[fr3derick]

Hi Ray,

will you consider contacting Livewires too? Believe many would appreciate the inclusion of Livewires together with Westone, UE and JH. Thanks.

 

[Darwin022]

Quote:

Originally Posted by Ray Samuels /img/forum/go_quote.gif I am really working with some great manufacturers of IEMs to have them make the balanced cable for the IEMs that they manufacture. Also Whiplash is making me the very first balanced cable for the JH 13PRO. As I have mentioned before that I have 1000 connectors coming hopefully soon so I can devide them between JH Audio, Westone, Ultimate ear & Whiplash Audio, they will be making the cables for their own IEMs & Whiplash will be making the after market balanced cable to those who would like his wire. Cheers. Ray Samuels

This is interesting, I've spoken to UE and JH Audio on separate occasions and they've both indicated that they don't make their own cables. UE specifically said that they didn't; JH implied it. I'd be curious to see if they actually DO try to make cables themselves. Who knows, they might be more durable than the standards

Waiting for Whiplash to make a TWag balanced cable

 

[germanium]

Quote:

Originally Posted by tigon_ridge /img/forum/go_quote.gif ^The idea of a balanced cable is that each negative should have its own ground.

There is no ground on a balanced headphone cable only 2 hots of opposite polarity.

 

[Steve Eddy]

Quote:

Originally Posted by germanium /img/forum/go_quote.gif There is no ground on a balanced cable only 2 hots of opposite polarity.

"Balance" has nothing to do with signal polarity. What is "balanced" are the two impedances with respect to ground.

se

 

[germanium]

Quote:

Originally Posted by Koyaan I. Sqatsi /img/forum/go_quote.gif "Balance" has nothing to do with signal polarity. What is "balanced" are the two impedances with respect to ground. se

I corrected the post pertaining to the cable which I was too general to what I really meant though balanced even in the small signal cables does imply two signals of opposite polarity with respect to each other but there is also a single gound in such a cable & that is why there is 3 pins in an XLR or 3 contacts on a TRS connector meant for single channel balanced connection. The gound is not needed on a headphone cable but complete seperation of the 2 channels is required hence 4 wires instead of three & the use of 4 pin connectors is required for stereo earphones. By the way I corrected the post before I seen your post as I realized I was too general in that statement after rereading it myself.

The main benefit of balanced operation in the small signal domain is common mode noise cancellation & in order to achieve that oposite polarities must be used for the signal. External electrical noise from nearby electric fields would induce noise of the same polarity on both wires, by having the signal presented in oposite polarities they can feed the amps + & - terminals with the signals & the noise would get cancelled but the signal gets passed as the noise is in the same polarity but the signal on the 2 wires is in oposite polarity. Obviously the impedance to ground must be the same in this scenerio in order to work properly, But the signal must also be in oposite poplarity.

The main benefit of balanced operation of a headphone or speaker for that matter is increased drive capabilty. Sometimes it helps the sound if well implemented & sontimes it don't especially if poorly impemented. I've heard both examples. Operating at low voltages as this amp it would need all the help it can get with low sensitivity high impedance headphones in order to get sufficient volume. Most IEMs would not need such but may benefit from the extra headroom that running in balanced operation provides.

Yes I do in fact understand these things

 

[Steve Eddy]

Quote:

Originally Posted by germanium /img/forum/go_quote.gif I corrected the post pertaining to the cable which I was too general to what I really meant though balanced even in the small signal cables does imply two signals of opposite polarity with respect to each other...

There can't be two signals of opposite polarity with respect to each other. There is only the single, differential signal that exists between the two lines. To have two signals of opposite polarity, there must be a third point used for reference.

Quote:

...but there is also a single gound in such a cable & that is why there is 3 pins in an XLR or 3 contacts on a TRS connector meant for single channel balanced connection.

A third lead is not a requirement in a cable used for balanced interconnection. Two is all that is required for signal transmission.

The third contacts on an XLR, or TRS meant for single channel balanced interconnection, isn't for ground, it's for the shield/chassis, which may or may not be tied to signal ground (see "ground lift").

Quote:

The gound is not needed on a headphone cable...

Nor for interconnect cable.

Quote:

...but complete seperation of the 2 channels is required hence 4 wires instead of three & the use of 4 pin connectors is required for stereo earphones.

