Interspace PCBB3 Hum Eliminator/Converter

[johnnyx]

I worked for a company that made 8-channel transformer isolators for stage and studio.

The transformers had an additional feedback winding.

The input stages were instrumentation style balanced opamp sections that incorporated the feedback winding to linearise the transformer's response.

 

[LuckyNat]

All of that is fine if the company provided proper specifications so people know what they are buying. Otherwise the assumption is that the device is fully transparent.

"So people know what they are buying" .. Which people ? And where are they buying it from?

Interspace quite clearly sell cueing systems and timer systems for presentations ..

Interspace sell their products through dealers who again clearly sell professional a/v products for conferences and live events .

Anyone buying these products know what they are buying and they know what they need.

The specs provided are quite adequate IMO for the use case that everyone is buying it from .

 

[LuckyNat]

Yep, if a powered unit is an option, it is much better, even with transformers.

 

[M.C. Logan]

You have a ground loop and have tried everything but it won't go away. These things are a solution for that especially since they convert unbalanced to balanced.

Only problem being that very few products have more than one (if indeed any) balanced inputs, outside of professional gear.

 

[drumphil]

Only problem being that very few products have more than one (if indeed any) balanced inputs, outside of professional gear.

That's a problem?

¯\_(ツ)_/¯

 

[LuckyNat]

If you're trying to solve ground loops with this bit of kit .. when all your home hifi is unbalanced .. err yes that would be a problem.

A daft problem, maybe an ironic one .. but a problem.

 

[drumphil]

If you're trying to solve ground loops with this bit of kit .. when all your home hifi is unbalanced .. err yes that would be a problem.

A daft problem, maybe an ironic one .. but a problem.

It can even do that with a basic adapter cable.

Regardless, that seems more like an example of a problem with using the wrong piece of gear, rather than a problem with the piece of gear itself.

 

[LuckyNat]

It can even do that with a basic adapter cable.

Regardless, that seems more like an example of a problem with using the wrong piece of gear, rather than a problem with the piece of gear itself.

I agree ... but some people see a piece of gear being reviewed, think "I don't see how that is useful *for me* " and see that as a "problem" lol.

Essentially what is meant is "Its a problem that I have no use case for this [after having read the whole review and thread .. ] " .

 

[LuckyNat]

It can even do that with a basic adapter cable.

Regardless, that seems more like an example of a problem with using the wrong piece of gear, rather than a problem with the piece of gear itself.

I would argue that in many cases an adapter cable (no transformers) may be a solution to ground loops on its own . Often it comes down to how circuit ground is wired up in each equipment.

 

[drumphil]

I would argue that in many cases an adapter cable (no transformers) may be a solution to ground loops on its own . Often it comes down to how circuit ground is wired up in each equipment.

Lifting the shield is frequently enough with balanced audio systems, and there are better and worse ways of connecting an unbalanced system to a balanced one, but in the world of completely unbalanced, it can be more problematic ( to put it mildly!) not having a ground connection, which is the only non signal connection you really have to play with!

Not much you can do in a completely unbalanced system with ground loop noise, (that doesn't involve silly things like disconnection the safety ground from the power cable) short of galvanic isolation.

 

[LuckyNat]

It is often tricky, yes. There are some wiring schemes though that can help .. I cant remember what they are without searching

 

[drumphil]

It is often tricky, yes. There are some wiring schemes though that can help .. I cant remember what they are without searching

Covered comprehensively in the Rane Notes - from earlier in this thread: Post # 60

Interspace PCBB3 Hum Eliminator/Converter

I really wonder about the genesis and developement process of such products. Is it that hard to make a performing device of this type? Go to Jensen transformer website (radial engineering) and copy one of there designs that have been used for 50 years. Good audio transformers are not cheap and...

www.audiosciencereview.com