1. Register NOW and become part of this fantastic knowledge base forum! This message will go away once you have registered.

Balanced/Unbalanced Signal Routing???

Discussion in 'Recording' started by lostindundee, May 14, 2008.

  1. lostindundee

    lostindundee Active Member

    Hi there

    I searched and found some really good posts. However, I would like to get a bit of specific advice before I shell out on a job lot of cables and was wondering if some of you could impart some wisdom regarding balanced/unbalanced/stereo jacks? The following are things I think I know mixed with a question or two so please chip in where needed. Please!!!

    Okay....Here goes:


    1. Are Stereo leads which have 2 insulating rings on the jack always a balanced lead? If not, how can you tell the difference?

    2. Do Balanced cables have an advantage in recording over Unbalanced due to noise reduction?

    3. All mic cables with XLR>>>XLR connections are Balanced?

    4. My Audio Interface does not have XLR Inputs but has Balanced 1/4" Inputs/Outputs. Therefore, fairly short XLR>>>TRS Balanced cables would be best suited for linking the XLR Output of my Preamp to the 1/4" Balanced Input of my Audio Interface? Is it better to use a Balanced TRS over an Unbalanced if the Audio Interface in question accommodates Balanced? Or doesn't it matter too much?

    5. Isn't a guitar's output signal Unbalanced, meaning that a Balanced lead in any guitar's output would just behave like an Unbalanced?

    6. If recording guitar directly, then TR/S Balanced/Unbalanced from Guitar>>>XLR Input on Preamp is NOT dooable and that a DI box would be required to convert the signal to Balanced. Am I correct here?

    Just needing a bit of clarification on the above as some of the cable things I've been reading just confused me as did Wiki. Any advice would be much appreciated.


    Kindest Regards

    LiD
     
  2. Link555

    Link555 Well-Known Member

    1) No. It could be two unbalanced signals or one differential (balanaced) signal. How can you tell? Read the manual.

    2) Yes if you have longer cable runs or are recording in a electrically noisy enviroment.

    3) Typically yes, however it is up the designer, you could use XLR to run 2 mono singals (LEFT and Right) on one cable.

    4)Yes. And Yes its better to run balanced for the reasons in question 2 's answer.

    5) Yes to both questions.

    6)Some Pre amps will allow you to use unblanced signals on thier inputs.

    Hope this helps,
     
  3. Codemonkey

    Codemonkey Well-Known Member

    6) Never had a problem with this. Well, besides the fact that it's unbalanced and the noise caused by that fact.
     
  4. lostindundee

    lostindundee Active Member

    It did help. Thanks Link555 :D

    The preamp I'm currently saving for is the Neve Portico 5012. I'm almost 6 weeks from buying it now. Phew. Anyway, looking at the back view of it, it appears to have an XLR in/out for each channel which is a shame really as the DPA 1073 has combination XLR/TRS. Therefore, I think I'll be using a DI box with the 5012. Is converting from an unbalanced to balanced what a DI box does basically?


    Thanks Codemonkey

    Ah...so you think there could be noise issues avoided by opting for balanced?


    The trouble with purchasing 1/4" leads is that hardly any that I have come across online specify whether or not they are balanced, unbalanced. Some state that they are stereo but I now realise that this may not mean anything. It's a minefield. You'd think an important aspect of cable/lead sales would be to list the balanced/unbalanced characteristic as one of its foremost features. GGrrrrr.

    Also, can anyone think of any decent lead/cable manufacturers which sell in the UK. Brands like Mogami and Canare are proving difficult to source from UK online outlets and buying from overseas carries duty tax.


    Kindest Regards

    LiD
     
  5. Link555

    Link555 Well-Known Member

    So are you pluging a GTR into the 5012?
    If so why not go for 5016 instead?
     
  6. Kev

    Kev Well-Known Member

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

    http://www.rane.com/note151.html
    http://www.rane.com/note110.html

    and there is more there to read

    . read it all
    . unscrew/disassemble the connectors and look
    . use a continuity tester to check what is connected to what

    there is also the issue of impedance and level matching
    read up on Gain Structure.

    this one might be heavy going but there is some worthwhile concepts about impedance, load, inductive reactance, frequency and RF interefance that is worth having in the back of your mind even if you don't understand all of it
    http://www.rane.com/note165.html
     
  7. Boswell

    Boswell Moderator Distinguished Member

    Hi LiD,

    Check this topic for info on balanced/unbalanced/instrument inputs:

    (Dead Link Removed)

    If you are determined to have the Neve name and want one mic channel plus one instrument channel, go for the 5016 instead of the 5012. Otherwise get the 5012 and a good DI box. Do not even think of trying to connect the guitar to the XLR inputs directly or via cable adaptors.

    Neve is not the only fish in the sea. I can recommend the DAV BG1U 2-channel pre-amp, one channel of which can be switched to be an instrument input. This gets you the best of both worlds, and a really clean, top-quality UK-built pre-amp as well.
     
  8. Kapt.Krunch

    Kapt.Krunch Well-Known Member

    May I suggest "kudos" to Lost for doing the research and supplying relevant info? Good to see some people do their homework before posting to allow for quicker and more focused responses. :wink:

    Generally, if a sealed cable is TRS on both ends, you can assume it's balanced, and that it's wired properly.

    If it's got removeable plugs soldered on, you can assume, but never hurts to verify. Someone may have wired it incorrectly, or may have done a bal/unbal mod.

    Same for XLR-XLR. Never hurts to verify.

    And, an XLR-TRS may have been modded for bal/unbal. Verify.

