BA7500G, SB live, digital audio a summary

BiKESEAT · 24th August 2001, 4:58 PM

Ok there seems to be a lot of people asking can i use this card, can i use that card with the GW BA7500G. It also seems in the large threads alot of people are talking but no one is listening.

I have looked around for the past few months at issues surrounding the SB Live and digital audio, and feel i can offer a summary and some answers.

The SB Live value uses a 3.5mm mini jack to output a coax digital signal. This consists of two digital signals - one for the front speakers, one for the rear. This is why on gateway systems which use and SB live this will work fine, simply plug the supplied 3.5mm mini cable with the bostons into the live and you're away.

The digial in on the speakers (i looked at the BA7500G's today) appears to be a similar situation - a 3.5mm stereo jack into the back of the unit. This would suggest how the speakers can then have front and rear in 3d games etc.

For dolby digital and AC3, i the signal is passed on the front channel, and nothing on the rear. I would assume that the speakers will detect this and decode the signal accordingly.

Using a mono 3.5mm jack plugged into the back of your live with just give you the AC3 signal if you want to use a commercial dolby decoder etc.

If you only have one digital output on your sound card, you WONT have rear sound. You may be able to bridge the coax out together, but then you will be getting the same signal front and rear. This also may stuff the sound card - does anyone know what happens if you double the load on a digital coax signal?

I hope that can provide a summary of the situation... a lot of helpful information is here:

http://alive.singnet.com.sg/

Specifically on the digital out:

http://alive.singnet.com.sg/tech/digital-io.htm

The speakers are also here (this link has been posted before)

http://www.bostonacoustics.com/gateway/

As a final point digital audio requires 1 ground and 1 singal line to give stereo sound (or in the case of AC3 6 channel sound). It is not like stereo requiring a separate line for each signal. This is why a seemingly single digital out on the SB live (which is infact a front and rear digital out) will provide sound for the fronts and the rears.

According to people in other threads, the digital input on the speakers IS 3.5mm, now can someone confirm if it is using a stereo cable?

One last point: although the BA7500's require a COAX digital input, this simply relates to the standard of the signal. Digital signals are either COAX (signal is sent through a wire, with a grounding sheath around it) or optical (signal is sent through optic fibre) Just because the input is described as COAX it does not necessarily mean it is transferred using an RCA cable as for digital input/output for dvd players etc.

In the case of the BA7500's, the digital signal is sent from the SB Live using a 3.5mm stereo jack. It is inputted to the speakers through a (reportedly) 3.5mm stereo jack. The standard for the signal is COAX - one wire for transmission and one for ground.

StOo_Burger · 24th August 2001, 5:07 PM

thankz heapz for the info man... it helpz a lot.. but, i am findin wut u have said a little contradicting...

The digital in on the speakers (i looked at the BA7500G's today) appears to be a similar situation - a 2.5mm stereo jack into the back of the unit. This would suggest how the speakers can then have front and rear in 3d games etc.

the above would suggest that we can use sblive values... however...

If you only have one digital output on your sound card, you WONT have rear sound. You may be able to bridge the coax out together, but then you will be getting the same signal front and rear. This also may stuff the sound card - does anyone know what happens if you double the load on a digital coax signal?

states on the first line that we can't... plz help?

also... my sblive seems to have 2 outputs... the green plug has a 1 next to it, and the black one beside it has a 2 next to it... is that correct?

edit: i know that the digital out is the yellow plug... n that this is the plug that we should use... i was just wondering...

BiKESEAT · 24th August 2001, 5:20 PM

What i was meaning if you make a cable that takes the coax output, and puts the same signal on to both the jacks on a 3.5mm plug, you will get sound from the front and the rear of the speakers. However it will be a copy of the front speakers at the rear.

The SBLive have two digital outs in that 3.5mm plug...

BiKESEAT · 24th August 2001, 5:30 PM

One other thing to note, there are 2 varieties of SB Live values, relating to different revisions over the past few years.

A summary is here:

http://alive.singnet.com.sg/features/products/

If you have one of the later value cards with the 3.5mm digital out you will be fine with the BA7500G's

If you have the earlier model value without the digital out, it is very easy to make one. However this will be for the front channel only, so you may have to bridge the signal to get sound from the rear speakers as well in normal applications. As i understand it if the signal from the front channels is a AC3 / dolby pro logic (ie movies), the unit will detect this and then you wil have rear sound. However for EAX, A3D and general wave output i don't think you will have any sound at the rear's.

