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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

Showing 8 responses by seanheis1

seanheis1
595 posts
 
I can definitely detect that element of...whatever it is. Dryness? Poor blending of upper- mids into highs? Lack of weight? There's a SOMETHING to the sound that hints to listener fatigue.
I experienced the same with Ice Power amps. Dry, cold, clinical...lacking depth and instruments not decaying properly. I purchased the amp used so it wasn't a break in issue...I started a thread about it and it appears that the switching frequencies aren't currently high enough to avoid degrading the signal. If it was a simple break in issue, they would be broken in at the factory. 

Don't give up on Class D though. When the switching frequencies improve, they will become the solid state amps of choice. Some folks don't hear what we hear and they are fortunate to enjoy these small and efficient power houses. More power to them. 
seanheis1
595 posts
 
Again, one experience with ICE modules cannot possibly speak for all Class D amps, just the one amp you heard. Goodness folks. I heard a poor tube dac once so they all must have a ways to go.....crazy thought process correct?
These issues with amps that use Ice modules are well documented on this forum. Amps using NCore, Pascal, and Abletec are generally viewed as favorable. NCore is often times described as similar to Ice, but improved. Plenty of folks don't care for NCore though...None of these Class D amps are as universally agreed upon compared to Class AB offerings from McIntosh or Mark Levinson.  
seanheis1
595 posts
 
Very interesting point about switching frequencies… What is the acceptable switching friequency range is targeted by the pundits?
Below is a quote from George from the Class D technology thread. 

The day will come when Class D will compete and very well be better than any linear amps tube,s/s, class A, AB or whatever, BUT!!

 Class D needs much higher switching frequency (needs to be at least 5 x higher) technology isn't there yet but in the future it will come, only then will ClassD become a contender. Till then good for budget hifi and subwoofer/bass amps.

Technics has progress the Class D race and developed 2 x the present switching frequency with their own made components, in this amp but it’s very expensive $20-30k
https://forum.audiogon.com/posts/1334662?highlight=Technics

When the switching frequency is 3mhz or better, then it can be called hi-end, and will own it myself, then my linear heavy boat anchors will be sold or become door stops.



Cheers George
seanheis1
595 posts
 

Guido, is there any scientific explanation behind these Class D break in numbers? I can see speakers maybe needing a bit of time to break in....but transistors???

Given that break-in of a class D power amp ranges from 600 hours to approximately 1500, asking a manufacturer to exercise the device for upwards of a couple of months before shipping it to a dealer may be woefully unrealistic… Of course, everything is possible…. For a commensurate list price uplift.

 

G.



seanheis1
595 posts
 
The Marantz PM-10 and NAD M22 are hypex Ncore. If you haven't been pleased with Class D in the past, I can't imagine that a new name on the box will change things much. 
seanheis1
595 posts
 
This link is to the best thread that I know of discussing the pros and cons of Class D technology vs Class A. The limitations of each technology is discussed in great detail.   
 
https://forum.audiogon.com/discussions/class-d-technology
seanheis1
595 posts
 
Secondly...YES...break in time is crucial. When I bought my 501's, they'd been off for ~ year. I think they went through a break in period at that point, as they continually sounded better (and proceeded through the 'goofy midrange' 'echos in the mid bass' stages, then settled in). 
Very helpful post. IcePower is definitely improving with their revisions. 

All this talk about break in is interesting. And talk about breaking in a used amp is even more interesting. I wonder if the amp is "breaking in" the speakers? Not much science behind that thought, but there's not much science behind breaking in transistors either...  
seanheis1
595 posts
 
I have a used D amp that needs to be re-broken in due to it being in storage for 1 year and 6 days. I would like updates at the following intervals - 600, 900, & 1500 hours...we can have listening sessions over Skype to monitor progress.
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