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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
frame11
12 posts
 
I am using a 4 channel amp from ClassD Audio. I am super happy with the amp. I purchased the CDA-1000 which is essentially the CDA 250-L x 2. I purchased the kit and assembled myself. I will be adding 2 more channels to power a multi-channel active crossover system designed by Siegfried Linkwitz (LXmini + add-on subs).

Tom, the owner is great to work with and incredibly helpful.

The idea that class d amps are inferior to class A/B/C/Z is hogwash..... typical audiophile BS.

tedkaz's avatar
tedkaz
6 posts
 
Not for nothing but why do you care if the Amp is an inefficient Class A design versus a Super Efficient Class D. You listen with your ears and not with feedback used to generate gain. Blanket ideas is what allows the marketing gurus to convince people that brown bag of dog poop is the best thing their is. If you have free clean electricity and need heat of course get the Class A by all means.
enliten
44 posts
 
Does anybody realize most 'class d' amps are simply another type of single-ended amp? Investigate it - the output is actually developed across 2 passive components - not that far away from how an OPT develops power output across its secondary. There are physical analogies within the details, but the overall system functions the same: the sound is 'built' across a passive element.

That means both amp typologies are quite susceptible to reactive output impedance of the load. The SE 845 certainly is, so are most 2 quadrant switching amps as they can't effectively sink current. This is required to effectively manage real world speakers. If a class D was well designed with full 4 quadrant operation, this would be a different column.

Also, class 'D' amps are subject to power supply/cable/drive issues just as SE amps. Proper execution of the stable implementation is absolutely critical, as Bruno has shown us to this point.....but we yet have a way to go.
psychoacustics
5 posts
 
I'm impressed with my Audio Alchemy DPA1 Stereo amp, A/D. It's very musical, it has great presence, palpability, heft and body. I've owned McIntosh, Rotel, NAD, Hegel and my other amp is an ARC tube amp. I would say the Audio Alchemy beats the Hegel H360 I owned, so it really is very good. The entire frequency range is fully present, no complaints.
mirolab
208 posts
 
I just recently tried out, and returned an NAD M22 amp.  My 20 yr old Bryston 4B-ST was misbehaving, so i sent it to them for their restoration service (replacing ALL the electrolytics!).  I thought it was maybe time to update to a new amp, and I've always loved NAD gear.    Well I thought the M22 was dismal..... simply unlistenable to me.   Now, I own (5) class A/B amplifiers that range from $800-5000, and all 120 to 300 w/ch.... And i can tell each one of them apart.  They all perform well, and have their own personality.   So don't tell me i don't know what amplifiers sound like.    The M22 was truly unlistenable to me.  I'll admit that woofer control, and dynamic power was truly amazing, but the sound was so harsh and congested, and lacked any depth.  The imaging was very weird too..... like the center was sucked out in the mid frequencies.  There was no solid center image.  I'd never heard an amp like it.  
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