Atma-Sphere Class D Mono blocks

[morricab]

View attachment 118928
Ok, let’s see what this D class buzz is all about!

Very curious

 

[DetroitVinylRob]

Cold off the FedEx truck with about 15 minutes of mains time. They sound very detailed and balanced. Wow, when these things get thoroughly warm and settled we know they will be better.

 

[morricab]

Projecting ..?

I must have missed your scienctisk* methodology in your response..

Power necessary is a sliding scale , speaker sensitivity , listening levels and music crest factors are some of what dictates the necessity to feed the monster , this incessant my way or nothing is just nonsense , maybe Fauci did get to you after all

So no 3 watts with all levels of distortion measured that cant be heard by you is not the only way ..

But please feel free to educate me and others who’s choice is to listen to large scale lower sensitivity speakers with unclipped music with some of your science ..!





Regards

No one is saying you or anyone else doesn’t have a choice…you may make bad choices but they are (mostly) not life or career threatening.
You can’t change the simple fact that compression starts from the first mA of current through the wire and only gets worse the more you apply. The lower the sensitivity, lower in SPL it becomes a significant factor. All lower sensitivity speakers will compress transient peaks at surprisingly low SPL and this will only grow worse the more watts applied.

High sensitivity speakers, particularly pro drivers designed to minimize this problem, will of course do the same but it will become a problem at higher SPL…usually well above what we listen to at home.

This is not speculation, it’s physical fact. The perception aspect of it is where it might get a bit murky as human preferences are never that well aligned. Perhaps you personally don’t hear the unnatural dynamics of nearly all low/mid sensitivity speakers irrespective of power? Once you hear it and the relative freedom from compression of a good high sensitivity speaker , you can’t really unhear it.
It’s why big box speakers of the low/mid sensitive type just sound kind of dead at low volume and compressed at high volume.

I once had a pair of Dynaudio Contour 1.8 mkII that were very well designed as a conventional speaker goes. They were smooth and balanced and with volume levels from 75-85dB sounded great with pop music I mostly listened to at the time. As my music tastes evolved to wider dynamic range fare…they didn’t do so well. At low volumes they dropped out, so to speak and sounded blunted and congested when cranked up. I thought, like you that just put enough power and they will sing on the peaks. I eventually ended up with over 500 watts per channel of high end accepted amplification but to no avail…they refused to sound anything other than compressed and congested with any real dynamic material. Now perhaps they were extreme, being 85dB and 4 ohms, I hear something similar, if to a lesser degree, on most cone/dome speakers.

One exception I know of is a speaker I used to sell, tge DynamiKKs Athos 10. Even though it is a mid sensitivity speaker with 91 dB, it uses pro drivers with huge headroom. Only the tweeter is horn loaded on this but the large 8 inch mid and beastly 10 inch woofer have impulse handling of well over 1000 watts and have vented voice coils. We have compared it to other, nominally 91dB speakers and the difference in dynamics is stunning…but it still doesn’t outdo a high sensitivity speaker…horn or otherwise.


Losses in complicated crossovers just exacerbate the issue and reduce dynamics further, which is why my DIY system is full active and my main system only has a single cap for a crossover element. The DIY system is 99dB(although the compression tweeter is a full 110dB with no passive parts) and the main one 98dB. I run everything from 3.5 watts up to 30 watts SET amps. None sound compressed or straining at peaks in the upper 90s.

 

[D.Duttilleux]

These comments just tell me you don’t know any more about what science is or isn’t than Dr. “I am science” Fauci. You conflate engineering practice with scientific understanding. Science is a methodology that involves conjecture and measurement. I am taking both into account to build a hypothesis based on general observation.

Now it's getting interesting

One can easily fill 1000s of pages with philosophy of science, but let's take a huge, yet illustrative, shortcut that (also) touches on current events:

"In 1921 Einstein lent his support to the Zionist movement. But he was always careful to explain that he supported “cultural Zionism,” not “national Zionism.” That meant support for Jewish refugees in Palestine and for institutions like Hebrew University, but not support for a Jewish national state, which he feared would lead to conflict with Palestinian Arabs."

 

[D.Duttilleux]

View attachment 118934
Cold off the FedEx truck with about 15 minutes of mains time. They sound very detailed and balanced. Wow, when these things get thoroughly warm and settled we know they will be better.

Nice system

Would it be too much to ask to take a close-up photo of the radial (mid-range) horn?
I'm curious about the throat section.

 

[DetroitVinylRob]

Nice system

Would it be too much to ask to take a close-up photo of the radial (mid-range) horn?
I'm curious about the throat section.

Yes, here you go. I’m curious, what are you looking for?

 

[D.Duttilleux]

Yes, here you go. I’m curious, what are you looking for?

Thanks for the picture.
It's the transition from the driver's exit to the (horn) throat that interests me. The transition is potentially a source of diffraction and therefore distortion.

