Go Back   Team-BHP > Around the Corner > Shifting gears > Gadgets, Computers & Software


Reply
 
Thread Tools Search this Thread
Old 22nd October 2008, 12:54   #31
Team-BHP Support
 
tsk1979's Avatar
 
Join Date: Feb 2005
Location: New Delhi
Posts: 22,852
Thanked: 15,406 Times
Default

Wifi link can sustain 4-5Mbps easily. So it won't be bottleneck.
So what are the bottlenecks.
I doubt audio transmission even in Hi-Fi will cross 1Mbps. There will not be any loss in transmission, as the data which gets transmitted will be exactly similar to data which gets received.
However, at the sound card end, the ADC-DAC's will decide the quality. So a good sound card is a must, and take direct optical link from CD player(most sound cards do that).

Rest assured, I can confidently say. what whether you use Wifi or Gigabit LAN, there will be absolutely no difference in quality for audio
tsk1979 is offline   Reply With Quote
Old 22nd October 2008, 12:58   #32
Distinguished - BHPian
 
DerAlte's Avatar
 
Join Date: Mar 2007
Location: Bangalore
Posts: 8,076
Thanked: 2,867 Times
Default

In data transfer over IEEE802.11 b/g/n ("WiFi"), there is no data compression / decompression involved, not even at hardware level. The packets are carted over as is, and if one wants to achieve a higher data throughput rate, all such compression / decompression is done before giving it to the transport layer. Visualize it like this: WiFi is like the postal department; whether you send 12 normal print pages or take a 1-page printout with all 12 printed in it is left to you; Post only deals with the envelop.

The only locha that audio faces over WiFi and such protocols is the absence of any guarantees of byte (packet) sequence. This means buffering, and THAT can cause problems once in a while. People walking around is also an impedance to the waves, na. So all such disturbances can statistically cause problems in CODECed music and streaming once in a while. The main issue is in how many parts would one want to split the hair strand!

Telecom (multiple channels of voice communications between exchanges, for example) goes great lengths to achieve synchronous communications, even though the whole thing sounds like TCP/IP communications basically.
DerAlte is offline   Reply With Quote
Old 22nd October 2008, 13:17   #33
BHPian
 
sk456's Avatar
 
Join Date: Jun 2006
Location: @Noida/Gurgaon
Posts: 570
Thanked: 7 Times
Default

Interesting!! An eye opener for me! Never thought of it this technically. Now am itching to try it sometime ! Someone gift me a squeezebox !

But come to think of it -will it not get the cable guys out of business as it will soon make expensive interconnects redundant.

Last edited by sk456 : 22nd October 2008 at 13:31.
sk456 is offline   Reply With Quote
Old 22nd October 2008, 13:26   #34
Senior - BHPian
 
reignofchaos's Avatar
 
Join Date: Apr 2007
Location: Bangalore
Posts: 2,175
Thanked: 1,094 Times
Default

Quote:
Originally Posted by surfatwork View Post
Really? I presume you have tried all of these? I have, and I can say that they are perfectly adequate for streaming compressed audio files - which is what mp3/ogg/wma etc. are.
There is no perfectly adequate in high end audio - more is always better. I'd be curious what audio setup did you try this with? Also nowhere did anyone mention anything about lossy compressed audio. We are assuming bitperfect audio here.

A squeezebox can use ethernet if the need be. One is not limited to 802.11g. As with all data communication, this is 100% foolproof with error checking/correction at both ends.
reignofchaos is offline   Reply With Quote
Old 22nd October 2008, 13:29   #35
Senior - BHPian
 
Bass&Trouble's Avatar
 
Join Date: Mar 2006
Location: Bombay
Posts: 2,742
Thanked: 65 Times
Default

Thanks everyone! Now I'm even more confused than I was at the beginning.

Anyway, one new development is that, one Mac will be permanently stationed near the audio gear. So this will be hardwired to the audio setup. Now the job is to get another Mac sitting in another room to play audio through the music system. How can this be achieved "most losslessly"? And what sort of settings/ software am I looking at on both machines so that audio from the remote machine is transmitted to machine in equipment rack via wireless?

Is it possible to change/ add sound card to a Mac?
Bass&Trouble is offline   Reply With Quote
Old 22nd October 2008, 14:41   #36
Distinguished - BHPian
 
DerAlte's Avatar
 
Join Date: Mar 2007
Location: Bangalore
Posts: 8,076
Thanked: 2,867 Times
Default

Quote:
Originally Posted by Bass&Trouble View Post
... Now I'm even more confused than I was at the beginning.

