Topic Review (Newest First)
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| 10-01-2008 02:30 PM |
| martinharnevie |
Quote:
Originally Posted by Dogmann
My gripe with A2DP you have proved my point people are under the impression that a Stereo bluetotth headset will deliver a quality sound and currently it is far inferior to a wired solution and until it is as good why bother releasing it?
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A2DP was released in Bluetooth v2.0 since MP3 quality is good enough for most people, not the least since MP3 is the most popular file format.
Simple maths will demonstrate why CD/DAT level audio quality will not work with Bluetooth 2.0/2.1.
Bluetooth 2.0/2.1 has a raw bit rate of up to 4 Mbit/s (with EDR). With overheads and protocol redundancies this reduces to ca 1.5 Mbit/s for audio communication.
A CD or DAT player works with 44.1 kHz sampling, 18 bit resolution and 2 channels. 44,100 x 18 x 2 = ca 1.6 Mbit/s. In addition, you need a microphone channel for full duplex. This channel is typically not HiFi, but rather 12 bit resolution at 16 kHz sampling or thereabouts, i.e. 16000 x 12 = 192 kbits/s.
Hence, the total bandwidth requirement is ca 1.8 Mbit/s.
Even worse, a high end handsfree kit in a car needs 6 channels not 3. Why? Because the car needs to impersonate a headset seen from your phone for taking calls. And it needs to act as audio gateway to your headset, both for calls and the car's HiFi system. That's 2 x 2 HiFi channels in total. And in addition you have 2 microphone channels, one in and one out, which are not HiFi but still uses up ca 200 kbit/s each. So for the Bluetooth chip handling the handsfree function, the required bandwidth would far overshoot the available bandwidth in Bluetooth v2.0/v2.1.
If one or the other vendor has claimed otherwise, BT SIG should not be blamed for it. Unfortunately, there are vendors in these highly complex markets who oversell and underdeliver. But the facts from BT SIG have been available all the time.
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| 09-01-2008 07:45 PM |
| Dogmann |
@martinharnevie
They are not my dreams and wants but what was claimed Bluetooth would deliver, don't misunderstand i am not saying Bluetooth is rubbish or a failed technology not by a long way. But i stand by it has still not delivered half the things it said it was going deliver.
My gripe with A2DP you have proved my point people are under the impression that a Stereo bluetotth headset will deliver a quality sound and currently it is far inferior to a wired solution and until it is as good why bother releasing it? I've tried it but due to it's lack of quality have gone back to using a wired solution and as soon as Bluetooth can deliver an improved and comparable experience i will try it again.
Marc
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| 09-01-2008 06:06 PM |
| martinharnevie |
Hi Dogmann, with all due respect, I just cannot recognise or even relate those experiences of yours with my own experiences. They are entirely incompatible.
1. Unless you come up with a technology that can read your mind and understand and implement all your bodily desires, there is no such thing as "seamless" without the user spending some time configuring the system. And no matter what, this seamlessness have very little to do with BT, but rather the syncing application and the operating system. (BTW, I tell you what, with a test rig of an F2M03GLA BT module connected to a old Psion 5mx ~ ok it looks awful but it works ~, a Dell Inspiron 6400 on Windows XP and PsiWin, I've been running seamless syncing (as per your definition) for about a year now. )
2. With regards to the claim of incompatibilities between BT devices, I must say I just do not have anywhere near the kind of experiences you portray here. I'm just surprised how well and simple the 2 quid 'illegally BT' headset from an obscure manufacturer in China pairs with my Nokia 9300, my Dell Inspiron - for Skype calls - and my wife's P990. I'd say about a 100 different BT devices have passed my hands during the last 5 years and they've all work with one single exception. That's not saying i've not encountered problems, but at the end of the day, these problems have turned out to be more a matter of my sincere hatred of reading manuals - especially when they're written in chinglish - than any issues with the BT products per se. I can only conclude, somewhat unwillingly, that even the most awful BT products from the most obscure and 'unwanted' manufacturers still seem to work pretty well.
3. And what's the problem really with A2DP? It has been perfectly clear to everyone from day one that A2DP can only provide MP3 level audio quality with Bluetooth v2.0 and v2.1. I think there is a tendency for people to dream about CD/DAT quality, i.e. 44.1 kHz sampling, 18 bit resolution, and then blaming BT for not providing it. I think this is most unreasonable. It's been perfectly clear in the specifications that A2DP will not provide this. I've tried a number of products, both using my own company's A2DP BT modules and competitors A2DP BT modules, and i must say i'm generally pretty impressed.
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| 09-01-2008 02:53 PM |
| ares |
I use bluetooth for calls and stereo music every single day...i canīt live without it. I use it less for file transfers. Besides, i use it alot on my Nintendo Wii, for obvious reasons - btw the gaming market is really becoming huge for bt, because both Wii and PS3 use it on the controllers, headsets, etc
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| 09-01-2008 04:28 AM |
| Unregistered |
Quote:
Originally Posted by Dogmann
@martinharnevie
What i am talking about is the promise that Bluetooth on your computer would automatically recognise your phone as it came into range and sync with it without any further input required by the user as just one example. All of this would be seamless to the user whether it was his work computer or home computer and all syncs would be bi directional constantly updating all the fields chosen for syncing in the devcies in both directions. I'm not saying this can't be done but not without user intervention nad ina lot of cases luck.
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Ubuntu "Gutsy" + Evolution + Multisync + low-end SE Walkman phone here. Auto-sync over Bluetooth works well enough.