Can someone who has received their speakers confirm this?

Infiltrator · 24th August 2001, 6:27 PM

As i posted in the for sale section

got my old order of the ba 735s.....pretty impressive stuff....hopefully it means good things for when i recieve the 7500's.

As with the 735s that I got the only connector that goes into the soundcard is this here: a 3.5mm mono plug

that connects to the "yellow digital out" on the sb live value.....I couldnt get sound to come out of em and it almost drove me nuts until i realised i had to enable digital audio in the volume control under advanced preferences.

Im guessing the 7500's will just have a stero version instead of mono plug to accomodate 4 speakers instead of 2.

Damn hypersnap....licence keeps crapping out on me

BiKESEAT · 24th August 2001, 6:31 PM

As the BA735's are only 2.1, that confirms that if you use a 3.5mm mono plug in the digital out of the SB live you will get the front channel. So in order for the BA7500's to work they MUST use a stereo plug.

StOo_Burger · 24th August 2001, 7:29 PM

Quote:

Originally posted by BiKESEAT
As the BA735's are only 2.1, that confirms that if you use a 2.5mm mono plug in the digital out of the SB live you will get the front channel. So in order for the BA7500's to work they MUST use a stereo plug.

umm... so... ??

sorry, but i don't get what u mean by stereo... will it just have the same plug/connector?

do u just plug it into the digital out n pray that it works? i ordered 2 sets of ba7500G's... n i have 2 systems with the sblive values...

alchemy · 24th August 2001, 7:44 PM

is anyone able to confirm that sblives are the only cards it will work with..

will any other card that has a spdif output be fine? for instance: the onboard c-media sound on the a7v266 has a spdif output - would that be fine?

RaD · 24th August 2001, 8:30 PM

are we getting two or four satelites for the $99 deal?

http://www.gateway.com.au/edm-images...a-aug-news.htm

RaD

max223 · 24th August 2001, 8:41 PM

Quote:

Originally posted by RaD
are we getting two or four satelites for the $99 deal?

http://www.gateway.com.au/edm-images...a-aug-news.htm

RaD

If you placed your older on a $99 BA7500G, you will get the 4.1
$89 is the 2.1 without the rear speakers.

The BA7500G package consists of one 2.1 box and a pair of rear speakers. Apparently Gateway is running out the rear speakers, so selling the 2.1 instead.

EDIT: Since Gateway sold out the rear speakers this morning, they dropped the price to $89 on that page without changing the image (4.1) and updated the image (2.1) this evening. That leaded to a lot of confusions as people thought you could still get the 4.1 version for $89.

FuK[NuTz]2k · 24th August 2001, 8:42 PM

For those that have sblives and want digital out

http://www.atomicmpc.com.au/forum.asp?cat=te&top=10703

yes i occasionally visit the site, and dont ask me i havent tried it i dont own a sblive

BiKESEAT · 24th August 2001, 10:07 PM

Any card that has digital out will give you sound, but only out of the FRONT speakers.

To make the rear speakers work you either need:

1) A Dolby AC3 or Prologic encoded signal

2) Bridge the single digital out to BOTH in digital channels in the speakers. However this will send the same information to the front and rear speakers - this will not give independant channels for A3D / EAX games.

3) A sounblaster live with digital out for BOTH front and rear channels.

An old SB live with a hacked digital out will be the same as situation 2), unless someone figures out a way to take the digital output for the REAR speakers as well. In which case if you make your own cable to go from the two RCA plugs which carry the digital signals to the 3.5mm stereo jack used by the BA7500's you're away =).

BiKESEAT · 24th August 2001, 10:21 PM

Quote:

Originally posted by StOoPyD

umm... so... ??

sorry, but i don't get what u mean by stereo... will it just have the same plug/connector?

do u just plug it into the digital out n pray that it works? i ordered 2 sets of ba7500G's... n i have 2 systems with the sblive values...

Ok... what i mean by stereo is that the cable that carries the digital signals (front and rear channels) requires three wires: a ground, the front signal, and the rear signal. The BA735's are 2.1, therefor having no rear speakers. The rear digital out on the SBlive isn't needed - so a mono (ground + digital signal) cable is supplied. The BA7500's need two digital signals as well as the ground, and hence use a "stereo" plug.