Anyway, one new development is that, one Mac will be permanently stationed near the audio gear. ...
Kya B&T-bhai, you are being the epitome of humility, kya?

Mac near the audio gear sounds good, especially if you consider a Mac Mini (without monitor, kbd and mouse; configure once and then "anand nariyal peeley"). And perhaps you don't need to put an audio card, you could consider some audiophile DACs over USB.

Edit:
* There is another question associated with this: which Mac is the master, and which is the slave? Usually most "media players" (both hardware and software varieties) put the User Interface near the Audio equipment, i.e. you are pulling the media file from a storage location elsewhere, but essentially sitting near where the audio equipment / TV is and controlling the playback. Doing it from the storage location (your "another Mac sitting in another room") would mean you are "pushing" media to the 'slave' Mac, and playback control is from the 'master' Mac. This scenario is not the typical HTPC scenario, and you will need to search for the software bits and pieces to achieve that seamlessly
* How can this be achieved "most losslessly"? As losslessly as the encoding used in the media to be played back (Audio / Video / Photo). If you using the external DAC, only the decoded bytes will be sent to the DAC - there is no 'transmission related loss' over the wireless
* I trust you are OK with the video section of the 'slave' device; most of the discussion has been around audio here so far

Last edited by DerAlte : 22nd October 2008 at 15:09.
DerAlte is offline   Reply With Quote
Old 23rd October 2008, 00:02   #37
Team-BHP Support
 
navin's Avatar
 
Join Date: Mar 2004
Location: mumbai
Posts: 22,230
Thanked: 3,642 Times
Default

Quote:
Originally Posted by Bass&Trouble View Post
Thanks everyone! Now I'm even more confused than I was at the beginning.
Quote:
Originally Posted by DerAlte View Post
In data transfer over IEEE802.11 b/g/n ("WiFi"), there is no data compression / decompression involved, not even at hardware level.
Quote:
Originally Posted by tsk1979 View Post
Wifi link can sustain 4-5Mbps easily.
OK guys if we have succeeded in confusing B&T we really got to back up.

B&T think about it this way. Have you come across one (just one) Wi-Fi transmitter that can transmit audio without making it sound like it is FM? Airport? Senheisser RS140? Roku? Olive? W1 (Audioengine)? Sonus?
All are versions of this
Sonneteer template css+dhtml based (6moons had a good review)

Correct us if we are wrong we are assuming that you want to transmit hifi audio (not mid-fi) over wireless with the quality of wireline (Supra-Neutrik). Right?

Maybe this site can help.
Audio Currents - PC PowerLine Audio - news, reviews, and talk

Of all the plug and play devices available today I'd choose between the Bard and the Transporter (http://images.slimdevices.com/transp...orter-home.jpg) they might not replace good wire but that is the commerically available state of the art.

BTW why Mac? why not get a dedicated Music Server like Cambridge Audio's 640H? or if you want something exotic like this TEAC machine.
Esoteric D-03 Dual Mono DAC Available
navin is offline   Reply With Quote
Old 23rd October 2008, 10:04   #38
Team-BHP Support
 
Rehaan's Avatar
 
Join Date: Feb 2004
Location: Bombay
Posts: 22,229
Thanked: 21,888 Times
Default

Quote:
Originally Posted by greenhorn View Post
...navin and I had a bit of a discussion via PM, and both of us remain unconvinced. I think he feels that some sort of compression/distortion would be involved when Wi Fi is used , while i think it shouldn't make a difference. Anyone care to clarify ?
I guess certain streaming players might (lossy) compress/reencode the audio it is playing on the fly and thats what navin is referring to?
But in most cases I would agree with you greenhorn. Data is data and should end up being bit-to-bit exact when it comes out at the other end.

Quote:
Originally Posted by Bass&Trouble View Post
Thanks everyone! Now I'm even more confused than I was at the beginning.

Anyway, one new development is that, one Mac will be permanently stationed near the audio gear. So this will be hardwired to the audio setup. Now the job is to get another Mac sitting in another room to play audio through the music system. How can this be achieved "most losslessly"? And what sort of settings/ software am I looking at on both machines so that audio from the remote machine is transmitted to machine in equipment rack via wireless?

Is it possible to change/ add sound card to a Mac?
B&T,

The way i see it, your biggest enemy is not quality, but latency.

