XLR/RCA

[Coytee]

Yes, another question about soldering them:

1. Is the sheath considered "ground" as in the black wire that would go to Pin 1 on the XLR? (my wires are sheath/white/blue)

2. The diagram I'm looking at has two ways to do it:

A: XLR = Pin 1 "black", Pin 2 "Red", Pin 3 "blue" / RCA = RED to tip (hot?) and black/blue BOTH to the ground/sleeve

B: XLR = Pin 1 "black" / Blue Pin 3 is shorted to Pin 1, Pin 2 Red / RCA= Black to sleeve, Red to Tip

Since I'm using some Mogami, I've got two stranded pairs and it's making it a bit more challanging for me since I need to snip them short, strip them while making sure that I don't mix strands between colored wire sets [:$]

This will be going into the Peach if that matters. The Peach has a high & low Z mode (don't know if that would matter)

Length will only be about 12"/18" as the Dx sits right under the Peach.

What dictates when you would use one format over the other??

Looks to me like both situations connect pins 1 & 3. Just a matter of connecting them on the RCA side or the XLR side with the shorting wire.

What would happen if you wired all three on the XLR side and on the RCA side, left the sheath hanging (ungrounded/unconnected)

This would mean, on the RCA side, only the (in my case) Blue and White wires are attached and the sheath is snipped short (and not shorted on the XLR side)

??

I'm asking, not because I plan to do it but I'm not sure that I didn't do it before. I will look at some of the wires. Would that cause hum issues?

[Coytee]

Pic 1

[Coytee]

2

[djk]

Try shield to pin 1, White to pin 2 and RCA tip, Blue to pin 3 and RCA shell.

http://www.rane.com/note110.html fig.17

This allows best performance if there are ground issues:

http://ebtechaudio.com/products.html

I have an HE-2, HE-8, and LLS-8 if you need to try one.

[Guest " "]

I don't like to short inverted and non inveret runs to ground (3 into 2 arrangement)....but if you have to do it....use some load resisters (100 to 600 ohms).

[Coytee]

This allows best performance if there are ground issues:

If that is similar/same to the Art Cleanbox, I'm already using one of those. I'd like to remove it from the system if possible.

Right now (with the Cleanbox and one/two cheater plugs) I don't really have any discernable hum. Only reason I'm redoing some of the wires is I have a handful of wires that I bought (couple of them dirt cheap, flimsy feeling type) and I've got a handful of lenghts left over from prewiring my house (using Mogami Neglex).

I figure since it's supposed to be nice wire, I'll just replace the cheapo's I've bought (and some of the first ones that I made when I first got the Jubilee's)

I ordered 10 new pair of Nutrik connectors yesterday and decided to maybe do the RCA end on a short pair since I already have four RCA connectors.

I remembered being easily confused when I did the XLR/RCA the first time. For kicks, I just now took the RCA end apart of one of the XLR/RCA wires I made (and am currently using). Seems I did short the two requisite wires on the RCA ground pin.

To be honest, I was suspecting that I had not. I have a distinct memory of taking something back apart (4 years ago) and snipping a wire in an effort to see if that got rid of some hum.

Guess I'll find out as I replace them. I'm a bit curious now.

[Coytee]

)....but if you have to do it....use some load resisters (100 to 600 ohms).

1. I'd have no idea if I would have to do that or not.

2. Where on earth would one place those? Simply in line? Stuff them into the headshell? Stuff them into the RCA end? I'm already Mr. Elephant Thumbs with regard to soldering

After I installed the Cleanbox, I read something about how it kills the bass response of the system and a certain capacitor needs to be replaced with a larger value to lower the frequency it allows through (or something like that)

Would those resistors do anything like that? (effect the sound)

[Marvel]

After I installed the Cleanbox, I read something about how it kills the bass response of the system and a certain capacitor needs to be replaced with a larger value to lower the frequency it allows through (or something like that)

Would those resistors do anything like that? (effect the sound)

No... (the short version) []

[Guest " "]

)....but if you have to do it....use some load resisters (100 to 600 ohms).

1. I'd have no idea if I would have to do that or not.

2. Where on earth would one place those? Simply in line? Stuff them into the headshell? Stuff them into the RCA end? I'm already Mr. Elephant Thumbs with regard to soldering

After I installed the Cleanbox, I read something about how it kills the bass response of the system and a certain capacitor needs to be replaced with a larger value to lower the frequency it allows through (or something like that)

Would those resistors do anything like that? (effect the sound)

there's no universal anser becuase there are so many possible ways of hooking xlr to rca. factors are how the inputs are loaded on the equipment with the gain stage. for example, some have seperate circuts for the inverted and noninverted runs of xlr, balanced end to end. some are tradition unblalnced channels which have a parterning RCA, but will use a transfomer to create a differential ground so that the 3 runs of an xlr can be properly loaded to the two runs of an rca connection ( the black boxes oftern have these). Another approach is to use resisters internally in the devices with the gain stage to create a differential ground which properly loads the inverted and noninverted runs of an xlr connection. So basically it depends on what the architecture ofthe input of your gain stage is....and as a general rule...if you select a 3 xlr connection to rca approach that involves shorting an inverted or noninverted signal run of your xlr connector, put a load resister on the xlr run you are directly shorting to ground. I would use a 600 ohm 1.4 watt resister in line, and heat shrink it. or buy the black box and not have to worry about it.

[CECAA850]

Shouldn't there only be 2 XLR pins connected when converting to RCA?

[Mike Dubay]

Some good reading on this.

http://www.rane.com/note110.html

Connections of pins 1 and 3 seem to depend on you hardware. I connected pins 1 and 3 on my RCA to balance XLR cables for my active crossover and got a ground loop, removing the connnection helped greatly.

