1/4 or xlr?

[Jeff Mack]

I asked this before and got an answer but need to understand why. I have a couple of Senn wirelss systems that I carry in a portable rack with my digi 003. Now the senn receiver has a balance xlr out AND an unbalanced 1/4. I was told to get a xlr to 1/4 cable and go into my line input into the digi 003.

My question is why would they put an xlr out on the receiver? And why not come out of the xlr into my xlr input on the digi which opens up the last question (since I can get the signal that way) how do I know when to use the mic or di input on the digi?

Jeff

[Martin Mayer]

Originally Posted by Jeff Mack

My question is why would they put an xlr out on the receiver?

Because many cameras, mixers or recorders only have XLR inputs?

[Jeff Mack]

So the question that I still have is how do I know the senn's xlr out is mic or line level?

[Seth Bloombaum]

Originally Posted by Jeff Mack

So the question that I still have is how do I know the senn's xlr out is mic or line level?

Specifications that you could find at sennheiser.com or in your user manual, I'd think. Or, plug it into a mixer via xlr and see how much gain needs to be added to get good indications on the meters.

If it is line-level output, and your digi requires that to be on a 1/4" input, most likely what you want is an XLR-female to 1/4" TRS male (TRS=Tip-ring-sleeve). This will preserve a balanced signal from your receiver, which would be best-practice.

[Martin Mayer]

Originally Posted by Jeff Mack

So the question that I still have is how do I know the senn's xlr out is mic or line level?

Well, if it's the EK500 receiver, you can set the AF OUT level from +18dB (line) to -24dB (mic), and anywhere in between in 6dB steps. I'm sure the other Sennheiser receivers are similar. With respect, this is in the manual?

[Jeff Mack]

It's the G2 EW112. It says both outputs are common. The transmitter has -10,-20- and -30 db in it's signal setting and now I just found out that the receiver has an adjustable setting as well in 8 steps. I missed that originally.

I still can't get my head around whether to use xlr or 1/4 for mic/di on my digi 1-4 inputs or simply the 1/4 on 5-8 line inputs.

Sorry if this is a basic question but I have gone too long without knowing why to use which one.

Thanks everyone.

Jeff

[Paul R Johnson]

Don't get het up - 1/4 inch jacks and xlrs can both be used for mic, line or any level in between. Given the choice, I'd simply use an xlr-xlr to connect to the mixer, or the camera because I have plenty of them! The other plus points are that they lock. The balanced, noise rejecting properties aren't so critical once we get above line level anyway. Jacks will do the job, direct into the line level input. Having a choice just gives more options. The Sennheisers have an output that will go happily into an input expecting a traditional mic level, or a line level - using the mixer/camera input gain to sort out the exact match.

The 100 series only had the jack output, and many people just stuff a 1/4" to xlr adaptor in the socket and leave it there, or just wire up a jack to xlr short cable- makes no practical difference. The mixer will either have an input pad, or a pre-amp gain capable of the gain required, and most cameras have a mic/line switch that does the same thing,in just two cruder steps. The best signal to noise ratio is found by running the Sennheiser output hot into a line level input that is matched to something like a guitar or keyboard - NOT a proper line level signal such as CD/MD players. Most mixers that have a socket labeled "Line" stil need a bit of gain adjustment range to cope with a feeble guitar or hot pro-level playback unit at +4dB. Any mismatch in the gain settings is easy to hear, and see on the meters. On my cameras, I start with the XLRs switched to line, and look at the levels - if they are weak, then a switch to mic usually solves this one.

[Shaun Roemich]

Originally Posted by Jeff Mack

It's the G2 EW112. It says both outputs are common. The transmitter has -10,-20- and -30 db in it's signal setting and now I just found out that the receiver has an adjustable setting as well in 8 steps. I missed that originally.

I still can't get my head around whether to use xlr or 1/4 for mic/di on my digi 1-4 inputs or simply the 1/4 on 5-8 line inputs.

Sorry if this is a basic question but I have gone too long without knowing why to use which one.

Thanks everyone.

Jeff

The truth of the matter is: Use whichever you feel like. Sennheiser has been kind enough to supply line AND mic level signals to accommodate both camera installs as well as PA installs. I PERSONALLY would use line SOLELY because of a thinly held belief that the greater output voltage is less likely to be influenced by cable length/quality, RF interference etc with the caveat being that the line level signal be balanced (TRS, not TS) or else I reverse my decision completely. Oh, and then throw into the mix that I may decide to quickly change the wireless receiver for a handheld mic at mic level so maybe I should use the mic level output...

See what I mean? Options are good. Have fun with them and let your EARS be the judge.

[Ty Ford]

Originally Posted by Shaun Roemich

..the greater output voltage is less likely to be influenced by cable length/quality, RF interference etc with the caveat being that the line level signal be balanced (TRS, not TS) or else I reverse my decision completely. Have fun with them and let your EARS be the judge.

