WiiM Amp

[Steve Woodhouse]

There some folks like to tinker their system and having such options like what mini dsp will allow to tailor to your liking. Many of us like many option to choose from and if you don’t like that idea then that’s on you.

But Minidsp costs more than the Amp. And, if the amp has a high pass filter to the mains (removing low frequencies from them, and from the amp to have to output), what’s the problem?

And is there any evidence that the crossover in the amp isn’t both a high and low pass filter?

Traditionally, a ‘crossover’ is both a high and low pass filter.

If anyone has any information that this one is different, please let us know.

Earlier you intimated there was no high pass filter. Now you say there’s no low pass filter.

Can you confirm what you think this crossover actually is?

 

[harkpabst]

Traditionally, a ‘crossover’ is both a high and low pass filter.

If anyone has any information that this one is different, please let us know.

Earlier you intimated there was no high pass filter. Now you say there’s no low pass filter.

Yep. Right in this very thread @onlyoneme had posted his measurements of speaker and sub out (with subwoofer mode enabled).

WiiM Amp

Few things mixed up here maybe? ARC stands for audio return channel, so the Amp only gets fed and hence only supports audio, not video. Yes, you can have a video playing on your TV, but it’s only the audio that is then fed to the Amp’s HDMI ARC input. The use if the WiiM app is entirely...

forum.wiimhome.com

The results were obtained with a very early firmware and a less then perfectly performing sample, but I don't see why the general behavior should have changed. Low pass for sub out (usual stuff) and high pass on speaker out (rather uncommon with cheaper amps). These filters look surprisingly steep (like 8th order).

X-over frequency cannot be set individually for HP and LP (yet), but that's OK with me. I'm not against more flexibility, but if WiiM ever decided to give users more control over those digital filters, I hope they hide those settings deeply in some "expert mode", so regular users won't get confused.

 

[Smartplug]

But Minidsp costs more than the Amp. And, if the amp has a high pass filter to the mains (removing low frequencies from them, and from the amp to have to output), what’s the problem?

And is there any evidence that the crossover in the amp isn’t both a high and low pass filter?

Traditionally, a ‘crossover’ is both a high and low pass filter.

If anyone has any information that this one is different, please let us know.

Earlier you intimated there was no high pass filter. Now you say there’s no low pass filter.

Can you confirm what you think this crossover actually is?

Maybe I got spoiled on mini dsp wide range of option when it comes to flexibility. On mini dsp, there is setting for high and low filter along with different slope such butter worth, linkwitz Riley and among other. With mini dsp you can have over lap or put a hole on frequently response. Even a modern AVR can’t compete the option and flexibility of mini dsp. If you’re the kind of person like to tweak here and there I’m one of them.

 

[Smartplug]

Wiim amp is the first amp that I purchase that was class d. I’m also surprise how good it was sound. Every amp I purchase in the past were class ab and from what audiophile been saying class d were not hifi and high in distortion. The ability to control the woofer is mind boggling. The bass and mid bass was controlled nothing sound thin or loose.

 

[Steve Woodhouse]

Yep. Right in this very thread @onlyoneme had posted his measurements of speaker and sub out (with subwoofer mode enabled).

WiiM Amp

Few things mixed up here maybe? ARC stands for audio return channel, so the Amp only gets fed and hence only supports audio, not video. Yes, you can have a video playing on your TV, but it’s only the audio that is then fed to the Amp’s HDMI ARC input. The use if the WiiM app is entirely...

forum.wiimhome.com

The results were obtained with a very early firmware and a less then perfectly performing sample, but I don't see why the general behavior should have changed. Low pass for sub out (usual stuff) and high pass on speaker out (rather uncommon with cheaper amps). These filters look surprisingly steep (like 8th order).

X-over frequency cannot be set individually for HP and LP (yet), but that's OK with me. I'm not against more flexibility, but if WiiM ever decided to give users more control over those digital filters, I hope they hide those settings deeply in some "expert mode", so regular users won't get confused.

