Topping B100 Amplifier Review

[Limopard]

Nice one, but the Fosi C3 deliver more power for half the price. Of course they are a bit noisier, but unless you press your ears against the tweeters it shouldn't matter too much. Still, for those who don't like class D amps it's a decent alternative.

 

[mhardy6647]

But how do you think these super capacitors are charged?

 

[mhardy6647]

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.

Transient Intermodulation Distortion (i.e., TIM*) was the bugbear that hk was on about in those days.

https://hifisonix.com/wp-content/uploads/2017/10/The-Theory-of-TIM-Matti-Otala.pdf

______________
* With, of course, no offense meant to our own @Timcognito!
EDIT: nor, of course, to the Wizard Enchanter Tim.

 

[Timcognito]

Transient Intermodulation Distortion (i.e., TIM*) was the bugbear that hk was on about in those days.

https://hifisonix.com/wp-content/uploads/2017/10/The-Theory-of-TIM-Matti-Otala.pdf

______________
* With, of course, no offense meant to our own @Timcognito!
EDIT: nor, of course, to the Wizard Enchanter Tim.
View attachment 393122

None tak'in, and being the butt of good spirited joke or prank is okay too.

 

[Timcognito]

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.

All true and in the US willfully building a copy to see if works is illegal also. Now the rub comes if one follows the specification builds it and it doesn't work as one suspected. Then there is an obligation to file an invalidation claim with the USPTO.

 

[Limopard]

But how do you think these super capacitors are charged?

Something with a lightning and a DeLorean, I suppose.

 

[Waxx]

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:

View attachment 393049

It's not about that that people complain, but about the support and repairability of this amp, and about the form factor. 100dB sinad or 125, it does not matter in reality as both are unhearable. So now they can do that, focus on build quality, support and maybe also a bit design as this little bland black box is not so fun to look at.

 

[terryforsythe]

Then there is an obligation to file an invalidation claim with the USPTO.

There is no such obligation of which I am aware. That said, anyone can request a re-examination of a patent at any time during the period of enforceability of the patent. But, see:

37 CFR 1.906 Scope of reexamination in inter partes reexamination proceeding.

• (a) Claims in an inter partes reexamination proceeding will be examined on the basis of patents or printed publications and, with respect to subject matter added or deleted in the reexamination proceeding, on the basis of the requirements of 35 U.S.C. 112. (Underlining added).

With regard to ex parte review:

• (a) Claims in an ex parte reexamination proceeding will be examined on the basis of patents or printed publications and, with respect to subject matter added or deleted in the reexamination proceeding, on the basis of the requirements of 35 U.S.C. 112. (Underlining added).

Thus, only when subject matter is added or deleted during the review proceeding are patents reviewed under 35 U.S.C. 112, which pertains to the enablement and written description requirements.

 

[amirm]

It's not about that that people complain, but about the support and repairability of this amp, and about the form factor. 100dB sinad or 125, it does not matter in reality as both are unhearable. So now they can do that, focus on build quality, support and maybe also a bit design as this little bland black box is not so fun to look at.

It is unfair to keep complaining about these areas without any facts. You are welcome to wait until more data comes in on its reliability but not keep sewing doubt about it just because.

 

[Timcognito]

There is no such obligation of which I am aware. That said, anyone can request a re-examination of a patent at any time during the period of enforceability of the patent. But, see:

37 CFR 1.906 Scope of reexamination in inter partes reexamination proceeding.

• (a) Claims in an inter partes reexamination proceeding will be examined on the basis of patents or printed publications and, with respect to subject matter added or deleted in the reexamination proceeding, on the basis of the requirements of 35 U.S.C. 112. (Underlining added).

With regard to ex parte review:

• (a) Claims in an ex parte reexamination proceeding will be examined on the basis of patents or printed publications and, with respect to subject matter added or deleted in the reexamination proceeding, on the basis of the requirements of 35 U.S.C. 112. (Underlining added).

Thus, only when subject matter is added or deleted during the review proceeding are patents reviewed under 35 U.S.C. 112, which pertains to the enablement and written description requirements.

Result of reexamination can be removing the patent because it is invalid if indeed it does not support its claims or "improper formation" it doesn't work as described, being one. But usually there is litigation disputing its invalidity. Reexamination is usually the first step. Yes, obligation is too strong for something that one should not have done, building someone else's patented device.

