Can you believe Chinese specs ? - Page 1
Forum section: electronics / general

author: bilko
author_rank: Frequent Contributor
timestamp: May 31, 2011, 07:46:52 pm
content: Here is one I came across earlierSpecification:12 Volt powered.Speaker is 18cm long and 11cm height60W Speaker provides very loudly sound,it is about 300 decibels unit at full volume.5 Siren sounds: Hooter/Ambulance/Traffic/police/Fire alarmMicrophone for PA system.http://cgi.ebay.co.uk/CAR-AMPLIFIER-ALARM-12V-PA-SPEAKER-SYSTEM-MIC-5-SOUND-/280676419988?pt=Car_Speakers&hash=item41599e4994That certainly would make my ears bleedThe amount of rubbish claims that these manufacturers are making is unbelievableAnother one, 1000W computer speakers, uses 6v 300mA plug top transformer.Anybody else found other blatant false claims ?

author: tekfan
author_rank: Frequent Contributor
timestamp: May 31, 2011, 09:10:59 pm
content: Quote from: yachtronics on May 31, 2011, 07:46:52 pmYeah right. Not even a stick of TNT can achieve that kind of pressure level.

author: bilko
author_rank: Frequent Contributor
timestamp: May 31, 2011, 09:27:38 pm
content: Quote from: tekfan on May 31, 2011, 09:10:59 pmNot even the largest nuclear bomb ever detonated can beat this gadgetdB282 (N)NUCLEAR BOMB, 57 MEGATONS HYDROGEN LARGEST EVER DETONATED, 1961Here is an interesting list of dB SPLhttp://makeitlouder.com/Decibel%20Level%20Chart.txt

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: May 31, 2011, 09:43:10 pm
content: I would prefer the title to was written by pointing out the Fake specs , than China it self.On topic ..Other than the words of the seller , what is also important , are the educated buyer .Usually I do not blame the seller , only the buyer.But I can not blame my self when I got :1) bad machined step-up rings for my camera . ( got refund but it took me some time)2) third grade or lower quality of dust filters for the fans of my computer. ( got refund but it took me some time)3) universal charger for every mobile phone battery + PDA ( also third grade or lower quality ) ,got a promise to receive an healthy unit , that never came , so I opened and repaired the bad one who I originally got,with 42 days delay .And the point is that this happens when you buy products from the basket in the street,with out actually be there !! Just by looking a picture.The point is that there is some people out there , who are selling their trash ( garbage ) ,by using the ebay channel.I have also find , good and respectable Chinese people , who haves only first quality items on display,and found genuine Japanese parts ( UV filters for digital cameras) or original Sanyo batteries for my video camera ,at half price or less.Not to say that there is no way to go wrong if you get any UNI-T products.About 100 years back in USA , there was sellers who was had on sale bottles of medicine for every disease,just 1$ per bottle ..They did have customers too.But the Chinese people was safe , because they was lots of thousands of kilometers away ...And ebay was not active yet .

author: Mechatrommer
author_rank: Super Contributor
timestamp: May 31, 2011, 09:56:46 pm
content: world record audio competition is at 180++ db, thats enough to bleed your nose. 300db you can be dead.

author: bilko
author_rank: Frequent Contributor
timestamp: May 31, 2011, 10:12:12 pm
content: Quote from: Mechatrommer on May 31, 2011, 09:56:46 pmDefinitely would be dead@Kiri, that was one example, quite obvious for somebody with a little knowledge.What about the spec for a DMM, costs $85 inc. shipping, 0.05% +/- 1 digit accuracy. Can you trust this spec or is this another fabrication ?