If you have SBLives with the 3.5mm digital out stop worrying, you will have no problems.

BiKESEAT · 24th August 2001, 10:47 PM

If you do wish to use a digital out from another sound card you will need to do the following:

If you have a COAX output in the form of a RCA plug, make an cable that goes from a single RCA plug to a 3.5mm stereo plug.

Connect the outside of the RCA plug (ground) to the ground of the stereo plug, and the signal to both of the signal tabs on the stereo plug. This will give the same signal to the front and rear speakers.

HOWEVER: I donnot know if this will place undue stress on the soundcard, as the signal for both the front and rear speakers is being drawn through the same output. Hence more current = maybe bad things. I don't know if this will break your sound card, and if you want to try it good, tell us how it went. When i recieve my speakers this is what i will be trying to make them work. If something breaks, i take no responsibility.

If you only want the front channels working for normal music etc, simply attach the signal wire from the RCA plug to the appropriate signal lug on the stereo plug. To find the right one,

1) Take the cable supplied by Gatewayand locate the end that goes into the SB live.

2) Take the outermost contact on the stereo plug, and find out which contact on the speaker end of the plug this is connected to. (use a multimeter, or even a battery and a light bulb).

Now you just have to solder your signal line from the RCA plug to the lug corrosponding to the contact previously found.

This method should give you working front speakers for music and games, and rears for AC3 or dobly prologic encoded signals.

If you have optical digital out, you can get a converter from jaycar for around $40 to convert to coax. Then do the above. See:

http://filemaker.webfactory.com.au/D...2589550&-find=

for converter.

Please note that i don't (yet) have these speakers, i am simply going on what i have read and what seems logical. I am 99% sure all of this is correct, but if someone has found otherwise please tell us!

BiKESEAT · 24th August 2001, 11:03 PM

Just another thing:

If you have an old SB live WITHOUT any form of digital out, it is very easy to make one, all you need is a small pin connector (think keylock / pwr rst / pwr switch etc connectors on your mobo) and a RCA plug. It just plugs right into the back of the card at the appropriate pins. See:

http://atlas.hemmet.chalmers.se/live...page.php?id=21

Now if someone can figure out if it is possible to do the same for the REAR channels output, anyone with an old sb live will be right to get 4.1 happening with the BA7500G's.

24th August 2001, 4:58 PM	#1
BiKESEAT Member Join Date: Jun 2001 Location: Brisbane, Australia Posts: 284	BA7500G, SB live and digital audio, a summary Ok there seems to be a lot of people asking can i use this card, can i use that card with the GW BA7500G. It also seems in the large threads alot of people are talking but no one is listening. I have looked around for the past few months at issues surrounding the SB Live and digital audio, and feel i can offer a summary and some answers. The SB Live value uses a 3.5mm mini jack to output a coax digital signal. This consists of two digital signals - one for the front speakers, one for the rear. This is why on gateway systems which use and SB live this will work fine, simply plug the supplied 3.5mm mini cable with the bostons into the live and you're away. The digial in on the speakers (i looked at the BA7500G's today) appears to be a similar situation - a 3.5mm stereo jack into the back of the unit. This would suggest how the speakers can then have front and rear in 3d games etc. For dolby digital and AC3, i the signal is passed on the front channel, and nothing on the rear. I would assume that the speakers will detect this and decode the signal accordingly. Using a mono 3.5mm jack plugged into the back of your live with just give you the AC3 signal if you want to use a commercial dolby decoder etc. If you only have one digital output on your sound card, you WONT have rear sound. You may be able to bridge the coax out together, but then you will be getting the same signal front and rear. This also may stuff the sound card - does anyone know what happens if you double the load on a digital coax signal? I hope that can provide a summary of the situation... a lot of helpful information is here: http://alive.singnet.com.sg/ Specifically on the digital out: http://alive.singnet.com.sg/tech/digital-io.htm The speakers are also here (this link has been posted before) http://www.bostonacoustics.com/gateway/ As a final point digital audio requires 1 ground and 1 singal line to give stereo sound (or in the case of AC3 6 channel sound). It is not like stereo requiring a separate line for each signal. This is why a seemingly single digital out on the SB live (which is infact a front and rear digital out) will provide sound for the fronts and the rears. According to people in other threads, the digital input on the speakers IS 3.5mm, now can someone confirm if it is using a stereo cable? One last point: although the BA7500's require a COAX digital input, this simply relates to the standard of the signal. Digital signals are either COAX (signal is sent through a wire, with a grounding sheath around it) or optical (signal is sent through optic fibre) Just because the input is described as COAX it does not necessarily mean it is transferred using an RCA cable as for digital input/output for dvd players etc. In the case of the BA7500's, the digital signal is sent from the SB Live using a 3.5mm stereo jack. It is inputted to the speakers through a (reportedly) 3.5mm stereo jack. The standard for the signal is COAX - one wire for transmission and one for ground. Last edited by BiKESEAT; 25th August 2001 at 10:33 AM.

