The 'sound' of metal cone drivers

[nodiak]

I am really grateful for finding this forum because of the level of development Jon puts into the systems. It's so refreshing and surprising to find these ideas shared freely. Thanks alot Jon.
I find myself hesitating because I've never used metal drivers so I wonder if anyone who has had the NatalieP's could help me out with a general comparison to a similar size mtm or 2 way speaker system that uses non metal midwoofers.
I'm used to the "forgiveness" of paper/poly cones, but open to more detail, just don't want to go too analytical where things get cold sounding. The Scanspeak 18w8543 has been a driver I've had around for years. Great openness, good detail, great power handling, but pretty soft sound when it comes down to it (but I do like them much more than Vifa P17's for example). As you can tell I haven't tried any new/advanced drivers for awhile. I've heard alot of the common diy paper and poly drivers over the last 20 years, so any Seas, Vifa, Peerless, etc. comparison will help give me a clue.
I haven't seen much of this type of comparison, maybe because it gets bogged down in opinions, understandable. If it's frowned upon sorry to bring it up - but someone can PM me . Jon/Thomas, I'm not trying to bog down the thread, if this request doesn't fit the program I would not be offended if it's deleted.
The power handling and frequency range of the NP's should work well for me, I have a medium size room (~ 300 sf.). Eventually I'll add a sub system.
My simple 2 channel gear: Gainclone integrated (LM3875 chip), Audiosector nos dac, Sony NC685V 5 disc as changer (the weak link). Also a very interesting "iMod" - modified iPod by Red Wine Audio which I havent started using yet. I've tried a few preamps, some of the tubed units were nice (Minimax, Decware) but am going without a pre until a sub gets added later on.
I'm sure someone knows where I'm coming from about speaker/driver "sound" and can offer a little diy audio comradery to help me see the light.
Thanks, Don

[ThomasW]

Having started off some 35yrs ago with pulp cones, then moved to poly, next exotic plastics, and finally metal, here's my take....

IMO, of the materials currently used to make dynamic drivers, metal cone units are inherently the most 'transparent'. Now that doesn't mean they're without a sonic signature, it just means their signature is less intrusive in the accurate reproduction of sound than the other available cone materials.

Now I'm a big fan of planar loudspeakers. Daily, I listen to both electrostatic and magnetic planar designs. To my ears, they are the most 'transparent' of all loudspeaker designs. As a result they're the benchmark to which I compare all other transducers. Metal cone drivers, when used within a passband where their operation is most 'pistonic/linear', are the closest to what I hear when listening to the planars.

Now I'm sure someday someone will come up with something even better than the current metal cones. But until that occurs, I'll use metal cone drivers whenever and where ever possible.

[TacoD]

I've experience with both the scan 8543 and Vifa you mention, and I agree that the scanspeak is a more open sounding driver compared to the Vifa. In my opinion, however, the scanspeak does not cut it against the newer products (both metal and non-metal) in terms of colouration (distortion) and bass performance. The soft cone does not allow for proper reproduction of the bass lines (subjective: lack of bass).

Modern metal cones from e.g. Seas and Dayton or ceramic (alu oxide from Thiel en Partner) perform better on almost every aspect, both measurement wise and from subjective listening. A proper designed speaker with metal cones does not sound harsh, metallic or cold. Unfortunate not a lot of people design a proper speaker with metal cones in the midbass department. A lot of DIY designs suffer from to shallow filter slopes, high XO points and total lack of notches on the fundamental break up resonances.

In Jon's designs these problems are addressed properly, therefore yielding an high quality loudspeaker.

But not only metal cones (or DIY designs with metal cones) have improved, also drivers utilizing (treated) paper (scanspeak, peerless exclusive, seas nextel) or (mineral filled) polypropylene (amongst others Audiotechnology) or kevlar cones have improved.

I don't want to give the impression that metal is the only way, within in the boundary conditions of your design (price, XO compexity, taste, experience, skill) with both types of drivers very good quality loudspeakers can be made. Therefore recognision of a proper design consists of more then only comparison of the used cone material.

