Is Wiim Amp Ultra upgrade over Yamaha AS701?

[dankandi]

Hello audiophiles, i am using Yamaha AS701 for many years, and looking for something smaller and modern.

This is review of AS801 with similar audio circuit to AS701, with measurements.

Yamaha A-S801 Integrated Amplifier Review

The Yamaha A-S801 is an honestly rated 100 watt/ch integrated amplifier with a built in high resolution USB-B DAC to power a serious dedicated two-channel or upscale PC system with pristine fidelity.

www.audioholics.com

I tried one highly rated Chinese Class D amp, the O-NOORUS D3 PRO, with SINAD 90. But it was quite disappointing on 48V 5A GAN power supply.
It sounded more bassy excited but lacks the wide sound stage of AS701. I do not have measuring equipment but i played D3 Pro and AS701 up to their max tolerable volume, and i feel AS701 have more room left to go louder.

It is catch-22 AS701 gets abit fatiguing over time, i think the PSU cannot take the long play time stress.

But the D3 Pro is too dark.

Is Wiim Amp Ultra with dual TPA3255 gives me a nice middle ground? Thank you!

This is a teardown photo i found of WAU and D3 Pro

 

[DazST]

Welcome to the forums. I replaced a Yamaha as501 with a WiiM amp ultra for similar reasons, i.e. size and ease of use (especially for others in my house). I love the yammi and its now doing its thing in my office system, but in no way has the amp ultra been a step down and it has plenty of power for my needs. I'd be curious why you find your as701 fatiguing though; to me that suggests it could be your speakers rather than the amp.
I hope that is of some help.

 

[Fernandodelae]

I believe you have a really decent Amp there, I would get an Ultra (not Amp Ultra) and try all the possible connections to see which delivers best SQ. I agree with DazSt, if you find the present sound fatiguing that would be the speakers to blame or probably the play source, not the Amp. And it would probably be easy to correct via Tone controls or Room Correction & EQ (if you get the Ultra streamer).

 

[DazST]

I believe you have a really decent Amp there, I would get an Ultra (not Amp Ultra) and try all the possible connections to see which delivers best SQ. I agree with DazSt, if you find the present sound fatiguing that would be the speakers to blame or probably the play source, not the Amp. And it would probably be easy to correct via Tone controls or Room Correction & EQ (if you get the Ultra streamer).

I agree that's a good suggestion. I previously had an ultra (streamer, pre-amp) going into the yamaha amp and it was an awesome combination. An ultra with the as701 would give you everything you'd likely need, including room correction/peq to address the issue with fatigue. The only advantage I could see going with the amp ultra is if you are set on having a one-box system. There are also often used ultras around for reasonable prices now because of people "upgrading" to the amp ultra (or whatever else satisfies their upgradeitis!)

 

[Vignus]

I believe you have a really decent Amp there, I would get an Ultra (not Amp Ultra) and try all the possible connections to see which delivers best SQ. I agree with DazSt, if you find the present sound fatiguing that would be the speakers to blame or probably the play source, not the Amp. And it would probably be easy to correct via Tone controls or Room Correction & EQ (if you get the Ultra streamer).

I have the same Yamaha amp, coupled with an Ultra, and I must say I don't find it fatiguing at all, not even over long listening sessions.
I agree it's usually the speakers that bring fatigue

 

[dankandi]

That is correct, i was thinking of the improved DAC, the room correction and better sub control of WAU may help out?

I am using the original LS50 and it gets fatiguing after 60 mins, i am not sure if the amp power supply lost control the longer you play, but the music gets a bit flabby and sibilance.

But the D3 Pro was the first Class D TPA amp i heard, and it comes with AKM DAC, so i am wondering if that is how the sound signature of Class D is like, i can clearly hear the loss of soundstage, in exchange for more bass.

Does the WAU need additional cooling? The D3 Pro i measured with a cooking IR therm, it gets around 45 degrees celsius, and rather worryingly warm to touch

 

[HansD-NL]

That is correct, i was thinking of the improved DAC, the room correction and better sub control of WAU may help out?

