Audio connection help needed

[glocke]

I have a pair of KRK V6 studio monitors that I am trying to hook up to my imac.  The monitors have a sing 1/4 jack in the back of each.  I tried using cable that has 1/8 jack on one end (this goes to the headphone jack on my imac), with two RCA jacks on the other end that I put RCA tp 1/4 adapters on, which than get plugged into the monitors.
 
The problem is that when the 1/4 plugs are firmly seated in the monitors, there is no audio.  It is only when I back the 1/4 plugs out of the jack a little bit that I get audio, but this results in the 1/4 plugs sitting loosely in the jacks, (IOW they tend to fall out).
 
Is there another cabling method I can use ?  All the connections I am using are Radio Shack.

[David Houck]

I think the problem in not with the method, but with the connectors.
 
Try plugging something else into the monitors, like your bass, using a regular 1/4 instrument cable.  If it works, then the problem is not the input jacks on the monitors, it's the Radio Shack adaptors.  If it doesn't work, then there is something wrong with the input jacks in the monitors.  My guess is the Radio Shack adaptors.  I see that the KRK uses Neutrik Combo connector inputs, so again I'm thinking the problem is the Radio Shack adaptors.

[matthew90046]

I have the same monitors.  The reason that you need to pull back on the the 1/4 jack is because they are not mono jacks.  They are balanced stereo jacks (tip, ring, and sleeve).  When you push the mono in all the way you are shorting out the signal.  Pulling back on them fixes the problem... sort of.  Try to find a RCA to stereo 1/4 jack.  That should do the trick.  
 
The best option would be to get a little Mackie mini mixer and run your iMac to that and use the mixer's XLR outs to the V6's XLR inputs.  This also opens up more sources to your speakers.

[matthew90046]

And one more thing...
 
I have my Mac going to a Mackie mixer from the mini jack.  With some computers, not all, you can get horrific ground problems.  When I first set up my studio I could hear the hard drive through the speakers. It was just like the sound of a car motor through an AM radio from 1965.  If you get this problem go to your local car audio shop and get a car ground lift box.  They are around the same size of a match box with RCA inputs and outputs.
 
good luck
 
(Message edited by matthew90046 on January 24, 2008)

[David Houck]

Matthew; I don't quite understand your explanation.  Shouldn't he be using a stereo RCA jack at the imac end that splits into two mono cables ultimately ending in 1/4 mono jacks?

[glocke]

thanks for the advice....
 
As for the idea of a Mackie mixer, I have been thinking of getting someting so that I can do some recording on my imac.  Ive been looking at something like this:
 
http://www.guitarcenter.com/M-Audio-FireWire-410-Computer-Recording-Interface-102322666-i1154082.gc
 
Any other suggestions/advice?

[keith_h]

Dave,
Looking at the KRK V6 specs they are self-powered monitors that use balanced XLR and 1/4 TRS connector inputs. This means he needs to go from and unbalanced RCA to balanced TRS.  
 
Keith

[matthew90046]

davehouck,
 
The inputs on the KRK V6 speakers are Switchcraft XLR - 1/4 combos.  The XLR is obviously balanced, but the 1/4 is also balanced (tip, ring and sleeve).  At least that is what is on my pair.  
 
If you plug in a 1/4 mono into the speakers input you short out the connection between the ring and sleeve connections.  (I made a pic, but I can't upload now) :-(
 
To be honest, I don't even know if Radio Shack even has that sort of connector.  If it is made, Pacific Radio in Los Angeles would have it.  They have everything.  I make all my own cables and connectors so I have more options than most.  In this case I would make RCA to XLR cables using Canare balance cable.  On the RCA end I would simply not connect the 3rd pin wire.
 
(Message edited by matthew90046 on January 24, 2008)

[matthew90046]

Gregory,
 
I have been using ProTools for around 10 years so I am a little biased.  I think that the ProTools software is by far the best on the market, especially if you are using a Mac.  If you don't have a big budget I would look at the Mbox 2 line.  
 
 
http://www.digidesign.com/index.cfm?langid=100&navid=104&itemid=23596&ref=mbox2f-hp

[glocke]

thanks Matthew...My budget is kinda small, but my needs are simple.  I just need to record bass tracks over prerecorded guitar tracks.
 
As for the cable, if youd have any interest in making something like you described in your post, contact me offline.  Id reimburse you for all parts, and your time and labor.

[matthew90046]

These guys have all the cables you need...  
I don't have a good return policy.  ;-)
 
http://www.cablestogo.com/product_list.asp?cat%5Fid=2029&cm_mmc=AdWords-_-07-GOOD-_-1%2F4+to+xlr_779003001-_-1%2F4+to+xlr_Broad_%7C-%7C100000000000000127091&gclid=CLy5stzXj5ECFQ66PAodJFNZHw
 
They have RCA to XLR if you want to go direct from your iMac.  Or if you get the M-Audio box they have MONO 1/4 to XLR.  (The outs on the M-Audio 410 are unbalanced tip/sleeve.)

[glocke]

thanks dude....just called and got a qoute for a cable with a 1/8 male on one end and two 1/4 stereo plugs on the other end.  When I told the guy what I wanted to do, that was what he recomended.  Will that setup work?

[matthew90046]

That should work if you do not plan on doing any recording.  If you plan on using an interface you should get cables that work best with the unit.
 
I looked up some of the M-Audio products and the one that looks best for what you want to do is the FireWire Solo.  It is only $200 and has balanced outputs which is perfect for the KRK speakers.  That way you can go male TRS (stereo 1/4) to male XLR and stay totally balanced.  By the way I highly recommend using the XLR input instead of the 1/4 input.  They lock in and it is just, well... better.
 
This is my best recommendation...

[glocke]

Thanks man!  Gotta admit, the alembic boards have the some most helpful and friendliest people around!

[David Houck]

Thanks Matthew and Keith; I missed the TRS first time through.
 
(Message edited by davehouck on January 24, 2008)