Topping B100 Amplifier Review

[amirm]

I don't understand this assessment. You say you could not get above 86W@4ohm due to protection and also state it is rated for 83W. But the spec sheet you posted below it clearly states it is rated at 100W into 4ohn and 83W is into 8ohm (and is only a <10%THD) rating. However, your 8ohn test shows it clipped at 50W. In either case, your bench shows it failed to achieve its rated power out on the spec sheet.

You have to understand the measurement technique. I give two values to the analyzer: lowest output voltage to highest (which then becomes the input voltage to the amp). I also give the analyzer a step size and whether the sweep is linear vs log. The analyzer then measures in discrete points. What happens then is that there is not a ton of accuracy at the end of the sweep. We jump from one value to another. The points in between are not tested. In the case of B100, the step causes a shut down, and the previous does not. That gap is there and is responsible for a few watts of power.

To get around above issue, I run my max and peak powers with a rating of 0.1% THD. There, the analyzer searches for all output voltages that cause distortion to be 0.1%. Well that scheme does not work here as again, the B100 shuts down. So for vast majority of amplifiers, you should use this figure, the 0.1% THD for power rating which eliminates the above measurement restriction. In the case of B100, we can't and are stuck with inaccuracies of the measurements as I performed.

If one has enough time, or knows the exact input voltage as Topping would, they could arrive at the max power without the amplifier shutting down. Until then, you have to accept my power measurements of B100 to be approximate.

 

[Endibol]

Displays can also be operated for weeks and months using super capacitors.

But how do you think these super capacitors are charged?

 

[Waxx]

Technically there is nothing to remark on the amp, but i hate the form factor. I prefer all in one case, ceratinly for amps and a more solid standing device. This one will be pulled by the weight of cables very easely. But Topping always use those small cases it seems. And durability is always an issue with Topping.

I'll stick to my NCore based Audiophonics amps, they do the job good enough that their lower sinad won't matter already and the form factor is more my thing.

But technically this is as good as it gets i think.

 

[Haskil]

That external power supply for the monoblocks, which are supposed to be near the speakers, are a absurd design choice.

just imagine this amp being so close to the speakers that it was inside and suddenly it wouldn't be absurd anymore... there just needs to be a power outlet near the speaker and the amp like its power supply can be hidden behind the enclosure...
It's not that absurd

 

[Roland68]

But how do you think these super capacitors are charged?

...it was obvious that something super intelligent like this would come.
Why worry about unnecessary waste of energy, when your electricity comes from the socket...

 

[Sir Sanders Zingmore]

I don't. I did want to listen to it and might do that tomorrow and report back if that happens with my Salon 2 speakers.

Wondering if you had a chance to do this?

 

[Sokel]

If the product has a CE certification, it is not up to the seller to verify whether the product meets all the required parameters and characteristics. He is not even equipped to do so (see also for example the regulation against electromagnetic interference).

That's why I talked about good faith,as CE mark is a self-certification,something like a promise,it's not like an ENEC one.
Good thing is that the brick also have ETL certification.

 

[antcollinet]

If the product has a CE certification, it is not up to the seller to verify whether the product meets all the required parameters and characteristics. He is not even equipped to do so (see also for example the regulation against electromagnetic interference).

It's not up to the seller, but it is. up to the importer - which might be the same organisation in this case. But either way the importer is responsible in law for compliance with the regulations.

They would normally do this by review of test results and other compliance documentation.

Importers and distributors

Importers and distributors help ensure that only products compliant with EU rules, bearing CE marking are placed on the EEA market. As intermediaries between manufacturers and traders they must have knowledge of the legal requirements and ensure that products they distribute or import meet them.

single-market-economy.ec.europa.eu

See also - "Dealers who import" here:

Responsibility of dealers and importers of goods bearing a CE mark

www.dguv.de

 

[Esprit]

The second link concerns German laws, not European ones, and there too a limitation of liability for retailers is indicated, established by the European Court of Justice, which confirms what I have always written: if there is the CE marking on the product, the possible declaration of conformity, etc... the "seller" can sell the product without any worries because it is not up to him to verify any discrepancies between what the European regulations impose and the product he sells.
He only has to verify the documents and if the documents are correct (the CE marking is done through third-party companies that verify the samples sent to them by the manufacturers) he is also perfectly in order.
When products with counterfeit CE marking or that do not comply with European regulations are discovered by the competent authorities, all these products go to the shredder...

