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Class D = Trash?

So, I'm on my second class D amp. The first one, a Teac AI-301DA which claimed to use an ICE module, was unlistenable trash. I burned it in for a few weeks, it just couldn't perform, so I sent it back. Following that, I tried the new Emotiva A-300 (class A/B). It was significantly better, but lacking in too many ways for my tastes. So I changed gears, got an 845 SET from China -- and it was an immediate and massive improvement.

So, before I went further down the SET road, I wanted to try a better class D product using a modern class D module. I settled on the D-Sonic M3-800S with the Pascal module and custom input stage. I read from reviews that these things like to have big cables, so I picked up an eBay 8 gauge power cable (Maze Audio, el-cheapo Oyaide copy plugs, braided 4-wire cable) to go along with it.

Mid-range GONE.
Soundstage depth CRUSHED.
Euphonics DISAPPEARED.

Yes, resolution went up. Driver control went up, allowing me to play compressed rock/pop and orchestra with the speakers being able to render it all. But enjoyment in the sound is basically gone. Using my best power cable (LessLoss Original) improved performance, but didn't fundamentally change the amp's nature. I ran back to my headphones (Focal Utopias) to detox my ear canals.

So, how long does a class D need to burn-in? I want to give it a fair shake before writing the technology off forever. 
madavid0
guidocorona
4,298 posts
 

@2channel8There

@2channel8T@2channel8

@2channel8T@2channel8T

There is s nothing unique in class D break-in and re-breakin.... Amps of any type, if sufficiently complex, will take hundreds of hours to break-in.... Even the basic music system in my Toyota Prius took months to sound decent. My class A/B ROwland M625 stereo and M725 monos took about 1000 hours to sound their best. 


The 1500 hours I mentioned is the upper limit of my own experience with amps... It did take about that much for my Rowland M925 monoblocks to stabilize.


As for needing to re-break-in, it all depends on how long devices have been off line. If I leave my system offline for several days, a few hours of warm up returns the system to top performance level.. On the other hand, when I moved from TX to SC, my system was in storage for over 6 months... When I finally reconnected and restarted it, it took a couple of weeks for it to return to top performance... Perhaps 300 hours of making music at minimum volume.


G.



 

bassdude
497 posts
 
Well... a lot of techy discussion here... and... I don't really know why my "Class D Audio" SDS-470C sounds so incredible (e.g. Ice vs Hypex vs something else or switching vs linear, etc.) - I just know it does.  

And... it seems to sound as good or better than my other amps, which are very good.  

And... I've not tried any other class d amps... so... I have no basis for comparison - I'm not really sure I need any - it sounds so grand!    
h2oaudio
38 posts
 
Hi Tim, Thanks

I apologize for what I wrote was not very clear. So let me rephrase and make it a bit more clear. You’re right that there is not a direct relationship between good bass and an analog power supply, which makes sense, after all power supply is but one of the many fundamental aspects of any amplifier design. Great sounding power amplifiers requires many aspects of the design, and not just the power supply. What I can say from what I have implemented and heard is that an unregulated analog power supply seem to always sound better than those with SMPS. And this is strictly in the context of class D Icepower. As indicated, I have implemented and listened to the NCore 400 modules with an analog power supply of my own design, but cannot compare to any Ncore (400 or otherwise) modules implemented with SMPS and so therefore cannot make any evaluation as compare to the Ncore 400 modules with my own an analog power supply. I have requested to buy sample of Ncore 1200 from Hypex to test as I am a manufacturer and have been declined by Hypex. It seems as though Hypex wants to supply to only those manufacturers with reputable brand names, sort of exclusive club if you know what I mean, since H2O is a no body apparently, and that is my feeling. My goal is obviously to find the best technology which sounds good to high-end community. No matter though, from what I have implemented and heard, especially with Icepower, there is absolutely nothing to fear, at least from my point view.

Henry
h2oaudio
38 posts
 
Tim,

I wanted to add that though I have not have a chance to listen to one yet! But I believe the D-sonic amp is an great amp from what I have read.  And ice on the cake is the price especially.

Henry
atmasphere's avatar
atmasphere
11,849 posts
 
Personally I have lost all interest in hard to drive speakers because I find their total cost of ownership just too high for little value.
+1 on that!

When you can connect headphones to the power supply of any amplifier and hear the audio signal, you may count on the fact that the power supply is contributing to IMD. This is a very audible form of distortion! It is for this reason that we have a separate power supply for our driver circuits as opposed to our output circuits.

IMO this should be the case in a class D amp too, and I think that should pan out as the input circuitry usually has very different requirements as opposed to the output section.
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