Playing split tracks

You need something like a Y cable.

Taken off internet

Make sure that the plug coming out of the computer is 1/8" with a tip, a ring, and a sleeve. That end of the cable should look identical to the plug on iPod headphones. The opposite side of the cable will "Y" out into two cables. Both should look the same. Either "RCA" (the same connections as you have on the back of your DVD player for audio), XLR (the three prong connector) or 1/4" (which looks like a bigger version of the headphone plug).

VERY IMPORTANT: If your 1/8" plug is mono meaning it has a "tip, sleeve" only this will not work. You can tell if its "tip, ring, sleeve" = stereo by how many black bands are on the prong. Two bands means that it is "tip, ring, sleeve" or stereo and that's good. One band on the prong means that it is "tip, sleeve" or mono and that's bad.

ALSO VERY IMPORTANT: If your "Y" cable goes from the 1/8" to two 1/4" connectors there are many ways this can be wired inside the cable and only some of the wiring schemes will work. Ideally you want sleeve on the 1/8" to go to sleeve on both 1/4" connectors. You want tip on the 1/8" connector to go to tip on ONE 1/4" connector and you want ring on the 1/8" connector to go to __TIP__ on the other 1/4" connector.

If your "Y" cable goes from 1/8" to two XLR connectors ideally you want sleeve on the 1/8" to go to pin-3 on both XLR connectors. You want tip on the 1/8" connector to go to pin-2 on one XLR connector and you want ring on the 1/8" connector to go to pin-2 on the other XLR connector.

Paul,

I am running a Y cable  1/8" to 1/4".  It is a tip, ring, sleeve end, as are my headphones.  If the outs are operating correctly I would think a split track recording would have vocal only in one earpiece (headphones) and background only in the other but it's not clean there either.  Any other suggestions?

Thanks,

.

What audio equipment are you connecting to?

Yamaha board, Bose amp & speakers.  Since I don;t hear the separate tracks on my headphones I'm inclined to believe that our sound system isn't the problem. Seems like an internal computer setting problem but I can't identify it.  

It's likely then that the laptop only sends stereo signals to the headphone socket. If you have an iPod then I believe they can handle split tracks. Otherwise you'd need to use a separate CD player with left and right outputs.

Maybe Jimco has some insight into this. He's the audio expert around here. He might know of some software that can do this?

I think the audio chip can only send a stereo signal to the headphone socket. Is this correct?

Well ...I would put it a little differently. The left channel is always mono and the right channel is always mono, so the audio chip can only send 2 mono signals to the headphone jack. As you said, mono music and mono voice (in this case). If these two mono tracks were sent to a mixing board then a stereo image could be created from them by using the pan controls.

I suggested using balance controls for the purpose of isolating the 2 mono channels from each other, in order to try to confirm that the tracks were recorded as cleanly as parsonjohn believes, and if they are to try to determine where the bleed is occurring in the signal path, at the headphone jack, before it or after it.

Got to go to bed now.

Hello Paul and Parsonjohn. I'm not sure I understand the problem correctly, but assuming I do then I would unplug adapters and play the track through the laptop speakers to double check the content.

[The following path assumes Vista or newer operating system -- there is a different path for XP. The Inspiron 1525's were shipped with Vista.]

Open the Playback tab of the Sound properties (right click on the audio icon on the taskbar and select Playback devices).

Set Speakers as the default playback device. While speakers are selected, click Properties on lower right.

On the Speaker Properties, select the Advanced tab (or Enhancements tab if there is one) and check "disable all enhancements". Something like image widening blends audio content from both channels and appears as bleeding.

Next select the Levels tab. I can't remember if Sigmatel had a balance control but that is where it would be. If there, play the track using the balance control to first listen to one channel then the other. (If no balance control then use a media player that has one. Older versions of Windows Media Player for example had one on the equalizer but newest one does not.)

