XLR male-female vs XLR--> 1/4 inch

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tonypham

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Has anyone noticed a difference in mic recording when using XLR to XLR cord vs an XLR to 1/4" cord?
 
Yes.


One is an XLR to XLR and the other is an XLR to 1/4". :)

;)


What kind of difference are you asking about?
Are you talking about a TS 1/4" or a TRS 1/4"?
If it is the latter, there's no difference as far as balanced signal transmission....they are just different types of connectors but able to pass/make the same kind of electronic signals.
 
all TRS cables have two bands right? in that case i think my 1/4inch plug is a TS cable. would the XLR --> XLR be better then?
 
AFAIK the XLR has a third pin for phantom power. If you don't need phantom power then I would think the XLR or 1/4 " should sound the same. I have a really old shure mic with 1/4" cable and it works/sounds just as good as my SM58.
 
If the mic has a an XLR connector, it's meant to run balanced. By using a TS 1/4" connector on one end, you will disrupt/unbalance the mic's signal path.
It might still work but could be noisy.
 
tonypham said:
okay i'm getting conflicting answers.
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Miroslav is correct, three conductors at both ends is for balanced connection. Balanced signals are more noise resistant and, assuming low impedance, travel over long lines better. Phantom power is a secondary issue. It normally only works on XLR, but you only need it for condenser mics, active direct boxes and the like. Dynamic mics, with one or two exceptions, don't use phantom.

Using unbalanced may sound the same or may sound noticeably degraded compared to balanced, depending on the characteristics of the input it's connected to. It may also pick up more noise.
 
why do some microphone manufacturers sell their mics with XLR --> TS 1/4 inch cords?
 
a specific example would be required for anything other then pure speculation

as majority of mics I've purchased (other then tube) over the last 'x' number of yrs have not include cables simply could do nothing but speculate

XLR, when introduced, was not merely noise canceling (of primary interest for cable runs of over 50 ft., even at 50 ft. a cable typically will not be picking up enough noise to benefit from the xlr design) and capable of carrying current necessary to power condenser mics but was designed to distinguish among certain impedance situations. When I first got started it was not unusual for entry level bands to use guitar amps (for example) for vocal reinforcement. In several incarnations I ran my limited vocal contribution through the same amp I used for guitar, via dual channels and separate controls. The mics I used, including a Unidyne branded early SM57 variant, not only had 1/4 plugs on one end but had different impedance then mics I bought just a couple of years later. the Unidyne did come with an appropriate 4 pin to 1/4 in. cable. The Altec mic that I bought a couple of yr later was XLR at the mic but since I used it primarily for harp (harmonic) I plugged it into a small guitar amp via a cheap transformer (with xlr socket and male 1/4 in.) But it was my introduction to XLR.

The first PA any band I was in ever owned had rotary volume controls and 1/4 in. jacks for mics. It was powered and introduced a level of noise that would be considered inappropriate today. During short life span of that band we already started to buy mics with XLR interface and used them with same cheap transformers I used for the harp.

Main point is that manufacturers, retailers include crap because they think it will help sell the product . . . if it is not required for product use and they can get away with it they will not include the crap. But 'why' specific crap can be a marketing mystery
 
That's pretty much it; a lot of PA gear used to only have 1/4" high impedance inputs. Being essentially the same characteristic as a guitar, that makes the mic similarly noisy. So balanced, low impedance is always better unless all you have to plug into is a guitar amp. A lot of old Shures and such are selectable between different output impedances; when used with a guitar amp you'd use a XLR-->1/4" cable, and switch the mic to high impedance.

There is no reason to use anything but XLR in a studio, or even in live sound now.
 
ido1957 said:
AFAIK the XLR has a third pin for phantom power. If you don't need phantom power then I would think the XLR or 1/4 " should sound the same. I have a really old shure mic with 1/4" cable and it works/sounds just as good as my SM58.
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The point of XLR cables is not to have a third pin for phantom power, but to run in balanced operation. The cable carries both the normal signal, and on another wire it carries the signal in reverse polarity. Third wire is ground. The reason for the reverse polarity signal is that any noise introduced into both the normal and reversed signals will automatically be canceled out.
 
that's interesting. does anyone know where i can go read about the physics behind the noise cancellation between the two wires?
 
tonypham said:
that's interesting. does anyone know where i can go read about the physics behind the noise cancellation between the two wires?
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Simple. Combine any signal with its polarity-inverted twin and it cancels perfectly.

