Orelino / Orelo MKII Fletcher-Munson Curves

[vrao]

Hey Peter,

Thanks for the shout! 

The practicality of this is astounding. Though we know all the theories on the FM curve, it's application actually has not been performed to this level. And in practice, this actually brings in "unique" results, unlike anything on the market. There is more to be discovered! These speakers open new possibilities.

VJ

[vrao]

Let me reemphasize the importance of FM curves. It is nice in a way Peter/Bert have made it happen. On the fly one can change the settings, long behold, flat frequency response actually sounds bad on most recordings. Dialing it around FM helps with a more meaningful recreation of the signal. Meaning, the way these speakers play music, one can easily say somethings wrong with the recording, hum .... manipulate the curve, and yes one can recreate the recording event.
The speakers, amps FM curves and crossover work quite seamlessly. The different permutations on the FM curves makes it a very powerful tool for plaback. This would be impossible in seperate or different speaker/amp matching, where there is only one result, which is not calibrated for.

And yes, I've yet to discuss "Bass"

[CoenP]

Let me reemphasize the importance of FM curves. It is nice in a way Peter/Bert have made it happen. On the fly one can change the settings, long behold, flat frequency response actually sounds bad on most recordings. Dialing it around FM helps with a more meaningful recreation of the signal. Meaning, the way these speakers play music, one can easily say somethings wrong with the recording, hum .... manipulate the curve, and yes one can recreate the recording event.
The speakers, amps FM curves and crossover work quite seamlessly. The different permutations on the FM curves makes it a very powerful tool for plaback. This would be impossible in seperate or different speaker/amp matching, where there is only one result, which is not calibrated for.

And yes, I've yet to discuss "Bass"

To some extend this FM "correction" can be done in the digital domain too. This opens up the possibility of coupling the intensity of the FM correction to the volume control position...

Not that this is my idea. Like many things we just have to look back a couple of decades for the great ideas (and poor execution). I've got old Philips tube amps form the late 50s and they all have a "physiological" volume control which intends to compensate at least the bass for FM. Actually the engineers of those days saw the tone control (Baxandall) and later the "loudness"  button as a means to correct for FM rather than to compensate for the loudspeaker tonality or disco boosts. Quite crude and ineffective measures compared to the sophistication that the Orelo provides, yet a digital solution may hold even more potential.

regards, Coen

[xp9433]

Peter
Just checking with you about ongoing development of the NOS1(a) if you only use the Orelo MkII (with FM adjustments) for your listening tests. Effectively you will be seen to be using FM "EQ" type adjustments to make the music sound as best as you can in your listening environment at your listening levels.

While this may be a great option for the few Orelo owners, it will not necessary give you the same insight into how your NOS1 sounds compared to other DAC's using "ordinary" loudspeakers.

However, knowing how you operate, I assume you have this covered.

Cheers
Frank

[vrao]

Hi CoenP/XP,
You are indeed correct, there are many ways to skin the cat.
However the direction Peter took makes in unique, since it is accurately calibrated on the speaker, it is reproducible.
Otherwise one has to work with the specific transducer, it's characteristics, crossovers, speaker design, and the results may vary so much that it might might not make sense. There is much to add to this, all in due time.
Kind regards,
VJ

[PeterSt]

Hi there Frank,

I think it is the other way around. I't like I said two days back : with the again better speaker I can hear better what can be improved. Notice though that I put that a bit differently : "I needed to improve the NOS1" and "after that happened I needed to improve the Arc Prediction Filter". So improve one and hear how the next now needs improvement.

I know how unreal this may come across but it is also about the level we're at these days. Like VJ said "you can only compare with real music(al instruments)" (similar). Or how it was clear right from the start with the NOS1 that not only me, but people in general could far more easily hear where the next culprit is (assumed there is one and there always is one of course). But all is related to a reference and in this case that reference could use some upgrade. It is just audible but needs experience of course (way much actually).

And so in my view everybody will benefit. A better DAC is a better DAC. But thinking in the same realm, now people may be able to hear (better) that an amp needs an upgrade. And that's not a bad thing per se. Usually the only probem is "how do I tell my wife", right ?

Peter


PS: That last remark can come across as sour to some, so I know that. But in this hobby I think it is the general idea ...

[CoenP]

There is much to add to this, all in due time.
Kind regards,
VJ

Hi VeeJay,

Thanks for the reply. Looking forward in quiet anticipation!

regards, Coen

[xp9433]

[/quote]
I think it is the other way around. I't like I said two days back : with the again better speaker I can hear better what can be improved. Notice though that I put that a bit differently : "I needed to improve the NOS1" and "after that happened I needed to improve the Arc Prediction Filter". So improve one and hear how the next now needs improvement.
[/quote]

Peter, Perhaps I am not expressing myself well. And no criticism is intended in my questioning.