Any high bandwidth / "real-time" data going over wifi will probably need some kind of buffering in order to be on the safe side and prevent any breakup - caused by interference / neighbors cordless phone / police car driving by etc.

I guess devices like the airport or whatever that mac thing are have the advantage of being able to decode the compressed audio at the hardware end -- which means that they can buffer the MP3 instead of the raw audio, which means in a few seconds they have 30+ secconds in buffer already, and only have to rebuffer from 0seconds when you change the track suddenly. (This is my guess)

Devices like the WMB54g which are essentially WIFI soundcards dont have that luxury since they have to play anything you hear on the PC (and not just limited to mp3s etc from itunes).

IMO, the easiest way to avoid the whole buffering/latency - as mentioned, is to have all the media on your pc near the audio equipment, and then the only latency experiences will be the time it takes to transmit the "click" on the play button to the "media server" machine. (Also, tiny/negligible latency in browsing the music archives / searching etc. -- its basically like running remote administration on your home network.

B&T - could you tell us some more about this project. Will it be music only (what kind of colection does the person have - mp3s? CDs?)
Will it be videos as well? (dvds? bluray?)

cya
R

ps - everything above is my basic understanding and open to correction!

Last edited by Rehaan : 23rd October 2008 at 10:13.
Rehaan is offline   Reply With Quote
Old 23rd October 2008, 10:26   #39
Distinguished - BHPian
 
DerAlte's Avatar
 
Join Date: Mar 2007
Location: Bangalore
Posts: 8,076
Thanked: 2,867 Times
Default

Quote:
Originally Posted by Rehaan View Post
... police car driving by etc. ...
Rehaan baba, Mumbai mamoo vahans don't radiate, at least not in the 0.9-2.4GHz range!
DerAlte is offline   Reply With Quote
Old 23rd October 2008, 10:56   #40
Senior - BHPian
 
NetfreakBombay's Avatar
 
Join Date: Jan 2008
Location: Bombay
Posts: 1,375
Thanked: 315 Times
Default

Quote:
Originally Posted by Rehaan View Post
The way i see it, your biggest enemy is not quality, but latency.
Tried to measure latency on WiFi. I don't think it would matter that much.

Copied 2 GB videos from PC to Cell. And measured latency at that time. It was just 1 ms. Increased to 2 - 3 ms if I stood between PC and router.

Can I have the attention of computing audio gurus!-wifi-latency.png

However latency due to:

1. Playback on master PC + streaming to network
2. Transfer to slave PC
3. Playback on slave PC with some player

Would add latency of 100 ms I think. Which should not be significant.

BTW, wireless mic used in live performance... how do they work? FM or some digital encoding? Can you use something similar?

Last edited by NetfreakBombay : 23rd October 2008 at 10:58.
NetfreakBombay is offline   Reply With Quote
Old 23rd October 2008, 11:34   #41
Team-BHP Support
 
navin's Avatar
 
Join Date: Mar 2004
Location: mumbai
Posts: 22,230
Thanked: 3,642 Times
Default

Quote:
Originally Posted by Rehaan View Post
I guess certain streaming players might (lossy) compress/reencode the audio it is playing on the fly and thats what navin is referring to?
But in most cases I would agree with you greenhorn. Data is data and should end up being bit-to-bit exact when it comes out at the other end.
What about reflections and refractions of the RF signal between transmitter and reciever?

Quote:
Originally Posted by NetfreakBombay View Post
Would add latency of 100 ms I think. Which should not be significant.
BTW, wireless mic used in live performance... how do they work? FM or some digital encoding? Can you use something similar?
1. 100 ms is huge.
2. Wireless mics and headphones operate well but their fidelity is not adequate for B&T's application. If the fidelity B&T wanted was just that then there are a dozen solutions but B&T wants the fidelty to be nothing less than good quality RCA cable (think Nordost, Kimber, VdH, etc...) there is lies the problem.
navin is offline   Reply With Quote
Old 23rd October 2008, 11:58   #42
Senior - BHPian
 
reignofchaos's Avatar
 
Join Date: Apr 2007
Location: Bangalore
Posts: 2,175
Thanked: 1,094 Times
Default

Quote:
Originally Posted by Bass&Trouble View Post
Thanks everyone! Now I'm even more confused than I was at the beginning.

Anyway, one new development is that, one Mac will be permanently stationed near the audio gear. So this will be hardwired to the audio setup. Now the job is to get another Mac sitting in another room to play audio through the music system. How can this be achieved "most losslessly"? And what sort of settings/ software am I looking at on both machines so that audio from the remote machine is transmitted to machine in equipment rack via wireless?