This is a similar (prototype) horn with a smooth transition (without sharp edges):

 

[Audiohertz2]

No one is saying you or anyone else doesn’t have a choice…you may make bad choices but they are (mostly) not life or career threatening.
You can’t change the simple fact that compression starts from the first mA of current through the wire and only gets worse the more you apply. The lower the sensitivity, lower in SPL it becomes a significant factor. All lower sensitivity speakers will compress transient peaks at surprisingly low SPL and this will only grow worse the more watts applied.

High sensitivity speakers, particularly pro drivers designed to minimize this problem, will of course do the same but it will become a problem at higher SPL…usually well above what we listen to at home.

This is not speculation, it’s physical fact. The perception aspect of it is where it might get a bit murky as human preferences are never that well aligned. Perhaps you personally don’t hear the unnatural dynamics of nearly all low/mid sensitivity speakers irrespective of power? Once you hear it and the relative freedom from compression of a good high sensitivity speaker , you can’t really unhear it.
It’s why big box speakers of the low/mid sensitive type just sound kind of dead at low volume and compressed at high volume.

I once had a pair of Dynaudio Contour 1.8 mkII that were very well designed as a conventional speaker goes. They were smooth and balanced and with volume levels from 75-85dB sounded great with pop music I mostly listened to at the time. As my music tastes evolved to wider dynamic range fare…they didn’t do so well. At low volumes they dropped out, so to speak and sounded blunted and congested when cranked up. I thought, like you that just put enough power and they will sing on the peaks. I eventually ended up with over 500 watts per channel of high end accepted amplification but to no avail…they refused to sound anything other than compressed and congested with any real dynamic material. Now perhaps they were extreme, being 85dB and 4 ohms, I hear something similar, if to a lesser degree, on most cone/dome speakers.

One exception I know of is a speaker I used to sell, tge DynamiKKs Athos 10. Even though it is a mid sensitivity speaker with 91 dB, it uses pro drivers with huge headroom. Only the tweeter is horn loaded on this but the large 8 inch mid and beastly 10 inch woofer have impulse handling of well over 1000 watts and have vented voice coils. We have compared it to other, nominally 91dB speakers and the difference in dynamics is stunning…but it still doesn’t outdo a high sensitivity speaker…horn or otherwise.


Losses in complicated crossovers just exacerbate the issue and reduce dynamics further, which is why my DIY system is full active and my main system only has a single cap for a crossover element. The DIY system is 99dB(although the compression tweeter is a full 110dB with no passive parts) and the main one 98dB. I run everything from 3.5 watts up to 30 watts SET amps. None sound compressed or straining at peaks in the upper 90s.

Havent appointed the full time to respond , so will abbreviate.

1. I dont think you have had a really good large scale dynamic speaker, using poor deficient speaker designs to say you have is not going to help your discussion .

2. No decent designed loudspeakers system should sound strained at 98 db , a large scale low efficiency system with the correct amplification power will not lack jump or dynamics , you half THD every time you double driver area ..!

3. The real advantage to running horns domestically is to hear low wattage toob amps and personally only SET makes it worth the effort and it better be the correct SET..

4. Any large scale multi driver or multi tower linesource , esl or dynamic type speakers built to proper scale will match horns at every corner all day everyday .!

So no there is no disadvantage in 2023 when high powered amplifiers have been available for decades and yes they are bad sounding Toobs and horns just as bad sounding SS amps and dynamic speakers , everything has to be matched regardless for proper results ..



Regards

 

[morricab]

Havent appointed the full time to respond , so will abbreviate.

1. I dont think you have had a really good large scale dynamic speaker, using poor deficient speaker designs to say you have is not going to help your discussion .

2. No decent designed loudspeakers system should sound strained at 98 db , a large scale low efficiency system with the correct amplification power will not lack jump or dynamics , you half THD every time you double driver area ..!

3. The real advantage to running horns domestically is to hear low wattage toob amps and personally only SET makes it worth the effort and it better be the correct SET..

4. Any large scale multi driver or multi tower linesource , esl or dynamic type speakers built to proper scale will match horns at every corner all day everyday .!

So no there is no disadvantage in 2023 when high powered amplifiers have been available for decades and yes they are bad sounding Toobs and horns just as bad sounding SS amps and dynamic speakers , everything has to be matched regardless for proper results ..



Regards

1) What, in your view, constitutes a really good box/cone/dome speaker? What context does it need to be in to “count” for you as my having sufficient experience? Did I have to own them or is hearing them extensively at friends, dealers and shows sufficient to meet your criteria?

2) You say this, but I hear this, over and over again. It’s not just the peaks, it’s also the micro dynamics that don’t sound as real. Is it the electronics? To some extent but definitely not only.

