Full Range speaker project

[Overkill Audio]

Happy New Year!

Sorry I forgot to wish everyone a Happy New Year....I was still a bit groggy from last night!

Rafael,
No worries on the traveling as I am only 10 mins from St Neots train station so I can pick you up and take you back.

As all my speakers share the same core technology and cabinet construction techniques they all share the same sound....Just more of it the bigger the speakers!
I believe its a very natural and life like sound which is both exciting and relaxing to listen to, depending on the music being played.

I am trying to stop gushing about my designs as I am biased, so I simply say to one and all come and have a listen and then you can tell everyone else what you think!

Bring along your Kef speakers and we can compare them to the BMR's, I have heard them at shows but not had a pair home yet so always happy to compare.
I heard a two way using Satori drivers a few months ago, it was a very difficult comparison with two different systems and not enough time to set up properly, but I heard enough to be impressed with Satori drivers.

I am not able to comment on most modern audiophile drivers as I dont use them!

All the best
Derek.

Hello Derek, that's a lot of information and thank you for that. Also thank you for such a great opportunity to come to your place to hear all these outstanding speakers. I would like to come that would be fantastic but unfortunately I don't have a car but if I only could find any cheap train or bus I would like to come definitely. All three models look great. If you could choose the best one from these three models which you sent me in pdf which on would you choose for overall sound and music quality ? I am curious how the last pair with 4 bmr would compare to normal 2 way system like on your pdf also with 10" woofer or 15" woofer. ?

Also how these BMR drivers comparing to scan 10F/8424 ? Which one is better if that is a good question ?

I would like to meet and know some diy audio guys here in Leeds or around Leeds but I don't know anyone. Do you know anyone around Leeds ? And that's true it is always very nice to meet new peoples or have new friends especially when audio lover meet another audio lover.

Thank you very much Derek for your input,

All the best and Happy New Year !

Rafael

 

[BYRTT]

The most expensive but not not near the best.

dave

Different taste if we take out most expensive and talk highest value and performance TC9FD right : )

FF85WK probably a very nice performer, but have you any data to share for why 10F is as you express killed by a FF85wKeN and why when looking at below compared frq plots why one of them is only a midrange but not the other one.

Below is manufactures objective datasheets for stock FF85WK verse 10F/8424 stretched to same scales, below each plot is placed some scales to show X axis was quite right before aligning Fostex plot Y axis to same scale as SS plot. Then in picture 2 and 3 is 64 watt into those two drivers and their excursion limits, add virtual a XO point and think about possibilities when some distortion components starts to kick in.

 

[planet10]

highest value and performance TC9FD right : )

It is cheap. And it doesn't cost much. But it is not all that good. Whole swaths of lower level detail MIA. An excellent set of design compromises for the target market -- inside TVs wher ethe source is often lacking. Those that love it tells us more about the listener than the speaker. Fine for them is they enjoy it. I found them quite compromised for hifi use.

I know there is a whole school that worships at the alter of flat frequency response -- it is important -- but that is only looking at the surface. Like trying to evaluate how much water is in a lake by only looking at the surface. There is a whole lot more there.

Hard to compare the charts -- not the same scale & who knows how close the measuring conditions were. The sims show significantly lower bass from the FF85wk. The FF85 will have course have greater excursion because it goes lower with about the same cone size.

when some distortion components starts to kick in.

We don't much care about distortion as we measure it for speakers… it tells us very little.

dave

 

[BYRTT]

It is cheap. And it doesn't cost much. But it is not all that good. Whole swaths of lower level detail MIA. An excellent set of design compromises for the target market -- inside TVs wher ethe source is often lacking. Those that love it tells us more about the listener than the speaker. Fine for them is they enjoy it. I found them quite compromised for hifi use.....

That TC9FD datasheet have TV as application printed you often use as argument to kind of looking down on the product and listener, can't say other than find it little misused argument as if i said that stamped steal frame on FF85WK is hopeless verse casting on 10F and also can imagine in reality many good components started targeted other fields then later adopted other high performance products.

.....I know there is a whole school that worships at the alter of flat frequency response -- it is important -- but that is only looking at the surface. Like trying to evaluate how much water is in a lake by only looking at the surface. There is a whole lot more there.....

Right there's much more water under than just looking at the surface of a lake and can be measured with a volume standard so we can compare to another lake.

