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Neumann KH420 Review (Studio Monitor)

Rate this speaker:

  • 1. Poor (headless panther)

    Votes: 2 0.4%
  • 2. Not terrible (postman panther)

    Votes: 3 0.6%
  • 3. Fine (happy panther)

    Votes: 29 5.6%
  • 4. Great (golfing panther)

    Votes: 488 93.5%

  • Total voters
    522

sibi1865

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It doesn't appear that Neumann MA-1 supports the 420 at all? It says it supports monitors the 750 DSP supports, and the 420 is not listed there.
Although it is an SPL mismatch, you can hook up the 420 to the 750 DSP and use the MA-1 for room correction.
 

Eetu

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AutoEQ could flatten it but below 100 hz (or more) you will need to correct in room in any case.

For this speaker, anechoic EQ is not useful.
Of course, I only meant in the context of the post-EQ score. I noticed AutoEQ doesn't correct other <100Hz issues either (KEF 'bass shelving' for example) so I guess it's apples-to-apples. Thank you for your awesome site!

And I agree, a great speaker as it is.
 

Robbo99999

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Come on, I need to express this.

To my knowledge Pearljam never has presented himself as an highly skilled expert but rather as an enthousiaste.

I think anyone should respect him for its participation here, which I understand also more as a « student » or « moderator » or « interviewer » role, asking many questions, making assumptions in the name of all us technical ignorant enthousiastes, so that the real knowledgeable persons/experts can answer, explain, correct, teach and share their knowledge.

I also think that this is a real asset to the different threads and he never gets upset despite some bashing happening from time to time.

I would thank him for that.

I don’t think to have understood that this site would have been reserved to highly skilled ingenieurs only.

Thank you for understanding my irritation.
I agree that there is nothing wrong with the questions / discussions Pearljam has been having today....sometimes as a person on here you would make assumptions or conclusions based on your own reasoning from the knowledge you do have, and then sometimes those assumptions & conclusions can be wrong - at which point it's down to the experts in that field to correct them without being too negative (eg facepalming, lol!). So he's not at fault.
 

Tangband

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The topic is long researched like since the 60s by the BBC, there are enough papers if you are interested.
As said stiffness is not enough, very important is the damping. Have a metal structure with no damping and it can ring like a bell as the material damping of metal is very low.
There are even recordings where you can see for example that a thinner 16mm MDF with damping gives a much lower coloration than a thicker 22 mm one without:
https://www.hifi-selbstbau.de/bauvorschl-mainmenu-36/2-wege-lautsprecher-mainmenu-75/416-duo-dxt
I have read all the BBC dokuments and also the other documents you refer to. What Im meaning is that the perceived ability to understand the music, becomes better if the resonanses are pushed up in frequency - making the cabinett stiffer.
The music will sound better.

Music is ordered frequencies in the time domain , which is very different from sine-sweeps or static test tones.
A low Q resonanse at 200 Hz is much worse for real music, than a high Q resonanse at 800 Hz .
The low Q resonanse will release its energy out of phase with the music, and the energy will be more delayed in time, than the high Q resonance at 800 Hz .
 
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Tangband

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I completely agree with you. I’ve always tried to avoid « all in one » products, be it hifi or coffee machines, just for that reason. Simply because if one part fails, everything fails. And this seems to be even more important nowadays, because things, especially electronic components, seem to last a lot shorter than they used to do. In our current « throw-away-society ». What a drag. The same way I stay rigorously away from subs that are controlled (solely) by an app, because you can be pretty sure that app support will fail in the near future, way before the sub is end of life.

But what probably could be said for the benefit of this and some other Neumann products is that, since they are all analogue, they are servicable right up to the end. Which means a very extensive life-cycle.
You can have an active loudspeaker with the electronics outside of the cabinet:).
 
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thewas

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I have read all the BBC dokuments and also the other documents you refer to. What Im meaning is that the perceived ability to understand the music, becomes better if the resonanses are pushed up in frequency - making the cabinett stiffer.
If you have read the BBC documents, you will see their target was to reduce eigenfrequencies to take them out of the mid band where they are most audible.

