, I turn them on Friday afternoon and turn them off late Sunday
night.

I think you should be able to find an acceptable balance somewhere between
leaving them on 24/7 and listening right after turning them on ie. with no
warm up. I turn off the radiators in my listening room during the winter, so
the extra I spend on electricity, I save on natural gas. Or so I tell myself. My
electric bill went up about $40 a month with the XA160.5. Heating the
listening room costs slightly more. I consider the increased electric bill well
worth it for the sound they provide.

There is a lot of discussion about these amps and the heat they give off
during the summer. And how environmentally unfriendly they are. So is an
SUV. We make our choices.

There should be other great amps out there, and some SS amps that aren't
class A. It could be fun trying to find some that you enjoy as much as the
XA.5s. Let us know what you find. I'm sorry I can't make any
recommendations.

Scratch that. Have you heard the Pass X.5 series? Less class A, less heat.

In that price range, I would recommend either the:

110 wpc Lamm M1.2 reference hybrid full Class "A" monoblocks.

or

220 wpc Lamm M2.2 hybrid Class "A/AB" monoblocks, (which are heavily biased into Class "A". (The first 41 wpc are biased into Class "A", and then they go into Class "AB".)

These hybrid amps sound very similar, with the M1.2 reference sounding just a bit sweeter in the mid-range, (as you'd expect from a full Class "A" amp). The M1.2 will drive most speakers with average impedance and/or efficiency, whereas the M2.2 has enough power to drive virtually any speaker. The sound is fairly neutral, with just a touch of tube sound in the mid-range. (They have a great bass response, and the treble response is very refined and well extended.) These amps will warm up fairly quickly. Upon startup, they sound good. Within half an hour they sound very good, and after an hour, or so, they sound great.

However, to get the best sound out of them, you will need to replace the stock Sovtek tubes with some sort of NOS tube. (Something like the Amperex Orange Globe 6DJ8, for less than $100 a pair, will make them sound very, very good. However, something like the Amperex Pinched Waist 6922's will take them to their ultimate sound quality, but they are fairly expensive, at a few hundred dollars a pair.)

FYI: I have two friends that own the M2.2 amps, and I own the 200 wpc M2.1, the predecessor to the M2.2. We have all owned Lamm amps for several years, and none of us has left the Lamm family of amps since we bought them.

Good Luck in your search.

How about using a programmable timer?

I think warm-up time is a constant for any piece of equipment. One or two hours is relatively short compared to other solid state amplifiers. I had the X.5 series, and those required 6-8 hours, and really sounded their best after 12-24 hours. The XA.5 is considerably less dependent upon time for me. Even tubed equipment can benefit from 1-2 hours.

I would recommend the Tripoint Troy, which is an external grounding system for all your components. You will not complain of your system sounding 2D, flat, and non-engaging. This is precisely the effect it has. Your system will sound great at start-up, it will only get better after that hour.

With all the care required for quality connectors and power, I would not use a timer.

while a step back, the mac 501s provide very good sound with no warmup. i had the xa60.5s, which were better, but not much. 501s have less transparency, top end extension, or microdetail retrieval. but again, not much. the immediate gratification of instant good-enough sound and not having schwetty balls while listening in houston in july tipped the decision for me.