Is it possible to change/ add sound card to a Mac?
This is exactly the same as my setup then. Get a sound card with good SPDIF output like ESI Juli@ or EMU 1212M, get a good quality external DAC (there are tonnes of them - choose anything that you deem fit). Enable file sharing on the music server and just play the music on that machine stationed beside the audio setup. This is foolproof and probably the best quality output thats possible.

@Navin: I hate both VdH and Nordost :-). VdH in the underground hifi scene is also known as bland'n dull. It seems to roll off the top end pretty rapidly and as a result is quite dark sounding and can cause boom in most setups. I did manage to audition two of Nordost's entry lvl interconnects - Red Dawn and Blue Heaven. Both were pretty pathetic - Poor resolution and a very very high noise floor pointing to the fact that those fancy flat cables don't have adequate shielding.

For low price, high value cables, I really like Audio Art.

Last edited by reignofchaos : 23rd October 2008 at 12:03.
reignofchaos is offline   Reply With Quote
Old 23rd October 2008, 12:04   #43
Team-BHP Support
 
navin's Avatar
 
Join Date: Mar 2004
Location: mumbai
Posts: 22,230
Thanked: 3,642 Times
Default

Quote:
Originally Posted by reignofchaos View Post
This is exactly the same as my setup then. Get a sound card with good SPDIF output like ESI Juli@ or EMU 1212M, get a good quality external DAC (there are tonnes of them - choose anything that you deem fit). Enable file sharing on the music server and just play the music on that machine stationed beside the audio setup. This is foolproof and probably the best quality output thats possible.
So what you are saying it that the files are transmitted wirelessly from one PC to the other but the decoding and digital to analog conversion happens locally. Now can a good sound card be stuffed into a Mac Mini? Any larger PC and WAF is gonna get affected.
navin is offline   Reply With Quote
Old 23rd October 2008, 13:03   #44
Senior - BHPian
 
reignofchaos's Avatar
 
Join Date: Apr 2007
Location: Bangalore
Posts: 2,175
Thanked: 1,094 Times
Default

Quote:
Originally Posted by navin View Post
So what you are saying it that the files are transmitted wirelessly from one PC to the other but the decoding and digital to analog conversion happens locally. Now can a good sound card be stuffed into a Mac Mini? Any larger PC and WAF is gonna get affected.
Yup thats exactly my point. You can't stuff anything into a mac mini. However you can use an external USB solution. Infact many dacs like the benchmark have a built in USB interface.
reignofchaos is offline   Reply With Quote
Old 24th October 2008, 10:36   #45
BHPian
 
Fillmore's Avatar
 
Join Date: Nov 2007
Location: Bangalore
Posts: 271
Thanked: 127 Times
Default Wireless streaming

I stream music in wireless mode from iTunes to my AVR.

Have stopped playing from CD's, transferred all the music to an external hdd, entire setup organized with iTunes.

Setup
- Apple Airport Express Base-station plugged in next to the amp
(model - 802.11n, this is the latest. its 5 times faster than the prev .g model, speed is 300mbps / )

- Stereo to RCA cable from Airport Express to the AVR
(quality is pretty good, absolutely no breaks in sound even when streaming wav's directly from the laptop CD drive)

- Airport Express configured to connect to my existing wireless n/w
(The default setup is for the unit to act as the router itself, but since my setup is such that the AVR not near the incoming broadband cable, I set it up to Join the existing Netgear wireless n/w)

- Once you setup this, iTunes has an option to Stream to Computer Or to external device.

Have posted a pic of the device, placed the Reynolds pen at the side so that you know the size of the streaming device.
Let me know if you have any questions regarding how to configure it.

ps: I do not have a Mac , I stream from XP.
Attached Thumbnails
Can I have the attention of computing audio gurus!-aexp.jpg  

Fillmore is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Car Audio Advice from the Audio Gurus: Use "Search thread" before posting a new Q! Sam Kapasi In-Car Entertainment 13526 16th August 2017 23:02
Gurus I am seeking serious attention sinhsha In-Car Entertainment 27 12th March 2008 11:22
A request to all the audio gurus .. Can this be repaired ?? mclaren1885 In-Car Entertainment 38 13th July 2006 13:21


All times are GMT +5.5. The time now is 09:45.

Copyright 2000 - 2017, Team-BHP.com
Proudly powered by E2E Networks