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I am a relative newbie when it comes to DIY speaker projects. I could use some input from those with more experience, particularly when it comes to the various FR drivers now available.
Is is a fair characterization to say that all drivers with a wizzer cone will tend to shout? I have heard Lowthers and tend not to like them for this reason. Do the Fostex and others like the Hemp Acoustics drivers, which both have wizzers, do the same?
Thank you for your reply
I think the problem is that "shout" is not a precise term.
Whizzers have several effects, and it's unclear which of them - or which combination of them - is called "shout". Here are the ones I am aware of:
1) high frequency emphasis. Increasing the treble energy is the point of a whizzer, of course, but in many cases it provides excessive high frequency energy. IIRC, Lowthers do this in the 2kHz to 10kHz range, often averaging 10dB emphasis on axis. Beaming mitigates this, depending on the room - one reason (IMHO of course) some of the more complex Lowther cabinets have some drivers pointing away from the listener. A large horn will boost the lower frequencies to bring the spectrtum into better balance. Also, see intem 3).
2) ragged frequency response. The whizzer is unterminated, so its resonances are not as well damped as the main cone. The perceived effect depends on the music, and on the distortions in the rest of the chain - there is a lot of mutual masking going on, IMHO. The best of the non-whizzer fullranges avoid this problem, but still suffer the others.
3) beaming. Any large driver will beam, and the whizzers are often 3"-4" diameter. To me, this gives an unnatural sensation - bright and dull at the same time. The treble emphasis on-axis is balanced against the weakness in the reverberant field, but to me it never sounds quite "right".
4) distortion. Any time you use a fullrange driver, the bass excursion nonlinearities will intermodulate with the high treble. High efficiency drivers with small excursion capability make it worse.
Any of these, or any combination of them, might be called "shout" by someone. All of them have solutions that can at least mitigate the problem. Sorry to say, it is never going to be as simple as "whizzers shout, so I'll use something else". All the alternatives have their own problems and their own, more or less partial, solutions.
In any brand name driver.
Wizzers add mass but also extend the high frequency response of a cone driver, so I think there's more to it than just power-to-weight ratio.
My understanding is that a wizzer cone's smaller diameter and steeper profile make it much more rigid than the main cone. So when the main cone is effectively de-coupled from the voice coil due to cone flexing at high frequencies, the wizzer remains rigid and couples well to the voice coil and to the air.
In fact, the high mass of the whizzer cone does not allow it to move as an entity at high frequencies, even though it is relatively rigid. Instead, it goes into multiple breakup modes. With proper material, breakup resonances can be dampened, which allows achieving more or less flat frequency response. But don't be misled by flat response. Distortion and stored energy tests of whizzer cones are uniformly unfavorable.
It doesn't take sophisticated tests to tell the difference between a whizzer cone and a dome tweeter. With demanding acoustic material like vocals, piano, and strings, it is very apparent.
It's quite possible that I'm incorrect about the wizzer remaining rigid. It probably starts out that way, then goes into breakup but at a much higher frequency than the main cone. I can imagine the unterminated edge of a wizzer cone causing problems. Some of the better designs put a curl in the edge which probably introduces some much-needed stiffness there.
So far I haven't seen any distortion or stored energy tests on wizzer cones (nor much on other cones for that matter) - do you have any links?
In my experience with fullrange drivers, "shout" can be tamed by equalization. There are other issues which cannot.
John Krutke's site (Zaph Audio) has tons of info on driver distortion. Unfortunately, none of the drivers he tested were hi eff. His objective measurements provoked ire of some manufacturers, if I remember correctly.
Manufacturers tend to publish distortion data only if there is something to brag about. I remember I was impressed by distortion figures of EV DL-12, or waterfall plots of BG Neo drivers, and indeed these drivers sounded good.
that I couldn't find any distortion or waterfall plot for a whizzer cone drivers on the internet.
I remember reading an article by a former car speaker designer who used whizzer cones to add brightness to one-driver speakers. He said that an average consumer would percieve it as top end detail with kinds of music that people usually listen to in a car. Mesurements showed, however, high levels of high frequency distortion.
I think "shout" is a frequency response issue, not necessarily a wizzer cone issue. It can be tamed by taming the frequency response, whether or not the offending driver has a wizzer.
Not all drivers with wizzer shout, what the wizzer does is a ragged high frequency, like some haze around mid highs, I lived happily with lowthers for about 2 years until something clicked in my head and I started hearing the wizzers and it was anoying, disconnected my whole set-up and now I am using horns.
Lowther give out much more detail and are more dynamic than Fostex, Fostex are very sweet sounding and have nice detail, If you dont A-B Fostex is wonderful, If your are sensitive and like a relaxed sound go Fostex, If you dont want to fight in order to make the Lowthers sing, go Fostex...Better yet get vintage Sabas, they are almost in the middle of Lowther and Fostex, IMHO...
Not all drivers with whizzers shout.
My Fostex drivers with whizzers don't shout. Ditto my Hemptone. Or my big Goodmans Axiom 201. They also don't have the aliveness of a Lowther either.
Having said that... I once cut off the whizzers on my DX55 Lowthers and it removed the shout. It also removed a large part of the highs/aliveness. But, it made for an excellent transition to a tweeter... as do some other less expensive drivers- so perhaps a failed experiment.