 

[ryanmh1]

These amps' behavior into a particularly reactive load (e.g., a Quad ESL-57 loudspeaker --or connection to most any loudspeaker via a Polk Audio "Cobra Cable", both well documented killers of marginally stable amplifiers) might be interesting to study.

True, but I suspect they're fine, hence the difficulties measuring high powers. It seems like the protection is probably quite aggressive. The protection kicking in and shutting down measurements is a (necessary) theme with amplifiers featuring vanishingly low high frequency distortion. I wouldn't worry about it too much. There's lot of unsubstantiated(?) scuttlebutt about manufacturer reliability, but those are likely not design issues, if even accurate and not just Internet amplification of a few loud voices.

Still, I think what the world needs is a Topping/Tonewinner collab. The performance of this thing (well, some simulacrum of it) tucked into a TW AD-2500 "Topping Edition" would be a hot ticket. This is great, but just think about it. Solid OEM experience combined with a circuit design that's actually good. I think a lot of people would pay a few hundred bucks more for one of those things versus their current prices just to have John Yang and Topping spend a week redesigning it. That's unexplored territory and a market niche to be claimed. [Heck, I don't care. Even convince US based Monoprice Monolith/ATI to let them tinker with those things, which are probably faultless, but dangit .03% THD at 20kHz.. Gimme that flat line at .003% so I don't have to needlessly wonder!] Few designers seem to have explored and become as adept at proper feedback in a marketable, stable product as Topping. Combine that with high power (500W into 4 ohms, mmkay?), big toroid (I know, noise, but who cares!), giant meter(s), flat distortion under .003%(ish) across the board, unflappable reliability, and (with a few more output transistors tacked in) stable into 2 ohms. Boom. All around $2000 (adding in some $$ for the upgrades/design time). It's the amp I think a lot of us want to power our big giant towers, but literally no one sells.

And for goodness sake, just drop this patent nonsense. It's dumb. No one has the first clue.

 

[EddNog]

Yeah, really. Is this Audio Science Review or is this Audio Patent Review?

-Ed

 

[terryforsythe]

Result of reexamination can be removing the patent because it is invalid if indeed it does not support its claims or "improper formation" it doesn't work as described, being one.

Please provide a citation to support that statement. It is contrary to what is specifically stated in the M.P.E.P., the pertinent passages of which I quoted above.

 

[Timcognito]

Please provide a citation to support that statement. It is contrary to what is specifically stated in the M.P.E.P., the pertinent passages of which I quoted above.

No not an attorney and I brought up invalidity. Reexamination usually involves what the patent office used or didn't look at to issue the patent. Invalidity has to whether what is in the issued patent is novel, published, justified or device will work etc. The fact that my subject was changed does not commit me to post about something else. My premise was that one should not build a another inventor's patented device unless one thinks it will not work the way is shown in the patent. If it does not, that patent can be found invalid. I do want to ague over something that just hijacks the thread, especially since I am not an attorney, but did spend two years on a team that won an invalidity trial having to do with something that would not work as patented, again off topic. No offense, sorry if I misread your earlier post and I am more interested in Class B amplification.

 

[terryforsythe]

Result of reexamination can be removing the patent because it is invalid if indeed it does not support its claims or "improper formation" it doesn't work as described,

Please provide a citation to support that statement. It is contrary to what is specifically stated in the M.P.E.P., the pertinent passages of which I quoted above.

@Timcognito, FYI, I doubt you will be able to find a supporting citation.

1. Below is the entire section of the CFR, 37 CFR 1.906, pertaining to the scope of inter partes reexamination:

§ 1.906 Scope of reexamination in inter partes reexamination proceeding.

(a) Claims in an inter partes reexamination proceeding will be examined on the basis of patents or printed publications and, with respect to subject matter added or deleted in the reexamination proceeding, on the basis of the requirements of 35 U.S.C. 112.

(b) Claims in an inter partes reexamination proceeding will not be permitted to enlarge the scope of the claims of the patent.

(c) Issues other than those indicated in paragraphs (a) and (b) of this section will not be resolved in an inter partes reexamination proceeding. If such issues are raised by the patent owner or the third party requester during a reexamination proceeding, the existence of such issues will be noted by the examiner in the next Office action, in which case the patent owner may desire to consider the advisability of filing a reissue application to have such issues considered and resolved. (Emphasis added).


2. Below is the entire section of the CFR, 37 CFR 1.552, pertaining to the scope of ex parte reexamination:

§ 1.552 Scope of reexamination in ex parte reexamination proceedings.