The PEQ feature can (or will, not sure if it’s been updated yet) include a low pass filter for band 1, and high pass for band 4. I suppose it’d just be a question of being able to apply one to the main outs, the other to the sub.

 

[harkpabst]

The PEQ feature can (or will, not sure if it’s been updated yet) include a low pass filter for band 1, and high pass for band 4. I suppose it’d just be a question of being able to apply one to the main outs, the other to the sub.

Yes, and it doesn't really matter if the high pass is on band 4 or band 1, since this numbering is really just for reference. You can assign whatever frequency you like to any of the bands, they don't have to be "in order".

WiiM really could just add the full selection of PEQ, high shelve, low shelve, high pass or low pass filter to each of the bands. However, the fact that they didn't announce anything like that indicates to me that the DSP might just lack the power to use all features at the same time ...

 

[Brantome]

The PEQ feature can (or will, not sure if it’s been updated yet) include a low pass filter for band 1, and high pass for band 4. I suppose it’d just be a question of being able to apply one to the main outs, the other to the sub.

The initial release of PEQ on WiiM only offered HS & LS for bands 1 & 4, and that was later changed to allow PK as well which bands 2 & 3 had.

 

[Steve Woodhouse]

Regarding processing power.

There’s far more grunt available on the Pro and Pro Plus than the Mini.

The latter is DualCore A7 128 MB Flash, 128 MB RAM. The Pro/Plus are QuadCore A53 512 Flash 512 RAM. I’m not even sure what that means, but it certainly sounds impressive!

I couldn’t say about the Amp (does anyone know?).

At the moment the Mini can do pretty much anything and everything the Pros can, so you’d have to imagine the latter two can handle more bands of PEQ, and more flexibly, even if the Mini can’t.

Indeed, you’d have to wonder what the extra is there for, given the fact that the extra processing appears to be sat there doing nothing at the moment.

 

[Brantome]

Regarding processing power.

There’s far more grunt available on the Pro and Pro Plus than the Mini.

The latter is DualCore A7 128 MB Flash, 128 MB RAM. The Pro/Plus are QuadCore A53 512 Flash 512 RAM. I’m not even sure what that means, but it certainly sounds impressive!

I couldn’t say about the Amp (does anyone know?).

I’d say the same as the Pro and Pro Plus.

At the moment the Mini can do pretty much anything and everything the Pros can, so you’d have to imagine the latter two can handle more bands of PEQ, and more flexibly, even if the Mini can’t.
Indeed, you’d have to wonder what the extra is there for, given the fact that the extra processing appears to be sat there doing nothing at the moment.

The Mini doesn’t have Roon, Squeezelite, ChromeCast, AirPlay casting or lossless Amazon Music multi room off the top of my head, so the extra resources in the Pro and Plus have already been put to good use.

Edit: don’t know why, but your comment made me think of the Monty Python sketch re what have the Romans ever done for us

 

[Steve Woodhouse]

I’d say the same as the Pro and Pro Plus.



The Mini doesn’t have Roon, Squeezelite, ChromeCast, AirPlay casting or lossless Amazon Music multi room off the top of my head, so the extra resources in the Pro and Plus have already been put to good use.

Edit: don’t know why, but your comment made me think of the Monty Python sketch re what have the Romans ever done for us

Cheers, I wasn’t aware of all that - possibly because I’m not sure I’ll ever use any of it. But the information is great.

Whilst I’m no tech expert, just applying a bit of logic. The Mini came first. It was designed and released as a finished product, albeit with the possibility of updates.

By the time the Pro and Pro Plus came along I know that PEQ was already on the cards. Now, the 4 band PEQ we have, they’ve squeezed that onto the Mini, into what was effectively ‘leftovers’ processing power. The things you list, if I compare them to everything else the WiiM Pros do, it doesn’t look like a lot, especially considering the huge amount of surplus processing power they have over the Mini.