Room correction, placement of the speakers, sub integration etc will have a profound impact on perceived sound quality

I am using the original LS50 and it gets fatiguing after 60 mins, i am not sure if the amp power supply lost control the longer you play, but the music gets a bit flabby and sibilance.

That is not a function of the amp (if not driven to the point of clipping) but the combination of the speakers and your ears. The LS50 is a (very) forward sounding speaker, mid frequencies are in your face and with some material like rock, blues or pop (for example guitars competing for space in the mix) things can get to much for the listener. That effect gets more annoying the longer you listen mostly because your ears/brain are not able to maintain the needed corrections over time. It also depends on mood, fatigue, time of day and more factors. That's why some days or portions of the day a system can sound very different.

But the D3 Pro was the first Class D TPA amp i heard, and it comes with AKM DAC, so i am wondering if that is how the sound signature of Class D is like, i can clearly hear the loss of soundstage, in exchange for more bass.

Does the WAU need additional cooling? The D3 Pro i measured with a cooking IR therm, it gets around 45 degrees celsius, and rather worryingly warm to touch

Overall there is no real sound signature using modern and correct working amps in their linear working range. The implementation of the filters in a DAC can have effect on the output spectrum though. The D3 Pro dac/amp has tone controls so maybe that was what you noticed, don't know.

The WiiM Amp Ultra does not need additional cooling, just don't put anything directly on top of it, allow for a little space around it and you can push it to maximum output without any problem. It will protect itself should it ever get close to overheating anyway. 45 degrees Celsius is not worrying hot, totally fine.

 

[dankandi]

Will the WAU able to tune out the fatigue? I can sell the AS701 and get a WAU for minimal $200 top-up. Yamaha AS amps are quite in demand here.

 

[dominikz]

I am using the original LS50 and it gets fatiguing after 60 mins, i am not sure if the amp power supply lost control the longer you play, but the music gets a bit flabby and sibilance.

May I suggest to consider applying an anechoic response EQ correction for your LS50 speakers?
They have very nice directivity so should take EQ well.

(image source)

You can apply this EQ correction in any WiiM device, here's an EQ preset that should do the trick and take care of some of that forward character: EQ for KEF LS50 (link).

Note: You can omit the first PEQ band (at 102Hz), since low frequencies should be taken care of by RoomFit.

 

[HansD-NL]

Will the WAU able to tune out the fatigue? I can sell the AS701 and get a WAU for minimal $200 top-up. Yamaha AS amps are quite in demand here.

Any WiiM (streaming) device is able to EQ (even things out). For further info see the comment dominikz made.
If you want a one box solution the Amp Ultra is great. You can also keep the Yamaha coupled with a Wiim of your choice. A Pro Plus or Ultra would be my recommendation then.

 

[dankandi]

Any idea what is the power supply rated of WAU? The D3 Pro is 48x5 so 240W, which is lower than AS701. So that may be a factor

 

[HansD-NL]

Any idea what is the power supply rated of WAU? The D3 Pro is 48x5 so 240W, which is lower than AS701. So that may be a factor

Don't know but it can maintain it's maximum output specs. The AS701 is a class A/B amp and needs a lot more (line/input)power than a Class D design at the same output power. What's the exact context of your question? What does "So that may be a factor" mean?
Maybe you are saying that you always need full output power, don't know/understand.

 

[dankandi]

Don't know but it can maintain it's maximum output specs. The AS701 is a class A/B amp and needs a lot more (line/input)power than a Class D design at the same output power. What's the exact context of your question? What does "So that may be a factor" mean?
Maybe you are saying that you always need full output power, don't know/understand.

Sorry i mean comparing to D3 Pro, which i am using 48x5A so 240W. Could that be a factor in the sound sounding closed in? vs AS701 of course

 

[dominikz]

Sorry i mean comparing to D3 Pro, which i am using 48x5A so 240W.

I personally doubt it, unless you are blasting your amps at full power.
How loud do you listen?

