Yamaha NS-5000 design compromises?

The very intersting thread titled "Are they all badly designed?" got me thinking again about the Yamaha NS-5000s and all the areas of performance they seemed to take into consideration....and one big one that they did not. There's a nicely constructed cabinet to avoid box/panel resonance, fancy custom drivers attemting to reduce both cone resonance AND backwave resonance, and that tuned pipe resonator device. Lots of concentration on various resonant "gotchas", but then they do something so 70's and use a very high crossover point btw the mid and tweeter AND have a large physical separation btw the two drivers. Yamaha already went to the expense of creating totally custom drivers, so it would have been easily within the realm of design considerations and budget to craft custom faceplates to join the mid/tweet into a closely spaced assembly. I don't get the engineering choice to completely disregard this facet of performance. I know that every speaker design is a trade-off of various design goals, and that no one speaker can have each aspect be perfected, but this seems like such simple design flaw with an equally simple solution. It's not like Yamaha is some cottage industry started by a fellow DIYer who thinks they know everything they need to know and designs a speaker with the tweeter and mid separated by a foot. This is a major, multinational company with plenty of money for research and development. Another thing I don't get is that the tweeter is listed as 1.25", so what in the world is going on that they feel the need to cross the driver all way up at 4.5KHz, per Yamaha's own website specs. These are similar crossover points (4.5K rather than 6K) and driver size/spacing to the original NS-1000, which Danny at GR measured and showed how poor the verticle off-axis performance is. I don't want to get into a Danny at GR dicuss all over again here, but his measurements seem to show what I'd expect. I'd love to see the designers at Yamaha questioned about why they let this high crossover point and large spacing go into production. And I'd love to see full spin-o-rama polar plots on these too.

https://usa.yamaha.com/products/audio_visual/speaker_systems/ns-5000/index.html

https://usa.yamaha.com/products/audio_visual/speaker_systems/ns-5000/specs.html#product-tabs
 
  • Like
Reactions: 1 user
Maybe Danny provides exact measauring conditions somewhere in his videos or elsewhere, but from a quick search I couldn't find them. 5 traces with a 5-6 dB of bundling at 10 kHz indicate this is definitely 0-40 degrees measuremetnt with a 10 degree step.
1694970810256.png

To confirm, I have overlayed Troels Gravesen FR set (0-45 degrees) stretched to the same scale - there is good compiance in tweeter region, considering setup differences etc.
1694971931053.png

Overall, my experience with several pairs of NS-1000(M)s is mostly the same: while the drivers are amongst the best I have ever seen, crossover and baffle could use an improvement.
 

Attachments

  • 1694971469738.png
    1694971469738.png
    79.9 KB · Views: 63
  • Like
Reactions: 1 user
Member
Joined 2005
Paid Member
And it was designed for the high end / audiophile market.

I have a Yamaha digital piano that was released about a decade ago. One rainy day in Vancouver (there are a lot) the engineer in me went looking for the service manual.

They use totally custom ASIC for DSP and FIR for their US$3000 (mid tier) digital pianos.

Yamaha could have totally done the 21st century thing with WISA, AirPlay 2, Bluetooth 5.x, Dante, DSP, FIR, tri-amped, extendable bass section ala Kii 3 BXT, auto room EQ etc etc. powerhouse. I mean they really could have done an Apple or B&O and released a speaker with all the high tech trimmings (for better or worse) But decided against it.

I agree with Dave- they decided to do a C21 NS1000 update- a traditional 3 way classic box speaker.
 
  • Like
Reactions: 1 user
Danny at GR measured and showed how poor the verticle off-axis performance is. I don't want to get into a Danny at GR dicuss all over again here, but his measurements seem to show what I'd expect.

This isn’t unique, as these behaviours were published by Yamaha almost 50 years ago in polar and traditional response graphs.

It’s important to note the drivers Danny measured did not represent typical behaviour, and both the midrange and tweeter show an unusual defect. I state this unequivocally as someone that has tested dozens of these drivers. The ringing he shows corresponds to the exact diameter of the magnetic gap. At the rear of this gap, behind the voice, there is a foam absorber, and the midrange he measured needs to be checked to determine if this has been disturbed. The exact magnitude and frequency of the peak in the tweeter was also not typical.

I’ll show here what they should behave like.

No peak or ringing mode at 1.8kHz in the midrange:

lXvfC6c.jpg


Midrange, 0 and 45 deg:

QjstqLk.jpg

Midrange and tweeter, notice there is no ringing peak at 3kHz in the tweeter:

3REweu9.png
 
  • Like
Reactions: 1 user
And I'd love to see full spin-o-rama polar plots on these too.
-also these NS2000A:


https://usa.yamaha.com/products/audio_visual/speaker_systems/ns-2000a/index.html

I really like the Japanese market's respect with internal loss in the cabinet, they try real hard to mitigate this and will often use exotic materials like charcoal for sound absorption (or in this case a tuned damped line in-cabinet). I'd bet the little "flight-alcohol trophy bottles" for the air cavities of the tweeter and the midrange are a significant step forward in that balance of mitigating the rear reflection without increasing resting resistance significantly for those drivers.