I have no doubt that a better speaker will help you develop a better DAC. I have no doubt that the highly transparent and revealing Orelo MkII have made the evaluation of any deficiencies in the NOS1 easier to identify and help you in your quest. I have no doubt you are achieving extraordinary SQ results through the Orelo MII speakers with the NOS1a. Absolutely trust you there!

However, I still have a question relating to 'balance and neutrality' for the DAC.
Take this example (made up case only): How do you know you are achieving the right bass weight/drive from the DAC, if you are using speakers, no matter how revealing and transparent, that are themselves not voiced neutrally?  That is, a perceived bass lightness (no matter how detailed and dynamic) from the DAC could be compensated by (and potentially masked by) FM adjustments that lift the Orelo's bass response. The result, a fabulously weighted & dynamic bass presentation in your room at your critical evaluation listening levels.
Nevertheless, your extraordinarily revealing DAC might be perceived by others to be bass light with other speakers/systems - no matter how detailed/revealing the DAC.

Hence my question about you using another recognised "neutral" speaker in your development evaluations for cross-checking the NOS1a's performance against other DAC's.

Final comparison: Your NOS1a/Amps/Orelo MkII "System" might give the best "system performance & quality" available anywhere. That doesn't automatically guarantee that you will have voiced the NOS1a DAC to be recognised as providing the best "DAC performance & quality" available anywhere. You probably have achieved that though, and I look forward to future feedback from the many new NOS1a users - without Orelo MKII speakers.

Cheers
Frank

[PeterSt]

Hey Frank,

I suppose I have an answer to that too, but it really needs some thorough work out and of course longer post.
So I'll be back !

Regads,
Peter


PS: Question is fully justified of course !

[PeterSt]

Frank, an attempt :

As you may have read (topic elsewhere) I even dare talk about a neutral speaker. I recall even adding "100%" to that. Yes, super dangerous and maybe not realistic to begin with.

You are one of the happy few that sort of dares to pose the question; as you will know, elsewhere this goes differently and some (often extensive) justification is needed. Not much in my own forum. But I guess this is because of that other happy more "believe" better to begin with because they hear it (coming) themselves. So elsewhere I have to explain a 1000 times that any DAC serving the frequency domain is killing the time domain while it is all about that (killing). And no matter you should have been the very very first with a NOS1, it never happened and now you can't "see".
Side note : If anyone with a NOS1 disagrees the slightest, let him speak up. No problem !

So my point is : The DAC is neutral and with a bit of luck "100%". It also measures that (all *is* about measuring) and the amps used do as well. So no reason to not tune a speaker to that while a speaker is not much inherently neutral at all. But the THD figures also easily show that ...

Side note again : I know of no amps that measure neutral as well, but one (the Sauermann). Of course I haven't seen all, but it may be an indication that all what we listen through is not neutral for measurements to begin with.

This was the easy part; The FAR more difficult part is how to explain that a DAC which is regarded completely neutral world wide (this just is so and otherwise waiting for the first to come up with some sort of "complaint" regarding this) ... how such a DAC can be improved upon. So just telling : I am not good at that because it requieres wording which may not be in my vocubalaire. But I think "timbre". Now, timbre IMO will hardly change while in the mean time jitter causes all sorts of "anomalies" elsewhere. Like sound being too harsh (after all and after all we try with XXHighEnd for example). We could say that the more harsh sound implies a nature to the sound, but we don't recognize it as that. We only do once the culprit is out of the way. Like W7 was so good. But not any more since finally W8 started to be good. Get what I mean ?

So a typical example of less jitter (for me) would be "more real again". Timbre did not change, harshness probably got better, but things play together better. But is still neutral.

Before I go too wild on this, it now is crucial to understand that a combo DAC/Amp - but actually also playback software, can be regarded as neutral, or at least neutral enough to right away hear where a speaker (last part in the chain left that can influence) is not neutral at all. This really is easy.