The music will sound better.

Music is ordered frequencies in the time domain , which is very different from sine-sweeps or static test tones.
A low Q resonanse at 200 Hz is much worse for real music, than a high Q resonanse at 800 Hz .
Do you know of any papers that show that? Also who said that that by making something stiffer, i.e. increasing the eigenfrequencies, that the Q will change? The Q depends on the damping factor, which is as said something different and independent from the stiffness.
 

DSJR

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I have read all the BBC dokuments and also the other documents you refer to. What Im meaning is that the perceived ability to understand the music, becomes better if the resonanses are pushed up in frequency - making the cabinett stiffer.
The music will sound better.

Music is ordered frequencies in the time domain , which is very different from sine-sweeps or static test tones.
A low Q resonanse at 200 Hz is much worse for real music, than a high Q resonanse at 800 Hz .
The low Q resonanse will release its energy out of phase with the music, and the energy will be more delayed in time, than the high Q resonance at 800 Hz .
My old 'buzzy-box' Spendor BC2's have a wonderful midband even today, only losing it a little further up. The only real issue with the proper Spendor, the BC1's back then, being bass power handling and a general excess around 100Hz which I believe was more driver-cab matching as well as the port, which did come good eventually. The bass driver characteristics were seemingly better suited to a sealed box according to the Troels Gravesen - his review of a late properly finished and ported pair below -

 
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AdamG

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Thread Notice: Please bring the conversation back on topic. You may discuss these other topics in the appropriate thread. Please and thank you for your understanding and assistance.
 

TulseLuper

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this stuff might be a "high end" alternative to more "standard" MDF:


Have not seen it advertised for speakers (except for GGNKT)

I've used both Valchromat and GeoTone for speaker boxes. They're conveniently died all the way through and do not contain some of the toxic chemicals in standard MDF. Great material to work with. No idea about the acoustic properties vs. MDF, but braced properly I'm sure it's fine.
 

dfuller

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Anyway... On the topic of the KH420, it competes handily with the ATC SCM50ASL Pro, which is close to twice the price.

So, good deal I'd say.
 

Pearljam5000

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Come on, I need to express this.

To my knowledge Pearljam never has presented himself as an highly skilled expert but rather as an enthousiaste.

I think anyone should respect him for its participation here, which I understand also more as a « student » or « moderator » or « interviewer » role, asking many questions, making assumptions in the name of all us technical ignorant enthousiastes, so that the real knowledgeable persons/experts can answer, explain, correct, teach and share their knowledge.

I also think that this is a real asset to the different threads and he never gets upset despite some bashing happening from time to time.

I would thank him for that.

I don’t think to have understood that this site would have been reserved to highly skilled ingenieurs only.

Thank you for understanding my irritation.
Thanks, really appreciate it:)
 
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Frgirard

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Anyway... On the topic of the KH420, it competes handily with the ATC SCM50ASL Pro, which is close to twice the price.

So, good deal I'd say.
The weight of the both are different. The KH is a light bookshelf speakers.
 

antennaguru

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I've used both Valchromat and GeoTone for speaker boxes. They're conveniently died all the way through and do not contain some of the toxic chemicals in standard MDF. Great material to work with. No idea about the acoustic properties vs. MDF, but braced properly I'm sure it's fine.
I have used thick solid kiln dried hardwood for some of my DIY speaker project cabinets, with bisquet joinery using lots of glue and many clamps. The advantage to me is that it is easy to heavily round the corners using my router, and that after sanding I can apply a simple finish like Tung Oil as a protectant that lets the natural grain of the hardwood show thru. A second future advantage is that hardwood is a tough material that shrugs off the sort of impacts that generally crush MDF, and any nicks or gouges that do eventually develop can just be sanded down and another coat of Tung Oil finish can be applied over the re-worked hardwood.