Balanced lines have two versions of the signal, one normal (positive or hot) and one with its polarity inverted (negative or cold). At the destination the cold one is inverted again rendering it identical to the hot. Any noise that gets in is on both hot and cold, but at the destination the cold is inverted, so the signals match and add but now the noise is of opposite polarity and cancels out.
 
It's actually not necessary for signal to be on both wires, so long as there are two wires with the same impedance to ground any induced noise will be canceled by a receiving differential amplifier or transformer.
 
There is no reason to use anything but XLR in a studio, or even in live sound now.
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Other than some preamps and other outboard gear which only give a 1/4" line out option. Go balanced though. XLR if you can, TRS if you have to & TS if that's your only option. It does make a difference.
 
mshilarious said:
It's actually not necessary for signal to be on both wires, so long as there are two wires with the same impedance to ground any induced noise will be canceled by a receiving differential amplifier or transformer.
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You're right. My explanation was overly simplified to boot, which is kinda what I was going for but whatever...

I found a good explanation on how this works in the Wiki article entitled: "Balanced audio"

Differential signaling

Signals are often transmitted over balanced connections using the differential mode, meaning the wires carry signals of opposite polarity to each other (for instance, in an XLR connector, pin 2 carries the signal with normal polarity, and pin 3 carries an inverted version of the same signal).

Despite popular belief, this is not necessary for noise rejection. As long as the impedances are balanced, noise will couple equally into the two wires (and be rejected by a differential amplifier), regardless of the signal that is present on them.[1][2] A simple method of driving a balanced line is to inject the signal into the "hot" wire through a known source impedance, and connect the "cold" wire to ground through an identical impedance. Due to common misconceptions about differential signalling, this is often referred to as a quasi-balanced or impedance-balanced output, though it is, in fact, fully balanced and will reject common-mode interference.

However, there are some benefits to driving the line with a fully differential output:

-The electromagnetic field around a differential line is ideally zero, which reduces crosstalk into adjacent cables.
-Though the signal level would not be changed due to nominal level standardization, the maximum output from the differential drivers is twice as much, giving 6 dB extra headroom.[1] (if the amplifiers are identical, though, their output noise sums to 3 dB more than a single amplifier, decreasing dynamic range).
-Noise that is correlated between the two amps (from imperfect power supply rejection, for instance), would be canceled out.
-At higher frequencies, the output impedance of the output amplifier can change, resulting in a small imbalance. When driven in differential mode by two identical amplifiers, this impedance change will be the same for both lines, and thus canceled out.[1]
Differential drivers are also more forgiving of incorrectly wired adapters or equipment that unbalances the signal by shorting pin 2.[1]
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Jim Lad said:
Other than some preamps and other outboard gear which only give a 1/4" line out option. Go balanced though. XLR if you can, TRS if you have to & TS if that's your only option. It does make a difference.
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Microphones, dude, we were talking microphones. Otherwise, there is no difference between XLR and TRS, my entire rack is wired TRS (even the preamp; all my wiring is in-wall so I terminate everything in the rack to TRS).

TheGuitarMan said:
You're right. My explanation was overly simplified to boot, which is kinda what I was going for but whatever...

I found a good explanation on how this works in the Wiki article entitled: "Balanced audio"
Click to expand...

All good except for the bit about headroom--adding 6dB of "headroom" at an output takes away the same amount of headroom from the system.

For example, let's say all gear runs on a +/-15V (just stipulate that for me, OK?). Also assuming perfect rail-to-rail operation, that will yield a maximum output of +20dBV. We can add 6dB of level (not headroom) by sending that unbalanced out to an inverting amp, now we have +26dBV.

What happens at the next stage? A differential amp, such as an opamp, will try to put the difference between its inputs at its output. If it only has one input, say +15V, it puts +15V at its output, and -15V as -15V, etc.

But when the noninverting input is +15V and the inverting input is -15V, it will attempt +30V at its output--except it can't, because its power supply only goes to +15V. So that piece of gear can only tolerate a +20dBV maximum input, but you are sending it +26dBV. That's not my idea of headroom; headroom is CYA if you have an accidental peak, but this problem will bite you in the butt if you actually try to use the additional level.

Thus, for an electrically balanced system to maintain headroom throughout, you'd have to double voltage supply at each successive piece of gear.

Or just turn down the first stage so you don't clip the chain.

Transformers avoid that problem . . .
 
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