ICEPower 125ASX2 Class D Amplifier Review

[ohskigod]

To you, or anyone else:

Have anyone take advantage of their on board analog meters to expose them on the case, like amp or Volt meters (it has both) ?

I mean I do use them to measure but only with the DMM till now, as sanity check.
But I have seen crazy simple stuff as industrial panel meters on them.

I know nothing about this. You mean the board has the capability for using analog meters?

 

[Sokel]

I know nothing about this. You mean the board has the capability for using analog meters?

Yes, that's what P106 connector is for, it's scaled down analog meters (two for each channel) .
It exposes output Voltage and Amperage, separately (both as Voltage-/+) as follows:

Edit: connector's pinout:

 

[Sokel]

I know nothing about this. You mean the board has the capability for using analog meters?

And talking about analog, it also reports temp this way (the highest of the ones it measures at several different spots) .

 

[ohskigod]

And talking about analog, it also reports temp this way (the highest of the ones it measures at several different spots) .

well I am definitely gonna explore this down the road, thanks

 

[Sokel]

well I am definitely gonna explore this down the road, thanks

We need an Arduino ninja to gather all that in one place, that would be really nice.

 

[Miercoles2022]

I retrofitted a 300A2 into a vintage chassis with big power meters a few years ago. The onboard Vmon pins weren't stout enough to move the OG meters much, but they indeed work.

 

[Sokel]

I retrofitted a 300A2 into a vintage chassis with big power meters a few years ago. The onboard Vmon pins weren't stout enough to move the OG meters much, but they indeed work.

300a2 voltage out of this pins is -/+5V while 1200as1/2 is -/+12V.
Some VU meters would need more juice, for sure.

 

[xaon60]

Hello,
I own an SMSL A8 integrated amplifier equipped with the 125ASX2 module. I’ve done some research, and according to the ICEpower website, it seems to be fully compatible with the older modules.

In your opinion, is there any benefit to upgrading it? My current module is the same as the one in the photo.

 

[SimonY]

Yes

 

[Scot]

Anyone know how the 125asx2 (current conductor revision) would/could handle a 3ohm load in btl. Was thinking about putting together a mono block setup for a Magnepan cc5 center, which is the worst combo of inefficient and hard to drive, though I think sounds nice and works with my nfr 645s. Specs seem to say 3ohm is beyond its limits.

(150hz-20k only if it matters, since the cc5 has basically no output below 150)

 

[Pajamas llama]

All these icepower amps suck at full frequency, and should only be used at lower frequency. And they call it 2x125 watts, which it never ever has. I've seen them be about ¼ of that as soon as you don't measure @ 4ohm, 1khz and 1%THD.
With regular 8ohm 20-20.000Hz and 0.05% THD they are about 35 watts at best. And in the test even with 4ohm it was only 96 watts. And I'm sure it's even lower in countries with just 50hz AC outlets since coils work better with higher frequency. You usually see a 10-15% watt drop in same amplifiers as soon as they are plugged into 50hz, but still manufacture claim same watt without beefing up the PSU.

 

[Scot]

While I went a different direction, I’m not big on “I’ve seen” being a reference. While what you said may have merit, could you please post more information and reference on the tests you have seen?

Who did the testing, on what equipment? More specific results. Which version of the boards, that kind of thing.

 

[Pajamas llama]

While I went a different direction, I’m not big on “I’ve seen” being a reference. While what you said may have merit, could you please post more information and reference on the tests you have seen?

Who did the testing, on what equipment? More specific results. Which version of the boards, that kind of thing.

If you just dig deep into their own specifications they'll drop to about 35 watt per channel as soon as it's measured with full 20-20.000hz, 8ohm and 0.05% THD.
I think it's "funny" how almost every class D amp all of the sudden is measured with 20x higher distortion, like that's no big deal.
The worst thing is subwoofers where they'll claim 2000 watt etc. Sometimes those THD numbers will be as high as 10% so 200x the normal distortion. But they don't specify how those 2000 watt was measured unless you dig deep yourself. And of course measured at 2 or (most of the time) 4 ohm, which a subwoofer driver never is. Some reach 120 ohm close to fs, and that's when the driver is cold. As soon as you play, the temperature rises and ohm rises.
Unfortunately they can claim about anything, because there's no penalty for lying. No HI-FI police. Take Piega. High end Schweiz company. Their 3rd most expensive speakers (50-60.000 USD a pair) was actually 10 dB lower sensitivity than specified. And with amps it's even harder to know because most people don't have the equipment to test. You might think something is off if your amp only gives ⅛ the power specified, but if it only delivers 50-75% you'll probably never know for sure, since most people will not unplug their amp and send it for testing and pay for that.

