IcePower 250 ASP - First stereo review


2013-05-10 4:11 pm
Out of 3 modules ordered I managed to get 2 working. I could probably get a third but I expect to be returning them.

Anyway, what is working is a pair of them. I usually listen to Parasound Halo A23's connected to my DIY monitors which use Mundorf AMT tweeters and ScanSpeak Revelator woofers. Capacitors are Clarity MR in the tweeter, ESA in secondary locations.

So far I can't tell an audible difference between these two amplifiers. I was actually hoping to get great imaging, or something like that but at least in this case the ICEPower sound identical to the A23's. The A23's are class A to about 20 watts, which is probably 95% of where I listen anyway. The AMT's tend to be purely resistive, so a relatively easy load compared to the normal tweeters.

I am feeling a weird sort of headachey thing, but that's probably more to do with dental work than the amplifiers.

I'm afraid I have nothing really to report at this time. Tomorrow if I have the time I'll do some real A/B testing. However in terms of if some one stole my A23's and replaced them in the middle of the night with the ICEPower I would have to say I'd be unable to tell the difference so far.


The amps have been playing for 24 hours now, movies and music. My opinion remains the same, as neutral and colorless as the Parasound Halo's. My very young not-so-much-a-volunteer said they sounded more "dynamic" and expressive. I could not tell.


Can you kindly help with the wiring connection for the amps. How and where are the power and balanced/unbalanced inputs connected and the out pots connected to? I am not planning on getting a case, hence the questions.

Thanks and Regards
Hi Erik, sorry to resurrect an old thread. There is surprisingly little information and reviews, builds on these PE icepower asp modules. Was wondering about your longer term impressions.
I'm. Planning to use the 500asp and 500a for multiple subwoofer amps. So I'm interested in their bass performance, if you have any findings. Thanks!
Iam not Eric, but the ICE power modules are just perfect amps.
For sub woofer use well suited, maybe even to good. They have a very high damping factor. Only problem, if you plan to use them for long periods of highest output, like very small woofers with Linkwitz transformation or a lot of EQ, you have to take care of cooling.
Not only the heat sink has to be enlarged or coupled to an aluminum case, but also the components on the board need cooling. A slow running, inaudible fan is a good idea to keep the air moving.
See, even at 90% efficiency, the remaining 10% may be 50 Watt with this amp. Heat up your 50 W soldering iron and you know that this is quite some heat. A part of this is lost in the inductors, which are only air cooled, not connected to the heat sink.
Hi Turbowatch2,

Thank you for your quick reply! That was the reason i was attracted to them, low output impedance of 5miliohm, and high current limit of 35amps. Conceptually both of these are very important for good subwoofer amp, although sometimes it is still a mystery, how amps good vs weak bass.
Maybe a bit of off topic, but i'm hoping these would be an improvement over my current sub amp, which are a crown XLS and an old QSC RMX2450. Both are no slouch, so i'm somewhat hesitant.. I'm hoping to get performance close to the best sub amps, speakerpower or Lab gruppen type sound. Though most of these claims are all subjective impressions. Measurements wise, the XLS and inukes deliver the power, but subjectively somehow there is a difference, according to some of the most demanding and discerning bass nuts out there.

Another consideration is that the 500ASP and 500A are the older ICEPOWER models. Since i'm using for subs, i'm not so concerned, as i suspect the improvements in the later models are more on mid and highs transparency etc.

All the above is a load of bull if one takes the position that all amps that measure the same sound the same... but in absence of perfect info, we have to base our decisions on something...

i won't be running aggressive LT boosts or anything, and i do intend to get good mounting on the heatsinks to the aluminium enclosures. Part of the reason i'm ditching the QSC is the noisy fan, despite a fan mod, so i'm hesitant for fans..

Thanks again!
if you talk about fan noise, you used the wrong fans, had them run too fast or did not adjust them right.
There are very good fans out there, cheap and made for permanent use in computers.
You can get them with a temperature sensor (good for heat sink´s) or add a simple, 1$ adjustable voltage regulator like this one: LM317 DC-DC Converter Buck Power Module Adjustable Linear Regulator 35.6*16.8mm | eBay

The larger the fan is, the slower it will run. If you take a 80x80mm fan and such a regulator set to about 8-9 volt, you will see the fan move and push air, right in front of you, but not hear it. If you use it in an amp, usually there will be some sound level, so even if you may be able to hear it in total silence, in real live you can not tell if it´s running.

Last, good high performance fans have ball bearings, but these are loud. There are silent fans for computer use that have sleeve bearings with an oil reservoir, these are the most silent ones, while having a very long live.
I like "Arctic" fans, they are no frills, well build, very affordable and silent. Depends on your location what brand you may find best. Maybe try a few.
If you use a totally closed aluminum case for your amp that is not too small (small looks cute, but technically it is not the best), you may put a fan inside. The moving air prevents the build up of hot spots and distributes the heat over the case. This way you do not have noise and dust problems, like with a PA amp that suffers more from permanent use in a living room than from a live concert once a week.

The sound of amps is something that was considered "solved" around 1980, when the necessary parts where available cheap. From that time on, any talented developer could build a perfect amp, if not limited by extreme cost decisions. Real "better sounding amps" where mostly sales talk. Worse sounding used too cheap parts, not suited for audio.
A top of the list 1985 amp will sound similar to any good amp of our days. The so called "sound" is not a matter of the amp, but how it interacts with the speaker. Some amps fit better or are more stable on a certain loudspeaker than another. This explains why some folks are fanatic about single driver, broad band speakers. Almost any decent, cheap amp will sound fantastic with such easy to drive load. A really good, expensive build amp may not show any real advantage in such an situation.
So the conclusion from this side may be "all amps sound the same", which mostly owners of cheap amps aggressively promote.

The ICE amp sure is a perfect amp, for any application. IMO there are no amps that really sound better than perfect. So how can you find any better amp? Final amps are the worst that can happen to a producer of amps or amp modules, like Hypex. Once sold to a customer, the customer never returns. So sales talk will always "invent" and market better amps the developers can´t. The buyer of such a "new" amp has to find advantages or admit he got fooled. So, presto, there is the "better sounding" amp.
Something that I find really remarkable, really cheap chip amps, most D-class, can sound as perfect as my older, expensive amps. Of course, the smaller ones have limits driving huge speakers or heavy sub cones, but the general "sound" is often just as perfect and for example, another CD-player, may show more differences than changing the amp.

The real advantage of D-amps is the limited use of energy. This is what makes them better than old high end amps. just my personal opinion, which is subjective, as always.