[Ed Schilling]

I have a couple questions for you to consider and answers to ask…..

First off, you want to build a single driver speaker system. You think about it a while……and you think to your self….”self, what is the most critical part of the music “spectrum” that you are trying to reproduce?” Self says,  “why,  the midrange/treble, everyone knows that”.

So you think, ok…..so you look at midrange/tweeter drivers and electrostats and planar and horn drivers and ribbons and so on. And you think…..some more.

You are aware but maybe it never really sunk in……what do they all have in common?
(you have to guess the answer, sort of.)

Now the question is this…….why are there no “high mass” midrange/treble drivers?

Don’t some of them (midrange/treble drivers) have tremendous flux strength ? Can’t they handle plenty of “power”? I wonder if just maybe you want the moving mass  as light as possible too? Just a thought.

So…….where does the trade off between moving mass, cone area and efficiency merge into the spot that seems “right” for your project?

Does a 7 or  15 gram 6-8” tweeter sound like a good idea?  How about 3 grams?

Can you name a successful “3 gram tweeter”….I doubt it…oops….there are some paper ones that come close. And the 126 E will in fact do that job in a 2 way. Pretty damn well, I might add.

Would you consider (or have you ever seen anyone) using ANY 6-8 driver as a tweeter in a 2 way? Why not…..nothing magic is happening to the high end when you stick it in a box by itself.

So you decide to build a single driver system and you think….hmmm….how am I going to get that small driver to do what I want? Or that big one to pretend it is ½ a gram instead of 12 grams? Decisions, decisions……..

Light, stiff cones are not conducive to deep bass response and we don’t want to defeat the purpose of the single driver by adding a “shaping network”. So……more to think about.

So there you go……While a “large single driver speaker” may sound just fine,  for me personally, I can easily build a proper two way with higher efficiency, and deeper bass  with better treble and a MUCH higher max SPL than any “large format single driver speaker” has a prayer of doing. After all there is a nice thread on the “web” entitled “why a single driver speaker  can’t play metal”. And this is in regard to a “large format driver”. Again, certain designs can’t. A proper two way, in a cabinet that size,  could peal paint off walls. I know, I have built them.

A small corner horn loaded driver can play “Metal” too.

Hmmmm......I can build a much better 2 way than a "large format single driver" from a technical and practical standpoint..........But I can’t build a better 2 way than a small single driver that has the ability to go as loud I need.

When it comes down to it we go for the compromise that works the best for the situation. These are just thoughts and questions and something to think about if you are going to DIY a single driver speaker.

If anyone thinks that moving mass is not important in a single driver speaker (and therefore midrange/treble transducers as well since we are asking the single driver to perform their function) I would appreciate your thoughts as to why this is so.

I think it very important.....on the same level as cone diameter. How many times have we heard "there is something "special" about the 4 inch drivers"?

This is not an effort to convince anyone what they like…..just something to think about.

Ed

BTW....a "good" 2 way is only as good as it's cross over. This is not a problem....just more to learn and that is what DIY is all about.

[Graham Maynard]

Hi Ed,

Surely it is dimension which is most important at HF ?

Dynamic driver centre domes, whether for a tweeter or within the centre of a larger cone, are small in order to minimise wavelength related break-up across the dimension of that dome.

Due to their construction large diameter cones can become increasingly decoupled with increasing frequency, thus the total air/cone mass is not of absolute relevence for HF and the entire cone diameter could not then be considered as a 'tweeter'.

I put it back to you that this case is not defendable, and that it is cone shape/size related beaming which is the most significant problem with HF propagation, this arising from breakup modes plus delayed coincidental radiation from a symmetrical radius within the larger diameter *circular* cones with respect to their energised centre/dome.

Cheers ......... Graham.

[Ed Schilling]

Graham,
Exactly. No argument here on that.

 In addition to that.....suppose you increase the mass of the typical 1 inch dome to say 7 grams. We could do this with something like oh I don't know what do we have around.....hmmmm.....lead filings and PVA glue will work. Or lead fishing weights , bb sized, cut in half will do it too I think. You just might have to apply a few coats to get a couple grams extra weight.

Do we think this would have an adverse effect on transient response as spl increases as opposed to the untreated dome. If it did how could we overcome the extra mass? Could we? Does it matter?