While listening through the onboard speakers check for audio bleed. If present then double check the source material. The track itself might have captured bleeding during the mixdown or some such scenario. If no bleeding while listening through the speakers but still there through the headphone jack while using balance control then could be a fault in the jack.

Could also test the track on another computer, or burn it to a cd and play through a cd player, etc.

Basically, the user is using the laptop just as a CD player and outputting the signal thru the headphone socket via a Y cable to a yamaha mixing board and then thru an amp and speakers.

The split track CD is assumed configured Left channel = mono music and Right channel = mono voice

The balance control on the laptop speaker surely just controls the left and right speaker (stereo mix)

What we need is the left and right mono channels being outputted independently at the same time thru the headphone socket. Once the user has split the two signals to the Yamaha board they can then route the signals to wvichever external Bose speaker they wish. However, I think the audio chip can only send a stereo signal to the headphone socket. Is this correct?

Parsonjohn,

My brain was a little foggy last night and I was thinking that the track was a file in the computer, but you had explained that it is on a cd, so sorry if I caused any confusion there. Because it is on a cd I assume that you have tested it on a cd player or boombox to rule out any problem with the track itself.

You wrote: "If the outs are operating correctly I would think a split track recording would have vocal only in one earpiece (headphones) and background only in the other but it's not clean there either "

Assuming that the tracks are clean then you are exactly correct about that. The audio at the headphone jack should not have bleed through between channels. Bleed through would be caused either by a configuration problem or hardware. My suggestion to use the balance controls and to listen through the speakers was to try to see if the headphone jack is faulty. The "balance" control in Windows is not a real balance control. It consists of 2 volume controls, one for each channel, thus allowing for isolation of the channels from each other.

"Since I don;t hear the separate tracks on my headphones I'm inclined to believe that our sound system isn't the problem. Seems like an internal computer setting problem but I can't identify it. "

As far as configuration, disabling "all enhancements" is a start. The main way to correct configuration is to re-install the Sigmatel audio driver. When it is freshly installed it will be back to its default configuration settings. If that does not cure the problem then you could remove the Sigmatel driver from the system and let Windows install its own native audio driver (but only if you have Vista or newer -- can't do this in XP). The native driver is very basic with fewer bells & whistles to get mis-configured.

If you were to take those steps with the audio drivers and the situation remained the same, then I would rule out configuration as the cause of the bleeding and concentrate on hardware as the cause.

Hi Paul. If I understand correctly, when Parsonjohn plugs headphones directly into the jack he is hearing bleed through from one channel into the other. That is the problem -- nothing to do with adapters or anything in the signal path further down the line.

The headphone jack on your laptop is a Stereo Unbalanced output. The Y cable needs to be Stereo 1/8 TRS to 2 Mono 1/4 TRS. This plugs into the Balanced inputs of your mixer board.

If that's how you've already got it set up as, then I'd check the Y cable. Maybe get hold of another one and compare.

www.amazon.com/.../B0062QPERU

See, the Y adapter that you keep talking about already exists in the headphone plug. It sends the mono right channel to the right earpiece and the mono left channel to the left earpiece. Parsonjohn is correct in saying that he should only hear right channel content through the right channel and the left channel content through the left channel. If the content from one channel is coming through the other channel, that is wrong -- not supposed to happen.

Thank you all for the contributions to my issue.  So there are two headphone jacks and both have the bleed.  What are the chances that I can disassemble and correct this myself?

First you have to determine if the jacks are causing the problem. Do the tests i outlined last night -- listen through the onboard speakers and isolate one channel from the other to hear better. If you hear the bleed-through in the onboard speakers then I would not think that that the cause is the headphone jack(s).

On the Inspiron 1525 the jacks are part of the motherboard and not normally considered replaceable parts.

Parsonjohn, in your initial post you wrote that " the out jacks don't cleanly separate the tracks."  Paul thinks you meant the output jacks of the mixer but I assumed that you meant the output jacks of the laptop. Obviously this would make a huge difference in the way we have been looking at this issue, so please clarify if you don't mind.