Clipping as in reaching max output voltage? The protection triggers way earlier, at less than 12 V RMS into 4R, which is about 34 V pp
It seems to be load dependent, and I don't know the source of your statement or I missed it. 🙂
However, for what it's worth, the following are related measurements from ASR website
I hope I haven't come across as being 'angry' at Topping or those that use similar measurement techniques. My discussion is more around the lack of (at least that I can find) some kind of 'world' standard for measuring and reporting (NOT RATING) data for amplifiers and loudspeakers. Since EdGr kindly reminded me that the US does in-fact have a standard set forth by the FTC in 16CFR, I was curious if these amplifiers and their associated claims would pass muster here in the US.
As an example, to a common consumer, they may think that the B100 is 'suitable' for a "4 ohm" speaker they want to purchase => Tekton DI as one example.
They may further think that because the DIs are 'so sensitive' that they could reach ear-splitting levels in a big room when using these cute little amps that conserve so much energy over some big ol' Class A amps.
What they don't know is:
- the impedance characteristics of the speaker (not commonly shown, and why would an average consumer need to care) over the frequency range
- how long those amps can provide that power without going into protection.
That's the tricky part. I've never questioned that what Topping (or ASR) claims is accurate. What I've said is that I think they're careful. Without specifically noting what test methodology is used (some people use a little asterisk and notes) - how is a consumer or anyone else to 'really' know how the amps perform. All the average consumer would tend to do is "compare specs". Well, if the measurement technique is different across the world for advertising / reporting a spec, then no meaningful comparisons can be made. I suppose that is one good reason for ASR or magazines or ... whomever. At least when they measure equipment, they do it consistently (or so we'd hope). So, at least within that one publication, people can make meaningful comparisons.
I agree. 🙂
Again - I find these amps to be interesting. I'd still get my money back if it were easy. I'll still not try the B200 b/c I now think I know how Topping reports their results, and even the B200 may not work for me. They're too hard to return if I don't want/need them, and they're too expensive to just toss the money. Again, a plug for your local hifi dealer.
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Separate from above - Since ASR is "US-based" as best I can tell, I do wonder 'aloud' why they don't use the FTC standard measurements as part of their protocol. 
There was quite some discussion about this in the ASR thread. You get those high power levels only for very short bursts. Amir apparently uses only 20 ms long bursts, which is less than the cycle time at e.g. 30 Hz. Pavel used 800 ms bursts. I used continious sines which the amplifier is supposed to sustain for 5 minutes. In my case, about 2 minutes at 10 V Rms = 28 V PP were fine, but going to 11.6 V tripped the protection within 2 seconds and permanently damaged the amplifier.
I was not aware of this and I wonder what the protection is for if then the amplifier gets damaged.
I can understand an engineering error, but this frankly seems a bit too much.
By the way, damaged in what way and part?
Furthermore, what was the purpose of such a stressful test?
Well, afterwards there was the 1 - 1 blink code, even after 2 h without power and completely cooled down and input and output disconnected. That code means abnormal supply voltage.
Stressful? 11.6 V RMS into 4 R is 33 W, so a third of rated power. The amp should be able to do 5 min of rated power, not 2 seconds of a third of rated power.
The purpose was trying to verify PMA's test result. I was uneasy about reports by PMA and Itsall... about the amp going into protection repeatedly during normal listening, so I wanted to figure out if this amp is useful for any of my applications.
Okay okay, as I said I was unaware or missed that you had that amp and assumed the test was stressful without going into much more detail also because I believe that your test is not comparable with a real musical signal and therefore I wonder what its purpose would be.
Anyway, maybe you've said this before and I missed it, but wouldn't it have been easier to just say it instead of asking a lot of questions you already knew the answer to?
It's not hard to guess that you consider this amplifier to be junk.
I, on the other hand, despite everything, still don't.
Capslock is certainly more than capable of clarifying their own intent. However, I never once saw them say that the amps were "junk".
Personally, separately from Capslock, my only 'issue' is that the amplifiers don't perform in a similar fashion to other "100W" amplifiers I own or likely could have purchased instead of the B100s.
Since there does not seem to be any sort of a 'global' standard for power measurement that is accepted across the industry, it can be challenging for an uneducated consumer to make a choice via 'spec comparisons'. Since "wattage" is likely to be the #1 advertised selling point of an amplifier, it sure would be nice if there was a more unified standard for its measurement and reporting.
Personally, separately from Capslock, my only 'issue' is that the amplifiers don't perform in a similar fashion to other "100W" amplifiers I own or likely could have purchased instead of the B100s.