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: May 31, 2011, 10:22:18 pm
content: About the matter of trust, ask all those people who had pay 1$ for a bottle of medicine for every disease.Speaking about multimeters , the numbers says that the 88% of the noobs , they will fail to get an good unit as their first multimeter.When they will get out to get their next one, they almost know what they need or what to believe.

author: ziq8tsi
author_rank: Regular Contributor
timestamp: May 31, 2011, 11:27:33 pm
content: Quote from: Kiriakos-GR on May 31, 2011, 09:43:10 pmIndeed. It should be "can you believe eBay specs". And the answer to that is more complex and more interesting.In this case it seems that the seller has a good reputation because neither he nor his target market have much idea about the claims he is making.Even in this thread, nobody has pointed out that "300 decibels" is simply a ratio of 1030:1. It says nothing about loudness without a means of measurement and a reference level to compare it against.On any of the standard scales of measuring sound, 300dB would be impossible without distortion because it would require rarefactions in the sound wave to have a pressure less than that of a vacuum.Because he has not specified a reference level, the seller's 300dB claim could even be correct. But more likely, both he and his buyers think that it means three times as loud as 100dB, which is the unreferenced value that journalists generally quote as that of a pneumatic hammer. But three times that would actually be 104.77dB.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: May 31, 2011, 11:54:14 pm
content: Well I have an announcement to make .I am not the only one who vandalizes the English language ,in order to communicate with all of you ..I have see lots of problematic translations on Ebay ,descriptions & pricing .Example: 20 male bananas for 1000$ instead of 10$ .About the electrical specs , there is another chaos about them.Most of the people who write the descriptions ,they do not have any idea about electronics.They just get payed to do the job , and they copy-paste blindly ,generic descriptions that was given to them by the whole seller.

author: the_raptor
author_rank: Regular Contributor
timestamp: June 01, 2011, 12:26:16 am
content: Since when can you believe speaker specs in general? With audiofools and the ignorant being the main market speaker specs have been complete bullshit for decades (ie listing peak power that they could sustain for 1 femtosecond without the small print).

author: bilko
author_rank: Frequent Contributor
timestamp: June 01, 2011, 12:53:11 am
content: Quote from: the_raptor on June 01, 2011, 12:26:16 amSomebody once told me that gold plated audio leads sound better and that they could definitely hear the difference

author: Kuolas
author_rank: Contributor
timestamp: June 01, 2011, 01:00:46 am
content: I've seen brand name HiFi who says 800W RMS and it's powered by a 80W PSU... What's going on in audio these days?

author: the_raptor
author_rank: Regular Contributor
timestamp: June 01, 2011, 01:07:39 am
content: Quote from: yachtronics on June 01, 2011, 12:53:11 amWell gold plated connectors are a more electrically reliable connector (rusted/corroded connectors are prone to higher noise). That is why every serious piece of electronics uses them.The audiofool stuff is when it is cables for digital protocols. Or the gold is in the shielding etc.

author: saturation
author_rank: Super Contributor
timestamp: June 01, 2011, 01:15:03 am
content: Sometimes, some Chinese product ads may simply be poor translation from Chinese to English.In electronics test equipment specs, its variable. Rigol certainly has been truthful for as long as I can recall reading its advertising.Uni-T specs are error prone at least by several user test reviews posted on eevblog.The Hantek 3x25 FG spec sheet is poorly written and incomplete, but the testing we gave it shows its better than what even Hantek has written about it.Thus, in toto its difficult to go by the spec sheet from a brand with a lesser known reputation. Its one reason I hope folks review their purchases here, to confirm the devices capacities.Quote from: yachtronics on May 31, 2011, 10:12:12 pm

author: bilko
author_rank: Frequent Contributor
timestamp: June 01, 2011, 01:21:40 am
content: Quote from: saturation on June 01, 2011, 01:15:03 amTotally agree, good comment.

author: CircuitMart
author_rank: Contributor
timestamp: June 01, 2011, 09:16:02 am
content: I once was blamed and laughed in a UK forum because of the use of "wanna".They call it a lazy slang....I supposed to express in oral English and I indeed make a mistake as it comes from American English....English is important before selling products. I always believe that...Iris

