Interspace PCBB3 Hum Eliminator/Converter

[amirm]

This is a review and detailed measurements of the Interspace/Hive PCBB3 3.5mm unbalanced to XLR balanced converter/"hum eliminator." It was kindly drop shipped to me. This model is superseded by PCBB4 which costs US $151.

I was impressed by the very nice feel of the silicone cable bringing out the 3.5mm jack, ready to plug into a computer in live scenarios. Usually we see RCA jacks. There are options to lower level (pad), convert to mono and lift ground.

Interspace PCBB3 Converter Measurements
I start with my usual 1 kHz tone at 2 Volts:

The unit is passive which I assume it means it has a transformer. As such, the worst performance is at lower frequencies, not 1 kHz:

It saturates at just 0.15 volt and logarithmically gets worse as frequencies get lower. But need not be this bad as we see from measurements of the Jensen ISO-MAX CI-1RR competitor:

I couldn't even run the PCBB3 at 20 Hz due to its distortion going through the roof:

Frequency response is uneven as well:

Crosstalk is good enough:

Conclusions
Yes, we expect such "solution boxes" to provide adequate performance but it can't be so bad that it hurts the eye! The company should at least document the specs so you know what you are buying.

Our focus is high performance and as such, I can't recommend the Interspace PCBB3. Suggest spending a few more dollars to get the Jensen and its higher end competitors.
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As always, questions, comments, recommendations, etc. are welcome.

Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/

 

[Bogda]

So what is the real life use case of this device?
This is "solution" to what? If you want to connect cheap MP3 player to a high end balanced amplifier?

 

[JSmith]

So what is the real life use case of this device?

Reduce hum... maximise distortion and FR change.

Thanks for the testing though @amirm.


JSmith

 

[MMJ]

So what is the real life use case of this device?
This is "solution" to what? If you want to connect cheap MP3 player to a high end balanced amplifier?

We would use these kind of devices in live sound, if you want to plug in a phone to a PA to play music and such.

 

[MMJ]

I would not be the marketing guy at Interspace right now!

Gogettem, Amir!

 

[TheWalkman]

This gadget is so bad, the review should be posted on the Snake Oil thread instead of here.

 

[Redman43]

I wonder why people that don't even know USE CASE OF THIS are feeling the need to chime in with their opinions....?
This is used in cases where sound quality is NOT THAT IMPORTANT. Like connecting a smartphone to a PA system and not having everyone in room loose their hearing and it does exactly that just fine.
Last I checked PA and live performances were not what I would call "state of the art HIFI".

 

[daniboun]

Thanks Amir for the review

For products designed in the UK, it’s pretty mediocre—or even bad... take a look at their website anyway....

See attached file for full spec BTW

https://www.interspaceind.com/about/

 

[TheWalkman]

I wonder why people that don't even know USE CASE OF THIS are feeling the need to chime in with their opinions....?
This is used in cases where sound quality is NOT THAT IMPORTANT. Like connecting a smartphone to a PA system and not having everyone in room loose their hearing and it does exactly that just fine.
Last I checked PA and live performances were not what I would call "state of the art HIFI".

So you’d happily spend $151 to eliminate hum and replace it with a bunch of distortion?

Why not save $20 and get something that does the job properly?

https://www.audiosciencereview.com/...ax-ci-1rr-review-isolation-transformer.24104/

Instead, this review is a USE CASE FOR SOLVING A PROBLEM AND NOT WASTING MONEY ON A PIECE OF JUNK.

 

[Mnyb]

The cost for the unit is substantial and even if fidelity is not important it's not that unimportant it's very low hanging fruit to build a better device and charge this price

 

[sikamikaniko]

So you’d happily spend $151 to eliminate hum and replace it with a bunch of distortion?

Why not save $20 and get something that does the job properly?

https://www.audiosciencereview.com/...ax-ci-1rr-review-isolation-transformer.24104/

Instead, this review is a USE CASE FOR SOLVING A PROBLEM AND NOT WASTING MONEY ON A PIECE OF JUNK.

Maybe because it's mono and you'll need two for stereo, plus the output is still unbalanced.

 

[Roland68]

This is a review and detailed measurements of the Interspace/Hive PCBB3 3.5mm unbalanced to XLR balanced converter/"hum eliminator." It was kindly drop shipped to me. This model is superseded by PCBB4 which costs US $151.
View attachment 555969
I was impressed by the very nice feel of the silicone cable bringing out the 3.5mm jack, ready to plug into a computer in live scenarios. Usually we see RCA jacks. There are options to lower level (pad), convert to mono and lift ground.

Interspace PCBB3 Converter Measurements
I start with my usual 1 kHz tone at 2 Volts:
View attachment 555970
The unit is passive which I assume it means it has a transformer. As such, the worst performance is at lower frequencies, not 1 kHz:
View attachment 555971

It saturates at just 0.15 volt and logarithmically gets worse as frequencies get lower. But need not be this bad as we see from measurements of the Jensen ISO-MAX CI-1RR competitor:

I couldn't even run the PCBB3 at 20 Hz due to its distortion going through the roof:

View attachment 555975

Frequency response is uneven as well:
View attachment 555974

Crosstalk is good enough:
View attachment 555976

Conclusions
Yes, we expect such "solution boxes" to provide adequate performance but it can't be so bad that it hurts the eye! The company should at least document the specs so you know what you are buying.

Our focus is high performance and as such, I can't recommend the Interspace PCBB3. Suggest spending a few more dollars to get the Jensen and its higher end competitors.
-----------
As always, questions, comments, recommendations, etc. are welcome.

Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/

I’d find it really interesting to see a test of one of those cheap AliExpress DRV134 dual-channel unbalanced-to-balanced board modules for comparison. It costs less than €10 including shipping, and I’ve had good experiences with it so far.

 

[Karmacoma]

I really wonder about the genesis and developement process of such products.
Is it that hard to make a performing device of this type?

 

[Mnyb]

Somebody made a working design decades ago and no one bothered to revisit ? suppose its due to redesign if some component goes out of production .

If you truly want galvanic separation you need optocouplers or transformers ,good transformers will cost you ?

Product idea !! input ---ADC --optocoupler--DAC---output you could even have a separate isolated power supply to each side ?

 

[Redman43]

I really wonder about the genesis and developement process of such products.
Is it that hard to make a performing device of this type?

No it's not hard. But WHY would they spend more money on it?
If you want a simple car just to drive your kids to school and groceries home would you buy a 1.5 million dollars one of a kind vintage Ferrari then ?
A cheap Korean would do just fine for both purposes.
This is a cheap Korean. Why is that so hard to understand?

 

[Steve Dallas]

I really wonder about the genesis and developement process of such products.
Is it that hard to make a performing device of this type?

Good products do exist, but they are pricey:

J+4 - Radial Engineering

The Radial J+4 is a -10dB to +4dB stereo preamp that lets you boost a low output unbalanced signal and interface it with a balanced professional audio system.

www.radialeng.com

 

[DearSX]

Hmmmm

 

[Rja4000]

Thanks for review !

Doesn't compare well with Jensen...

 

[pma]

Looks like transformers inside, small ones, thus the LF distortion. I would have hoped for ASR not to deal with such s..t products.

 

[Power Pop 23]

I wasn't expecting such a range of measured performance between the Interspace PCCB3 and the Jensen ISO-Max CI 1RR.

It makes me wonder how 'well' my Rolls 'HE18' would measure.....