Neumann KH120 II Monitor Review

[bitels]

Eve sc207 which have same fr range as kh120II don't produce this port noise too. I quess, it is defined by port construction.



This noise is produced in 50-65 Hz range, so in operating frequency region of kh120.

 

[ernestcarl]

I've switched positions with hs8, and kh120 produce same port noise.

From what you say, Mk II is improvement, indeed.

I understand size difference, but hoped to find no flaws in kh120 II.

Years ago when I was comparing the KH120 to the Sceptre S8, I remarked about dissatisfaction I had of the former due to its bass performance given both were bought at nearly about the same price range at the time. I know that the Sceptres, of course, are much larger speakers and yet had other flaws (e.g. FR unevenness due to horn diffraction) -- something has to give either way. Well, there's always trade-offs given the budget and speaker design/engineering choices.

 

[Pearljam5000]

I wonder if this would happen also on KH150

 

[ernestcarl]

I wonder if this would happen also on KH150

There's likely going to be chuffing after a certain point. You might avoid it by sealing the speaker ports or by applying a HPF. The only question is at what level and if it's acceptable to the user.

 

[dfuller]

Hoffman's iron law strikes again. SPL, small size, bass extension. Pick two at the expensive of the third.

 

[Bambo]

Here is link to video highlighting this problem.

Can you send us this reference here? I wanted to test my KH120 II. Maybe someone else will be interested too

 

[bitels]

Hey,

I can not find loop from youtube short I added, it was random one from splice, but here are two other ones, that highlight problem:

They present port noise even better at lower volume.

kh 120 test - Google Drive

drive.google.com

Also this sine wave:

It starts form 70 db, at 75 it is bad.

First 8 seconds, and last 20 seconds of song when bass hits.

 

[Bambo]

Д

Hey,

I can not find loop from youtube short I added, it was random one from splice, but here are two other ones, that highlight problem:

They present port noise even better at lower volume.

kh 120 test - Google Drive

drive.google.com

Also this sine wave:

It starts form 70 db, at 75 it is bad.

First 8 seconds, and last 20 seconds of song when bass hits.

Thank you! I'll test it in a few days

 

[Pearljam5000]

I used this track to test the bass on my KH 120
It could handle it.. To a certain degree lol

 

[bitels]

Dear Patryk,

thanks for providing the audiofiles for further analyses.

I got feedback from our productmanagement team and also from development department.

Speakers with ports generally have a strong flow in the channels at the tuning frequency. As the level increases, this will eventually become audible, no matter how much effort is put into the port geometry. In principle, a closed system with a larger driver has no port noise. If the ports are at the rear, as with the Yamaha monitor, they are not so audible from the front, but they have other disadvantages.
At some point, every loudspeaker comes to an end and parasitic effects become perceptible.

- Yamaha has a larger woofer with a larger cabinet volume and a different tuning frequency of the BR system
- BR port on Yamaha is at the rear, so port noise is less audible at the front

It is highly unlikely that the speakers are defective, as they are extensively checked for cabinet resonances during the final inspection. Probably simply a limitation of a compact 5.25” loudspeaker.

Info from Neumann, I am not shure if they checked provided audio or not.


Is there a chance someone with KH 120 II will check on their pair.


Audio files:

kh 120 test - Google Drive

drive.google.com

 

[Pearljam5000]

Info from Neumann, I am not shure if they checked provided audio or not.


Is there a chance someone with KH 120 II will check on their pair.


Audio files:

kh 120 test - Google Drive

drive.google.com

I guess you'll need a sub or just upgrade to KH 150

 

[thewas]

Info from Neumann, I am not shure if they checked provided audio or not.


Is there a chance someone with KH 120 II will check on their pair.


Audio files:

kh 120 test - Google Drive

drive.google.com

I can imagine the shock for some fan to see the absolutely correct answer from the company itself that there is nothing perfect in this universe and that everything is a compromise.

 

[holdingpants01]

BTW how do you estimate the playback volume? Are you using an app to measure it?

 

[bitels]

BTW how do you estimate the playback volume? Are you using an app to measure it?

I use C weighted spl meter.

 

[Pearljam5000]

What's the minimum woofer size to avoid this kind of problem
6.5 or 8 inches?

 

[staticV3]

What's the minimum woofer size to avoid this kind of problem
6.5 or 8 inches?

Port chuffing can occur regardless of woofer size.

As always, it's the implementation that matters, not the raw components.

 

[HQY]

just made a decision and placed an order for a pair of 310a monitors to replace 120II. Also an order was placed with Sound Anchors for a pair of stands for the 310a. Will pair them with dual 750 subs to get a 2.2 DSP speaker system. The 120IIs will be sold although they are pretty good monitors.

 

[Brent71]

I'm late to the party, but that step response is not good!

This is good step response:

 

[RobL]

What about the KH120 ii step response do you dislike?
For a 2-way, it looks pretty much like the right angle triangle ideal, imo.

Edit: I’ve added what an “ideal” step response looks like….kinda familiar, no?

 

[Vergiliusma]

What's the minimum woofer size to avoid this kind of problem
6.5 or 8 inches?

Per Richard Small its Vd(Sd x Xmax)--the higher it is, the more port area is needed for a given tuning.

I'm not sure why some are concerned about this though with this small loudspeaker, which should be used in the application for which it was designed: a very linear studio monitor used at moderate volumes and/or high-passed with subs.