Sound issue: Atom Uniti + Scansonic MB2.5

Posted by: Gaetanop on 29 August 2018

Hello everybody,

I'm experiencing a persistent issue with my brand new installation (Uniti Atom + Naim cable + Scansonic MB2.5). As I said in a previous post (that is now closed) the sound gets "deaf" or "muted" at times. I need to push the volume up to "free" the sound until it gets "deaf" again.

My dealer extensively tested the Atom on a pair of 30k loudspeakers and could not reproduce the issue. He's lost and doesn't understand what is happening... Since the beginning, he can't believe this is a loudspeaker issue. Honestly, I'm getting nervous. I sent him the following recordings, made with an iPhone, but you can hear what I mean:

What do you think? Have you ever heard that? 

Gaetano

Posted on: 29 August 2018 by Richard Dane

On the basis of your post, the fact that the dealer has extensively tested the Atom and found no issue,  and after listening to the samples, it sounds as though there may well be some issue with the speakers.  Ribbon tweeters are notoriously fragile - they can be damaged just with excess air pressure - but it may also be something wrong with the crossover. Has your dealer checked over the speakers?

Posted on: 29 August 2018 by Gaetanop

Thanks Richard, he is in contact with the Scansonic representative in Belgium. What is a "crossover"? 

Considering the fact that the loudspeakers are 7-month old, should I ask a full replacement of both or can I accept a reparation? 

Posted on: 29 August 2018 by Richard Dane

The crossover is the electronic network inside the speaker that splits the incoming full range signal from the amplifier (via the speaker cables) into high, mid and low frequency bands that are appropriate for the individual drive units in the speaker. 

If the speakers are suspected to be at fault, then after 7 months, assuming the speakers are still within their warranty, then a repair is likely appropriate.  Of course, what happens will ultimately be down to your dealer (your warranty is through them) and what they are able to agree with the manufacturer or distributor.

Posted on: 30 August 2018 by Gaetanop

Richard, another question: you mention "excess air pressure". The speaker is in front of a window exposed to sun: could it be a possible reason? The possible heat?

Posted on: 30 August 2018 by Richard Dane

I'm no expert on ribbons, but they are so fine I'd imagine that changes in temperature could possibly have an effect.  I used to have a pair of Magnepan MG2.5Rs with ribbon units down the side.  You had to be so very careful with them.  They came with magnetic shields that you would fit over the ribbon strip recesses to protect them when moving or for periods when not in use. I treated them with kid gloves but even that didn't save one that rippled and needed expensive replacement.  I have no idea what caused it but I did wonder if it could possibly have been from standing in the sun during the day.