WiiM Amp Streaming Amplifier Review

[martijn86]

Here is the sub out:

What's that? A third-order Linkwitz–Riley crossover??

 

[hashkey]

You sure you did not use Airplay with Roon?

That or Chromecast or Squeezelite… 'cause Roon Ready definitely isn't ready…

 

[VintageFlanker]

Dummy question regarding that load dependency issue here: Will its nature and amount (if any) be depending directly on the connected speaker set? In a way, that this issue could change/vanish with connecting a different speaker set?

Here are measurements, also with a real speaker load (channels charged with Boston CR8) :

 

[Golf]

Yes

So, pairing the WiiM Amp with 4-ohm speakers would make this issue practically non-existent?

 

[hashkey]

It's just an amazing bargain: DAC, Streamer, Bluetooth Receiver, 4 band EQ, and a 60 watt power amp for $300. Also looks really nice. Has a clean Bauhaus minimalistic "Apple made me" kind of look. For what it is, and what it costs not much of anything to complain about. Does it have a remote?

Yeah and it's Bluetooth which is a plus.

 

[Mnyb]

So, pairing the WiiM Amp with 4-ohm speakers would make this issue practically non-existent?

No its not that simple the 4 ohm curve is with a simple resistive load you will have to look at impedance curve of the speaker its case by case .

A "4 ohm" speaker can also have high impedance in the treble .

 

[hashkey]

I voted great because at that price it has no meaningful competition. I hope it's the start of something but WiiM's platform (even talking into account the app that looks like something off Android ten years ago) is going to take some beating.

 

[Mnyb]

Here are measurements, also with a real speaker load (channels charged with Boston CR8) :
View attachment 350958

So with the Boston speaker it's a very slight rise above 3k to 22k ( where i as old man does not hear anything anymore ) and its very sligth i would give it pass with this particular speaker the tiny bumps in tha bass would just disapear in the " room mud"

 

[Talisman]

So, pairing the WiiM Amp with 4-ohm speakers would make this issue practically non-existent

Be careful not to confuse the concept of nominal impedance of a speaker with the impedance curve. To know the actual interactions between speakers and amplifier you need to see the actual impedance curve of those speakers more or less between 5khz and 20khz. If indeed the real load of the speakers in that range is around 4 ohms constant then the problem with those speakers will be non-existent

 

[Brantome]

Only 4-band PEQ -> though there are whispers of more bands coming in future SW updates

Their latest roadmap update (10 Feb 24) says they’re working on 8 band PEQ and room correction for the Amp (and Pro/ Plus) as well as other stuff.

WiiM Amp Roadmap

Updated on Feb. 10th., 2024 What we're working on … We want to give you visibility into some of the features we are working on. Our official release notes have the complete list of released features. If you want to make a feature or pr...

faq.wiimhome.com

 

[Brantome]

reminder...
the same streaming functions and peq 4 bands" are necessarily available in their pro, pro plus..
;-)

And Mini

 

[DanielT]

Thanks for the test Amir. Very good features for little money. Pity with this load the dependency, as you and the other thread pointed out.

So, pairing the WiiM Amp with 4-ohm speakers would make this issue practically non-existent?

And with 6 Ohms, the FR should be pancake flat BUT stated Ohms are just an average given by the manufacturer. Example this JBL Studio 590 where JBL states that it is a 6 Ohm speaker. This is what it looks like in the higher frequencies with JBL Studio 590. So, how will the WiiM Amp FR be if it powers up a pair of JBL Studio 590 speakers?

JBL Studio 590 Speaker Review

This is a review, listening test and detailed measurements of the JBL Studio 590. I bought a pair last year on sale for US $800 but costs $999.95 each currently. This is a hefty speaker that even comes with (vibration absorbing) outriggers. I should definitely file for hazard pay for lifting...

audiosciencereview.com

 

[Golf]

Thanks for the test Amir. Very good features for little money. Pity with this load the dependency, as you and the other thread pointed out.


And with 6 Ohms, the FR should be pancake flat BUT stated Ohms are just an average given by the manufacturer. Example this JBL Studio 590 where JBL states that it is a 6 Ohm speaker. This is what it looks like in the higher frequencies with JBL Studio 590. So, how will the WiiM Amps FR be if it powers up a pair of JBL Studio 590 speakers?
View attachment 350961

JBL Studio 590 Speaker Review

This is a review, listening test and detailed measurements of the JBL Studio 590. I bought a pair last year on sale for US $800 but costs $999.95 each currently. This is a hefty speaker that even comes with (vibration absorbing) outriggers. I should definitely file for hazard pay for lifting...

audiosciencereview.com

All of which makes me wonder, if in real life this issue can be easily and effectively »un-eq’ed« at all.

 

[amirm]

@amirm you beat me on this (not hard, considering how late I am), I was about to finish my review.

Here is my data anyway:

I have been very late with this review myself.

Your measurements show the problems I saw in the first sample with rising distortion in low frequencies.

 

[Power Pop 23]

Am I correct in thinking the WiiM Amp will match well with impedance of the Polk Audio ES60 or not ?

 

[morillon]

And Mini

mini does not have chromecast...

 

[Brantome]

mini does not have chromecast...

Nor squeezelite, nor Roon, but it does have 4 band PEQ and other streaming functions…

 

[dominikz]

All of which makes me wonder, if in real life this issue can be easily and effectively »un-eq’ed« at all.

That depends on several things, but I agree it is not something an average user would be able to do.

However, the frequency response deviation added by the amplifier load-dependence will normally be <1dB with many loudspeakers, so not a huge factor - especially given that most loudspeakers deviate more than that across the audible spectrum (and usually even between two units of the same model).

