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.
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.
Everyone in audio has a different opinion on what sounds good and what does not. There are many factors that influence your opinion on equipment and its associated technology. Understanding the technology is interesting but, for me, how a piece of equipment sounds in MY system is more important.
After some discussion, my friend loaned me his James Romeyn "Class D" mono block power amplifier and I liked them very much. They sounded much better than my Luxman 590ax Class A integrated amplifier (solid state). The music was more open, detailed with much improved bass. I was very surprised and could not believe it. And, yes, I was hearing sounds that I have not heard before.
I consulted with James and decided to buy his Hypex NCore NC400 dual mono block class D power amplifiers ($2,980) with 2 NC400 amplifiers per side with the NC1200 power supply. He highly recommended his Class D dual mono version for improved sound quality and power.
The amplifiers finally arrived and they were a huge step above his mono block power amplifiers. The sound quality from my Hypex NCore NC400 Class D duel mono block power amplifiers is amazing. Burn in time was about 3 weeks but they sounded very good out of the box. However, as I was instructed. I made no judgement until after the 3 weeks.
My sound system sounds much improved over my Luxman 590ax Class A integrated amplifier. I mentioned this before in previous posts but we removed the R141 chip from the 4 NC400 amps that allow increased volume setting from my Bricasti M1 SE DAC. My DAC is going direct to my Hypex NCore NC400 mono block power amplifiers and I am not using a pre-amplifier. I am using the James Romeyn Pure Balanced POWer Fully Balanced Interconnect cable with Cardas Rhodium XLR Connectors. The Rhodium connectors took several weeks to burn in and sounded horrible out of the box.
I am hearing details, imaging and bass that I have not heard before. My system now offers breath taking detail, transparency, lack of noise, and excellent dynamics that I did not hear with the Luxman 590ax Class A integrated amplifier.
I purchased the Hypex NCore Class D amps from James Romeyn Music and Audio, LLC (James). He was very helpful answering my many questions and I suggest you contact him for more information on his assembled Hypex NCore Class A amplifiers (he offers 3 models). Please see this link:
madavid0, my experience with class D amps I had in my system is that two amps based on NCore and three based on ICEpower took about 1K hours. However, my current Rowland M925 monos reached at least 1500 hours before stabilizing.
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.
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.
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.
IMO, if the component "ain't happening" new out of the box, then breaking in will only result in minor improvements. The sonic character is either there or it isn't. You may talk yourself into liking it, however it probably won't win you over if you are truly honest with yourself.
seanheis196 posts04-01-2017 9:36am 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.
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
Yes it actually, the filter that’s needed to rid that switching frequency and all it’s artifacts that does the damage also to the audio band at the moment. ( switching frequency artifacts left over are the buzz-saw ringing that one sees on test 1khz square waves) http://www.stereophile.com/images/archivesart/805CIAfig2.jpg (And the filter also causes phase shifts in the 5khz to 20khz of the audio band)
If the switching frequency were higher, then the filter can do it’s job without effecting the audio band, and get rid of all ringing that’s left over on those square wave tests.
So I wait in hope for technology to advance so the switching frequency can be up around 5mhz. Technics in the above link have got it up, with special transistors to 3hmz they are showing the way, but that amp costs $20-30K and is special order only.
George, funny thing that, trusting my own ears, I really can't hear any artifacts in my gear... SMPS switching at 450 Khz or so. Real heavenly actually.
But I admit that some amps switching at similar frequencies are the ones that should be marketed only as varmint chasers *Grins!*
I have owned many amps, but currently have a bel canto ref 500 (class d) powering a pair of monitor audio pl200 speakers. I needed enough power to get the ribbon tweeters to liven up. Tried a Bryston and couldn't listen for more than 5 minutes - way too harsh. With the bel canto, and a ps audio ac-12 power cable, I get the low end of the bryston without the aggression of the bryston's treble. After the amp/speaker match, everything else fell into place for me. I feel this amp/speaker match is critical to the entire system - and likey less a matter of amp design than component matching.
Only tubes for me. KR audio va 900. Using Kt 120 tubes. Great sounds all around. Organics, transparency, soundstage depth and width. Open midrange with a sweet and airy treble. Tight bass.
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.
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.
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.
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.
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.
Interesting read this thread has been! Just thinking out-loud.... I bought my Marantz PM-11s3 a year ago and listened to many class D amps including NAD, Devialet and others in its price range and to me there was no comparison! The PM-11s3 was a much better listen in every way. Now what scares me is that the new Marantz PM-10 is Class D. And it's priced at $9000, a full $4000 more than the PM-11s3!!! I really hope they got it right and it’s a major jump forward for the Class D technology without these long break-ins and loss of performance or they are headed for a major black eye! That would be a terrible let down considering how good their Reference Series has been...
