XLR --> RCA cable with resistor?

[Coytee]

Seems I read back when I was making my cables that I have an impedence match (more voo doo words, for this dummy)

Anyways, I recall being told with said impedence mismatch, I'd lose my high end.

Well, I've got my cables, I don't have ANY resistors and my high end sounds fine. However, reading that again, has me wondering if I'm perhaps missing something and my current bliss is simply ignorance?

So, if you have a XLR to RCA patch cord, what's the story on a resistor and if you add it, WHERE and HOW do you add it?

[mark1101]

wondering if I'm perhaps missing something and my current bliss is simply ignorance?

You couldn't hear you bass bin buzzing either. []

[Coytee]

When I stop chuckling from you humilating me right there (rightfully so), I'm gonna drive down there & knock you silly lol

[]

[mark1101]

You know...it's not like I'm not busy today. But I just couldn't resist. That was just made to order Richard. Only joking of course[]

Hopefully, someone will answer your question. I look at pro stuff all the time and I never know what to think about those connectors.

[DrWho]

lol Richard...in that thread you wanted to make absolutely sure that you didn't have an impedance mismatch and everyone was trying to make absolutely sure you avoided it...I've connected stuff straight from RCA to XLR all the time without problems at normal listening levels...it becomes a larger issue when you try increasing the volume because the consumer source can't fully drive the pro gear.

[Coytee]

My reason for asking this is twofold, one for myself and the other is to get any answers out for someone who asked me a similar question. So, I guess you're saying that for the distances I'm using (or any/most home owners) there shouldn't be any issues wired as they are.

[Edgar]

Seems I read back when I was making my cables that I have an impedence match (more voo doo words, for this dummy)

Anyways, I recall being told with said impedence mismatch, I'd lose my high end.

Mostly it's a noise issue.  Balanced cables with unbalanced impedances do not reject common mode noise as well as if the impedances are balanced.  So if you have really long cables in a noisy environment (lots of dimmer switches, commutator motors, fluorescent lamps, etc.), you'll pick up noise.  But it will still be better than using a plain unbalanced RCA cable.

So, if you have a XLR to RCA patch cord, what's the story on a resistor and if you add it, WHERE and HOW do you add it?

See post 762412:  http://forums.klipsch.com/forums/permalink/762412/762412/ShowThread.aspx#762412

It's a lot more important when going from unbalanced outputs to balanced inputs than when going from balanced outputs to unbalanced inputs.

Greg

[Rivendell61]

As Edgar says here and in the other post....

If you are wired up with the twisted pair, shield tied to ground at the unbalanced end AND you have a very low output impedance going into high....should be fine: having created a balanced connection. If the impedances are less than ideal you could lose some CMRR. That resistor thing will then help. Here is a pic:

[Rivendell61]

I must have had a dyslexic moment.....

If you are going balanced to unbalanced just ignore my post above. As I understand it per Whitlock bal to unbal is more problematic because of the potential variety of balanced output circuits....

Mark

[Coytee]

It's a lot more important when going from unbalanced outputs to balanced inputs than when going from balanced outputs to unbalanced inputs.

Greg

Just to clarify the picture, I'm going from a Peach preamp (rca) to the balanced inputs of the Dx-38. From each balanced output of the DX to RCA's on each power amp. So, I've got something like 6 ic's that are all RCA on one end and XLR on the opposing end. Length of longest one is 10' or perhaps 15' at the MOST.

I don't outwardly notice a lot of noise although I did discover the other day (thanks Drew & Terry) that I DO have some slight hum coming out of the K402 horn. In defense of the hum, I DO have a plethora of wires simply jumbled together behind everything.

[marems]

Transparent Audio & MIT use resistors in their network boxes to "Tune" the cables to the specific length and to help aginst noise and hum.

[Guest " "]

Matching transformers would be better.

[Coytee]

Yes Fritzie, I've got one of the transformers. It's that exact thing that I'm trying to keep away from (extra cord, more wires laying around) Unfortunately, they need to be powered and I never thought of that.

On a side note, I WILL say that I found the boost in signal kind of interesting. I haven't listened to it enough to conclude if it's just the same as cranking my bass bins up by say 6 db's or if that extra boost, simply makes everything work better. (does that make sense?)

The speakers seemed to have more 'punch' to them when I was using it but it could have simply been a result of me not calibrating the HF/LF horns together. I might have ended up with the HF horn attenuated too much relative to the LF horn.