Headphone out to the S1 Pro XLR-In

[prakashwadhwani]

Hi ... I'm running short of outputs from my Mixer.

I'm aware I can feed the S1 Pro's (first 2 channels XLR-In) either a Line/Stereo Out from my Mixer or even the Aux-Out.

However, can I use the Headphones socket to feed an output to the S1 Pro Channels?

Of course I'd use either a headphones stereo out to a single (summed/mono) XLR-in ... either Channel 1 or 2 on the S1 Pro
... or ...
or a headphones stereo out to dual XLR-ins ie Channels 1 and 2 on the S1 Pro

Would both work? If not ... why? 

Pls check the attached Analogue Output specs of my Mixer's Data Sheet  attached ... and links of the proposed cables.

Link1 - https://www.amazon.in/Cable-Ma...WJ2GNC3G74JX0VB95WD2

This cable converts a Stereo Signal to a Mono one ... so should work


Link2 - https://www.amazon.in/Cable-Ma...RA8FDBNX0B47NJB3R4AJ

This cable doesn't specify if it converts a Stereo Signal to a Mono one ... so I'm unsure if it will work. I would prefer to use THIS CABLE as it's a 1/4" jack and will fit my Mixer's Headphone socket AS-IS, without any converter.

I hope I've been able to get myself across clearly ... 

[Dave_Hazel]

You can use the headphones output to provide a line level feed to a power amplifier but it will be unbalanced.

Given that outputs are low impedance and inputs are high impedance you should be able to drive more than one input with a parallel feed from one output.

Cheapest way is to use a 6.35 stereo Jack Y splitter such as...

https://www.google.com/aclk?sa...QQ9aACCGY&adurl=

If you do decide to use the headphones output be careful that you do not end up feeding a balanced input with a stereo feed, it might 'seem' to work but you will get strange results.  

[ST - Pro]

Hi Prakash Wadhwani,

Welcome to the Bose Portable PA Community.

Prakash Wadhwani posted:

Hi ... I'm running short of outputs from my Mixer.

I'm aware I can feed the S1 Pro's (first 2 channels XLR-In) either a Line/Stereo Out from my Mixer or even the Aux-Out.

However, can I use the Headphones socket to feed an output to the S1 Pro Channels?

Yes. The simplest thing that could work is to connect the mixer headphone output to the S1 Pro Aux input. This should be fine for cable lengths up to 20 feet (6 meters).  The result will be mono.

click the picture above for more details.

You can then daisy chain the mono signal from the first S1 Pro to a second S1 Pro.

For details see: S1 Pro Daisy Chain Settings

Of course I'd use either a headphones stereo out to a single (summed/mono) XLR-in ... either Channel 1 or 2 on the S1 Pro

A simple cable adapter like you have described is shorting the left and right outputs together.  Please see: Stereo to Mono Conversion to find out why this is not recommended.

... or ...
or a headphones stereo out to dual XLR-ins ie Channels 1 and 2 on the S1 Pro

This could work, but takes two channels on the S1 Pro. Also, the conversion provides two unbalanced connections. This should be fine for cable lengths up to 20 feet (6 meters).

Would both work? If not ... why? 

Pls check the attached Analogue Output specs of my Mixer's Data Sheet  attached ... and links of the proposed cables.

Link1 - https://www.amazon.in/Cable-Ma...WJ2GNC3G74JX0VB95WD2

This cable converts a Stereo Signal to a Mono one ... so should work


Link2 - https://www.amazon.in/Cable-Ma...RA8FDBNX0B47NJB3R4AJ

This cable doesn't specify if it converts a Stereo Signal to a Mono one ... so I'm unsure if it will work. I would prefer to use THIS CABLE as it's a 1/4" jack and will fit my Mixer's Headphone socket AS-IS, without any converter.

I hope I've been able to get myself across clearly ... 

A cable like this should work.

Click picture for more details.

If you want to run the S1 Pro systems in stereo, you could use a cable like this.

Click picture for more details.

I have used a cable like the one immediately above. I was able to pull the two 1/4" ends apart so I could the 1/4" ends to separate S1 Pro systems. 

Does that help?
ST

[prakashwadhwani]

Dave Hazel posted:

You can use the headphones output to provide a line level feed to a power amplifier but it will be unbalanced.