3) Don’t necessarily disagree, my experience with SS on horns is not a pleasant one.
4) Disagree with this one…sorry it just ain’t so. Only the biggest planar hybrids (like Ron’s Pendragons…or big Genesis) can compete. If you have never heard some of the speakers on my list then you wouldn’t understand…especially the LV, AC and biggest Acapella speakers…

We are not talking about bad this or that…

 

[D.Duttilleux]

I once had a pair of Dynaudio Contour 1.8 mkII that were very well designed as a conventional speaker goes. They were smooth and balanced and with volume levels from 75-85dB sounded great with pop music I mostly listened to at the time. As my music tastes evolved to wider dynamic range fare…they didn’t do so well. At low volumes they dropped out, so to speak and sounded blunted and congested when cranked up. I thought, like you that just put enough power and they will sing on the peaks. I eventually ended up with over 500 watts per channel of high end accepted amplification but to no avail…they refused to sound anything other than compressed and congested with any real dynamic material. Now perhaps they were extreme, being 85dB and 4 ohms, I hear something similar, if to a lesser degree, on most cone/dome speakers.

I hear you.
After owning several Dynaudio speakers and listening to most of their products, I decided to switch to 'high efficiency' for the exact same reasons.
The upper bass hump in Dynaudio's monitor sized 2 ways (around 100 Hz), due to the overdamped port tuning, is unbearable. Although I have also developed an aversion to polypropylene cones > the sound of plastic - I can live with that.



The Contour 2.8 is one of the better Dynaudio products in the brand's history, because of the Esotar T-330 D tweeter and the use of a passive radiator instead of ports.
Nearly 25 years ago I found a used pair that one of my best buddies bought for about €450; approximately 1/10th of the price when new.
This purchase turned out to be one of his most profitable investments. As a result of damage incurred during moves to cities all over the world and the subsequent payment from transport insurers, this pair has recouped at least 20x.
And that's not all. Recently, water damage yielded another €2,400

 

[DetroitVinylRob]

Thanks for the picture.
It's the transition from the driver's exit to the (horn) throat that interests me. The transition is potentially a source of diffraction and therefore distortion.

This is a similar (prototype) horn with a smooth transition (without sharp edges):View attachment 118946

I believe John Wolff worked with Edgarhorn on this T3 midrange design.

 

[D.Duttilleux]

Any large scale multi driver or multi tower linesource , esl or dynamic type speakers built to proper scale will match horns at every corner all day everyday .!

To a certain extent. The size of a system is indeed decisive (number and type/size of drivers, etc.), but the efficiency of horns is unparalleled.

 

[D.Duttilleux]

I believe John Wolff worked with Edgarhorn on this T3 midrange design.

Legendary Dr Bruce Edgar (RIP).
Horn throat distortion products (non-linearities) are related to the wavelength and expansion of the wavefront.
The midrange horn in the T3 seems 'clean' enough for the passband.

 

[Republicoftexas69]

Now it's getting interesting

One can easily fill 1000s of pages with philosophy of science, but let's take a huge, yet illustrative, shortcut that (also) touches on current events:

"In 1921 Einstein lent his support to the Zionist movement. But he was always careful to explain that he supported “cultural Zionism,” not “national Zionism.” That meant support for Jewish refugees in Palestine and for institutions like Hebrew University, but not support for a Jewish national state, which he feared would lead to conflict with Palestinian Arabs."

Thought WBF was a politics free zone?

 

[Solypsa]

... as I've gotten older I've really come to the position that there are no good justifications for low efficiency and low impedance; both simply mean that whatever amp driving the speaker has to work harder and all amps regardless of technology make more distortion (audible as reduced detail, a less pleasant midrange and so on).

Ralph, I know you have spoken many tines about this. If you are feeling generous, would you remind me ( or link to prior discussion ) a bit more in detail about the rise of distortion into decreasing impedance? For example is it mostly IMD etc.?

This is interesting to me as it seems many makers of class D amps encourage lower impedance loads ( especially in pro products ) as their amps 'make more power' into those loads.

Thanks in advance...

 

[D.Duttilleux]

Thought WBF was a politics free zone?

"...let's take a huge, yet illustrative, shortcut..."

I could just as well have made the comparison between various audio forums versus the forum that pretends to be scientific. The latter forum is far from scientific according to the philosophy of the great (quantum) physicists and philosophers of science. A fairly large and especially loud group of members has become so absorbed in a totalitarian variant of objectivism (measurements = truth) that the forum shares similarities with a cult.

 

[Republicoftexas69]

"...let's take a huge, yet illustrative, shortcut..."

Was pointed at both of you, an it is a factual statement. Love the ignore feature.

 

[D.Duttilleux]

In that case, please feel free to ignore my post.

 

[Republicoftexas69]

In that case, please feel free to ignore my post.

Yep sure will Slick.

 

[PYP]

"...let's take a huge, yet illustrative, shortcut..."

I could just as well have made the comparison between various audio forums versus the forum that pretends to be scientific. The latter forum is far from scientific according to the philosophy of the great (quantum) physicists and philosophers of science. A fairly large and especially loud group of members has become so absorbed in a totalitarian variant of objectivism (measurements = truth) that the forum shares similarities with a cult.

more relevant to have pointed out that Einstein played the violin and would play Mozart when he was stuck on thinking through his theories. Was Mozart a party to the special theory of relativity?