In short, if WiiM got 4 bands of PEQ onto the Mini, which was never designed to handle that, it’d be an extremely unfortunate set of circumstances which would result in the features you mentioned using up every last scrap of processing, leaving nothing for more bands of PEQ, and the ability to be more flexible with them.

But that’s just my own, uneducated guess. I bet I’m not far wrong, though.

Time, as ever, will tell.

 

[harkpabst]

Is it really the processor doing (P)EQ in all current WiiM devices? No dedicated DSP? That surprises me a bit, I must say.

 

[Steve Woodhouse]

Is it really the processor doing (P)EQ in all current WiiM devices? No dedicated DSP? That surprises me a bit, I must say.

I couldn’t say definitively.

But there have been teardowns on all the streamers, not to mention the amp, and I’ve not heard anyone say “Hey! What’s this dsp chip doing in here?”

 

[Brantome]

Is it really the processor doing (P)EQ in all current WiiM devices? No dedicated DSP? That surprises me a bit, I must say.

Nobody has mentioned the presence of a DSP in any of the devices and tbh, you’d have thought we would have got PEQ a lot sooner had they had one.

 

[Steve Woodhouse]

I’m not sure a dsp chip wouldn’t be overkill.

Let me explain. If we’re talking about PEQ, I suspect that part of dsp is fairly low maintenance. I mean there’s a 4 band PEQ been added to the Mini retrospectively, and that’s a £90 puck.

I suspect the big drain on processing power is the measurement and computing what needs to be done to correct things.

As I’ve said previously, my guess is that this will be done in your phone, which has more processing power than £1,000+ AV amps.

I mean, the HouseCurve app costs <£10.

 

[Vladetz]

I’m not sure a dsp chip wouldn’t be overkill.

Let me explain. If we’re talking about PEQ, I suspect that part of dsp is fairly low maintenance. I mean there’s a 4 band PEQ been added to the Mini retrospectively, and that’s a £90 puck.

I suspect the big drain on processing power is the measurement and computing what needs to be done to correct things.

As I’ve said previously, my guess is that this will be done in your phone, which has more processing power than £1,000+ AV amps.

I mean, the HouseCurve app costs <£10.

Amlogic a113x in wiim amp is quite capable

 

[canard]

if at first, at the beginning of autumn 22, wiim announced a 10band peq, they quickly, during this autumn 22, announced that the peq could only be a 4 band for the mini due to lack of power-memory , but 10 bands for the pro, and was initially supposed to be in January...23... ( finaly in september 23, but 4 bands for mini pro and plus)

 

[harkpabst]

Amlogic a113x in wiim amp is quite capable

So at least the WiiM Amp does come with a dedicated, separate DSP chip, indeed? Thanks for the information.

This makes a lot of sense to me. Digital filters are not set-it-and-forget-it like analog filters. They consist of algorithms executed in real-time. The more complex the filter operations, the greater the risk that a general purpose CPU might not cut it anymore.

 

[Steve Woodhouse]

if at first, at the beginning of autumn 22, wiim announced a 10band peq, they quickly, during this autumn 22, announced that the peq could only be a 4 band for the mini due to lack of power-memory , but 10 bands for the pro, and was initially supposed to be in January...23... ( finaly in september 23, but 4 bands for mini pro and plus)

Would you care to provide a link?

 

[Brantome]

Would you care to provide a link?

That’s pretty much my recollection too. It was either mentioned in this forum or in the very lengthy WiiM threads on AudioScienceReview. To be fair, it has swung back and forth since it was first mooted and as usual with WiiM, it’s best to wait till something is actually implemented as I’m sure they’ll admit themselves that they can sometimes be over optimistic in striving to please their customer base. User patience is a necessary virtue as well

 

[acubz]

I have auto sensing off, but the input switches if I'm listening to line in and then turn on my TV (HDMI). Is there a way to really disable automatically switching inputs?