The last part of the story is that when a speaker changes from 115dB sensitive to 118dB sensitive, this implies such a huge change on the HF output (all just flows out so much more easy) that while this with 115dB was hold back, it now does less and e.g. harshness becomes more apparent. It is just louder.
Remember : A piano plays at 90dBSPL live and a cymbal does 110dB. With an 80dB sensitive speaker the cymbal may sound at 60dB while the piano still plays at 90dB (this could be exaggerated). But when the speaker gets more senstive (all moves more easily) the distance of the piano and the cymbal gets larger; the cymbal travels towards reality level outputs (and let's be happy when it never happens really - a cymbal is LOUD). Last thing to understand - which is not difficult - is that when the cymbal sounds louder the implied distortions from the rest of the chain also sound louder. This has been the problem forever (for me). So what can be wrong when things now don't sound right ? the speaker ? no, in this realm not. So it is the remainder. DAC is first. Why ? because we KNOW it is subject to all the noise sh*t we ever so much talk about in this forum. So let's solve that.
Done ? now it becomes apparent that serving the time domain for 100% is again nog te best for hearing distortions. Why *this* conclusion ? well, it can't be the PC any more, it can't be the playback software, so ot has to be the filtering (which is in the playback software, but in another dimension of it).

It is almost simple math. So :

Nevertheless, your extraordinarily revealing DAC might be perceived by others to be bass light with other speakers/systems - no matter how detailed/revealing the DAC.

Yes, and sadly it is just the truth. No bass can be too light when it measures well. But also and merely : No bass can be extended when the speaker can't do it. Read that topic/posts about me explaining what woofer surface must be in order to represent a kick drum for reality ? That. It can't be done otherwise unless with super heavy distortion (which is in all of our speakers) and so this too is easy.
So NOS1 *is* bass light because speakers are. Change that into a normal DAC and ... NOT neutral. Bass-light is also not neutral but personal me looks through that. Again remember W7 ? more bass. who can stand it ? nobody Why ? because now it distorts.

Still too short for all the real answers (and many typos I'm afraid) but this is how I "work".
All is also how I dare to call the MKII neutral, because my ears tune it like that in the first place (this is the DSP part and btw not the F-M Curves) BUT I also measure THD. And *that* now is crucial.

Sorry if this is all too confusing - I know it is without the implied references. But what to do.
Best regards,
Peter

[christoffe]

The last part of the story is that when a speaker changes from 115dB sensitive to 118dB sensitive, this implies such a huge change on the HF output (all just flows out so much more easy) that while this with 115dB was hold back, it now does less and e.g. harshness becomes more apparent. It is just louder.

There is more involved:

http://stereos.about.com/od/stereoscience/a/amppower.htm
http://electronics.howstuffworks.com/how-to-explain-speaker-sensitivity.htm

[PeterSt]

People,

I don't even dare to read back, but I'm sure that last post must be quite "odd" to say it mildly. I wanted to do it later but saw 5 minutes od spare time yesterday and I wrote that in really 5 minutes. It *is* what's in my mind though, but this was shouting from a high mountain to you. Too fast.

I will still keep it brief now, but I'll try another way.

DAC is still neutral. It was created on totally flat measuring amplifiers (look at noise line) and the process of "tuning" the speakers I used back at the time is a process of years and learning what comes from the speaker and what from the DAC. But, DAC is also measured all the time and this is with the focus on the time domain - no ringing. This is crucial because all what rings also colours (not neutral). What remains from anomalies in the frequency domain can be harshness. This expresses better when the speakers are more fast. The more sensitive, the more fast they are. DAC is as fast as possible (this is time domain stuff again).

When this is all in balance all should sound neutral. Neutral is : Play for a week all types of different music and hear no similarities all over. This is my main tuning means, also with XXHighEnd changes.

It is NOT so that e.g. too much bass in a speaker is explictly compensated by e.g. XXHighEnd means. Also not DAC means. This is just not possible because of the pure technical means used for DAC and software. These means for example "as fast as possible" which often is a deriviate of as lean as possible. If now more or less bass springs from the speaker, so be it. But please remember, it is YOU ALL who determine this. Me only as a very small part. So if at some stage one says "better bass" you can almost bet everything on it that all will say better bass. This is how "better" is determined. One big A-B company.

I am not tweaking my NOS1 all the time; I keep it the same as yours. This is on purpose or all would be moot.

With my reference of neutral, which is all confirmed by you out there, I may proceed. So you don't complain and I don't either. Now, new speaker. Does not sound neutral at all and why would it. It wasn't tuned for that. But I know the rest of my gear and that it is able to do it.
... now envision the process ...

Nothing works, but the speaker is quite similar to what I had and the filtering in there which has been a process of years can be applied to the new speaker. Aha, that works. But only as a base. There's lots more of tuning possibilities so in many months time it starts to be good. Better.

While the above can be seen as all audibly tuning, now measurement comes in. This is related to it being a commercial speaker and no "my room" or "my ears" are allowed to play a role. So measurements explicitly to not incorporate room response. It becomes a very technical thing now.