Given that outputs are low impedance and inputs are high impedance you should be able to drive more than one input with a parallel feed from one output.

Cheapest way is to use a 6.35 stereo Jack Y splitter such as...

https://www.google.com/aclk?sa...QQ9aACCGY&adurl=

If you do decide to use the headphones output be careful that you do not end up feeding a balanced input with a stereo feed, it might 'seem' to work but you will get strange results.  

Thx so much for your reply ... Very informative! both ... the impedance part & particularly re not feeding a Stereo signal into a balanced input (an easy enough mistake to make for a rookie) given both connectors look similar with 2 lines (separators).

[prakashwadhwani]

ST posted:

Hi Prakash Wadhwani,

Welcome to the Bose Portable PA Community.

Prakash Wadhwani posted:

Hi ... I'm running short of outputs from my Mixer.

I'm aware I can feed the S1 Pro's (first 2 channels XLR-In) either a Line/Stereo Out from my Mixer or even the Aux-Out.

However, can I use the Headphones socket to feed an output to the S1 Pro Channels?

Yes. The simplest thing that could work is to connect the mixer headphone output to the S1 Pro Aux input. This should be fine for cable lengths up to 20 feet (6 meters).  The result will be mono.

click the picture above for more details.

You can then daisy chain the mono signal from the first S1 Pro to a second S1 Pro.

For details see: S1 Pro Daisy Chain Settings

Of course I'd use either a headphones stereo out to a single (summed/mono) XLR-in ... either Channel 1 or 2 on the S1 Pro

A simple cable adapter like you have described is shorting the left and right outputs together.  Please see: Stereo to Mono Conversion to find out why this is not recommended.

... or ...
or a headphones stereo out to dual XLR-ins ie Channels 1 and 2 on the S1 Pro

This could work, but takes two channels on the S1 Pro. Also, the conversion provides two unbalanced connections. This should be fine for cable lengths up to 20 feet (6 meters).

Would both work? If not ... why? 

Pls check the attached Analogue Output specs of my Mixer's Data Sheet  attached ... and links of the proposed cables.

Link1 - https://www.amazon.in/Cable-Ma...WJ2GNC3G74JX0VB95WD2

This cable converts a Stereo Signal to a Mono one ... so should work


Link2 - https://www.amazon.in/Cable-Ma...RA8FDBNX0B47NJB3R4AJ

This cable doesn't specify if it converts a Stereo Signal to a Mono one ... so I'm unsure if it will work. I would prefer to use THIS CABLE as it's a 1/4" jack and will fit my Mixer's Headphone socket AS-IS, without any converter.

I hope I've been able to get myself across clearly ... 

A cable like this should work.

Click picture for more details.

If you want to run the S1 Pro systems in stereo, you could use a cable like this.

Click picture for more details.

I have used a cable like the one immediately above. I was able to pull the two 1/4" ends apart so I could the 1/4" ends to separate S1 Pro systems. 

Does that help?
ST

Thanks a ton for your reply. You've taken the time & effort to break down every aspect of my query & address it lucidly even with illustrations. Much obliged

[Dave_Hazel]

Prakash Wadhwani posted

Thx so much for your reply ... Very informative! both ... the impedance part & particularly re not feeding a Stereo signal into a balanced input (an easy enough mistake to make for a rookie) given both connectors look similar with 2 lines (separators).

Keep in mind also that a balanced cable and a stereo cable are very different. There are plenty of Internet sellers out there who do not know or realise there is a difference. In fact I've had some of them try to tell me they are the same!

To a point they are the same inasmuch that the connections are the same but the cable is constructed differently...

A stereo cable must be two separate signal conductors that are individually screened. Whereas a balanced cable is a 'twisted pair' of signal conductors in an overall screen.

If you use a balanced cable on a stereo signal it will induce cross-talk between channels. If you use a stereo cable on a balanced signal it will degrade the balanced lines noise rejection properties. 

[prakashwadhwani]

https://www.cablematters.com/p...le-male-to-male.aspx

1) Could the above cable be used to feed a backing track from my phone into the S1 Pro XLR ??  The cable manufacturer clearly states the stereo signal is being summed into a mono signal and is for this purpose and yet you're not recommending it for the reason below. Is the manufacturer wrong in their description & recommendation? (s you've pointed out, I understand the S1 Pro Aux-In would be a better Stereo-to-Stereo Solution, but am just exploring other possibilities, so please bear with me).