(a) Claims in an ex parte reexamination proceeding will be examined on the basis of patents or printed publications and, with respect to subject matter added or deleted in the reexamination proceeding, on the basis of the requirements of 35 U.S.C. 112.

(b) Claims in an ex parte reexamination proceeding will not be permitted to enlarge the scope of the claims of the patent.

(c) Issues other than those indicated in paragraphs (a) and (b) of this section will not be resolved in a reexamination proceeding. If such issues are raised by the patent owner or third party requester during a reexamination proceeding, the existence of such issues will be noted by the examiner in the next Office action, in which case the patent owner may consider the advisability of filing a reissue application to have such issues considered and resolved. (Emphasis added).

(d) Any statement of the patent owner and any accompanying information submitted pursuant to § 1.501(a)(2) which is of record in the patent being reexamined (which includes any reexamination files for the patent) may be used after a reexamination proceeding has been ordered to determine the proper meaning of a patent claim when applying patents or printed publications.

 

[pablolie]

If I had to pick a career path all over again, it'd be being a patent lawyer in Silicon Valley... :-D

 

[billou5767]

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.

excuse i speak for french / europe law

 

[billou5767]

It is unfair to keep complaining about these areas without any facts. You are welcome to wait until more data comes in on its reliability but not keep sewing doubt about it just because.

with 30 / 40 year of hifi experience with the photo of inside pcb , maker , component , motherboard we see if just , above or under street price and reliability

 

[terryforsythe]

Reexamination usually involves what the patent office used or didn't look at to issue the patent.

Yes, with regard to 35 USC 102 (novelty) and 35 USC 103 (obviousness). However, 35 USC 112 (enablement, written description, etc.) only is considered "with respect to subject matter added or deleted in the reexamination proceeding".

 

[Timcognito]

@Timcognito, FYI, I doubt you will be able to find a supporting citation.

1. Below is the entire section of the CFR, 37 CFR 1.906, pertaining to the scope of inter partes reexamination:

§ 1.906 Scope of reexamination in inter partes reexamination proceeding.

(a) Claims in an inter partes reexamination proceeding will be examined on the basis of patents or printed publications and, with respect to subject matter added or deleted in the reexamination proceeding, on the basis of the requirements of 35 U.S.C. 112.

(b) Claims in an inter partes reexamination proceeding will not be permitted to enlarge the scope of the claims of the patent.

(c) Issues other than those indicated in paragraphs (a) and (b) of this section will not be resolved in an inter partes reexamination proceeding. If such issues are raised by the patent owner or the third party requester during a reexamination proceeding, the existence of such issues will be noted by the examiner in the next Office action, in which case the patent owner may desire to consider the advisability of filing a reissue application to have such issues considered and resolved. (Emphasis added).


2. Below is the entire section of the CFR, 37 CFR 1.552, pertaining to the scope of ex parte reexamination:

§ 1.552 Scope of reexamination in ex parte reexamination proceedings.

(a) Claims in an ex parte reexamination proceeding will be examined on the basis of patents or printed publications and, with respect to subject matter added or deleted in the reexamination proceeding, on the basis of the requirements of 35 U.S.C. 112.

(b) Claims in an ex parte reexamination proceeding will not be permitted to enlarge the scope of the claims of the patent.

(c) Issues other than those indicated in paragraphs (a) and (b) of this section will not be resolved in a reexamination proceeding. If such issues are raised by the patent owner or third party requester during a reexamination proceeding, the existence of such issues will be noted by the examiner in the next Office action, in which case the patent owner may consider the advisability of filing a reissue application to have such issues considered and resolved. (Emphasis added).

(d) Any statement of the patent owner and any accompanying information submitted pursuant to § 1.501(a)(2) which is of record in the patent being reexamined (which includes any reexamination files for the patent) may be used after a reexamination proceeding has been ordered to determine the proper meaning of a patent claim when applying patents or printed publications.

I was talking about patent invalidity and often reexamination of how the patent was issued is a ONE step in proving invalidity.

Yes, with regard to 35 USC 102 (novelty) and 35 USC 103 (obviousness). However, 35 USC 112 (enablement, written description, etc.) only is considered "with respect to subject matter added or deleted in the reexamination proceeding".

Yes but focuses on what the examiner did or did not or review or should have used to issue the patent and not weather the device will work, that is the obligation of the inventors in the specification. I was referencing patent invalidation of something that will not function as specified.