Since there does not seem to be any sort of a 'global' standard for power measurement that is accepted across the industry, it can be challenging for an uneducated consumer to make a choice via 'spec comparisons'. Since "wattage" is likely to be the #1 advertised selling point of an amplifier, it sure would be nice if there was a more unified standard for its measurement and reporting.
Please note that the way you send your comment (which you posted right after mine) without using the Forum quoting or addressing the correct member with the "@" char then it looks like you addressed your comment to me, while the member who did misunderstood the meaning of PMPO thinking it was a member instead of meaning "Peak Music Power Output" it's not me. 🙂
Furthermore, since it is no mystery that there is not exactly a positive flow between you and me, I kindly ask you to refrain from these provocative impulses of yours, using the forum's Quote function correctly otherwise someone, certainly not me, might think you did it on purpose. 😉
Thanks in advance.
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Yes, I think so too. 😉
I actually said "to guess" because his comments don't seem (I repeat, seem) like those of someone who is happy with that amplifier.
I may be wrong, of course. 🙂
Honestly I can not understand why some people still try to defend this product. Firstly, it does not get to the specs it advertised, which is 100W/4Ohms. Even when they reach near that 100W number, 86W/4 Ohms, it go to protection mode in very short time, which is bad and will not pass either IEC 60268-3 (for EU) or FTC (for US). Thirdly, it is a bad product for their targeted customer. Their typical customer will read ASR, own a 2way or small three way bookshelf speakers like Kef LS50, R3, ... or the likes with their sensitivity lower than 86dB/W and difficult impedance dips. With those kinds of speaker, if you push harder, protection mode will kick in. For me as an electronics designer, this one is a not a good product since a good product needs to work properly 95-99% of the time. A well-measured product is not a good product if they do not work.
It is a toy amplifier (in term of output power), but advertise as an adult amplifier. This is for me a huge red red flag about the integrity of this manufacturer. There is nothing wrong about a toy amplifier, like diyaudio Pass ACA or Schiit Aegir as they have their space in powering very high sensitivity speaker, but at least they are honest about it.
It is a toy amplifier (in term of output power), but advertise as an adult amplifier. This is for me a huge red red flag about the integrity of this manufacturer. There is nothing wrong about a toy amplifier, like diyaudio Pass ACA or Schiit Aegir as they have their space in powering very high sensitivity speaker, but at least they are honest about it.
Well, it is certainly the best measuring amplifier reviewed by Amir. And I am not just talking about 5 W, 1 kHz SINAD and HD. Even 15 kHz THD+N is excellent over the full power band, as are multitone and two-tone IMD. That is no small feat.
The problem is that measuring with sub-second bursts does not tell the full story. I probably would have kept mine in spite of reports of the protection kicking in with music since I would have used them to drive the sats through an active crossover. But the protection not protecting the amp for even a two second burst well within rated power took the cake. That is something that can happen easily during setup or when a kid plays with the volume knob. Not something I appreciate when the seller in China, only selling through Amazon, the manufacturer is also in China (meaning it needs to be sent to China for repairs) and when the warranty is only one year and I doubt I could fix the amplifier myself due to lack of schematics, sealed modules and a microcontroller that seems to remember the last fault condition with no known way to reset it. Since I was within the return period, I decided to save € 550 and a future headache.
I will acknowledge that mine might have been a faulty unit or that early production may have had problems that later runs did not have, but it was a risk I was not willing to take. I have several Topping PA5 and PA5 II and a Topping DM7 DAC which have never let me down, but I think the B100 is a potential lemon.
The problem is that measuring with sub-second bursts does not tell the full story. I probably would have kept mine in spite of reports of the protection kicking in with music since I would have used them to drive the sats through an active crossover. But the protection not protecting the amp for even a two second burst well within rated power took the cake. That is something that can happen easily during setup or when a kid plays with the volume knob. Not something I appreciate when the seller in China, only selling through Amazon, the manufacturer is also in China (meaning it needs to be sent to China for repairs) and when the warranty is only one year and I doubt I could fix the amplifier myself due to lack of schematics, sealed modules and a microcontroller that seems to remember the last fault condition with no known way to reset it. Since I was within the return period, I decided to save € 550 and a future headache.
I will acknowledge that mine might have been a faulty unit or that early production may have had problems that later runs did not have, but it was a risk I was not willing to take. I have several Topping PA5 and PA5 II and a Topping DM7 DAC which have never let me down, but I think the B100 is a potential lemon.
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^ I'm not sure about the EU, but the product is sold through many other avenues than Amazon. I did not buy mine through Amazon. I wish I had used their marketplace. In that situation, I could have simply boxed them back up and taken them locally for return through January. Silly me.
