Axiom Home Page Forums General Discussion Home Theater anyone have XPA-1 amps?

If I remember correctly Randy did exchange components on his MPS-1 a number of times before giving up. A year or two later when I spoke with Lonnie he wouldn't even bother with replacing or exchanging anything, he simply suggested that the XPA-2 and the M80s were a mismatch and offered the suggestion of two XPA-1s to drive the M80s (at twice the price).

Jiminy Xmas.

I keep looking at the UPA-2 longingly, but all these reports make me nervous. I'm also nervous about the heat generated by the thing, since it's an AB, not a class D. Someday, maybe, someone will make an affordable (read, ridiculously cheap) class D stereo amp not based on ICE. I'm looking at you, Ian.

emotiva has the same 30 day return policy as axiom so perhaps you'd like to give them a try. i own both a UPA-2 and a XPA-5 mind you they are currently driving 8 ohm loads but neither one of them gets hot, in fact after watchine avatar at a good volume (not ear bleed) the XPA-5 was only slightly warm. when i first got the UPA-2, i did a test and ran my fronts off of it for about an hour and it barley got warm.

again, this was with 8 ohm loads. when i get my new front 3 from axiom i'll see how the XPA-5 will handle the 4 ohm loads combo'ed with two 8 ohm loads for 5 speakers running on it. i'll be sure to let you know if i see a real noticable temperature rise or not. i should also state that both of my amps are completely out in the open with free air on all sides nothing stacked on them and they are not enclosed in any way. if that helps.

It does help! Thank you!

I know this is going to sound like I'm an absolute idiot when t comes to electricity (which isn't far from the truth), but I'm just thinking outloud (well, typing out loud... No wait I'm... Oh nevermind) so bare with me...

Since heat is one of the main limiting factors when it comes to amps, and thermal shut-down, I'm just curious if it would be at all possible to create a 'liquid cooled' amplifier? Of course I don't mean submerging the amp in water, but merely creating an enclosed casing around the heat sink with some sort of circulating liquid to cool it down. So long as the liquid didn't touch anything but the heat sink, wouldn't that be possible?

I can understand that its probably cost prohibitive to design such a system, and the danger of the liquid escaping into the electical part of the amp has undesirable side-effects to say the least. I'm just wondering if any really high-end/high capasity amplifiers have ever incorporated this kind of cooling technology into their design, or if its simply impossible to combine liquid cooling with an electrical amplifier?

Again, I'm just thinking (typing) out loud, so don't laugh too hard if the notion is perposterous.

Micah,

You're not out in left field at all. It's done with computers all the time. I don't see why it couldn't be applied to audio amps, or the like.

My MPS-1, even after a 3 hour movie, is cooler than the pre-pro feeding it. It's a Class H amp, whatever that is.

Scott

Drippy...

It could go back even further than that. But once I found that article I stopped looking. It's been done. Wonder why it's use has been so limited though, and why we don't see any liquid cooled HT amps around? It seems to me it would greatly reduce the size/weight of an amplifier if they didn't have to employ such massive heatsinks to dissipate all that heat, and would also make for closer stacking of components as there wouldn't be a need for all that space around the amp to let the air in to cool it.

But I suppose they have their reasons. If it were indeed more efficient, somebody would be doing it.

Still gotta cool the radiator--the heat MUST go somewhere.

micah, often times the heat-sinks are NOT the majority of the weight, usually the heat sinks are aluminum fins, and with aluminum being light and a good conductor of heat, this is an idea metal to use... the majority of the weight of an amp is the power transformer.. next time your at lowes or home depot, go to the electrical isle and look for a transformer (you will see what i mean then)

as far as liquid cooled, you have to think about the market here... most of the liquid cooled pc's that i see are gaming pc's for guys that want to tinker, ect... most HT people want to plug their stuff up and go...

if you can keep the transistors cool, yes you can push them much harder, its called thermal breakdown... when they get to hot... just like your computer, the more you cool it, the faster you can make the processor run.... similar idea.


Right now i have Krell amps, and they are class A amps. so they do get Quite hot. i personally would not want a class D amp powering my main speakers, i guess im old fashion... but my amps cap out at 500W per channel.... Sounds like i would probably be better off getting an older Krell that will produce the power im looking for.....



Thanks for you inputs guys, i appreciate it.

What kind of amps did you say you had, again?