 

[Scot]

Except their specs are very clear. It is 20-20k 120w on 4ohm at 1%. This isn’t similar to the bs claim many have made back in the day, with no details. Common to say 2000w amp! But that’s at one specific frequency and resistance, with 90 percent distortion.

Now clearly the statement about 120w is at 4ohm;8ohm is 58w for the same full output. Which makes sense as a doubling of power for a well designed amp.

Check out YouTube for some guys who make a ton of videos or checking out old school and new school amps. You can also read armin’s tests here for specific results on the older, supposedly less capable version.

I’m sure you have very strong beliefs, but evidence is where we need to be. Please go get some specific reports and details backing up your claims and that run counter to the evidence presented in this thread already.

 

[Pajamas llama]

Except their specs are very clear. It is 20-20k 120w on 4ohm at 1%. This isn’t similar to the bs claim many have made back in the day, with no details. Common to say 2000w amp! But that’s at one specific frequency and resistance, with 90 percent distortion.

Now clearly the statement about 120w is at 4ohm;8ohm is 58w for the same full output. Which makes sense as a doubling of power for a well designed amp.

Check out YouTube for some guys who make a ton of videos or checking out old school and new school amps. You can also read armin’s tests here for specific results on the older, supposedly less capable version.

I’m sure you have very strong beliefs, but evidence is where we need to be. Please go get some specific reports and details backing up your claims and that run counter to the evidence presented in this thread already.

I have read plenty of test, and icepower never perform well with full range. I'm talking about their own claim if you look into the specs, it's spec'ed @and 1 kHz. It's been probably two years years since I last checked, and there it was spec'ed @ 1 KHz. But it's "funny" how normal standard is @ 0.05% THD, but with 95% of the class D amps it's all of the sudden @ 1% THD and at the same time claiming how clean and undistorted these amps are.

 

[mdsimon2]

Have you looked at their very detailed datasheet (https://shop.icepoweraudio.com/wp-content/uploads/2023/02/ICEpower125ASX2_Datasheet_2.4.pdf) which does a great job of characterizing performance instead of blindly looking at the headline specs?

Michael

 

[Pajamas llama]

I don't know what SE mode is, but I guess it's definitely not the standard mode

 

[Matias]

@Pajamas llama Please read these 2 threads below to get up to speed.

Class D FAQ

This topic is dedicated to Frequently Asked Questions about class D amplifiers. If you have been directed here the reason is that it is easier to concentrate the frequent answers here instead of repeating them in several topics. Q1: Class D power ratings cannot be true. How can these small and...

www.audiosciencereview.com

ICEpower Conductor

New tech from ICEpower announced. The prototype is already around SINAD 102 (1kHz 5W into 4 ohms) with ~300W (1% THD+N of 1kHz into 4 ohms) and no rise around the knee. And with 6.67 kHz riding along with the 1 kHz, the old limitations of HCOM seem to have been solved...

www.audiosciencereview.com

 

[quattro98]

Anyone know how the 125asx2 (current conductor revision) would/could handle a 3ohm load in btl. Was thinking about putting together a mono block setup for a Magnepan cc5 center, which is the worst combo of inefficient and hard to drive, though I think sounds nice and works with my nfr 645s. Specs seem to say 3ohm is beyond its limits.

(150hz-20k only if it matters, since the cc5 has basically no output below 150)

Yes. 3 ohm min impedance for BTL is listed on page 11 of the spec sheet linked by mdsimon2.

Interestingly it also lists 3 ohm for SE, but notes "The amplifier can be loaded asymmetrically. One channel can be loaded with minimum 2 ohm. The other channel must then be minimum 6 ohm.