The picture above is some type of transformer isolation, correct?

[DrWho]

Is your XLR male or female?

[Coytee]

Is your XLR male or female?

If I replace all of them, I'll have both.

XLR(male) / RCA

XLR(female) / RCA

[mark1101]

All you should need to do is make sure you don't have Pins 1 & 3 tied together. It's that simple. No clean box. God..........get rid of that noise box. Those are junk. You should not need it.

A Peach will not interface well to Pro gear. You are going to get lots of noise and weak output............the clean box doesn't fix it. Mark D. has mentioned several times his designs do not interface to Pro equipment. It was never an intent for them to..........and they don't..............You are going to have use something other than a Peach.

[djk]

"If that is similar/same to the Art Cleanbox, I'm already using one of those. I'd like to remove it from the system if possible."

No, the EBtech is passive.

"The picture above is some type of transformer isolation, correct?"

Yes, it is an above average transformer for an inexpensive device.

If you need the best:

http://www.jensentransformers.com/

"You are going to have use something other than a Peach"

http://ebtechaudio.com/llsdes.html

-10dB : +4dB matching.

[Coytee]

All you should need to do is make sure you don't have Pins 1 & 3 tied together.

Lil update:

I disconnected the wire to one of those leads (was it 1 or 3? I forget)

Regardless...I didn't SNIP the wire, just removed it. I plugged the system up with the XLR shell removed so I could ground the wire to the pin and remove it.

Long story short, I had tons more noise with the wire removed and 99% of it went away when I connected it (thereby shorting the two pins)

Go figure!

I've now removed the Art Cleanbox and put it in the back room.

If you stick you head 10 inches away from the bass bin you can sense some hum but it's VERYYYYYYYYYY low and from the seating position, you can't hear it at all.

This was not the case with the wire removed from the pin.

--------------------------------------------------------------

Side question... I've now received my Neutrik RCA's to put the IC's together.

I've seen a diagram (from Neutrik) where there is a SINGLE wire surrounded by the sheath. The sheath is soldered to the ground pin on the connector.

I've seen some other commentary here about using one pair (remember, I've got the 4 wire Mogami) for hot, one pair for ground and was told to float only one side of the sheath.

Would connecting both sides of the sheath create a potential ground loop?

If one side of sheath should be lifted, do I recall that it's the side sending the signal?

Meaning, the grounded end would be connected TO the output of the CD player. The grounded end would be connected TO the output of the DVD player. The grounded end would be connected TO the outputs of the Peach.

The end of the wire from which the signal begins would be the grounded end. (or is it the lifted end?)

I don't want to get into a situation of having to look each time I rewire to know which end is which since I don't have any arrows. If I should do it that way I might make all the grounded ends "red" and then I'd always know which end is which. I would not worry about red/white to designate left/right but rather, red would be a known end of the cable.

More thoughts?

PS: I'm heading to Tennessee for 12 days so any lack of my responding isn't me ignoring but rather, probably working on my Honey-Do list.

I hear it's approaching the length of a football field. []

[babadono]

Coytee,

I'm sorry I have joined this thread maybe too late but............

What exactly is it that you are doing? Are you: 1. Taking an unbalanced (RCA) output and feeding a balanced input (XLR)? or 2. Taking a balanced output (XLR) and feeding an unbalanced input (RCA)?

Babadono

[Panacea Engineering]

Under normal circumstances the shield is attached on the Source end of the circuit and Floated on the receiving end. Baba raises a good question as to where the balanced XLR's are in the circuit.......

W. C.

[mark1101]

Coytee, I beleive the main issue here is that you will never get good performance trying to interface a Peach to a pro audio amp. That's just a fact Mark D. has discussed. The Art clean box helps some, but really is not a good solution at all. It is degrading the signal and it definitely drops the low end off early. When I was using one, I did a capacitor mod that restored the low end, but the box itself just caused a degradation of signal and I eventually got rid of the equipment mismatch that caused me to need the box in the first place. The box is a band-aid. The issue is equipment mismatch.

In the case where you do not have a gross equipment mismatch and simply want to convert balanced to unbalanced (I.E. home audio to pro audio), the method of making sure Pin 1&3 in the XLR are not tied together should solve the issue. You can find this all over the internet. It is also in a few component manuals I have such as my Ashly Protea 4.8SP processor manual, and my Benchmark USB DAC manual.

I also remember you being in the room when someone named Roy showed us how to do this using an EV DX-38 processor being fed from a home audio preamp. Remember?

[DrWho]

Roy's mod to the Dx38 shorts the chassis ground to the audio ground, which is otherwise left floating to be compatible with typical balanced pro audio installations.

In a home audio setting, you should never have Pin 1 and Pin 3 disconnected inside the XLR. The only time you can get away with that is when you have a transformer coupled input. The in/out of the Dx38 uses servo balanced opamps...leaving one end floating will cause all sorts of noise.

Jensen has put together two great articles on this topic:
http://www.jensen-transformers.com/an/an003.pdf
http://www.jensen-transformers.com/an/an004.pdf

Notice there is no magical balanced output to unbalanced input adapator cable. For the unbalanced output to balanced input, Figure 2.1 "Minimal Adaptor Cable" is sufficient for short runs (ie, our applications).

When using the Dx38, you should use a balanced input amplifier after the unit, and if that's not available, then you should tap off the opamp buffer that comes after the volume control and totally bypass the entire servo balanced output stage. Sadly, the power supply and opamps chosen aren't sufficient for satisfying the noise floor demands of consumer voltages.