 

[terryforsythe]

but as usual in the land of audiophile old wives’ tales, the last bit magically "destroys the sound".

Harman Kardon claimed low negative feedback as a feature of one of its automotive audio amplifiers back in the mid 80's. They claimed that it resulted in lower IM distortion. Such marketing probably helped to promulgate that wives' tail.

 

[Roland68]

(the CE marking is done through third-party companies that verify the samples sent to them by the manufacturers)

The CE marking is always done by the manufacturer or the importer. A manufacturer can of course send their device to a company that checks everything, does the paperwork and also creates the CE declaration, but it is only unofficial, it is not on the documents and the company is not liable for anything.
But the manufacturer or the importer are liable for everything and they are also on the documents.

 

[welwynnick]

Check out this stunning performance in noise department at 5 watts and max power:
View attachment 392543
View attachment 392544

Some people may think this amp isn't noteworthy or remarkable, but Im not so sure, and looked more closely at the noise measurements.

I put together tables of some of the best performing DACs, power amps and headphone amps (because they have very useful high line level outputs). Topping generally lead the way.

They're all pushing test equipment limits, but the HPA tests at 50mV, and the amp tests at 5W, give a bit more insight. The dynamic range is lower, so it's easier to find the noise floor with an audio analyser.

The best HPAs (not in high gain mode) measure 93-94 dB SNR at 50 mV, which equates to a noise floor of around 1 microvolt. (L7 has tested a few with a preamp, and got over 100dB. )

Similarly, the B100 measured 131dB at 5W / 4.472V in low gain, which equates to 1.26 uV.

This is slightly better than the LA90 and B200, and much better than anything else.

Its also comparable to the best DACs, which at very similar voltage, are nudging 130dB @ 4V in ASR tests.

The best of the rest are around 10 uV.

Topping claim even better when tested with a low noise preamp (a technique they usually use with headphone amps) but note that this enhanced test is NOT used for their DNR claim of 151dB, which would otherwise be even higher:

 

[billou5767]

I have nothing against external PSU per see , but these plastic laptop power bricks ? Cooling simply can’t be great if it’s enclosed in an airtight plastic box ? If you build a better ventilated metal enclosure for the PSU you migth as well put it in the amp and save one box ?

Yes it’s easy to replace as you probably also need to , these things longevity are dubious.
Just like the old joke why some English houses have the plumbing on the outside, it’s easy to repair when it freezes

PSU and amp can be designed with the same longevity and service friendly design . Certification should be a normal thing to do for a serious manufacturer. I do see a problem when you have a very frantic product cycle if the product’s intended lifecycle is shorter than the time it takes for proper certifications , then I get the pre certified PSU ?

a lot of brick can have more 90/95% efficiency : cold

HP and other companies have been using such power supplies for workstation notebooks with much higher performance (230 watts and higher) for 20 years, without any problems. Defects are very rare and these power supplies are usually retired after 7-10 years with the notebooks. And we are talking about at least 8-10h/5d use, often even more.
So it is neither new nor untested.

In addition, such power supplies have an efficiency of around 94%, so that only a single-digit wattage of waste heat can be generated. In addition, the power supply of the B100 is well oversized so that it does not heat up much during operation.

The power supply is also used in the PA5/II (38v/3.2 or 4A), where it is subjected to a higher load and in my case, at high continuous power, it only gets hand-warm, no more.
Attached is a picture of the 3.2A power supply of the PA5 II, well built, components are OK and there is enough aluminum for cooling. If such a power supply only gets hand-warm even under heavy load in continuous operation, why shouldn't the plastic housing be sufficient?
View attachment 392804

external brick have in géneral good efficiency ( not hot) , in hifi its more easy for make no problem : heat , noise

my sony 55 inch have external brick 200/300 W i suppose ..most monitor have bricks

the real problem : the plug and compatibility

 

[billou5767]

The CE marking is always done by the manufacturer or the importer. A manufacturer can of course send their device to a company that checks everything, does the paperwork and also creates the CE declaration, but it is only unofficial, it is not on the documents and the company is not liable for anything.
But the manufacturer or the importer are liable for everything and they are also on the documents.

i confirm , that is a real problem with toy for child ( toxicity , danger ) with china toy CE mark

 

[Sean_S]

Incorrect. 35 U.S.C. 271 states:

(a) Except as otherwise provided in this title, whoever without authority makes, uses, offers to sell, or sells any patented invention, within the United States, or imports into the United States any patented invention during the term of the patent therefor, infringes the patent.