I do use internal bracing and also line any cabinets that are going to be "sealed" with damping material (by "sealed" I mean both Acoustic Suspension and Bass Reflex designs). However, some of my more successful projects have been Open Baffle designs, so no damping material was used for those.

IME hardwood cabinets have all held up well over time, and also look really good - but do NOT have the industrial look that some prefer. The acoustic properties seem just fine.

WRT the crushed KH420 corner that was pictured, I would sand the damage down to make it smooth, brush it with two-part epoxy resin/glue, and then after the resin has cured apply some touch-up paint. If the damage was more serious and went deeper, I would also apply a layer of raw carbon fiber or fiberglass cloth on top of the wet two-part epoxy resin/glue, and then apply more epoxy resin/glue on top of the cloth - then once cured a final sanding and touch-up paint. I have some rough handled KRK passive monitor speakers that I repaired this way and the repair is holding up very well, although the touch-up paint color was not easy to match.
 

pseudoid

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You are right that a stiffer cabinet pushes the resonanses uppwards in frequency but you are wrong about that this fact is more problematic. Its exactly the opposite - the loudspeaker cabinet will sound better , the higher in freq the resonanses are .
I have been listening togethet with a number of people ( other DIY:er ) and all agrees on this .
Releasing delayed cabinet resonanses at lower frequensies are the absolute worse you kan imagine in a cabinet, soundwise.
:cool:
I have always liked speaker 'waterfall' plots (spectral-decay times versus level/frequency).
1651690302909.png

I don't care if there are haters or if some think they are worthless, imaginary, error-prone and/or problematic.
EDIT[add]: I :)hope that is "not bit grumpy this morning"
 
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DSJR

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The weight of the both are different. The KH is a light bookshelf speakers.
The ATC drive units are seriously overbuilt and it was a selling point in my day selling and owning the brand. My original 100A bass drivers even had a sodding great 'heatsink' kind of affair over the magnet (abandoned in the SL version of the driver I remember). The Neumann almost certainly uses more contemporary driver chassis' (I know nothing of their mid dome) which won't be as heavy.

By the way, the raw carcass of my 100A's was actually rather light considering it's size and built-up bulk. I believe it was damped MDF from memory and models like mine had wool filling held by stapled netting. No idea what Neumann do to the innards of their cabs but I'm sure it's well researched...
 
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Although the KH 420 is not a match to the KH 750 DSP's SPL, they can be hooked up to the 750 to use its DSP capabilities. Is there a reason why Neumann could not produce an external box of tricks, or does the DSP have to be in-built into the monitor/sub? For those with the means, the KH 420 can be flush mounted, and the amplifiers removed and used remotely from the monitor. Very nice to see this review!
There is a lot argument in this thread about DSP or not, dac or not included in the speaker, Think about what you want to use as a source and then move on. KH420 do have a digital module available called dim 1. DSP can also be done by others then Neumann.


Dont know the quality of the D/A in it but doubt it will be the sound limiter in the setup.

For exsmple Minidsp SHD studio as source and DSP.


Then add own preference of subs. Like SVS 2000 or 4000, the tubes have high waf output and probability of them functioning in corners, adding ti waf;)


Much cheeper and probably not Worse if not better then going the «only neumann route».
 

LTig

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The ATC drive units are seriously overbuilt and it was a selling point in my day selling and owning the brand. My original 100A bass drivers even had a sodding great 'heatsink' kind of affair over the magnet (abandoned in the SL version of the driver I remember). The Neumann almost certainly uses more contemporary driver chassis' (I know nothing of their mid dome) which won't be as heavy.

By the way, the raw carcass of my 100A's was actually rather light considering it's size and built-up bulk. I believe it was damped MDF from memory and models like mine had wool filling held by stapled netting. No idea what Neumann do to the innards of their cabs but I'm sure it's well researched...
As far as I know the KH420 uses a switched power supply which (at a combined amp power of 600 W - almost twice of the ATC50SCM pro) also results in a significant loss of weight.
 
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