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.
Here is what a well known quality speaker manufacture believes with what they put into their own active monitors.
JM Labs Focal Speakers. "
The amplifiers are conventional Class A/B designs rather than the increasingly common Class D option, because Focal thinks the traditional technology gives a better sound."
I have had a number of Amps; SS, Tube, Class D. 3 years ago I replaced my Cary V12R (Tube), with a Bel Canto, then I (in my opinion) upgraded to a Spectron Musician III with the remote sense cables (I will be listing this next week), I recently upgraded again to the Merrill Audio Thor Monoblock's. For reference my pre-amp is a Vac Signature Mkiia with Phono Stage, I have various turntables, a Bluesound Vault and the Speakers are Dynaudio C1's. IMO the Thor Monoblock's are without doubt the best Amps I ever owned and frankly one of the best I have heard. In my set up, having a quality pre-amp helps, the Dynaudio's love power - the bass comes alive. I am not an audiophile, do not have 'golden ears etc so I cannot talk about 'Blackness', "Presence', 'Soundstage' etc....all I can tell you is that I have asked friends to pick their favourite track, then sat them in the best position to listen and walked out the room. I come back in and they are speechless, one even cried ...but i expect the wine had something to do with that! To the original question, Merrill recommends 500 plus hours of burn in. I'm 49 years old, I am sure the frequency spectrum I hear is not the same as when I was 19...but for me... I am hearing the best reproduction of music I have ever heard in my life. Again, just my opinion, and we all have one !!! LOL
If the amps are a recent purchase, they may not be properly broken in. Give them some 1000 hours of break-in... They should have sweetened considerably, and the bass should be rendered OK. However, until now, W4S has not been one of the Class D brands with a house sound that has delighted me at RMAF.
I have not heard the Thors yet, but I have tested at length the Merrill Audio Veritas and Teranis... My friend Merril makes wonderful amplifiers indeed, so I am not at all surprised that you are enchanted by the Thors. With 500 hours, your Thors will sound great, but they might continue to bloom further for as many more hours... Feed them some white noise or FM interstation hash at lowish volume whenever you are not listening to them, including night time... That will maximize the break-in speed.
Class D has and will continue to have a great future in Audiophile systems. The key is Sigma-Delta processing. Without it, yes these are harsh and mostly useless products. With it, it all comes together. Do your research on-line and in home and you will recognize this technology and understand. If not, take more Valium.
I’m not sure if this is clear, but amps are subject to any thing in front of them. Buying an integrated w/ DAC and judging all Class D amps based on that is not going to give you a very good base upon which to judge.
Also, B&O have gone through three major generations, the latest full amp modules are the AS/ASP. There is also now a chip only version, which allows manufacturers to buy the theory, without the rest of the parts. God only knows what each maker will do with that, so it is completely unfair to use this as a basis to judge ICEPower in general as well.
The credible comparisons I have read between ICEPower AS/ASP vs. nCore put them pretty close. I think bigger differences, like in purely linear amps, will be found with amp-killer speakers. "Normal" amplifier friendly speakers may not care very much.
From my listening, I put the ICEPower AS/ASP modules as good as the Parasound A21/A23 series. Both are very modern, clean, open and quiet, and grainless. Based on this, I debunk the idea that class D is in any way inferior to linear amps. Now, if you want to argue your particular tube amp sounds better than that, well go ahead, but it won’t be due to digital vs. analog.
Greg ., Your gonna have to break down and spend some serious cash! And purchase a Burmeister intergraded amp its only 10 Grand No D trash here . I am working 3 jobs to support one . Its worth it .
I am glad to hear you are happy with Bel Canto Ref 600Ms, as I am looking into getting a pair myself. If you don't mind me asking, what source/DAC/pre are you using in front of the Bel Cantos that gives you the nice results?
Wishful thinking, more like breaking the owner down, more like it making him submit.
At 2hrs listening every day of the week, that's close to 2 years before break-in, that's just ludicrous, and you would have rocks in your head to leave any poweramp on while nobody's at home.
@sanvara - I had a crown xls1500 that sounded great. Recently bought a used pair of Ghent audio monoblocks and they sound even better.. they're using the ICEpower ASP modules, I believe. I was doubtful they'd sound better.. but they do.
northernfox: we've been super impressed with the Bel Canto REF600M as well. They're a huge step up from the old REF500M in my opinion. We're currently driving them in one of our demo systems being fed by the Bel Canto DAC3.7. An excellent combination.
I have rocks in my head as my SS amp and server are always on. I also keep my air conditioning, heater, computer, night lights, and several other " dangerous" items on at all times. Good thing my neighbor is a fire fighter.