 In this case let's assume the tweeter is behaving in "pistonic fashion" for the range it is operating in. The question is just one of light vs. heavy.....and the difference, if any,  in how the two might behave.

Graham, not trying to make a point to defend here ( ) just axing the questions, I like your answers so far! Thanks!

Ed

[Graham Maynard]

.....suppose you increase the mass of the typical 1 inch dome to say 7 grams.
Do we think this would have an adverse effect on transient response as spl increases as opposed to the untreated dome. If it did how could we overcome the extra mass?

The heavier the cone/dome the greater the voice coil current/magnetic field necessary to move it = more power = more heat.

Assuming adequate gap flux and voltage drive it is winding resistance which limits maximum drive force at lower frequencies, though additional series winding inductance impedance at higher frequencies.

With current drive the voice coil impedance is much less relevent, but then cannot accelerate a heavy dome as quickly as does voltage drive. This is because back-EMF does not reduce voltage drive current development until after the voice coil has moved, whilst with current drive the current is not back-EMF dependent.

So given that current drive is not common, cone/dome mass is important at HF because voice coil inductance and thermal efficiency becomes the limiting factors in a way which cannot be overcome, so it is the moving mass which must be reduced.

These being reasons why tweeter voice coils are smaller, lighter, of lower inductance and coupled to light cones and domes.

Attach a tweeter voice coil to a dome plus cone and you get - a widerange Fostex etc.

Cheers ..... Graham.

[John Kalinowski]

Post should read the the case against any driver not selected by Ed for horn shops. Still think the Cow dirt bikes your best work. Maybe large 70s super bikes converted to dirt bikes a unexplored market. Screw this self promotion of wee little toys. Time to move onto the much more manly field of vintage street bike to dirt bike conversions. Cant wait for discovery channel to pick it up. Should be heck of a lot of fun to watch. But I digress Since your a manufacturer Ed maybe you can find someone to manufacture your dream 10g 6in tweeter since Ive never seen one maybe you right it shouldn't exist unless like your Cow dirt bike it really needs to exist. 

[Ed Schilling]

John,
 Your lack of understanding and comprehension has just been demonstrated again.

This is the wrong thread and I'm not done here. This one is about mms and single drivers. I ran out of time due to actually having a couple pair to go out and have not returned yet.

You'd not last a minute on my Kawa, BTW. I drag raced that bike for years and if you think the genre of 100 hp "cow bikes" as you call it is a common thing, so what? My best work? Who said that?  And you completely missed the point, which does not surprise me. In that post I was making the case for anything you want to build, for anyone.. I did not say who "the guy" or "the know it all" was.

Get a life.  And keep going buddy.......I'll be happy to entertain you with replies to your ridiculous attempts to dismiss my opinion and success.



And John, anybody can stick a couple fancy drivers in a box and call it a "system". I could truly give a rats ass what you do or say.....but that doesn't mean I won't use the opportunity you provide to respond to your nonsense.

You see, I know exactly how effective my speaker is.......you on the other hand have not a clue, and your "experiments and failures" are not a reflection on the driver I use. You said something like "getting out of the market for those speakers because there are so many".

Well, if you built something that was unique and not the SOS that others do you might build a good 126 based speaker. The market may be crowded but guess what, even if it were empty it would not matter. For you and similar designs. Just because "fostex recommends it" doesn't mean it's actually good.

And Yes, John, if people are paying attention they already know I do in fact have one of if not the most successful single driver speaker of a practical size you can buy. Stereophile ranked and a recommended component, now that may not mean much to you but then, who gives a shit what you think?  Certainly not me.

And anyone could learn from what I say and do, to build something "similar".........instead of the same old flawed BS like you and some others make. Hey, it's the truth and you brought it up.

I should also warn you, I am a "nice guy".....but when confronted with hostility from "guys like you", you'll find I'm "not so nice". Not that that should bother or "scare you" but rather.......don't be surprised when I start "not being nice".

But hey the ball's in your court.....have at it. Every now and again guys like you pop up......been dealing with it for years. You'll learn sooner or later this was all a bad idea. I  am going to remove the plug I gave you. You lost your advertisement for being an ass 
I'm sure you didn't need a plug from me anyway. What was I thinking?