Only my Feastrex D5nf has the aliveness of the Lowther without the shout. However, they not perfect either. Like most small "fullrangers" they are challenged with large scale macro dynamics and frequency extremes (all fullrangers). And unfortunately they are also the most expensive.
Some people say the shout is related to the whizzer. Some people say the shout frequency range is well below the operating range of the whizzer so the whizzer can not cause the shout issue.
I recently built some speakers using the Hemp Acoustics FR8 driver. They sounded fine for the first 20 hours or so then they seemed to develop the shout issue. I kept using them though and after about 100 hours the shout faded away. I really enjoy them now.
I have these in a BLH and lovem, no shouting just great musical volcals with depth, warmth and acuracy.
I also happpen to be using them with good amp's...
Fi X SET 2a3 and Dynaco ST70...
Never heard shout in non lowthers, the lowther shout is all lowther;)and the new model lowthers dont have much problem with it.FYI fullranges are availible without wizzers Fostex fe208e sigma -f200a f120a, fx120, fe126e, fe127e, Tangband makes a few, Jordons have no wizzer,nor do PHY,Supravox others about. I perfer fostex drivers over lowther[YMMV] after owning, 2-pm4a new cone, 1 pm4a old cone,1 pair new dx4,heard so many over the years some of my local audio buds have other models of lowther not all DIY one has rethems top model from a few years back.Heard or built most lowther cabinet designs.Lowthers are good but costly and I feel not as advanced as some compition Lowther make pretty much the same product every year,not that this is bad if product is great, but I feel there a sleep at the wheel like the english did back in the 60s late 70s with motorcycles which I enjoy but where far behind hondas of the day.Happy the english are back making motorcycles they based them on kawsaki but to give them credit they moved past this and where smart enofe to know they needed to do so. Fostex engineers at foster bring out exciting new designs almost every year.And for the cost of a set of lowthers one could purchase 2 fostex t500amk2, 2 fe206esr or fe208e sigmas too me a much better sounding combo.
Thank you for the reply. That is helpful. I was concerned that maybe all wizzers cones have this problem. Apparetly not. T
Some Fostex do shout IMO, but I think cab desighn & all that has alot to do with it..so really not fair I suppose to say a absolute on the driver.I use a Calrad 12ae 12" alnico in OB in a bedroom system & it has no shout ....I have had many Fullrangers that have NO wizzer & shout like crazy... like some Saba's...etc..
I respectfully disagree with your Lowther -Fostex comparison (albeit it is based solely on front Azura horn loading )There is simply no comparison between DX4 and 208EZ-(plus EV-T350).I know it is cheaper to build with Fostex and it will sound good but personally I'd take one very good speaker over five just OK. Fostex is very good driver for the money no doubt but substituting it with Lowther makes you forget it the very same minute. Regards, L
My data sets in both cases are small, but the standard error is low in both cases as well :-) I've heard Lowthers sound scary good on choral SACD's (Gregorian chant) but basically unlistenable on highly-processed "pop" music (e.g., Hendrix) on vinyl.
The Fostexes are honest enough, but still keep most things listenable. Since I like to listen to music, not equipment, they seem like a far better real-world value.
I have, and use, a pair of FE-207E's in bass reflex cabinets (built by Bottlehead DaveJ here in Massachusetts).
Here's another nice sounding FR driver with a whizzer...
Nice pictures, cool speakers!
Regarding highly processed pop music (like Hendrix) and Lowthers: it can sound damn good, given the right speaker.
One of the worst ruckuses (ruckii?) I ever heard was Jimi on vinyl on apair of AlNiCo Lowthers in HUGE back horns. Absolutely painful and one-dimensional to boot.
I do believe that Jimi might, on rare occasion, have used some artifical sound-processing stimulation. :-)
A fe208e sigma needs a tweeter where dx4 can be used without my comparison was t500amk2 with fe208esigma to dx4 this is the same price and to me far better performing combo.I much perfer the trebile responce of a proper horn tweeter like fostex t series over any fullrangers trebile responce which to me sounds rough, ragged, lacking in fine details. If you havent heard the new t500 amk2 with fe206esr or fe208e compared to a dx4.Then I dont see how your fe208e with EV would give anywhere near the same results.But when it comes down to it if you enjoy your lowthers thats all that matters.And I have tried many drivers in azuras my best combo at the time was old t500a-t900a used both and f200a [link below ]the f200a is wonderful in front horns like azura and oris but only arround 96db this does make matching horn to bass system much easyer so might be a good thing whole system would run off my 1 300b without biamping.In my azuras and oris I have run lowther pm4a, both style cones,AER, dx4, f200a ,fe206e, fe206esr, fe208e sigmas, beta tested many hemp cones [a few of these are availible in mass market] Moths sure Iam forgeting someone. Take care and happy horn listening
I don't know how to call this type of design operating 6+ octaves and crossing at cutoff frequency with hornloading starting maybe at 400 Hz. Your horn on the link seems small to me to be Azura is it Oris 200?? I don't think I can hear much above 14k so 15k EV-T350 is fine for me. I think the main difference is in tonal quality of Lowther speaker. You're right about wizer cone. Regards. L
Thats a azura 204 not old oris 200, bass horn comes in at 250hz.Bass horns over 8ft might of thrown your size and crossover estimites far off;)
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