For a while I was very invested in this topic because I have an integrated amplifier that is also very sensitive to load. After several tests I found it is not such a big issue from audibility perspective (link to post), even if measurements look pretty bad.
In these two posts I tried to explain in some depth how high output impedance / low damping factor in amplifiers causes frequency response deviations when loaded with real loudspeakers with their complex impedances: link to 1st post, link to 2nd post.

IMHO it would be very beneficial to include amplifier complex output impedance measurements to power amplifier reviews, as from those we can predict/calculate FR deviation for any known complex impedance load. This could then even be used to calculate EQ correction filters to compensate.
@amirm Do you think there's any chance to start including such measurements? I seem to remember you mentioned in one of the previous amp reviews you'd try to look into it. Thanks!

 

[Deleted member 48726]

Could you say how you could put together a starter hifi system with those features and performance for a similar amount of money? Genuinely curious.

That's not for me to say. But many cheap chip amps behave nicely. For example this one-->

3e audio TPA3255 260-2-29A Amplifier Review

This is a review and detailed measurements of the 3e audio 260-2-29A TPA3255 chip based stereo amplifier. It was sent to me by the company as a complete unit even though they only sell the amplifier modules. As you see, it is a generic box which is something you can easily build yourself. I...

www.audiosciencereview.com

There is no complex load that represents all speakers though.

In fairness, Amir has stated before in other threads;

"On Powercube, it doesn't like amps like this with high floating ground voltage on one channel. The cause is unknown."
"Also, there is a hardware bug in the Powercube load box where if the negative leg of amplifier output is at anything above 0, it will lock up and no longer function."


JSmith

True. But you can approach somethin akin to real loads. I like Erins approach even though his high impedance peak is a bit too low IMO. In the perfect world I'd like to see something like "typical 2 way 4 ohm" "typical 3 way 4 ohm" etc. -I acknowledge that testing would take longer time though.

 

[AudioSceptic]

This is a review and detailed measurements of the WiiM Amp streaming amplifier. It was sent to me by the company and costs US $299.
View attachment 350879
I was pleasantly surprised by the good bit of weight this small box has. It will help it not slide with the weight of the speaker wires and such. Back panel shows the differentiation from a regular amplifier:
View attachment 350880
With included streaming, you have a one box solution to play your content over the network. You can use the included Bluetooth remote or the application. The latter was rock solid which is more than I can say about some other (major) streaming amplifiers. It instantly found the device, upgraded its firmware and allowed reliable control of all function. I can't do justice to all of its capabilities in this performance related review but suffice it to say, it is very capable.

HDMI ARC allows a smart TV to feed the amplifier signal for content you play internally to your TV. A nice quality HDMI cable was provided (in addition to Toslink and even RCA) which was appreciated.

The only complaint I have is with similar looking subwoofer out. Looking from above, I thought that was the other input channel and spent good bit of time trying to figure out why I was only getting sound out of one channel. Having it be located elsewhere would help as opposed to being lined up with the left audio input channel.

Another nit is the rotary volume control not always acting on the volume. You would have to go two notches for example to change volume.

This review has taken a while to get out. The first sample I received performed well in most of the tests but showed quite an increase in distortion at lower frequencies. This manifested in Multitone test and power vs frequency sweeps. I ran the results by the company and they said this was an early production problem that was fixed. They sent me a new one which almost remedied that problem.

WiiM Amp Amplifier Review
With access to AP's APx516 analyzer, I was able to test the HDMI ARC on WiiM Amp:
View attachment 350882
This puts the amplifier comfortable above our average of all amplifiers tested:
View attachment 350883
View attachment 350884
For streaming, I wanted to use Roon but seems that is not there yet. Fortunately Chromecast is there which provides similar high performance streaming:
View attachment 350885
So no difference with respect to which digital input you use. Analog streaming in the first sample I tested was a bit worse with SINAD of 85 dB. The new sample degraded some with low frequency noise down to 80 dB (not shown). I assume this is not material to most users where analog input is only used for LP and such.

Cycling through inputs, here is dynamic range using Toslink:
View attachment 350887

Frequency response unfortunately shows the typical load dependency in lower cost class D amplifiers:
View attachment 350889

Here is the sub out:
View attachment 350892

As noted, multitone shows good performance now:
View attachment 350888

19 and 20 kHz intermodulation test shows the increased distortion there:
View attachment 350890

Crosstalk wasn't that great with analog input (inset) but very nice with digital:
View attachment 350891

Normally I sweep power with analog input but since digital is much better, I used that: [edit: "8 ohm" label is wrong in the first graph, should say 4 ohm).
View attachment 350893
View attachment 350894

Unless you use analog input, the gain settings is designed such that you never clip. This means that the "peak" power is the same as what I have measured above. Spec is 120 watts at 4 ohm and we are achieving that so no issue there. Same with 60 watt specified for 8 ohm.

Here is power sweep at different frequencies:
View attachment 350895
The graphs are well behaved for a class D amplifier. 20 Hz distortion though, rises good bit (dashed yellow).

Finally, the amplifier is stable on power up:
View attachment 350896

Conclusions
The WiiM Amp is a very well executed streaming, multi-room amplifier. It easily plays against big boys of streaming despite lacking their name recognition. Objective performance is very good for the class. The only wish is post output filter feedback to eliminate low dependency of the frequency response.

I am going to put the WiiM Amp amplifier on my recommended list.

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As always, questions, comments, recommendations, etc. are welcome.

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Analog streaming in the first sample I tested was a bit worse with SINAD of 85 dB.
Sorry about this but I have a tiny niggle here. It's not streaming with analogue is it? How can it be?