BTW.....I NEVER said I own the only "stupid bike".....or was the first or only to do it, put on your "comprehension cap" and read that post again. But thanks for showing your ass. In the wrong thread.

And please, spend some time to actually format your replies and get the spelling and grammar correct so I can understand what you are saying. We are not in grammar school. We should write like we passed.

"My" dream 6 inch tweeter? WTF? It is the case AGAINST one I will make, eventually.

Ed

[sts9fan]

I would think by your explanation that a 4" would still make a shitty HF driver.

[miklorsmith]

 

Ed - I think this thread should be in your circle, not SD.  Your message has a commercial, promotional bent whether intended or not.

[doug s.]

I would think by your explanation that a 4" would still make a shitty HF driver.

i agree.  but we all know ed is getting at the fact that he feels, due to all the compromises inwolwed, a 4(.5?)" fr driver makes the best single-driver compromise cuz it will do hf better...

ed, you should look into the parts express driver recently touted elsewhere on this site - it's even smaller than the fostex 126 - tho called a 4" driver, it is in fact only 3.04", which includes the surround; cone itself looks to be ~2.5".  yes, it's much less efficient - about 10db less.  but it has twice the power handling, so that gives you back another 3db.  now, it may not work in your standard horn, but how about your "model 2"?     i know you have seen this - you posted to the thread...  now, i know that a "model 2 type" iteration w/this driver won't play as loud as even your standard horn, but it seems it will play >100db continuous, w/peaks even higher, when all is said & done...

http://www.parts-express.com/pdf/295-358s.pdf


re: bikes, i like the kaw litre bike idea, but i like this better.  of course, it costs a bit more coin...   


but, being a street-bike kinda guy, i really like this one even better!   


best,

doug s.

[Ed Schilling]

Sts,
Still short for time. Most do! Graham's post is "getting there". But you are thinking......good.

Msmith,
Sorry about that, you may be correct but it certainly was not the intent. An "good" diy'er should be able to get that it is the opinion of a person who has "done it" that there is only ONE WAY to get high spls with a small single driver and only ONE WAY to shrink the mouth of a horn. This is not an unimportant thing.

And a "good" diyer" may actually use this concept to make something that reinforces my opinion and method.

Doug,
That is the spirit! I looked at that driver...mms is 3.9 grams (I called PE) and with the small cone and phase plug it does not have enough surface or efficiency for the SPL's I require.....not even 4 of them. BUT......it may very well be used to make a FANTASTIC sounding system within it's abilities. It will require some experimentation from the diy world to know how it turns out. You appear to get my "hints". Good. Thanks.

Those are nice bikes.....the "super motard" is a GREAT idea! My XR is not big or fast enough for the concept and without knobs it is dangerous. I'm stuck using it for it's intended purpose. The Kaw is just ridiculous.

My point of that analogy was "do what you want people, regardless of who thinks it a good idea. If it works for you then great, but don't say something is impossible because you have not experienced it".

Anyway......I'm super busy and I am going to finish the point of the thread later........

But in the mean time......does ANYONE think that using a pair of KHorns "near field" and not in corners will "sound good"? Or have the extension or efficiency they do when properly placed? Would ANYONE compare KHorns used that way to a pair of La Scalas? They have the same drivers and x overs (for all practical purposes) after all.

But yet....the 126 in an improper (most all) "BLH" is being compared to a "corner horn" and then the driver in both is said to not be able to "play loudly" as it were. It is NOT my fault that so many improper loading schemes exist. Or that people insist on forming opinions of drivers based on bad designs. I have TRIED to tell you how to do it.

Just asking, and begging....read between the lines.

Ed

[jrebman]

Ok everybody, time for me to put on the facilitator's hat and ask everybody to take a deep breath and chill for a bit.

First, I know Ed better and he's not here to plug the Horns -- they don't need that.  If anything he's here to put in a plug for hornloading, specifically BLHs (done properly) for a particular purpose, and as such I welcome the technical nature of the discussion in this circle.

John K.  the following:

Post should read the the case against any driver not selected by Ed for horn shops.
Still think the Cow dirt bikes your best work.

Was completely uncalled for but as you're new here I'll let it slide for now and assume you're used to the AA/ Audiogon world where that kind of cheap shot is the rule rather than the exception.