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| 09-01-2008 02:59 AM |
| Dogmann |
@martinharnevie
What i am talking about is the promise that Bluetooth on your computer would automatically recognise your phone as it came into range and sync with it without any further input required by the user as just one example. All of this would be seamless to the user whether it was his work computer or home computer and all syncs would be bi directional constantly updating all the fields chosen for syncing in the devcies in both directions. I'm not saying this can't be done but not without user intervention nad ina lot of cases luck.
Also the fact that even now ten years on there is plenty of bluetooth devcies that just will not talk to each other at all Hands free car kits are the prime example some phones will work with them whilst others won't. Which is pretty strange for what is meant to be one open standard where any devcie with the correct profile and permissions should have no difficulty in communication.
Or are you going to tell me all of the above is incorrect and Bluetooth is perfect? This is why i claim Bluetooth has failed to deliver on it's promise and don't even get me started on A2DP and it's problems. To be honest the only thing i ever use Bluetooth for is a headset whilst driveing and that's it otherwise IMO it's just not worth it. I admit it's come along way from the first Ericsson bluetooth headset i saw and used at the Mobile Data show in Earls court but even that was then delayed a further 6 months before they got it working properly.
Marc
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| 08-01-2008 10:33 PM |
| martinharnevie |
Some clarifications and comments here:
1. It's the Bluetooth Special Interest Group (SIG) which has its 10 years anniversary. Not the BT technology.
2. Those that say BT is overhyped must be blind as bats. The usage and growth speaks for itself. BT in gaming consoles, alone, is a 100 million units per annum business.
3. If some vendors implement poor BT stacks/drivers, BT per se should hardly be blamed for it. The same goes for poorly designed hardware. A large number of "BT devices" in the market place, espcially low cost BT units from China etc, are actually not BT certified while still, illegally, carrying the BT logo. Same things, even worse, happens with WiFi.
4. 95% of the problems people face with BT printing is related to Windows XP's extremely poor handing of buffers. Not with BT.
5. To Dogmann, kindly quote your reference to BT's "original claims". I think what you are referring to are certain product manufacturers' claims. Not Bluetooth SIG's claims. BT is a technology standard. Like with all such standards there are good and bad products. Same with WiFi. Same with GSM. Same with various cable standards, like Ethernet.
6. Since I'm partially in the Bluetooth business, i can just list a number of areas where Bluetooth is being used in large scale today:
- Machine control in factories
- Acquisition of data from medical instruments
- Data links for content updates to large information displays
- Rapid diagnosis of vehicles, e.g. AA alone in the UK have such BT devices installed in 3600 of their road assistance vehicles.
- Data uploads and refresh of large fleets of PDAs, e.g. police
- Long range datacommunication for integration of mobile livestock equipment over large farms, e.g. feeding stations, race machines, gates
- Data comms between computer and handheld barcode/rfid scanners for retail.
- Remote meter reading, e.g. electricity
- Gaming consoles
In terms of number of BT chips sold, the mobile phone and headset market still dominates, but even this little list is enough to demonstrate that those alleging that BT is not ubiquitous/pervasive do not know what they're talking about.
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| 08-01-2008 07:07 PM |
| Dogmann |
Hi all,
Well as someone that clearly remembers all the wonderful things Bluetooth was going to bring with seamless syncing as you came into range of your other devcies. I am for one feel Bluetooth has failed to deliver and for something that is meant to be one open standard it is quite incredible that there is so much incompatibility still with our devcies. Personally i also think A2DP has a long way to go before it can really replace wired solutions as well IMO. Here's hoping the next ten years sees Bluetooth actually deliver on what after was it's original claims.
Marc
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| 08-01-2008 04:06 PM |
| Unregistered |
10 years huh?
How about improving that goddam awful bluetooth stack software for PC's?
I have lost count of the amount of times I have loaded Bluetooth software and never got it to work
My Bluetooth home, My Bluetooth places, Bluetooth com ports, do you want to assign a port?
WTF is that all about?
You need a degree in understanding b0lax to use one.
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| 08-01-2008 03:03 PM |
| Unregistered |
Overhyped?
I remember when Bluetooth was launched and it was going to be the solution to so many connectivity problems. Bluetooth would be ubiquitous and many non-computing devices would use it. Well, it hasn't quite worked out that way! Just about the only area of consumer technology that does find Bluetooth being used is mobile phones. I can't really think of anywhere else is has been used successfully. It's fine for what it is - a modern upgrade for I/R - but it hasn't really had much of an impact.
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| 08-01-2008 01:11 PM |
| Unregistered |
bluetooth
Ahhh, well Steve that's not quite true what you are saying about audio. I do remember a videoclip where you showed of your A2DP bluetooth gateway from Nokia!
Bluetooth was definitely a step up from the old IR connections. Try sending data on the metro to someone via IR! I think the best bluetooth brought was the multi-pair able wireless headset. One headset to connect for calling to the home pc, the mobile phone, the work pc and trough A2DP the stereo. Will wireless HDMI do this for my glasses?
cheers, snoyt
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| 08-01-2008 12:33 PM |
| krisse |
zippiracer, I think that's true of all secure systems, none of them are actually 100% secure.
The question isn't whether something can be cracked, but how difficult it is, and whether anyone would conceivably bother.
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| 08-01-2008 11:54 AM |
| slitchfield |
Only from a few very old phones with very old firmware. You try that with a modern device 8-)
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| 08-01-2008 11:43 AM |
| zippiracer |
i think confidential data can be obtained, anonymously, and without the owner's knowledge or consent, from some bluetooth enabled mobile phones
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| 08-01-2008 11:00 AM |
| Unregistered |
blackgold
Yes it's very useful except that I am finding it very hard to get a printer with bluetooth let alone one that accepts formatting from nokia. Ask a retailer and they think bluetoot is only for phones. Anybody got any ideas on this?
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