    In fact, it never hurts to verify ANY cable before use so you don't spend time wondering what's wrong.

    Always check your manuals for the proper balanced wiring. Some older stuff, especially, has pins switched around. Verify.

    Most devices these days will automatically switch internally to an unbalanced signal at its input, if you plug in a TS cable, but read the manual to verify.

    And some will allow you to physically switch between -10dBV to +4dBu, and you would use those accordingly. (Notice the different dB designations? dBV and dBu? Read up on those. This may have been linked to one of the Rane articles already, but if not, search for it in the Rane site).

    Good luck, and have fun.

    Kapt.Krunch
     
  9. Codemonkey

    Codemonkey Well-Known Member

    FWIW, a stereo 1/4" lead electronically is the same as a balanced mono lead. The equipment just uses pins 2 and 3 differently in each application.

    Balanced reduces noise if there is any picked up on the cable. Say your cable runs 70' with no shielding, you get HF loss, radio interference (a different station on every channel :)) and also hum and buzz.
    By having a balanced connection, you can blitz the lot of this. I think the HF loss still stands but, I doubt you have an 50' cable run in your studio.
     
  10. lostindundee

    lostindundee Active Member

    Thanks Link555

    Ah..you know something? For some reason, I missed the 5016 after looking at several of the other models in the range and just thought it was an EQ model or something similar. I was thrown slightly by another post on a different forum where someone posted that they wanted a 5012 but didn't want to go via a DI. Someone replied to this and said tough luck and that this was their only option. They were obviously not in the know and nor was I....lol...I guess I'll have to be careful in future about accepting some folks' answers as informed advice and do a degree of my own digging.


    Thanks Bowsell. as ever a wealth of sensible advice :D

    I read your response on the thread you linked to. It gave me a lot info. I may need to read it several times though...lol. Thanks for that.

    As for 5012 or 5016. I reckon for the sake of versatility, I may edge towards the 5012 with a good DI box or even a dual channel DI Box in case I have to record 2 guitars. I did consider the 1073 DPA at one point but I'm not sure it's worth the extra £700/$1370 with regard to sound. It does appear to have line inputs for each channel though. However, a DI box is much cheaper than the difference in price.

    As for the DAV BG1U 2. No kidding, it is the best of both worlds and I read a 2 really good reviews of it. It's another one added to my list of possibles along with the API lunchbox you suggested looking at. API certainly seem to be up there in the good stuff. I liked their accoustic sound on the listening sessions. Very warm.


    Thanks Kev.

    Now that's what I call technical...lol. My eyes are playing football just now due to a 12 hour shift at work. I've read one and intend reading the rest tomorrow or Saturday. Thanks also for the advice on checking connectors.


    Thanks Kapt.Krunch

    You've all given me so much to learn. I won't waste ANY of the good advice and pointers towards other sources. :D


    Thanks Codemonkey.

    I actually bought this intrument cable from a local shop last week. I asked for a balanced lead. However, now knowing that a guitar gives out an unbalanced signal I know this doesn't matter. According to the info on the box, the cable has a sheilded end and a non sheilded end. The box does not say the word balanced anywhere on it. Therefore, might one just assume that it's a stereo lead and nothing more.


    Kindest regards and a very appreciative thank you.

    LiD
     
  11. Link555

    Link555 Well-Known Member

    If your looking for a good DI, I would recommend a Radial. I have a JDI by Radial all passive, its very transparent to my ears.
     
  12. Codemonkey

    Codemonkey Well-Known Member

    "Therefore, might one just assume that it's a stereo lead and nothing more."
    Read what I said :p
    A balanced connection requires a ground, regular input and non-inverting input. Thus the cable has to have 3 wires inside it. A TRS lead used for stereo will use the Shield as the ground, and generally the Tip as the left channel, Ring as the right. Whereas, a TRS balanced connection uses exactly the same cable, but Tip becomes the Input, Ring becomes Inverting Input.
    Stereo and balanced cable is electrically the same - 3 wires from pin X to pin X. It's just that each of the wires inside the cable is used differently.

    (If I'm wrong, btw, will someone PLEASE tell me in very large bright red bold lettering)
     
  13. Boswell

    Boswell Moderator Distinguished Member

    Black lettering, but proper unbalanced stereo leads using single XLR connectors have two separate screens with signal conductors - the signals are not both running side by side inside the same screen as in a balanced lead.
     
  14. lostindundee

    lostindundee Active Member

    Ah...thanks Link555, I was just about to ask about good DIs :D

    I guess passive is best because it won't add colour to your guitar's natural sound. Is that the main reason for going passive? I suppose it saves an additional power source being required. Ahhh....before I go and get a 5012 and DI(s), I've just investigated a few things and realise that....

    I'm not using $$$ in the example below as the exchange rate doesn't transpose to anywhere near accurate US prices for the said items.

    ....if I bought a 5012 (roughly £1100) and was to add say a dual channel JDI Duplex. A friend and I like to record the odd blues guitar jam you see. This pushes the price up to £1400. Anyway, I can get 2 x 5016s from a stockist I know for £1500. I would definitely go for the 5016s here as they obviously provide 2 mic inputs and 2 DIs simultaneously. Well worth the extra £100. :D


    Thanks Codemonkey

    Apologies...lol. I was very very tired last night but got some time to read lots of stuff today and I think I'm getting the hang of it now. :)



    Thanks Boswell :D


    Regards

    LiD
     
  15. Link555

    Link555 Well-Known Member

    yep good call, I would say. A JDI is a just a jenson transfomer anyway. The neve version, will be just as good I am sure.
     

Share This Page