People, it would help if you could draw a distinction between the Horn (upper case H) and horn (lower case H).

And Ed, I have some idea of where you're going with all this and I do appreciate fomenting the technical discussion, but let me be the bad guy here, ok?

Now can we get back to the polite, non-personal technical discussion here?

Thanks,

Jim the reluctant cop.

[Graham Maynard]

My point of that analogy was "do what you want people, regardless of who thinks it a good idea. If it works for you then great, but don't say something is impossible because you have not experienced it".

So Ed - I'm smiling, and wonder where you are taking this thread ???
(Sounds like you'd love the new VMAX, but that's not perfect either.)

And isn't that the point - getting the best for oneself, knowing that 'The Best' will always be evaluated to somebody else's standards !

Cheers .......... Graham.

[John Kalinowski]

Ed as always a real pleasure to deal with you. A true professional..You sure get away with alot in this forum. But I will say this to your many insults to me. I quoted you before you outright lie about me. You totally shill your produce even if it means folks get wrong info from you. What do you care if their are happy you got the money. You are not honest about your opinions all are biased towards your product. I am a true loudspeaker designer I could care less what someone of your skill and experience level thinks of my products that you've never seen or heard unlike I yours but still you offer opinion on my work? Again a post by you on something you have no knowledge or experience about but will further in your mind sales for HS. You just build 1 BLH loudspeaker. I  have much experience with the drivers I mention and in many different designs. You just want to make a sale and I try to be honest. And Ed I road raced motorcycles owner near 30 Plus I custom build. I can handle any motorcycle on earth. Again you post about things you have no knowledge about seems to be what you do over and over. Post without thought knowledge skills.Just shills.  So to you and AC I say you guys don't value real experience just looking for folks to agree with what your doing. So many posts in forums from folks who have no clue like old Ed. But sure it will become fact. And if Ed thinks his old cows the bomb maybe that should tell you about his mind set. Do something wrong say its great till folks agree. Bye last post...

[Ed Schilling]

John,
You mistook my "and none of your designs are corner loaded are they" as an insult when in fact it was just to show we were not talking of the same thing. Which in this case I was correct.

You have no idea about me, but I on the other hand do know a lot about you. Why do you think I made the analogy and showed the Bike? And made the jab? You think that was by accident? You really have no idea about me.

You are a "real designer"? by whose definition, yours? I'm not, by whose definition, yours? I just don't care to make the type things you do. And I turn down requests all the time.....and sometimes they may even come to you for an expensive "better" speaker, since I WON'T build that stuff.

In the movie "Quigley Down Under"  at the beginning he tells the bad guy "pistols? I don't have a use for them" At the end when he kills the bad guy in a gun fight he tells the guy as he is dying......"I said, I didn't have a use for them, NOT that I didn't know how to use one."

 You should remember that. People don't always talk or brag about what they really can do. Your perception of my postings are not reality. I post in manners that I hope makes people think rather than tell them what to do.

John, My customers all have ears. They make their own minds up.

You still don't get it.....let me try again....horn loading increases efficiency, corner loading can reduce the size of the mouth, and placing a speaker in a corner will cause an increase in overall output. By using the techniques you can make a 126 do things it can't in another cabinet. Such as producing an image like I posted. That was a peak.....average was around 100db.

John, I don't think I questioned your design skills or systems and I even TRIED to give you a plug for the "spiders".

You on the other hand have insulted both me and my customers.............which is fine.

By saying......."sure you can get those spls ED gets but at high volume I found the 126 forced" you opened the door to be corrected.
And again, you have NOT said you tried "my methods". And as such are talking from a point of ignorance, regardless of how many systems you have "designed".

Everything I have said is being proved and tested everyday.

And John, I have been designing loudspeakers for 35 years.....I have built 60 inch ribbons from scratch.....Heil air motion transformers from scratch, including diaphragms before I bought them from Heil.

I can easily build anything I want or can dream up. But there is no need. I care about "practicality".

If I were to offer a free pair of AG Trios to everyone on this board with the caveat that they can not sell or give them away but must USE them I can safely bet at least half the people could not have them just because they are too large and therefore impractical. So would they be "the best" for those people? I think not.

