You are here

active balanced/unbalanced converters

Customising, building or repairing your own gear? Need help with acoustic treatment or soundproofing? Ask away…

Moderator: Moderators

active balanced/unbalanced converters

Postby Urmy14 » Mon Mar 01, 2021 3:29 am

Hi, just joined the forum & subscribed to SOS Digital tonight, so I’m new here - please forgive if this question has already been dealt with. I looked but didn’t see a thread.

Ok, i’ve just read ‘Patchbays For The Modern Studio’ and I’n left with a question about a statement at the bottom of the article. It said that “ active balanced/unbalanced converters” are particularly good for use with pedals and instruments.

I’m looking for the correct rack unit to balance all the unbalanced signal coming from my synths and guitar pedals before patching them into the patchbay and ultimately my Apollo.

Hoping to find an 8 channel rack unit that will accel at this. Been looking at the ART T8 bit was worried about loss.

Any thoughts/suggestions most welcome! THANKS!
Urmy14
Posts: 3
Joined: Mon Mar 01, 2021 2:43 am

Re: active balanced/unbalanced converters

Postby The Elf » Mon Mar 01, 2021 10:33 am

Unless you are trying to solve a known problem I wouldn't do this. I would simply plug the synths into the line inputs of an audio interface.
User avatar
The Elf
Jedi Poster
Posts: 16570
Joined: Tue Aug 14, 2001 12:00 am
Location: Sheffield, UK
An Eagle for an Emperor, A Kestrel for a Knave.

Re: active balanced/unbalanced converters

Postby Hugh Robjohns » Mon Mar 01, 2021 11:54 am

There isn't a one-size fits all solution to this one, and it's better to deal with individual sources and destinations to resolve specific problems.

Most of the time keyboards and effects pedals can be plugged through a patch-bay in their natural unbalanced state without problems. If you do come across an instrument that creates ground-loop issues then you can deal with that using an isolating transformer or a customised pseudo-balanced cable.

If you need something to alter signal levels to and from pedals, then something like the ART Cleanbox Pro can be helpful -- and again, you could make it a patch-able facility on the jackfield.

As for the T8, there's no real loss through the unit, although you need to be a little careful with signal levels to avoid saturating the transformers at the low end.
User avatar
Hugh Robjohns
Moderator
Posts: 30689
Joined: Fri Jul 25, 2003 12:00 am
Location: Worcestershire, UK
Technical Editor, Sound On Sound
In my world, things get less strange when I read the manual... 

Re: active balanced/unbalanced converters

Postby Urmy14 » Mon Mar 01, 2021 2:43 pm

Thank you so much for the replies!

I definitely want to integrate patchbay into my workflow, so I’m not constantly re-plugging things every time I want to add a new unit to the signal flow. If you’re saying that I can go directly from the patchbay into my audio interfaces (Apollo X8P), then that’s great!

I was under the impression that a direct box was preferred to get all of the unbalanced signals to be balanced before hitting the Apollo.

I see ART has the PDB4 rack DI, and it is affordable, but if it’s unnecessary then that’s great I can just save the money! Is this correct? Or is the DI the preferred way to go...?

Thanks again everyone!
Urmy14
Posts: 3
Joined: Mon Mar 01, 2021 2:43 am

Re: active balanced/unbalanced converters

Postby The Elf » Mon Mar 01, 2021 3:38 pm

You don't need a DI. All you need is to plug synths, which are close to line level outputs, into line inputs, so on your patchbay normalise your synth outputs to your interface's line inputs. Use a balanced connection, if your synth provides it, but beyond that - wire up and relax!
User avatar
The Elf
Jedi Poster
Posts: 16570
Joined: Tue Aug 14, 2001 12:00 am
Location: Sheffield, UK
An Eagle for an Emperor, A Kestrel for a Knave.

Re: active balanced/unbalanced converters

Postby Hugh Robjohns » Mon Mar 01, 2021 4:22 pm

Urmy14 wrote:If you’re saying that I can go directly from the patchbay into my audio interfaces (Apollo X8P), then that’s great!

Yes, of course you can. It's no different to plugging directly between the source and the interface... the patch bay just provides an accessible break point in the connection.

I was under the impression that a direct box was preferred to get all of the unbalanced signals to be balanced before hitting the Apollo.

A Di box lowers the instrument signal to balanced mic level, so you'd have to connect via a mic preamp in your interface. That's fine if it's what you want, and it may be necessary if you find you need extra gain for some sources, but it's an unnecessary expense for most situations. In general, keyboards can be connected directly to line inputs.

Or is the DI the preferred way to go...?

As I said earlier, there is no one-size fits all solution. The optimal connection format depends on the gear and the circumstances. A DI box normally provides an earth lift to break ground-loops, which can be handy in some circumstances, and by connecting via a mic preamp you usually have a lot of gain available should the source be particularly low level.

But with an increasing number of sources these days having double-insulated (class-2) mains power supplies, ground loops aren't an issue, and a direct connection is often the best way of ensuring the source is correctly grounded.
User avatar
Hugh Robjohns
Moderator
Posts: 30689
Joined: Fri Jul 25, 2003 12:00 am
Location: Worcestershire, UK
Technical Editor, Sound On Sound
In my world, things get less strange when I read the manual... 

Re: active balanced/unbalanced converters

Postby Urmy14 » Tue Mar 02, 2021 4:02 am

Thank you for the feedback!
Urmy14
Posts: 3
Joined: Mon Mar 01, 2021 2:43 am

Re: active balanced/unbalanced converters

Postby dlsmusic » Mon Mar 08, 2021 3:34 am

I just integrated a patch bay into my studio and have a mix of balanced and unbalanced instruments going in with no issues. You should be fine. I'm using the Samson patch bay.
dlsmusic
New here
Posts: 6
Joined: Thu Oct 27, 2011 12:00 am
Location: Salem, New Hampshire USA