Re: NFS Luna / Duo Follow up
Thanks for the update, Dave, and your due diligence to uncover the truth!
It has to be very gratifying to know that your huge investment in the NFS system is justified and that you don't need to rely on a anechoic chamber for truly accurate measurements.
Re: NFS Luna / Duo Follow up
Quote:
Originally Posted by
davef
I am most pleased with this outcome, it fully puts to rest this bothersome and somewhat obsessive issue for me.
Excellent confirmation Outcome, Dave...an Early Christmas Present for sure!!! :cool:
Ted
Re: NFS Luna / Duo Follow up
I'm glad to see that the NFS measurements match the SEAS anechoic chamber results. Way to put that concern to bed!
Re: NFS Luna / Duo Follow up
Quote:
Originally Posted by
Mag_Neato
Thanks for the update, Dave, and your due diligence to uncover the truth!
It has to be very gratifying to know that your huge investment in the NFS system is justified and that you don't need to rely on a anechoic chamber for truly accurate measurements.
It is indeed quite gratifying and I now have full confidence in trusting measurements we take with our NFS. It has truly been an interesting case study for me. From my early days, back in the late 80's using RTAs to measure speaker performance, then as technology and computer processing improved - using maximum length sequence analyzers and gating measurements, and to now - the Klippel NFS. I have to wonder what will be next and if I will still be at it say 20 years from now...
While I am not a fan of the ASR forum (it is just too negative for my tastes) there is no question that Amir has changed things in this industry for the better, (for the better with regard to manufacturers who care about developing higher performance products) Ascend has always been at the forefront of measurement technology, and while the NFS was a HUGE investment for a small manufacturer, a small company like us - I honestly wouldn't have it any other way.
Re: NFS Luna / Duo Follow up
Quote:
Originally Posted by
Shazb0t
I'm glad to see that the NFS measurements match the SEAS anechoic chamber results. Way to put that concern to bed!
I have been stressing that SEAS's measurements wouldn't match the NFS with regard to port resonance and that would have started an entirely new evaluation, something I don't have the time for. We also can't build our own chamber, we don't have the space or resources required.
... and now we don't need to :)
I get a good chuckle looking back about a decade ago, we had many customers request a front slot port version of the Sierra-1/Sierra-2. I had always tried to avoid slot ports as they are just so problematic. Fast forward to now, something as seemingly simple as a front slot port has resulted in a major investment in a complete revamping/update of our R&D combined with hundreds of hours of research.
Re: NFS Luna / Duo Follow up
Do you think you have an accurate understanding of why the difference between the NFS and MLSSA measurements? The original plots from your MLSSA and the ASR plots really were almost incomprehensible (not the least by you no doubt).
You've put so much time and resource into getting to the bottom of this issue, I'm just wondering if there is a layman's explanation that is able to help us in understanding the correlation between this new technology and what we hear? If you were to do a blind comparative listening test between Luna V1 and V2, would the average listener be able to tell them apart?
Again, thank you so very much for the incredible transparency of this investigative journey! I can't imagine anyone else that would have gone to these extremes to get to the root of this situation.
Jay
Re: NFS Luna / Duo Follow up
Quote:
Originally Posted by
petmotel
Do you think you have an accurate understanding of why the difference between the NFS and MLSSA measurements? The original plots from your MLSSA and the ASR plots really were almost incomprehensible (not the least by you no doubt).
Gating is a method of examining the impulse response of a measurement in a specific time window. By gating, we can limit the impulse response to a segment where there is no room influence (reflections for example). However, gating also limits the overall resolution, much like smoothing. In the case of such a high Q port resonance (very narrow, the resonance covers only a range of about 40Hz), it gets completely smoothed over. With no gating, the influence of the room then dominates (I posted these measurements but likely didn't explain it well)
In the frequency range of the resonance, the NFS uses Field Separation to remove the influence of the room. The operator of the NFS needs to set how many *points* per octave to use. CEA-2034 spec call for 20 points per octave, which in the range of the resonance, ends up being a resolution of 30Hz, less than the range of the resonance so the NFS calculates it. If we were to use, for example, 6 points per octave, that resonance would look completely different in the measurements. We can also set the NFS to much higher resolution than 20 points per octave.
The only way to measure this resonance with gated measurements, is to properly close mic it and not use gating. However, this also isn't accurate because being a narrow slot port, close micing it also picks up turbulence (different from the resonance). I believe I showed this effect in one of the graphs, comparing the port response at different close mic distances with no gating.
Thankfully, these complexities no longer exist for us because of our NFS.
Quote:
If you were to do a blind comparative listening test between Luna V1 and V2, would the average listener be able to tell them apart?
I wish I could answer that, everyone hears differently. I do not think the port resonance is/was audible, I never heard it and I am an experienced critical listener. However, I have learned to never trust my own ears and to never assume what anyone else can or can not hear. That said, the V2 version crossovers have been fully optimized based on using the higher resolution capabilities of our NFS. In that regard, they do sound better, warmer with a better midrange and I do think the average listener will definitely hear these differences.
I think both V2 models sound fantastic. I have several pairs of Luna's in my own home, all have been updated to V2 and nearly every evening I look forward to listening to music or movies through them. They are presently the speakers I listen to the most.
Re: NFS Luna / Duo Follow up
No one seems to want to ask the question. How much will the upgrade kit cost?
Re: NFS Luna / Duo Follow up
Quote:
Originally Posted by
davef
While I am not a fan of the ASR forum (it is just too negative for my tastes) there is no question that Amir has changed things in this industry for the better, (for the better with regard to manufacturers who care about developing higher performance products) Ascend has always been at the forefront of measurement technology, and while the NFS was a HUGE investment for a small manufacturer, a small company like us - I honestly wouldn't have it any other way.
Yeah, you and me both it seems. The overall tone of the ASR forum could use a major revamp. I can only imagine what a manufacturer goes through if one of their products receives a negative review. My guess is that they get a flood of negative comments thrown their way via email, phone, etc. If others like to post there, that's just fine by me.
On the plus side, there are some good aspects that will come out in the end and I appreciate you taking the time to improve the Luna & Duo speakers based on the feedback! In the end, the NFS system will definitely add value to your research and hope the payback will be sooner rather than later! That device does not come cheap!
Re: NFS Luna / Duo Follow up
Your obsession Dave, makes me obsessed about your speakers. To be very honest the Luna V1 sound great when I first got it on release day. But after Amir released his review they never sounded as good as before (All in my head). I'm sure he hurt some sales for your Luna. Not just for you but also me selling it second hand. I still considered it a win at the end of the day for you and me. It made me upgrade to the Horizon and it made you invest in the Klippel. End of story :)