It was YOUR mistaken statement that started this mess, not mine....." if I said the d28af tweeter can not handle any power" and posted it and you used the driver you would think "wtf" and then if I said I like to cross it over at 250 hz, I am pretty sure you would like to point out I was certainly able to use it that way but it will in fact handle GOBS of power when x overed at 1.5K.

Can you see that? That is what you did and when questioned/challenged you took it personally, insulted me and my customers and called me "shilling" (now THAT, my friends, is funny, and I worked hard to get it in).

You have disappointed me however.....I tried very hard to give you an analogy that you'd appreciate ( I knew of your bike stuff from way back) and again instead of "playing with me" you somehow figured you'd insult me some more. Good job.

And NOW you come back and insult all the AC members and posters. Do you realize what you have done? And do you realize I am right on all I have said? I hope not.

Ed

[Ed Schilling]

Graham,
We'll get there.............and to that end......so, as we increase the mass of our "tweeter vc hooked to a big cone, which makes a wide band tweeter" the result is more generated heat as opposed to a cone that say was identical in all respects but half the weight?

Another question.....what are the 2 main purposes of "magnetic fluid" in the gap of a tweeter? And how does it "work"?


And isn't that the point - getting the best for oneself, knowing that 'The Best' will always be evaluated to somebody else's standards !



We are in agreement. Unless we are talking about measured specifications......10K response is in fact worse than 15K for instance, but some may not hear to anywhere near 15K, so again....your statement applies!

Ed

[planet10]

Does anyone know the Mms of the 7" Hartlry tweeter?

if I said the d28af tweeter ... cross it over at 250 hz,

I've been playin g with the FF85keN and it can rival many a big buck dome & can be used with a 250 Hz XO.

dave

[Graham Maynard]

......so, as we increase the mass of our "tweeter vc hooked to a big cone, which makes a wide band tweeter" the result is more generated heat as opposed to a cone that say was identical in all respects but half the weight?

Yes a greater 'mms' will generate more heat but we mustn't choose a large size/mass voice coil if we want high frequency AF, because it would not then be a proper tweeter.
I guess this comes down to driver design. 
We can use a decent magnet with pole cooling to overcome some heating, though some use fluid to increase ratings.

Also is cone mass the same as 'mms' at HF ??? for this is where much of Ted Jordan's life work has been concentrated.

Anyone ever measure how 'mms' changes with frequency ?

Cheers ........ Graham.

[Russell Dawkins]

Interesting question, Graham. I presume you are talking about effective moving mass, i.e., taking the progressive de-coupling of the driving (central) part of the cone from the driven, you might say.

I was just reading a comment from a designer of a respected speaker how his 15" model actually sounded better in the mids than his 12" and, I think, 10". He attributed this to "better" (which I read as "more fortuitous") de-coupling of the middle part of the cone.

This leads me to wonder about how this would affect the radiation pattern. Does this mean that such a 15" driver would not beam like most and would have the dispersion of the 5" or 6" driver it is presumably emulating?

[Ed Schilling]

For consideration...............

http://www.ejjordan.co.uk/basics.html

I am liking the questions so far.

Dave, don't doubt it a bit. So does a Bandor (which will play to a 100hz easily)...and a lot of others, now, name the 6 incher that "rivals a big buck tweeter"? Not a trick question, but rather "for real". I want opinions! It's "nice" we are in "agreeance" (I love that fake word).

Ed

[Graham Maynard]

Hi Russel,

Yes effective moving mass, plus effective drive impedance which combines amplifier, voice coil impedance and magnetic circuit variation with frequency.

The radiation pattern would be separately modified by cone material, shape, size and baffle etc.

Surely the problem with a large diameter tweeter is the shift of acoustic centre with frequency - it tends towards the dust-cap with increasing frequency - which introduces phase change with frequency and then at some frequencies parasitic reinforcement/cancellation of resultant propagation.

How's this for an 8" diameter tweeter.  Not finalised.  The dust cap protrudes conically by 65mm from voice coil former to optimise the shift of acoustic centre, and the HF *sounds* much more correctly extended as a result.
 
Click on thumbnail and click on opened image to enlarge.

The driver is a B200 with underhung voice coil.  Not supertweeter capable though.

I recon this could be usefully tried on a small Fostex FR too.

Cheers ....... Graham.