I just finished reading this entire thread. You've described your experiences using class D amps in your system as:
"
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." "
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.""Also....am I crazy or is this amp casting an unstable image? Like sounds don't want to focus and stay there." Like....the vocalist says a word that happens a little to the right, but the trailing consonant finishes a little on the left.""Damn, 24 hours later and this amp sounds like trash -- rolled off / recessed mids again, soundstage depth almost gone...wow. I guess this thing with wired class D burn-in is true.
"
You seem to attribute all of the above to the class D amplifiers and you've received replies affirming these perceptions of the poor quality of class D from the herd of Audiogon usual suspects of class D naysayers that reliably chime in on most threads mentioning class D. Of course, the naysayers chiming in their aspersions was not surprising but, not being aware of you being similarly afflicted with their knee-jerk anti-class D bias, I was very surprised to read of your negative results. I have no experience or knowledge of the Teac class D offerings but I do for the D-Sonic and several other companies' class D offerings. As a user of 3 different class D amps over the past 3 years (The ClassDAudio SDS-440-CS and the Emerald Physics Ep-102 stereo amps as well as a pair of D-Sonic M3-600-M monoblock amps) in my system driving Magnepan 4 ohm speakers, I find it hard to believe the D-Sonic M3-800-S amp is performing so poorly in your system.
Even straight out of the box, I would expect the main attributes of the D-Sonic M-800-S amp to be immediately and obviously apparent; very good bass response and control, extremely low noise floor, very good dynamics with a smooth and neutral mid-range and treble that is also very detailed without any hint of brightness or harshness, In my experience with the D-Sonic monos, that use Anaview/Abletech modules rather than the Pascals in your amp, there was a reasonable break-in period but I recall them sounding very good immediately and then proceeding to improve mainly in the mid-range and treble detail and smoothness over the first few weeks. You not getting similar results in your system suggests to me that there may be another culprit or culprits responsible in your system. There are several possibilities: your left and right speakers may not have been properly matched at the manufacturer, you have 1 or more drivers blown/not performing to original spec or your D-Sonic amp is not functioning up to spec.
There are a few methods to narrow down any issues that may exist: 1. Bring your D-Sonic amp to a friend's or dealer's and test it out with their speakers/system. 2. Borrow a friend's or dealer's amp that you can verify is working properly and determine if the sound differs. 3. Take your speakers to a friend or dealer and connect them to their amp ,that they can verify is functioning properly, and determine if the sound differs. #1 will identify whether your D-Sonic amp is the culprit and #2 or #3 will identify whether your speakers are the culprit. I think trying #1 and then #2 sequentially would likely be the most efficient, least laborious and sufficient method to identify exactly what is causing your system's poor performance. If the amp continues to under-perform, I'd suggest contacting D-Sonic's owner, Dennis Deacon, about your issues. He's very knowledgeable, reasonable and fair. If you go through this method, please post your results. If you're accepting wagers, please put me down for $5K straight-up on your speakers being the culprit.
A final friendly tip: If you try your D-Sonic in a friend's system, don't expect it back without a struggle.
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.
I may be able to add a very slight addition, to the volumes written here. Leave them on, or at least let them warm up well-longer than you'd expect for a solid state piece of gear. LIke, a couple hours. Think of tubes x2.
I'm a Jeff Rowland 501-pair owner. They were early serial number 501's and I had a catastrophic power event over New Years (2017) which cause both to crater. (let's just say, imagine your heart rate and stomach acid level when you realize both your Rowland amps are door stops....) ANYWAY - after a call to Jeff himself, and lest I digress, he's a true gentleman and engineer with SUPERB CUSTOMER SUPPORT even with amps bought used. Anyway: I had two new amp modules coming my way. The old ones were ICEpower 1000ASP, revD. The new ones were ICEpower 1000ASP rev J. Indeed, Jeff uses an input stage consisting of a Furman transformer, but the rest of the amp is the ICEpower ASP module - and I don't know, nor anyone maybe, if it's "Plain Jane" or "Jeff's Secret Sauce". What I can say about the "new versus old" is the Rev J modules (circa 2016 ish ?? I don't really know) sound better than the Rev D boards (circa mid 2000's?), and that's even before the Rev J's are really broken in. 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). I'm now in that painful process with my new modules "brand spankin' new" - still not there yet (as I can't just let them run, right now: in May I will be able to. Family stuff. I digress, again) however I can attest to the break in time....but I want to add, and I haven't seen it posted yet - leave those suckers ON, or at least get them warm for a few hours before critical listening.
To the astute reading this, you may have caught the dichotomy of "catastrophic power event" and "need to leave them on all the time". Yep. The need to leave them on led them to their demise. I have since installed an isolation transformer and voltage monitoring circuit. I do see myself turning them off for longer periods of non-use. Also - I will be installing PC-1's as another line of protection, as well as (hopefully) some sonice benefits, but they sure sound good as-is.
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...
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