I should note that with Yamaha high-end loudspeakers it's all about selling in Japan 1st to their audiophile market with everyone else as a "take-it-or-leave-it".
 
Last edited:
  • Like
Reactions: 1 users
both the midrange and tweeter show an unusual defect
An interesting point. I have measured and taken apart (to repair dislodged magnets) several midranges. There indeed should be no 1.8 kHz mode; also, I fired up a qucik VituixCAD sim to check midrange diffraction, and it shows no issue there.
NS-100M mid 60 mm NF no rebate baffle
NS-1000M 2xMid 250 mm no rebate baffle

NS-1000MM mid hor directivity pos
NS-1000M mid directivity hor neg

ringing peak at 3kHz in the tweeter
It's even more interesting. There is no ringing in NS-1000M tweeters, yet in NS-1000X there is. Maybe something change in production at some point.
NS-1000MM tweeter FR 50 mm bare dome
NS-1000M 2xTweeter 250 mm no rabate baffle 0 and 45 degrees
NS-1000X 2xTweeter - original and copper VC

(measurement conditions and comments in the filenames)

Anyway, the resonances do not affect directivity.
 
  • Like
Reactions: 1 user
An interesting point. I have measured and taken apart (to repair dislodged magnets) several midranges. There indeed should be no 1.8 kHz mode; also, I fired up a qucik VituixCAD sim to check midrange diffraction, and it shows no issue there.
Thank you for sharing, appreciate it.

Yeah, the center pole piece is a separate part. Were it possible to devise an insert to hold the pole piece and make it impossible for it to shift, it would be a great way to ensure the longevity of the drivers.

It's even more interesting. There is no ringing in NS-1000M tweeters, yet in NS-1000X there is. Maybe something change in production at some point.
That is interesting. The last of the FX-3 tweeters also have the peak at about 2.4kHz, but it doesn’t appear to affect them in use. A notch filter is one way to remedy it, but it seems to be a normal behavior for those specific driver models and years.
 
Why drag the NS1000 into a discussion about the NS5000?
They are completely different speakers.Almost nothing is similar other than they are manufactured by the same company.
The NS1000s never were very good.They have terrible imaging and use a woofer with a low Qts in a sealed box which is never going to be optimal.
A lot of speakers from that era were flawed in obvious ways like that.The JBL Century L100 was even worse.
I have never understood the appeal of those two speakers and why they would be considered as "classics" by some people.
Of the older Yamaha speakers the NS75T was a much better speaker in every way [I have owned both/still own NS75Ts]
The NS5000 is an excellent modern speaker without any of those quirks or flaws.
 
Above:

I basically agree with everything you said - except your comment regarding low Qts and sealed enclosures.
To get decent bass out of 'smallish' sealed enclosures, low Qts woofers are an absolute requirement :cool:

It has a Qts of 0.28.That is very low for use in a sealed box.A driver with that sort of Qts would almost always be used in a larger vented box.
I know a bloke who has built a much larger ported box for his and he much prefers it that way.
 
Troels Gravesen modelled -6db at 30 hz in an 80 litre vented box.I think for most people and rooms that would produce a better balanced sound.
-3db at 50 hz is getting into the area of sounding obviously bass-light.
I own Dynaudio C5s which are -3db at 47 hz [sealed isobaric] and designed to be used close to the corers/walls to get room gain.They can sound a bit bass light too in the wrong room but sound a lot fuller and less choked in the bass and better balanced than the NS1000s .

Of course a good subwoofer will help fill in the bottom octave in these types of speakers and tends to be relatively easy to get to integrate [unlike a lot of ported speakers].You are still left with the quite poor imaging of the NS1000s however.A shame because in some aspects they sound fantastic
 
For some reason nearly ever Japanese "large" speaker (and a lot of non-Japanese too) I measured had the same 50 Hz@-3 dB extension. Even the larger ones like Sony SS-G7, Diatone DS-5000 or Fisher STE-1200, which are definitely out of "big bookshelf" category. Maybe some weird national sound preference, or maybe all the designers/manufacturers had an unspoken agreement, or they thought it will integrate better in a small room. Have a hard time imagining DS-5000 in a 12 tatami apartmant, though.
Sony SS-G& T-S modeling

In general, I agree: 12" in a sizeable box should (and can) provide lower bass cut-off, it's definitely doable to get 35-40 Hz without compromising sensitivity. However, for given TS