You (ST) wrote:
A simple cable adapter like you have described is shorting the left and right outputs together.  Please see: Stereo to Mono Conversion to find out why this is not recommended.

S1 Pro system

Here is the rule: Outputs are low impedance and must only be connected to high impedance inputs -- never, never tie two outputs directly together -- never. If you do, then each output tries to drive the very low impedance of the other, forcing both outputs into current-limit and possible damage. As a minimum, severe signal loss results.

I did read the above but couldn't grasp the underlying principle properly. Would appreciate if you could break it down a bit for me.

2) Can I use the above cable 3.5mm jack, on a 6.35mm to 3.5mm converter and then from the headphones out of my Mixer into the S1 Pro? Will that perform identically?

3) If I want to position the S1 Pro some 20 metres away from my Mixer, what solution would you recommend I go with (I'm presuming something balanced here)?

[ST - Pro]

Hi Prakash Wadhwani,

Prakash Wadhwani posted:

https://www.cablematters.com/p...le-male-to-male.aspx

1) Could the above cable be used to feed a backing track from my phone into the S1 Pro XLR ??  The cable manufacturer clearly states the stereo signal is being summed into a mono signal and is for this purpose and yet you're not recommending it for the reason below. Is the manufacturer wrong in their description & recommendation? (s you've pointed out, I understand the S1 Pro Aux-In would be a better Stereo-to-Stereo Solution, but am just exploring other possibilities, so please bear with me).

You (ST) wrote:
A simple cable adapter like you have described is shorting the left and right outputs together.  Please see: Stereo to Mono Conversion to find out why this is not recommended.

S1 Pro system

Here is the rule: Outputs are low impedance and must only be connected to high impedance inputs -- never, never tie two outputs directly together -- never. If you do, then each output tries to drive the very low impedance of the other, forcing both outputs into current-limit and possible damage. As a minimum, severe signal loss results.

I did read the above but couldn't grasp the underlying principle properly. Would appreciate if you could break it down a bit for me.

Basically, there's a right way and a wrong way to do things. We cannot know from the link you provided, what the manufacturer has done.  Follow the link and read the section about Unbalanced Summing to find out more.

2) Can I use the above cable 3.5mm jack, on a 6.35mm to 3.5mm converter and then from the headphones out of my Mixer into the S1 Pro? Will that perform identically?

A cable like this should work.

Click picture for more details.

Or  a cable like this

https://www.amazon.in/3-5mm-CN...7CSS2ZGW/ref=sr_1_13

plus an adapter

https://www.amazon.in/Advent-B...072MK552T/ref=sr_1_1

3) If I want to position the S1 Pro some 20 metres away from my Mixer, what solution would you recommend I go with (I'm presuming something balanced here)?

For that distance you would want a balanced connection or consider going with a wireless solution.

You will need a dual DI box like this:

http://www.artproaudio.com/pro...nel-level-converter/

Unfortunately, you'd have to run two 20-meter cables to make this all work.

It would be much simpler if you can run another (mono) aux output from your mixer.

ST

[Dave_Hazel]

The point about a stereo signal is that the 2 signals are different. Think of it as two people walking along side-by-side holding hands. Provided they both walk at the same pace all is well. But if one goes faster than the other either the fast will drag the slower, or the slower will hold the faster one back. Either way it causes stress to the coupling of hands. If this imbalance gets too great the coupling breaks!

With a stereo feed, because they are typically not the same signal, if you connect them directly it will cause a fight between the two.

To 'sum' a stereo feed the two stereo signals should be connected via a pair of resistors. Anything from a few 100's of ohms to a couple of 1000 ohms.

That said, the output from most devices will be current limited to protect the output device from short circuit. The simplest way to do that is to have an internal resistor in series with the output, this insures that it can never be overloaded and in turn this would provide the buffer to permit connecting a stereo output into mono.

The cable you specify may or may not have protective resistor built in. The diagram they show does not show the resistors but that doesn't mean they are not there. But it does specify that it is suitable for the purpose. So my best guess is that it will probably be OK. I'd suggest you get one and try it and if it sounds perfect good then it probably is perfectly good.

I hope that helps