The No.1 Website for Pro Audio
 Search This Thread  Search This Forum  Search Reviews  Search Gear Database  Search Gear for sale  Search Gearslutz Go Advanced
Unbalanced signal from preamp to converter. Bad?
Old 11th March 2012
  #1
Gear Maniac
 
ljona's Avatar
 

Unbalanced signal from preamp to converter. Bad?

One quick question, maybe it doesn´t need much discussion.

Can I get away with using unbalanced XLR-Jack connector from my
preamp to converter?
Does it affect the sound or noise floor?

I´m manly tracking loud sources like drums and guitar amps.

Friend of mine bought one and don´t like the idea it being useless.
Old 11th March 2012
  #2
Lives for gear
 
cavern's Avatar
 

You mean balanced XLR right?
The question is a bit vague.Which converter or do you mean interface.
XLR pre amp out to XLR pre amp in would be bad.
Old 11th March 2012
  #3
Gear Maniac
 
ljona's Avatar
 

Quote:
Originally Posted by cavern View Post
You mean balanced XLR right?
The question is a bit vague.Which converter or do you mean interface.
I mean unbalanced cable from SCA preamp to RME ADI-8 Interface.
Old 11th March 2012
  #4
Lives for gear
 
Granny Gremlin's Avatar
 

Read the manual - it will tell you if the ADI can take unbalanced in (probably does; RME is pretty solid like that, but check).

The worst case is that your signal would be a bit quieter than the preamp output due to unbal signal into bal input (probably not such a bad thing; hit the converters lighter and drive the SCA harder; more useful if you don't have the SCA's wired up for master volume, vs gain trim on the second pot).

Actually, the better question is if the SCAs will handle it - depends which ones you have (some transformer outputs for example don't like that, but will probs be fine). Ask on the SCA forum.
Old 11th March 2012
  #5
Lives for gear
 
cavern's Avatar
 

Unbalanced TS to TS cable would work fine if the pre amp doesn't have balanced TRS out,keep the cable short.
Better would be,a balanced XLR to balanced TRS cable though.
Old 11th March 2012
  #6
Lives for gear
 
Granny Gremlin's Avatar
 

Actually yeah; why are you using an unbal cable?
Old 11th March 2012
  #7
Gear Maniac
 
ljona's Avatar
 

Quote:
Originally Posted by Granny Gremlin View Post
Actually yeah; why are you using an unbal cable?
Friend bought it because we needed it but found out it was unbalanced.
I´m now using balanced cables but don´t like having it lying around doing nothing or worse, be useless so I´m asking.
Old 11th March 2012
  #8
PDC
Lives for gear
 

Quote:
Originally Posted by Granny Gremlin View Post
Read the manual - it will tell you if the ADI can take unbalanced in (probably does; RME is pretty solid like that, but check).

The worst case is that your signal would be a bit quieter than the preamp output due to unbal signal into bal input (probably not such a bad thing; hit the converters lighter and drive the SCA harder; more useful if you don't have the SCA's wired up for master volume, vs gain trim on the second pot).

Actually, the better question is if the SCAs will handle it - depends which ones you have (some transformer outputs for example don't like that, but will probs be fine). Ask on the SCA forum.
Why does an unbalanced cable not have the same output as a balanced cable? The OP wasn't necessarily talking about unbalanced, -10. You can have an unbalanced line level, +4 connection.
Old 11th March 2012
  #9
Gear Maniac
 
ljona's Avatar
 

Quote:
Originally Posted by Granny Gremlin View Post
Read the manual - it will tell you if the ADI can take unbalanced in (probably does; RME is pretty solid like that, but check).

The worst case is that your signal would be a bit quieter than the preamp output due to unbal signal into bal input (probably not such a bad thing; hit the converters lighter and drive the SCA harder; more useful if you don't have the SCA's wired up for master volume, vs gain trim on the second pot).

Actually, the better question is if the SCAs will handle it - depends which ones you have (some transformer outputs for example don't like that, but will probs be fine). Ask on the SCA forum.
I have used it and find no difference between balanced/unbalanced.
A guy recommended using balanced, then you don´t get ground problems.