+1

Regards,

Ty Ford

[Jimmy Tuffrey]

I'd just like to bang on about un-balanced cables being fine for short runs. ( short being as much as 10 meters). Mainly because everyone seems to consider them to be some sort of gremlin. Many massive systems I have come across and built have had un-balanced insert paths amongst other things. Aome mic's have un-balanced cables built in to them too and although not a first choice; they sill work OK.
I really do feel that us happy folks here at DVI seem to be propagating an unreasonable aversion to the old fashioned two wire (un-balanced) approach.

[Bob Grant]

Originally Posted by Jeff Mack

It's the G2 EW112. It says both outputs are common. The transmitter has -10,-20- and -30 db in it's signal setting and now I just found out that the receiver has an adjustable setting as well in 8 steps. I missed that originally.

I still can't get my head around whether to use xlr or 1/4 for mic/di on my digi 1-4 inputs or simply the 1/4 on 5-8 line inputs.

Sorry if this is a basic question but I have gone too long without knowing why to use which one.

Thanks everyone.

Jeff

Probably the most critical setting is the transmitter's gain setting, that's the one to worry about from my experience. Set it for the least attenutation without overload, watch the display on the transmitter. If in doubt setting it 10dB lower than ideal is better than 10dB too high, if you overload the transmitter you're in big trouble.

[Ty Ford]

Bang on all you want Jimmy. Many people fly in the face of science. You won't be the first. Perhaps if all that science hadn't been driven deep into my head so many years ago, I'd bang with you. Sure, I've run unbalanced. I had an unbalanced patch bay for years and still have some unbalanced stuff with which I have few problems.

But the science says:

1. The common mode rejection cancels noise.
2. The double-sided circuitry delivers 6dB more signal.
3. Running a separate ground also removes other noise possibilities.
4. Unbalanced connectors are frequently wonky, not providing as good a mechanical connection as balanced hardware.

Regards,

Ty Ford

[Jimmy Tuffrey]

Originally Posted by Ty Ford

Bang on all you want Jimmy. Many people fly in the face of science. You won't be the first. Perhaps if all that science hadn't been driven deep into my head so many years ago, I'd bang with you. Sure, I've run unbalanced. I had an unbalanced patch bay for years and still have some unbalanced stuff with which I have few problems.

But the science says:

1. The common mode rejection cancels noise.
2. The double-sided circuitry delivers 6dB more signal.
3. Running a separate ground also removes other noise possibilities.
4. Unbalanced connectors are frequently wonky, not providing as good a mechanical connection as balanced hardware.

Regards,

Ty Ford

Oh I'm not disagreeing with the electronic facts. It's just that folks here seem to set so much priority on running everything balanced. Sure it is best but one can over stress it's importance and then people start thinking that if it's un-balanced it is no good. Particularly at line level un-balanced is not the end of the world. C.D. players. mini disc etc often have only phonos on but they are ok for the short sort of runs involved(5-10m for instance).

I've had trouble too with good quality XLR cables getting induced hum noise as well. Swapping them for star quad sorted that on that occasion.

For instance I have the Sony PCM D50 and I'm using the un-balanced line in and getting exceptional results. If it had an option for balanced XLR as well as standard, I would still use the mini jack for bag use. Not because it is better, I hate mini jacks, but because it is convenient, light and it works perfectly, especially with my nice 6 pin hirose -minijack lead (un-balanced).

Any way best regards, I'm enjoying the chat even though it is thread drift rather.

[Seth Bloombaum]

Originally Posted by Jimmy Tuffrey

Oh I'm not disagreeing with the electronic facts. It's just that folks here seem to set so much priority on running everything balanced. Sure it is best but one can over stress it's importance and then people start thinking that if it's un-balanced it is no good. Particularly at line level un-balanced is not the end of the world...

The original poster was confused on several issues related to the basics of patching equipment. Suggesting that he follow a "best practices" approach and run balanced is a good idea, in my opinion, as any of the problems that occasionally come up with short unbalanced runs would be difficult for him to recognize and troubleshoot.

I set up a small sound p.a. job yesterday that runs today - let's see, the cd player comes in unbalanced... the 6 wireless channels, the wired hand mic, and everything on the output side is wired balanced. Oh, except the output to the client's videoconferencing system, which has an RCA input. Of course I'm running balanced for 100' (33m), then a transformer (DI), then a 6' (2m) unbalanced cable to the videocon. If I had a shorter 1/4"-RCA handy I'd use it.

Unbalanced isn't a problem until it's a problem, then you're in a situation of trying to figure out whether you were using risk management appropriate to the situation. There are a million gremlins out to get us in sound work, and many of them are immediately tamed by using best practices. Which I do as much as possible, because there is always other stuff that comes up.

Ty's is a great summary of the science. Why should we care? Because someone is paying us to care, and when something does go wrong at a critical moment (and this does happen, even to the best of us) we want to be able to say "I did everything possible to avoid this, and we recognized the problem instantly and recovered from it quickly".