Could that be a factor in the sound sounding closed in? vs AS701 of course

Comparing the amps purely on sound quality is not trivial, and it is prone to all sorts of issues that can easily taint the results. I'd advise not to give it too much weight.
In case you're interested, you can read here how far I had to go to ensure my own listening comparison of a few amplifiers wasn't affected by various sources of error (some which are obvious, and some much less so).

 

[dankandi]

I personally doubt it, unless you are blasting your amps at full power.
How loud do you listen?


Comparing the amps purely on sound quality is not trivial, and it is prone to all sorts of issues that can easily taint the results. I'd advise not to give it too much weight.
In case you're interested, you can read here how far I had to go to ensure my own listening comparison of a few amplifiers wasn't affected by various sources of error (some which are obvious, and some much less so).

Yep that is what confuses me. A lot of feedback says i am not comparing like to like, true. But i compared like what any other buyers would, just swap and plug and play.

At normal listening volume, at low volume, the AS701 sounded clearly wider, and the D3 Pro(class D) sounded more closed in and bassy.

I tried to increase the volume until i said nope, and these characteristics remained. I never blast my blast, it just sound bad always.

So i am loss at how to equalise both Amps to get fairer comparisons. Or what could be the reasons for this differences? I was thinking Class D and AB is root cause, followed by DAC implementation.

So i wish to seek more advise what am i getting into with WAU, my morbid curiousity just want something new for my LS50, i probably will order it and do A/B and sell the "worse" one. I hope WAU dont disappoint as long as it can match the airyness and will added EQ to play with

 

[dominikz]

Yep that is what confuses me. A lot of feedback says i am not comparing like to like, true. But i compared like what any other buyers would, just swap and plug and play.

At normal listening volume, at low volume, the AS701 sounded clearly wider, and the D3 Pro(class D) sounded more closed in and bassy.

I tried to increase the volume until i said nope, and these characteristics remained. I never blast my blast, it just sound bad always.

So i am loss at how to equalise both Amps to get fairer comparisons.

I'm sympathetic to your position because this is really not trivial to do.
I can fully understand how it can seem that listening to the amps like a "regular buyer" should give meaningful results, but psychoacoustic research tells us that is unfortunately very unreliable.

Our auditory perception is affected by so many things it is really difficult to make sure we're only comparing the sound under equivalent conditions. It can be done, of course, but requires the effort that very few will have the time and energy to learn how to do - and I understand why.

So my advice would be simply not to lose too much sleep about it.
Yamaha amps are usually well designed, and so is the WiiM Amp Ultra - both are capable of accurate audio reproduction, and both can be configured to achieve an objectively good sound. Just trust that the very competent engineers behind these devices designed them correctly.

Instead I'd advise to choose your electronics on features and inputs/outputs you need, and then to spend time and effort on loudspeaker placement optimization, subwoofer integration and room correction. This is where the most meaningful improvement in sound quality can be achieved.

Or what could be the reasons for this differences? I was thinking Class D and AB is root cause, followed by DAC implementation.

Reasons could be many, most of them related to various methodological, acoustic and psychoacoustic phenomena.
DAC implementation, amplifier class and power supply are not a likely cause of audible differences in reasonably well-designed devices.

So i wish to seek more advise what am i getting into with WAU, my morbid curiousity just want something new for my LS50, i probably will order it and do A/B and sell the "worse" one. I hope WAU dont disappoint as long as it can match the airyness and will added EQ to play with

The benefit of WAU will be EQ and RoomFit. But you can get this also by plugging the WiiM Mini/Pro/Pro Plus/Ultra to your existing Yamaha amp - just food for thought.

As mentioned above, if you're looking to optimize sound quality perhaps consider adding a subwoofer to your system, and learn how to integrate it correctly. You don't need to be a bass-head to benefit from a properly integrated sub; what you get is not more bass, but a smoother bass response that extends deeper. And if done well, it helps you workaround some acoustic problems in domestic rooms (like SBIR notches). I wrote about this recently here.

Good luck and I hope you enjoy your system, regardless what you decide to go for!