Weird flanging/Leslie effect


Hi all (my first post)!

I’ve been trying out HAs for a few months now. I tried out Phonak Virto B90 Phonak Virto™ B and, while, when I set the position of them just right, the sound was stunningly good, the shape of my ear canals are such that after 4 shells that only sounded right if I pulled the HA a little bit out of the canal, we decided to go with RIC instead.

I’m currently testing Signia Pure 10 Nx5, have an appointment on Monday to test Signia Pure 312 Nx7 and will test Phonak Audeo 312 M90 as soon as they are available at my audiologist (in a couple of weeks or so).

But I wanted to ask about some weird, for a lack of better word, Leslie speaker effect ( that I’m experiencing with the Pure 10 Nx5. The frequency if the effect is about 5-6Hz, regardless of the pitch of the tone

I am an amateur gutarist and the sound of the guitar through these HAs is simply horrendous. The test music that I use (Dave Grusin - Born Again, The Notting Hillbillies - Missing…Presumed Having a Good Time) is unlistenable.

My audiologist has programmed them so that I can switch on the music program manually and, while it’s a bit better, the effect is still there and is annoying. It’s also not a solution, because all the voices also have this effect in the universal program.

Has anyone any idea what is happening and is this artefact confined to this model, to RIC HAs, or is this a particular problem with Signia? The Phonaks that I’ve tested amplified the music perfectly - the result was the same as when I processed the test music through Audacity, with the equaliser set to inverse of my ADG.



Just a wild guess here. The flanging/warbling may be due to the frequency shift technique in feedback control. it doesn’t hurt to turn off the feedback manager to see if that helps. If not, you can always turn it back on again.


+1 for the description. :slight_smile: My guess is the HA is fighting feedback.


I am not familiar with the product you are talking about, but most modern instruments have the ability to set the feedback manager into a Static mode as opposed to adaptive. Often times setting it to static mode eliminates the ghost signal you experience with high notes in music. Ask your tech if there is such a thing, or if they have an actual music setting or algorithm that can be employed.

Good luck.


Thanks for replies. Yes, the frequency shift theory makes perfect sense. I will mention it on Monday and have the tech try it out. The test should be very simple.(and I’ll report back).