First arriving waves direct sound from a speaker is normally minimum phase type and there frq response is directly connected to timing and wave shape reproduction performance, this direct sound frq measurement makes up for a standard to measure speakers acoustic performance as volume standard do for measuring above lake, unsmooth frq response and especially high Q peak and dips think makes changes to standard and reproduced wave shapes.

.....Hard to compare the charts -- not the same scale & who knows how close the measuring conditions were. The sims show significantly lower bass from the FF85wk. The FF85 will have course have greater excursion because it goes lower with about the same cone size.....

Okay fair regarding compare charts but on the other hand those two brands datasheet are often close to diy home environment measurements and wonder in that you have both can share some under same condition data, FF85wKeN also welcome. But regarding linear excursion can't you see FF85WK have quite some less advertised linear travel compared to 10F.

.....We don't much care about distortion as we measure it for speakers… it tells us very little.....

Okay your opinion, if you find the time and curiosity try this fun KLIPPEL Listening Test.

 

[planet10]

stamped steal frame on FF85WK is hopeless verse casting on 10F

There is no question that the 10F is well built. The steel frame on the FF85wk is cheap, but really well engineered to get the most out of the format. In the end what matters is what they sound like. 10F stock is still more expensive than FF85wKeN and doesn't sound as good.

Stock i don't know. But 2 stock FF85wk cost about the same as a single 10F.

Right there's much more water under than just looking at the surface of a lake and can be measured with a volume standard so we can compare to another lake.

But we have yet to have a measure that does the same for a speaker.

First arriving waves direct sound from a speaker is normally minimum phase type and there frq response is directly connected to timing and wave shape reproduction performance, this direct sound frq measurement makes up for a standard to measure speakers acoustic performance as volume standard do for measuring above lake, unsmooth frq response and especially high Q peak and dips think makes changes to standard and reproduced wave shapes.

No it doesn't. It only tells you how flat the surface is.

But regarding linear excursion can't you see FF85WK have quite some less advertised linear travel compared to 10F.

Moot. What matters is what the whole does when you listen to them.

To quote Floyd Toole:

Two ears and a brain are massively more analytical and adaptable than an omnidirectional microphone and an analyzer.

dave

 

[larryldspkr]

All things considered, the FF85wk has a more even tonal balance. The 10F may need some passive correction (bsc) to sound balanced.

Larry

 

[BYRTT]

There is no question that the 10F is well built. The steel frame on the FF85wk is cheap, but really well engineered to get the most out of the format. In the end what matters is what they sound like. 10F stock is still more expensive than FF85wKeN and doesn't sound as good.

Could be wrong but if high passed 400Hz or higher personal consider frame construction for FF85WK close to perfect executed for application, so therefor sorry think my English language skills spoiled some the context and what i meant saying that sentence. Seems we agree 10F is well build and FF85WK well engineered and probably the other way around too, also in the end what matter is what they sound like, next is of course respect your personal taste and preference for FF85wKeN and also like its lower cost but have hard time imagine 10F doesn't sound as good.

Stock i don't know. But 2 stock FF85wk cost about the same as a single 10F.

You right 10F is costlier and that is good point, but regarding this thread OP ask to improve his sound from pair KEF LS50 which I'm not sure is easy and at same OP have pointed to and approved budget for a pair 10F.

But we have yet to have a measure that does the same for a speaker.

Okay a free world and your choice deselect science and industry but think it gets impossible to make any progress for speakers at all if you don't accept acoustic measurements and there coherence related to electric domain measurements and find it weird world shall rely and trust only your ears as a reference point to measure acoustics with precision resolution.

No it doesn't. It only tells you how flat the surface is.

Yes this is acoustics but you have a design axis to work with and when that gets good you measure deep and get better direct sound. Tell me can your ears in a point in space on design axis calibrate power full DSP filters so as speaker systems offset is perfect and speaker system reproduce acoustic square waves from very lows to 4kHz or more, don't think so but that can a measurement system do and you say it only tells about surface.

 

[planet10]

but have hard time imagine 10F doesn't sound as good.

The magnitude of the differences i found surprising.

if you don't accept acoustic measurements and there coherence related to electric domain measurements and find it weird world shall rely and trust only your ears as a reference point to measure acoustics with precision resolution.