My main concerns is ground problem and if it raises the noise floor using unbalanced.
Old 11th March 2012
  #10
Lives for gear
 
cavern's Avatar
 

Quote:
Originally Posted by ljona View Post
I have used it and find no difference between balanced/unbalanced.
A guy recommended using balanced, then you don´t get ground problems.

My main concerns is ground problem and if it raises the noise floor using unbalanced.
Noise won't be a concern with unbalanced if you keep the cable short.
If you can solder,just put a TRS connector at the end of an XLR cable and go balanced XLR from the pre amp to Balanced TRS at the RME.
I assume the SCA has XLR out?or no...
Old 12th March 2012
  #11
Lives for gear
Couple of considerations:

Balanced is primarily useful for noise rejection, not a problem with a short cable run and decent quality cable.

Using a balanced send to an unbalanced in means that you're losing 50% of the signal, a 3 dB loss which you'll have to make up. Shouldn't bring up the noise floor much, but it is there.

Running a balanced XLR connector from a preamp to a mixer or interface means that the signal is going thru two preamps, not really a great idea (of course, some interfaces don't allow you to bypass the mic preamp and just pad it down but that's another argument) so the best solution is balanced or unbalanced line out into balanced or unbalanced line in...
Old 12th March 2012
  #12
Lives for gear
 
cavern's Avatar
 

Quote:
Originally Posted by drbob1 View Post
Couple of considerations:

Balanced is primarily useful for noise rejection, not a problem with a short cable run and decent quality cable.

Using a balanced send to an unbalanced in means that you're losing 50% of the signal, a 3 dB loss which you'll have to make up. Shouldn't bring up the noise floor much, but it is there.

Running a balanced XLR connector from a preamp to a mixer or interface means that the signal is going thru two preamps, not really a great idea (of course, some interfaces don't allow you to bypass the mic preamp and just pad it down but that's another argument) so the best solution is balanced or unbalanced line out into balanced or unbalanced line in...
He has an SCA pre that has unbalanced TS out and an RME ADI-8 wich has only line level in balanced or unbalanced.
The ideal connection would be a balanced XLR to balanced TRS cable assuming that the SCA also has XLR out but he hasn't confirmed that yet.
If not,TS to TS and keep it short right?
Old 12th March 2012
  #13
Gear Maniac
 

Quote:
I mean unbalanced cable from SCA preamp to RME ADI-8 Interface
The ADI-8 has balanced TRS inputs. All you need is a an XLR to TRS cable. Make sure it connects XLR pin 2 to TRS tip for proper absolute phase.

Quote:
He has an SCA pre that has unbalanced TS out
There's no such thing. All of our modules have fully balanced outputs on XLR connectors. The A12, J99, and N72 have floating transformer balanced outputs. The C84, T15, and B16 use circuits that automatically add 6dB when either output is grounded.

Quote:
Friend bought it because we needed it but found out it was unbalanced.
You can use an unbalanced cable but it must connect XLR pin 3 to the shield. With electronically balanced outputs like those in the C84 and T15, you will lose 6dB of headroom.
Old 12th March 2012
  #14
Gear Maniac
 
ljona's Avatar
 

Thanks for the help guys - Seventh Circle Audio

LOVE yer work SCA!
Post Reply

Welcome to the Gearslutz Pro Audio Community!

Registration benefits include:
  • The ability to reply to and create new discussions
  • Access to members-only giveaways & competitions
  • Interact with VIP industry experts in our guest Q&As
  • Access to members-only sub forum discussions
  • Access to members-only Chat Room
  • Get INSTANT ACCESS to the world's best private pro audio Classifieds for only USD $20/year
  • Promote your eBay auctions and Reverb.com listings for free
  • Remove this message!
You need an account to post a reply. Create a username and password below and an account will be created and your post entered.


 
 
Slide to join now Processing…
Thread Tools
Search this Thread
Search this Thread:

Advanced Search
Similar Threads
Thread
Thread Starter / Forum
Replies
natibuck340 / Remote Possibilities in Acoustic Music and Location Recording
12
Pramod Kumar / Geekslutz Forum
13
Marrone / So Much Gear, So Little Time
1
Christof / So Much Gear, So Little Time
8
maim9 / Low End Theory
6

Forum Jump
Forum Jump