Not saying that to correct you, but only to add that nudge to other potential buyers that still are willing to consider these amplifiers... that they will potentially benefit from a no hassle return policy if they don't meet expectations.
I test my designs at full power into 8 and 4 ohms continuous and into 2 ohms for 2 minutes. For thermal performance, my class AB amps must deliver 1/3rd power into 8 ohms for 1hour and the temp of the heatsink at the end must not exceed 60 C. An amp that can only drive full power into a load for 50 or 100 ms is a toy. The Topping is clearly been designed to game the ASR test regime.
It’s s pity that we’ve imported ASR’s overemphasis on ppm distortion levels at the expense of every other important performance parameter into this forum. Why defend an amp like this?
As I remarked earlier, the Topping has a higher rating on ASR than the Benchmark ABH2. People laugh at the fact that an AudioNote amplifier that produces 20W at 10% distortion and costs $19000 gets a Stereophile ‘Product of the Year’ award. In my book, the Topping isn’t much better.
It’s s pity that we’ve imported ASR’s overemphasis on ppm distortion levels at the expense of every other important performance parameter into this forum. Why defend an amp like this?
As I remarked earlier, the Topping has a higher rating on ASR than the Benchmark ABH2. People laugh at the fact that an AudioNote amplifier that produces 20W at 10% distortion and costs $19000 gets a Stereophile ‘Product of the Year’ award. In my book, the Topping isn’t much better.
You're definitely an expert. I always value your opinion. If Topping (or ASR etc.) didn't publish specs noting the power ratings, or as an example, posted that they were (X)W into 8R using the testing methodology you use, would that be okay?
I suppose where I differ slightly, is that I don't consider that these amps are "toys" per se. They actually perform just fine in most situations (for me). I do, however, have a slight issue with the way Topping et. al. seem to come up with their "specs" that they advertise. These published claims or specs would potentially (likely) be in violation of US CFRs as I've come to understand them, but I am not sure how that works for products sold over the internet. I know if I had sold them (using the existing claims) at my previous company, we'd have had a serious issue to handle with the FTC.
In short - I don't know what specs they'd meet on your tests, but let's say... if they met 8W and were advertised as 8W, would you still have an issue?
There are "flea watt" amps that people hold dear. Who am I to say that they're not wonderful. My personal issue is that they (Topping) seem to "cherry pick" a test methodology that most suits the type of amp being produced to put it in the most favorable light. I'd never call it deception, but Topping doesn't tell the end-user (to the best of my knowledge) how those ratings were measured. So, I lean toward being mildly irked.
I suppose where I differ slightly, is that I don't consider that these amps are "toys" per se. They actually perform just fine in most situations (for me). I do, however, have a slight issue with the way Topping et. al. seem to come up with their "specs" that they advertise. These published claims or specs would potentially (likely) be in violation of US CFRs as I've come to understand them, but I am not sure how that works for products sold over the internet. I know if I had sold them (using the existing claims) at my previous company, we'd have had a serious issue to handle with the FTC.
In short - I don't know what specs they'd meet on your tests, but let's say... if they met 8W and were advertised as 8W, would you still have an issue?
There are "flea watt" amps that people hold dear. Who am I to say that they're not wonderful. My personal issue is that they (Topping) seem to "cherry pick" a test methodology that most suits the type of amp being produced to put it in the most favorable light. I'd never call it deception, but Topping doesn't tell the end-user (to the best of my knowledge) how those ratings were measured. So, I lean toward being mildly irked.
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@Bonsai
@ItsAllInMyHead
I appreciate both ways of thinking and informing non-experts (just like myself) about your knowledge and experiences, but also I would suggest asking Topping through an email (serviceATtpdz.net) replacing AT with @.
I've asked them for information about owned devices and they have always responded within a few days.
I would do this if the amp were mine.
At least if not only to learn about the design philosophy from manufacturer of this controversial piece of audio equipment.
@ItsAllInMyHead
I appreciate both ways of thinking and informing non-experts (just like myself) about your knowledge and experiences, but also I would suggest asking Topping through an email (serviceATtpdz.net) replacing AT with @.
I've asked them for information about owned devices and they have always responded within a few days.
I would do this if the amp were mine.
At least if not only to learn about the design philosophy from manufacturer of this controversial piece of audio equipment.
Come on man. This amp is designed to game Amir’s 5W sinad test. The design philosophy is clear.
Why would sending an email change anything?
Why would sending an email change anything?
A tiny heatsink inside the box without any notable air convection can not withstand 100W continuously from class B/AB output stage. Design philosophy cannot change physics.