The ear is the final arbiter. (Henry Olson said that). I do accept acoustic measurements but i also understand their limitations -- which many don't seem to.

dave

 

[BYRTT]

All things considered, the FF85wk has a more even tonal balance. The 10F may need some passive correction (bsc) to sound balanced.

Larry

Thanks info perceive message as so is performance those two drivers period.

Is this analyze and proposed correction filter based on instruments ears or some of both.

Will have to buy a pair those Fostex to have a listen their sound.

 

[wesayso]

I know there is a whole school that worships at the alter of flat frequency response -- it is important -- but that is only looking at the surface. Like trying to evaluate how much water is in a lake by only looking at the surface. There is a whole lot more there.

We don't much care about distortion as we measure it for speakers… it tells us very little.

dave

Let me provide a view from the other side. Known as the boys at the alter of flat frequency response.
We do have our reasons to believe that, but we do have to look at more than frequency response alone to get the satisfaction.
Once you start to realise what audio really is you can learn what you need to know from that impulse. It tells you what it is you are listening to. So you don't have to depend on the variable EQ that the current driver of choice applies to your favourite music.

Look a bit harder at the impulse, willing to learn something from it. See what it does in time, use the filters in the filtered IR views to know what the driver is doing to your favourite songs after those notes. We wouldn't want to change the sound of a cymbal in our song, so to hear it at the right level, the frequency response needs to be flat enough. But we also don't want the duration to change. So on to the waterfall to see if there aren't any ridges at those frequencies that could make the sound of the cymbal hit sustain in time.

Look at posts such as this one to know more about how we get to hear our drivers:
http://www.diyaudio.com/forums/multi-way/279921-worlds-best-tweeters-face-off-subjective-comparison-27.html#post4562980

Hi all!

Just wanted to comment on a few points in comparing distortion in loudspeakers.

First of all, the method we measure and present distortion data is borrowed from measuring amplification stages.
While it is OK to use it in electronics, it's pretty much invalid for speakers. Speakers have stored energy, while amplifier doesn't.
The distortion measurement for a speaker is meaningless if it is not multiplied by decay time.

for example, most hard cone bass-mids will have a peak at the end of bandwidth. Say, a 8" magnesium cone rings 10dB at 4.5k.
It will have 0.5% of 3rd harmonic there. That 3rd harmonic will come from a 1.5k signal that was applied to motor.
So, you apply the signal, it generates a 3rd harm, then stop the 1.5k signal and your 3rd harmonic gets to ride on top of response 4.5k peak and last 2ms after the signal stopped. Now, what a 0.5% distortion actually means in that case? Pretty much nothing, as that will sound like nothing we can relate to. It's not a "timbre" any more, it's a horror story.
Now, that is an extreme example, nevertheless, all moving systems will do this to some extent.
It is of utmost importance to reduce energy storage in pass-band and if it must exist, decay must be smooth, with the least amount of "ridges" appearing in CSD.
That will dismiss the impact of distortion lasting than the signal that caused it. That is the primary objective of my tweeter design.

As for the amount of distortion, yes, a tight flat ribbon will initially show greater distortion than a corrugated foil ribbon.
Provided that those two ribbons, have the same decay (they don't, corrugations have breakup), the flat tight one will be worse if you listen to music at 85dB level with no dynamics (Bob Rock?).
However, if you do listen to music that has dynamics, more important part is whether the tweeter will change the "nature" of it's distortion with increasing level. Tight flat ribbons (when properly suspended in homogenous magnetic field) do not appreciably change the distortion spectrum, while corrugated ones tend to "explode" into distortion after a certain level is reached, and it is reached all the time in normal listening.
So, a speaker wit initially higher distortion will sound clean if the distortion rises linearly with level and it's spectrum doesn't change.
That's because the distortion in ears change in a similar way.
Only at that point, I can dare to speak of whether a tweeter has colorations, but if it does what I described, it will sound clean, nevertheless. With a "timbre" perhaps, but still exceptionally clean.
This was the secondary objective of the tweeter design that I do.

All other things that we value in tweeters come naturally if you sort out these two things, and you can play with variables later (response shape, dispersion, bandwidth...), as they are in a far third place.

Here is the THD vs. SPL of RAAL 140-15D, without foam pads, crossed with 4th order at 2k5:
Note the THD spectrum and amount vs. SPL. That's the point when we talk audible distortion, not whether we're having -40, -50 at 85-90dB SPL.