Complete separation isn't inherently required. It's only required in bridged circuits to prevent the output of one amplifier from driving the output of another. Balanced stereo outputs can be achieved using just 3 pins. Transformer coupled outputs for example would allow this.

se

 

[germanium]

Quote:

Originally Posted by Koyaan I. Sqatsi /img/forum/go_quote.gif There can't be two signals of opposite polarity with respect to each other. There is only the single, differential signal that exists between the two lines. To have two signals of opposite polarity, there must be a third point used for reference. A third lead is not a requirement in a cable used for balanced interconnection. Two is all that is required for signal transmission. The third contacts on an XLR, or TRS meant for single channel balanced interconnection, isn't for ground, it's for the shield/chassis, which may or may not be tied to signal ground (see "ground lift"). Nor for interconnect cable. Complete separation isn't inherently required. It's only required in bridged circuits to prevent the output of one amplifier from driving the output of another. Balanced stereo outputs can be achieved using just 3 pins. Transformer coupled outputs for example would allow this. se

Balanced output to the drivers is essentially bridging which does require complete seperation of the two channels. Almost all amps will blow if you dont do this as most are not even stable when the outputs are paralelled when driven with a mono signal of the same polarity (there are some that can but only driven with a mono signal). If exposed to a stereo signal even these in most cases would blow or at least shut down. combining two hots together from a bridged amp even of the same polarity is suicide for the amp as stereo signals are not always in phase with each other. Transformer coupling is somewhat of a different kettle of fish & what we are talking about is a amp that is direct coupled so what I'm saying here applies.

The gound lift is there to provide a means of preventing ground loops & this may be nessessary if both componants share a common ground at the power plug. The signal return is the provided by the grounded power plug if the ground is lifted at the signal plug. Other wise you would get massive hum. In any case there is still a return path for the signal. Even in transformer coupling there is a return signal path. the gounds though in this case are isolated.

I have also seen transformer coupled tube amps bridged & again the two signal paths to the speakers are completely seperate in stereo configuration though it may be possible to tie together in a feedback free amp as these can be stable in most situations as there is no negative feedback that would try to neutralize the signal coming from the other amp. If anyone could have done that it would have been my friend Jack Strayer & he chose not to provide an easy means to bridge on his amazing sounding class A1 limited zero feedback transformer coupled stereo tube amps. These amps were completely stable into any load including dead short. Distortion would have been high in this state but signal could be recovered through I/V conversion that was clean enough to listen to, but the amp would not go into any kind of oscillation.

 

[Steve Eddy]

Quote:

Originally Posted by germanium /img/forum/go_quote.gif Balanced output to the drivers is essentially bridging which does require complete seperation of the two channels.

"Balanced" is a balance of impedance. It's entirely possible to create a balanced output that's not bridged, that doesn't use transformers, and doesn't require the complete separation of the two channels.

Quote:

Transformer coupling is somewhat of a different kettle of fish & what we are talking about is a amp that is direct coupled so what I'm saying here applies.

Ok.

Quote:

The signal return is the provided by the grounded power plug if the ground is lifted at the signal plug.

How do you figure?

The safety ground gets tied directly to the chassis at the entry point. If you lift the signal ground from the chassis, how is the safety ground acting as any sort of signal return?

se

 

[Beefy]

Nobody cares, lads.

*unsubscribe*

 

[Steve Eddy]

Quote:

Originally Posted by Beefy /img/forum/go_quote.gif Nobody cares, lads.

You know, you're absolutely right.

*resign*

se

 

[germanium]

delete

 

[Steve Eddy]

Quote:

Originally Posted by germanium /img/forum/go_quote.gif I have actually had this happen before when both grounds on a single ended stereo pair of interconnects broke & the signal began returing by the power cord ground with virtually no ill effects of this happening. It was not something that I intended but it worked ok.

You're talking a completely different scenario here. First, you're talking about single-ended, not balanced. Second, your original statement related to when the signal ground was lifted.

Anyway, I'm through discussing technical issues here.

se

 

[jamato8]

Well I was enjoying the read. All over now? A new year's resolution? :^)

 

[Steve Eddy]

Quote:

Originally Posted by jamato8 /img/forum/go_quote.gif Well I was enjoying the read. All over now? A new year's resolution? :^)

Well, one usually makes their resolutions BEFORE the new year, but yeah, you might say that.

se

 

[grokit]

Quote:

Originally Posted by Koyaan I. Sqatsi /img/forum/go_quote.gif Anyway, I'm through discussing technical issues here. se

I thought it was an OK read myself, at least the parts I understood because there seems to be an ongoing debate about the difference between single-ended and balanced and I am trying to get my head around the advantage of having fully discrete channels and what makes them sound so damn good.

So where are you going to discuss it

?