harshness

[Professor smith]

where does the harshness come from in a speaker? what frequency range causes this?

[AllenB]

I am not so sure harshness covers just one phenomena. I could generalise and suggest you look at diffraction, or fix sibilance issues. I believe that sibilance issues can be influenced by the response of a wide range of frequencies throughout the midrange and treble. Does your room make things worse?

[Professor smith]

yes the room does change the harshness. One room which is more lively but also better dimensionally, gives less harshness. Another room which is bad dimensionally but also much more damped and dead, gives me more harshness. Everything else remaining constant, what does this indicate?

[strawberry]

I think what you hear is the harsh peak near the end of the audible range of the driver. You can combat the peak by putting a zobel circuit in parallel with the driver. For a woofer it's typically 8-10 ohm (10 watt) and 14-22 uF 63-100v.

[AllenB]

Originally Posted by Professor smith

yes the room does change the harshness. One room which is more lively but also better dimensionally, gives less harshness. Another room which is bad dimensionally but also much more damped and dead, gives me more harshness. Everything else remaining constant, what does this indicate?

Not enough to suggest the speaker is free of harshness on its own. Regardless though, room placement might improve lower midrange cancellations whose frequencies fundamentally support many musical sources. Maybe treble reflections are an issue. Maybe the speaker has poor off-axis performance.

Originally Posted by strawberry

I think what you hear is the harsh peak near the end of the audible range of the driver. You can combat the peak by putting a zobel circuit in parallel with the driver. For a woofer it's typically 8-10 ohm (10 watt) and 14-22 uF 63-100v.

I wouldn't suggest this in this way. Zobel compensation is neither a requirement, nor a good idea as a small tweak with an existing non-compensated crossover.

[Soundminded]

In my experience the harshness usually comes from a peak in the range of 4 to 5 khz especially if output in that region is even slightly greater than in the region just below it. This translates into a brightness, hardness especially in string instruments (violins in particular), tendency of pianos to sound like harpsicords. A dip at that frequency range translates into a dullness or remoteness. FR in that range is extremely critical. This may be done deliberatly because to untrained ears it is especially attention getting in rapid fire A/B comparisons in dealer showrooms but experienced listeners know it can quickly become very tiresome when listening at home. The best cure is a graphic equalizer. This allows you to find the region where the problem is and correct it. The sharper and narrower the peaks, the more bands you will need so that you can selectively adjust for only those frequencies where the problem is. If your religion precludes using an equalizer, learn to live with it or throw a heavy winter coat over your speakers. That should fix it too.

[mdocod]

Amplification quality can have an enormous amount to do with it in my experience. If you are stacking up a pile of odd ordered harmonics, They are apt to culminate in the mid-high frequency range and make the system sound harsh and/or fatiguing (pick your adjective).

If this is not the case, then I agree with the direction others have suggested. Probably dealing with peaking issues where wavelength size is close to that of the diameter of a driver or smaller but before significant cone breakup cancels out the frequency. Best solution IMO is to try to get x-over points low enough to get these peaks at least 6-12dB below the primary listening level. Some drivers tame out these peaks better than others. Also, as I understand, these "phase plugs" in the center of many modern designs are, I believe, intended to help diffuse the on-axis peaks, with varying degrees of success from driver to driver I also like the effects of a zobel network in nearly ever sim attempt I have made, so considering how cheap that is to try I say it's a no brainer.

Eric

[gedlee]

Originally Posted by Professor smith

where does the harshness come from in a speaker? what frequency range causes this?

Until there is a common deffinition - in objective terms - you cannot define where it comes from. I don't know of any accepted deffinition. I think that we would all agree that it a higher frequency effect, but beyond that I don;t think that there is much consistancy.

[Professor smith]

Originally Posted by gedlee

Until there is a common deffinition - in objective terms - you cannot define where it comes from. I don't know of any accepted deffinition. I think that we would all agree that it a higher frequency effect, but beyond that I don;t think that there is much consistancy.

As a science person I agree we need to be objective but we are talking about sound qualities here. How can we expect consistency? What you say, applies to every aspect of sound quality.

[bobodioulasso]

I experience harshness from my Audax hm170Z18 (c/o 2200hz) when it's rising response is not properly equalized down.
That's very noticable when listening to piano. It sounds like a resonance around 1000/1500hz.