So, a full picture can be grasped from (CSD x (THD vs SPL)) and distortion in speakers takes a whole different meaning and interpretation.
Discussions of it becomes pointless with looking only at data fragment gotten by measuring methods borrowed from electronics.

Cheers!

Even though the above is about well designed ribbon drivers there is a wealth of info in one post on some of the important stuff for us, the guys at the alter of flat frequency response.

Once that sinks in we may start to understand why each driver sounds different, even when EQ-ed completely flat! Why cone materials have a sound of their own, etc.

It's all there for us to explore. So we don't have to rely on a driver to apply it's signature sound to our songs.

If we look at what Larry said about the 2 drivers in the plot's from BYRTT it tells us we, or at least Larry might not like the 10F's slightly rising response. But we can cure things like that. The Frequency Response is excellent, look at the other graphs as well, it is an exceptionally clean performer even for it's price. It still holds up if you start to look real close. It becomes apparent why we pay the price for a driver like that. They actually knew what they were making here.... Would this be the same bunch behind those Satori drivers mentioned earlier in this thread?

As well as that little TV driver, the TC9FD18-08. Not as good as the Scan Speak 10F, but quite clean and honest especially for it's price. Brought to you by that same bunch that created the 10F. Designed long ago under the wings of Scan Speak it's quite the marvel. Again it has a slightly rising curve that may need to be adjusted to taste.

There's more of coarse, but this might give a bit of insight from the alter of flat frequency (and many other variables that determine the sound).

The magic? It's right there, in the original music. As it would be at a "live" performance. The job of our speakers is to let us hear that magic. Preferably unharmed.

We do believe that distortion plays a role in a driver's performance. Probably just like Dr. Geddes would, should he start using small full range drivers. We all know he considers audible distortion in well designed compression drivers irrelevant. A commodity product I believe. But read that excellent post by Raal I linked to again to know why it just may be of importance in our world of full range drivers.

 

[xrk971]

The 10F/8424 when horn loaded has even lower distortion and hits 20 kHz solidly.

Despite being perjoratively called a "lifeless tv speaker", the TC9FD, sans treatments of painted dots and magic gel coats, manages to produce, measured data of response, impulse, phase, Csd , that are the best in all of hifi audio at present. There is not a better speaker anywhere at any price at present than Wesayso's towers.

Here is measured Fr and phase at LP:

Here is group delay:

And here is the spectrogram:

 

[Scottmoose]

Without taking anything away from either the driver or the speakers in question (any), making blanket statements that xyz is 'best' is a sweeping generalisation, and fundamentally untrue. Such as for situations where it is utterly inappropriate, n'cest pas? There is no such thing as 'best' -just a series of compromises which the individual makes based on their specific requirements. Period.

 

[xrk971]

Welcome back Scottmoose.

Best from the alter boys of flat frequency (and phase) measurements. I have not heard the Towers in person, but those measurements tell me the step response is going to be a textbook broad right triangle, it will play piano guitar bass and drums accurately, it will provide exceptional imaging resolution, and will even play square waves.

 

[Scottmoose]

And the very best for 2016 to you and your family.

No doubt. But they wouldn't be much cop, for instance, in a 5ft x 7ft box room where the listener requires a compact desktop monitor. 'Best' does not exist. If it did, life would be somewhat easier.

 

[zman01]

Welcome back Scott.

 

[Overkill Audio]

Return of the moose!

Scott.

With all due respect, I see you are picking up exactly where you left off.....complete garbage!

Wesayso and his superb line array line loudspeakers represents the current pinnacle of DIY loudspeaker design and open source community design.

He has spent a huge amount of time, effort and money developing a cutting edge system. He has used advanced DSP and software in his comprehensive R&D and then incorporated this into the finished design via both source and loudspeaker management.

Plus he has then shown huge generosity of spirit by sharing every stage of development, all his conclusions, measurements and ongoing understanding of loudspeaker design.

Then there is you and your "contributions".....
I understand your outdated loudspeaker design niche (TL = 95% complex / expensive woodwork tunneling to exploit the delayed resonance of a "holy grail" driver) fails in every subjective and objective comparison against the modern time coherent / DSP management systems Wesayso employ's, but still.....

In automotive terms, Wesayso has designed an Audi R10 and shared it with all of us and you rock up and say so what, your "horse and cart" is better at ploughing a field....So what!