24th August 2001, 5:07 PM	#2
StOo_Burger Ex-Admin Join Date: Jun 2001 Location: Brisbane, QLD Posts: 1,940	Re: BA7500G, SB live, digital audio a summary thankz heapz for the info man... it helpz a lot.. but, i am findin wut u have said a little contradicting... The digital in on the speakers (i looked at the BA7500G's today) appears to be a similar situation - a 2.5mm stereo jack into the back of the unit. This would suggest how the speakers can then have front and rear in 3d games etc. the above would suggest that we can use sblive values... however... If you only have one digital output on your sound card, you WONT have rear sound. You may be able to bridge the coax out together, but then you will be getting the same signal front and rear. This also may stuff the sound card - does anyone know what happens if you double the load on a digital coax signal? states on the first line that we can't... plz help? also... my sblive seems to have 2 outputs... the green plug has a 1 next to it, and the black one beside it has a 2 next to it... is that correct? edit: i know that the digital out is the yellow plug... n that this is the plug that we should use... i was just wondering... __________________ ¤ Computer Repairs Brisbane ¤ \| ¤ QuarkIT ¤ \| ¤ ellybean\|designs ¤ ¤ Supporting small business ¤

24th August 2001, 5:20 PM	#3
BiKESEAT Member Join Date: Jun 2001 Location: Brisbane, Australia Posts: 284	What i was meaning if you make a cable that takes the coax output, and puts the same signal on to both the jacks on a 3.5mm plug, you will get sound from the front and the rear of the speakers. However it will be a copy of the front speakers at the rear. The SBLive have two digital outs in that 3.5mm plug... Last edited by BiKESEAT; 25th August 2001 at 10:34 AM.

24th August 2001, 5:30 PM	#4
BiKESEAT Member Join Date: Jun 2001 Location: Brisbane, Australia Posts: 284	One other thing to note, there are 2 varieties of SB Live values, relating to different revisions over the past few years. A summary is here: http://alive.singnet.com.sg/features/products/ If you have one of the later value cards with the 3.5mm digital out you will be fine with the BA7500G's If you have the earlier model value without the digital out, it is very easy to make one. However this will be for the front channel only, so you may have to bridge the signal to get sound from the rear speakers as well in normal applications. As i understand it if the signal from the front channels is a AC3 / dolby pro logic (ie movies), the unit will detect this and then you wil have rear sound. However for EAX, A3D and general wave output i don't think you will have any sound at the rear's. Can someone who has received their speakers confirm this? Last edited by BiKESEAT; 3rd September 2001 at 8:46 PM.

24th August 2001, 6:27 PM	#5
Infiltrator Member Join Date: Jun 2001 Location: Sydney Posts: 213	As i posted in the for sale section got my old order of the ba 735s.....pretty impressive stuff....hopefully it means good things for when i recieve the 7500's. As with the 735s that I got the only connector that goes into the soundcard is this here: a 3.5mm mono plug that connects to the "yellow digital out" on the sb live value.....I couldnt get sound to come out of em and it almost drove me nuts until i realised i had to enable digital audio in the volume control under advanced preferences. Im guessing the 7500's will just have a stero version instead of mono plug to accomodate 4 speakers instead of 2. Damn hypersnap....licence keeps crapping out on me __________________ Folding@Home 80000 Points Milestone

24th August 2001, 6:31 PM	#6
BiKESEAT Member Join Date: Jun 2001 Location: Brisbane, Australia Posts: 284	As the BA735's are only 2.1, that confirms that if you use a 3.5mm mono plug in the digital out of the SB live you will get the front channel. So in order for the BA7500's to work they MUST use a stereo plug. Last edited by BiKESEAT; 25th August 2001 at 10:34 AM.