Major part of this is how the bass response is tuned, which merely means "how it is measured". That needed something odd but in combination with listening to the resulting tuning I found a way how to measure so that what I measure for the better also sounds for the better. However, this is super simple because it is not about tweaking out anomalies - it is only about tweaking *in* all for the better. Like how to go straight to 19Hz. One thing : the whole bass section has to match the mid and *that* only goes audibly. Why ? because they can't be measured together which in itself is related to not wanting to measure the room.
Now another technicallity was applied : making the XOver so that the bass section allows for linear volume up/down while the XOver keeps on "working".

This latter tuning of the bass against the mid(/high) also takes weeks. That ends with maybe once in 3 days another 1dB more and later one half less and more again, until nothing disturbs any more and all remains neutral. Remember : nothing sounding the same. Nothing bass heavy, nothing too lean. What remains is that one recoding just *contains* more bass than the other, but no way you have the idea to tune in more bass. It is just not in there and you know it.

Then the next round comes and it is about knowing that the speaker is OK while you can also hear it can sound better. Nothing much different from sitting down for another XXHighEnd tweak with one difference : I don't know of any more XXHighEnd tweaks at this moment. So what to do ? improve the DAC because we all KNOW it is there why and how XXHighEnd can influence. So eliminate that influence finally.
And I could even do it.

If *now* something sounds wrong and still knowing it can't be the DAC, it must be the filtering. And easy, filtering makes the sound and is the reason why the NOS1 sounds as it does in the first place. So it is the last thing to improve upon, thus now that.


I said the same as yesterday but now maybe in a less shouting form and is is the truth.
It "just" can work like that but remember it is actually a process of many many years *why* it can now work like that. And it becomes more and more easy.

To hopefuly better answer the question which was key I think : No DAC is made more or less bass heavy. It just does not work like that. It is only made "better" with assumptions like more speed = better and less jitter = better. Stupidly that.
Speaker almost the same; find out what THD is audible plus find out a means how to check that (all written out somewhere) and make it so that THD stays under that. Super technical things and nothing subjective. The only subjectivity in it is that I say it should work like that. This is for example different from someone who says "but it should be tubes".

And in the end all is based upon not attacking distortion with more distortion (which smears the first) but getting ALL right.
I did not say it is easy and I especially did not say it is easy to understand.

Regards,
Peter

[PeterSt]

I am measuring the first production unit of the NOS1a anyway, so this is what I mean with a straight noise line.

In this (NOS1a) case also without any anomaly anywhere. Only some 50Hz mains pickup.
USB is streaming here.

An amplifier should add nothing to this (now new peaks); only gain.

This could not be done before and what it should tell us is that this now is a reference. Meaning : When any next NOS1a shows something here, it is not right. Simply : because it can be done apparently.
And FYI : Yesterday this was not the case (didn't make screenshots of it). So *now* pure theory comes about : It should be like this because of the total isolation and when all soldering is right nothing can show. Of course it takes more like the components used and PCB layout etc., but we shouldn't underestimate the reference this now brings. I know, it is a technical reference but in the end all is; My previous posts were all about references although from different angle and in different realms/domains. But once you have such a reference it will be the base for the next development. So for example, a next development may bring down the noise more. Nice. But now peaks show again. And thus the next development will be about bringing down those peaks. And so on.

Low noise so what ? well, think about how 24 bits can resolve. This can only be done when first the noise is lower than that (-144dB).

And so we continue ...
Peter

[vrao]

Playing with these speakers for about a week, I'm getting more and more acclimatized to its capabilities. I can probably see where the NOS-1a can enhance playback, there is a very small margin, ;-) (but probably an important milestone, considering Peter's response).
Mani, let me know your thoughts when you have your NOS-1a

I know Peter talks about cymbals all the the time, it actually took this setup to understand where he is coming from, this probably would relate to the high sensitivity. Considering cymbal clashes require enormous power requirements for ultra short period of time, I think this would be the forte of high sensitivity speakers for playback at realistic levels. Recording mistakes with enhanced hi frequency is easily seen, such as cymbals, which all of a sudden stand out in a recording, probably because the speakers used in the process did not have necessary dynamic intensity for realistic playback.

[christoffe]

 this probably would relate to the high sensitivity.

In general the SQ of these speakers must be amazing, but there must be other explanations than the high sensitivity only.

I came across a film report about Gauder Akustik, and Dr. Gauders argument about a good SQ is different.

http://www.youtube.com/watch?v=rnYa83UOvG4

Start the film at 3.30 minutes and watch ……… .

Joachim