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: June 01, 2011, 09:27:21 am
content: Quote from: yachtronics on June 01, 2011, 12:53:11 amPartially its true , in theory every low resistance connection between the amplifier and the speaker,causes less loss in the high frequencies .But you must have first, very high quality of speakers at the price range of 1500$,so to be able to spot such differences.Many respectable brands makes amplifiers with gold plated terminals !!But very few are buying worthy speakers .Once I came close enough to get an top ranked 3 Way Speaker set from B&W ,it was used as reference speaker system, for every sound test.But I did not got it , and now ( many years later ) , I think that I did the right move.Speakers get damaged even with out playing at all.( humidity or sun rays can kill them, or even the membrane it self has an limited life. )

author: CircuitMart
author_rank: Contributor
timestamp: June 01, 2011, 09:28:55 am
content: A seller can not always give his own margin, namely cut his price in an unlimited manner.if that, there must be a reason....

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: June 01, 2011, 09:53:04 am
content: Few messages above ,I had wrote about one of my experiences about : third grade or lower quality of dust filters for the fans of my computer.The all story is as follows .a ) I found those filters in Germany , packed nicely in bags , and the pricing was not bad .b ) I added many more items in that order in Germany , because the shipping cost was high for just getting four fan filters.c ) The seller did not had one of my items in stock , and set an Hold in all of it , for more than two weeks.d ) I got upset and buy the same fan filters from the cheapest source in China ( totally identical - from the same manufacturer).f ) The German seller , finally found his way and send my items , all of them .The filters that came from Germany was perfect in all .The same filters that came from China , was had production defects , and it was full of scratches.This is what you get for 1.50 $ per item , shipped and all .The price in Germany was four times higher , with out shipping.But I did got an product as pictured .

author: Unknown
author_rank: Unknown
timestamp: June 01, 2011, 09:55:03 am
content: Slightly off-topic, but fits well with the whole concept of manipulating the customer.I saw a 200W PIR floodlight retrofitted with a 150W halogen lamp and a green sticker on the front saying they were able to make the floodlight 25% more energy efficient.A year on still brings a smile to my face when I think about it...

author: Arthur
author_rank: Contributor
timestamp: June 01, 2011, 11:16:02 am
content: You get a lot of the same kind of nonsense with computers on eBayA lot of sellers are banking on people failing to understand that the clock rate of a multicore processor is not the sum of the clock rate of each core, so they will say things like, "This system has a 7.2Ghz CPU" well hot-dog, it must be great in that case!I also see people deliberately quoting capacities in megabits or gigabits as opposed to the bytes that consumers are familiar with. Then people wonder why the flash drive they get is 8 times smaller than they expected.So even when specs are technically correct, they can still be deceiving.It's not a Chinese problem, it is a marketing problem. This is why most people hate marketeers. Give them an inch and they will take an inch, then come back to steal your car.

author: Mechatrommer
author_rank: Super Contributor
timestamp: June 01, 2011, 11:33:55 am
content: Quote from: Arthur on June 01, 2011, 11:16:02 amyou will be lucky if you dont have two big bolt nut inside.https://www.eevblog.com/forum/index.php?topic=3084.0

author: Arthur
author_rank: Contributor
timestamp: June 01, 2011, 12:00:35 pm
content: Yeah, I certainly hope the people who bought that drive weren't conned into paying full price for it.The more things I buy, the more I realise "you get what you pay for" is true.Now I will pay the asking price for a quality product, even if I feel it is a bit of a rip off. Trying to save money by buying cheap products, particularly electronics, always ends up being a false economy in the end.People might call me a sucker when they see the receipt, but they won't be calling me a sucker a decade later when my stuff still works (hopefully!).Of course there are a lot of things I can't afford, and in that case I will simply go without rather than buying a crap product. Every day when I go to work I see what life is like when all your equipment is cheap junk. I don't want life to be like that when I'm at home as well.

author: Mechatrommer
author_rank: Super Contributor
timestamp: June 01, 2011, 02:18:17 pm
content: Quote from: Arthur on June 01, 2011, 12:00:35 pmvery true.