2. speakers
  3. 170928-164950

Unknown High Frequency Distortion, Recording or Speaker?

I just upgraded to Audioengine's HD6 power speaker, from the much smaller A2+. My expectation was that since the drivers are bigger and not only with far more power, but dual amps, that it would produce better mid-range and have more detailed treble. In many ways it has...but I am noticeing a weird high frequency grain-like distortion.  Like something is vibrating at a high frequency, smearing the details. Thus far, I have only heard it on two songs that I test with:

Billy Joel's "New York State of Mind."  In this song, the piano is fine, but when he sings, it's as if he is singing through an old paper cone and the paper is vibrating, causing a grainy sound to his voice.

Journey's "Faithfully" the piano distorts in the high freqncy range, as though it was recorded beyond the 0 db range and distorting, but when Steve sings...it's fine. *shrug.*

But here's the kicker.  When I run sine waves, no issue. It will start from 20hz and cycle all the way up to 20Khz with zero distorition.

Also, the A2+ did not have these issues and the HD6 is using the exact same cables and power back end. The only thing that has changed, other than the speaker itself, are the stands.  The A2+ was on the desk with their rubber stands.  The HD6 are on metal Sanus 30" speaker stands and on spikes.

So, the question is...is there something in my system causing the distortion or is it just the recording and I never noticed because I didn't have as high a resolving speaker?

guakus
guakus's avatar
guakus OP
352 posts
 

@imhififan 

I downloaded REW Room EQ Wizard.  I don't have a good microphone, especially not one with reach once plugged into the headphone jack.

However, I did run the Tone Generator.  I isolated the Left speaker, cranked the volume and ran through the tones.  I could NOT get the speaker to distort.  At all. it very much could produce any tone at damaging levels of volume with zero distortion that I was hearing.

This is why I am confused.  Is it that the speaker is so high tuned that it picks up distortion within the recording and play it?  Does that happen?  The passive speaker just receives whatever signal the powered speaker sends it and I am unable to perceive distortion from that speaker regardless of what is playing.

 

guakus's avatar
guakus OP
352 posts
 

@noromance 

*sigh* I would return them...but...I will never find these again in Cherry Wood, especially not for the price new. I lucked into these.  The guy selling them on eBay was selling at nearly 1/2 off retail because the external box was damaged.  It had a gaping hole almost dead-center.  He didn't bother to open to check the status of the speakers and just assumed they were damaged.

That hole went right between the speakers.  They were 100% untouched, undamaged. I am going to keep them, even if I have to replace the tweeter myself :)

guakus's avatar
guakus OP
352 posts
 

FINAL UPDATE:

I found out the problem and it is solved.  So for internet searching posterity, here was the problem and here is how it was fixed:

Problem:
The tweeter did not have a foam surround that is meant to cushion the tweeter where it screws into the chassis. So when complex musical energy enters the tweeter it would vibrate, which caused distortion.

Solution:
I ordered a new tweeter from Audioengine.  That new tweeter had a nice, fat, foam surround.  It installed easily and no more treble distortion! :D

So, in the end, the issue was the tweeter. Looking at the old tweeter, it looks like someone ripped the foam surround off, leaving the sticky residue and bits of foam and simply connected the tweeter anyway. So, it was also a manufacturing error.

 

imhififan's avatar
imhififan
2,231 posts
 

Glad you have it resolved 👍

More to discover