24th August 2001, 7:44 PM	#8
alchemy Member Join Date: Jun 2001 Location: Brisbane Posts: 537	is anyone able to confirm that sblives are the only cards it will work with.. will any other card that has a spdif output be fine? for instance: the onboard c-media sound on the a7v266 has a spdif output - would that be fine?

24th August 2001, 8:30 PM	#9
RaD Admin OC&H / Games Join Date: Jun 2001 Location: Gold Coast Oz Posts: 2,722	are we getting two or four satelites for the $99 deal? http://www.gateway.com.au/edm-images...a-aug-news.htm RaD

24th August 2001, 8:42 PM	#11
FuK[NuTz]2k Member Join Date: Jun 2001 Location: Melbourne Posts: 1,202	For those that have sblives and want digital out http://www.atomicmpc.com.au/forum.asp?cat=te&top=10703 yes i occasionally visit the site, and dont ask me i havent tried it i dont own a sblive

24th August 2001, 10:07 PM	#12
BiKESEAT Member Join Date: Jun 2001 Location: Brisbane, Australia Posts: 284	Any card that has digital out will give you sound, but only out of the FRONT speakers. To make the rear speakers work you either need: 1) A Dolby AC3 or Prologic encoded signal 2) Bridge the single digital out to BOTH in digital channels in the speakers. However this will send the same information to the front and rear speakers - this will not give independant channels for A3D / EAX games. 3) A sounblaster live with digital out for BOTH front and rear channels. An old SB live with a hacked digital out will be the same as situation 2), unless someone figures out a way to take the digital output for the REAR speakers as well. In which case if you make your own cable to go from the two RCA plugs which carry the digital signals to the 3.5mm stereo jack used by the BA7500's you're away =).

24th August 2001, 10:47 PM	#14
BiKESEAT Member Join Date: Jun 2001 Location: Brisbane, Australia Posts: 284	If you do wish to use a digital out from another sound card you will need to do the following: If you have a COAX output in the form of a RCA plug, make an cable that goes from a single RCA plug to a 3.5mm stereo plug. Connect the outside of the RCA plug (ground) to the ground of the stereo plug, and the signal to both of the signal tabs on the stereo plug. This will give the same signal to the front and rear speakers. HOWEVER: I donnot know if this will place undue stress on the soundcard, as the signal for both the front and rear speakers is being drawn through the same output. Hence more current = maybe bad things. I don't know if this will break your sound card, and if you want to try it good, tell us how it went. When i recieve my speakers this is what i will be trying to make them work. If something breaks, i take no responsibility. If you only want the front channels working for normal music etc, simply attach the signal wire from the RCA plug to the appropriate signal lug on the stereo plug. To find the right one, 1) Take the cable supplied by Gatewayand locate the end that goes into the SB live. 2) Take the outermost contact on the stereo plug, and find out which contact on the speaker end of the plug this is connected to. (use a multimeter, or even a battery and a light bulb). Now you just have to solder your signal line from the RCA plug to the lug corrosponding to the contact previously found. This method should give you working front speakers for music and games, and rears for AC3 or dobly prologic encoded signals. If you have optical digital out, you can get a converter from jaycar for around $40 to convert to coax. Then do the above. See: http://filemaker.webfactory.com.au/D...2589550&-find= for converter. Please note that i don't (yet) have these speakers, i am simply going on what i have read and what seems logical. I am 99% sure all of this is correct, but if someone has found otherwise please tell us! Last edited by BiKESEAT; 25th August 2001 at 10:35 AM.

24th August 2001, 11:03 PM	#15
BiKESEAT Member Join Date: Jun 2001 Location: Brisbane, Australia Posts: 284	Just another thing: If you have an old SB live WITHOUT any form of digital out, it is very easy to make one, all you need is a small pin connector (think keylock / pwr rst / pwr switch etc connectors on your mobo) and a RCA plug. It just plugs right into the back of the card at the appropriate pins. See: http://atlas.hemmet.chalmers.se/live...page.php?id=21 Now if someone can figure out if it is possible to do the same for the REAR channels output, anyone with an old sb live will be right to get 4.1 happening with the BA7500G's.