I suggest you stay in your 5' by 7 ' "studio" enjoying the fruits of your frugal horns whilst the rest of us enjoy music in real world rooms.


Derek.

Without taking anything away from either the driver or the speakers in question (any), making blanket statements that xyz is 'best' is a sweeping generalisation, and fundamentally untrue. Such as for situations where it is utterly inappropriate, n'cest pas? There is no such thing as 'best' -just a series of compromises which the individual makes based on their specific requirements. Period.
No doubt. But they wouldn't be much cop, for instance, in a 5ft x 7ft box room where the listener requires a compact desktop monitor. 'Best' does not exist. If it did, life would be somewhat easier.

 

[Spica]

I would have to side with Scottmoose--I have a problem with calling anything "the best",even when parameters are carefully defined. Furthermore,he didn't put down anyone,their work,or contributions.Scottmoose has contributed much to DIY,and hopefully will continue to do so.We are all entitled to our opinions,and are free to disagree with someone, but what amounts to a personal attack on him is uncalled for,and inappropriate for this forum.
Let's be civil.

 

[Scottmoose]

Derek.

With all due respect, I see you are picking up exactly where you left off.....complete garbage!

There is no respect whatsoever in that comment. It's downright rude. Please try to converse in a polite fashion.

Wesayso and his superb line array line loudspeakers represents the current pinnacle of DIY loudspeaker design and open source community design.

He has spent a huge amount of time, effort and money developing a cutting edge system. He has used advanced DSP and software in his comprehensive R&D and then incorporated this into the finished design via both source and loudspeaker management.

Plus he has then shown huge generosity of spirit by sharing every stage of development, all his conclusions, measurements and ongoing understanding of loudspeaker design.

Indeed he has, and it is a remarkable achievement. Please indicate, at your leisure, where I have said anything to the contrary. What I do reject however is the notion that any loudspeaker can be all things to all people in any situation. Claiming anything at all is 'best' is an insupportable generalisation. If a person requires a small desktop monitor, an 8ft line array is self evidently not 'best'. Quod erat demonstrandum.

Then there is you and your "contributions".....

How very charming. Now I recall why I left.

I understand your outdated loudspeaker design niche (TL = 95% complex / expensive woodwork tunneling to exploit the delayed resonance of a "holy grail" driver) fails in every subjective and objective comparison against the modern time coherent / DSP management systems Wesayso employ's, but still.....

Really? I was not aware that I only design transmission lines. Obviously the sealed boxes, reflex boxes, quarter-wave lines, horns (front, back, compound), open baffles and line arrays that I have designed over the years (several thousand, most for other people) all fall into the 'outdated design niche' you are referring to. However, I endeavour not to impose my opinion on other people, and make personal attacks on them when it does not align with my own preferences, which your post makes clear you know little about.

In automotive terms, Wesayso has designed an Audi R10 and shared it with all of us and you rock up and say so what, your "horse and cart" is better at ploughing a field....So what!

As noted, I merely take issue with any claim that xyz is universally best. Simple as that. Because it is not and can't be. It may be exceptional in its own field, but it's not all things to all people.

I suggest you stay in your 5' by 7 ' "studio" enjoying the fruits of your frugal horns whilst the rest of us enjoy music in real world rooms.

As it happens, I don't have a 5ft x 7ft room. That was purely an example of why sweeping generalisations such as 'xyz is best' without any qualification whatsoever does nobody any favours. Nor, for your information, do I own a Frugel Horn, or any of the cabinets on that site. At present I don't actually have a single-driver based speaker in the house.

 

[zman01]

We are all entitled to our opinions,and are free to disagree with someone, but what amounts to a personal attack on him is uncalled for,and inappropriate for this forum.
Let's be civil.

+1

 

[Overkill Audio]

Hi Spica,

My beef with scotts post is that he is technically wrong.

The last 5 years or so everything in loudspeaker design has been changed.... Availability of low cost high performance DSP and measurement software has revealed previously undiscovered facts and enabled new solutions to be easily implemented.

Wesayso's line arrays are an example of the new and correct way of doing things....In its most simplified form the fact of the matter is that :
Time Domain is more important than frequency domain.


This holds true for every loudspeaker....Big or small, nearfield, farfield and everything in between.
Scott disagrees with this....I say he is wrong!

Its not personal is just true.