The question is, "Do they import or sell directly in the US?" I think only far east retailers distribute them in the US--even through Amazon.

This is the seller on Amazon--definitely not a US telephone number, but Chinese:

I would imagine this is a way to get around enforcement.

 

[billou5767]

Here:

View attachment 392861

Link also posted here.

It refers to both manufacturers and suppliers.
Of course an importer/supplier of thousands of products like Audiophonics may not know and there comes the good faith between them and the manufacturer.
Nevertheless,by law,they must know.

by law they cannot says they cannot know that , and have non responsability , its different

 

[terryforsythe]

The question is, "Do they import or sell directly in the US?" I think only far east retailers distribute them in the US--even through Amazon.

Well, I think it has been made abundantly clear that the patent that was discussed likely is not directed to the subject matter to which the person who mentioned it thought it was directed, so it is a moot point. Nonetheless, if a product made abroad infringes a U.S. patent still in force, the questions are:
1. Who is importing the product into the U.S.
2. Who is offering the product for sale in the U.S.
3. Who is selling the product in the U.S.
4. Who is using the product in the U.S.
Action can be brought against any and all of those entities. (Note that patent owners typically do not go after consumers because the damages they possibly might receive don't make it worth the litigation costs but, technically, they could do so if desired).

EDIT: Also note that, for foreign entities shipping infringing product from outside of the U.S. and that cannot be served, an avenue to stop sale of the product to entities in the U.S. is to file a complaint with the ITC.

EDIT 2: I suspect that Amazon would like to avoid becoming entangled in a patent infringement lawsuit, and would drop the sale of an infringing product from their website if they determine the lawsuit has merit. Heck, they may even drop a product immediately upon being notified of infringement to avoid the costs of paying patent attorneys to analyze the merit of the accusation, depending on how much revenue the product generates for Amazon. FURTHER EDIT: Amazon now has a process to remove patent infringing products from listing, and there is a dispute process that sellers can use if they disagree with accusations of patent infringement.

I would imagine this is a way to get around enforcement.

No. Re-read the statute I quoted.

 

[DanielT]

Harman Karden claimed low negative feedback as a feature of one of its automotive audio amplifiers back in the mid 80's. They claimed that it resulted in lower IM distortion. Such marketing probably helped to promulgate that wives' tail.

Add two more decades. Here is what it says in Harman Kardon HK670/2 owner's manual:

Low Negative Feedback
This unit has been designed to have low distortion and wide bandwidth without high negative feedback. This further improves its dynamic accuracy.

If 0.3% THD in 4 Ohm is considered to be low distortion? Who thinks so but Harman Kardon? Keep in mind that the amplifier was manufactured up to and including 2004, so this isn't an early/mid 1970s amp we're talking about here.

Harman Kardon HK670/2 Stereo Integrated Amplifier Manual | HiFi Engine

www.hifiengine.com

 

[terryforsythe]

by law they cannot says they cannot know that , and have non responsability , its different

With respect to liability, it doesn't matter whether an entity infringing a U.S. patent has knowledge of the infringement. They certainly will find out when a demand letter is received, and again so when a complaint is served. If there was prior knowledge of infringement, the infringer may be liable for higher damages, though.

 

[kyuu]

If 0.3% THD in 4 Ohm is considered to be low distortion?

That's the distortion at the rated power of 120W into 4 ohms. Some manufacturers use 0.1% THD, some use 0.5% THD, some use 1% THD, and some use whatever other value to determine the power rating in the spec sheet. It's arbitrary, really, and where they choose the cut off really has no bearing on whether the amp is "low distortion" in general.

Not that I buy that avoiding negative feedback results in low distortion. Those blurbs in the manual are certainly written by the marketing department.

Although I think both this and the whole discussion about patents and whatnot are getting rather off-topic for a review thread.