[cjd]

I think you're really asking about the *lack* of sound... "forgiving" also means "making its own contributions to the output"

C

[nodiak]

ThomasW, "metal cone units are inherently the most transparent" . That's good to hear, and I can relate to the evolution of cone materials. Also I've been trying different dipole/"OB" drivers over the past year and so can somewhat relate to the magnetic planar speakers, in terms of openness of unboxed rearwave at least.
My interest in Jon's designs innitially was because of the xo work that considers driver distortion and polar response. The OB designs I've been trying (single drivers and coaxials) weren't very concerned with those principles for the most part. I haven't tried Nao's or Linkwitz's or Arvo's, which seem very refined along strong design principles tho.
For the next several months I won't have as much time to continue to explore dipole systems. I can live with the NP's as long as I can tune the bass to my room, and I'll learn alot from the design and drivers. They should also be a good step for me as...
...I realize Jon is into dipoles (Arvos), and there has been mention of the NP's being modded for dipole use at some point (I will patient wait for that possibility to unfold).
I guess for me this thread mostly addresses choosing drivers less for their euphonics (coloration/forgiveness...) and more for their technology, like the other components in the chain. I still need to do some work on room treatment too...
It's all an exploration.
TacoD, I agree of course about the whole mattering more than individual parts. But there is an inherent differnce in metal cone drivers vs. paper/poly from what I hear said. Just wondering what differences anyone heard when they "made the switch".
Sounds like I should expect a more neutral speaker with RS drivers. Time to get my euphoinic fix more from the music instead of the equipment!
Thanks for responses, Don
Don

[Jed]

Time to get my euphoinic fix more from the music instead of the equipment!
Thanks for responses, Don
Don

Unfortunately with some of today's recordings, they are so bad that on a highly accurate/transparent speaker and system... well it sounds horrible. The sound engineers must realize that the majority of folks are playing music through ipods and junky speakers, therefore boosting the high end and midbass. Even artists like Sarah McLachlan, I find on a good speaker her voice is whispy and scratchy (because of the recording style), but on a warm midfi speaker, quite tolerable. HiFi can be very frustrating due to the lack of quality recordings.

Jed

[nodiak]

...but we're into nice equipment anyway... 8)
Jed, you've heard alot of speakers, some of Roman's iirc. Do you think the RS metal cones are too revealing for the typical recording?
Don

[cjd]

What genre of music?

A lot of rock is mastered to sound good on crappy speakers. Not all though.

I have two RS projects in the house, and I have yet to find any albums that they cause problems with. There are a couple albums that many people might not like, but they probably don't listen to live music much.

C

[nodiak]

Maybe someone can compare the Scanspeak 9300 tweeters I use to the RS28A-4 (which is back ordered at PE , :M - anyone have a used pair to sell?) . I've always liked the 9300's as they don't have too much air, but lots of detail. As the RS28A-4's have been said to be low on air ( : ) , maybe they sound somewhat similar?
I just took a few weeks off from listening to music. Started playing my system again today. It sounds pretty good, the electronics are clear and have good soundstage, good atmoshere/ambience. The current speakers are a Vifa M22 in vented cab for bass, and a thrown together dipole - Vifa P21's with the 9300's. (xo is from 8543/9300 two way, I just needed something to play as last pair of speakers was recently sold.) FR isn't great, dip in the mids, but listenable.
I think the NP's may have similar F3, and I expect the mids to be clearer and more lively/forward. Guess I'm about ready to take the plunge for the NP's.
Don

[jdybnis]

Here is something interesting. It shows that everything called polypropylene is not the same. This here is the response of a custom driver Troels Gravesen commissioned from Audio Technology. Per Skaaning (Audio Technology) only builds poly cone drivers.



The cone breakup doesn't look damped to me. I'm guessing that the material in this particular cone is not the typical lossy polypropylene.

[cjd]

I'd say still damped a little, but more likely a composite not a pure poly. I've heard poly cone speakers that had definite need of better breakup handling (commercial stuff).

C

[Jed]

...but we're into nice equipment anyway... 8)
Jed, you've heard alot of speakers, some of Roman's iirc. Do you think the RS metal cones are too revealing for the typical recording?
Don

Well, I'm not experienced enough to make that assessment. However, I will say this.. one can find RS woofers in my current 3-way, which uses RS225, Peerless 881, and Accuton C12. Also, a person with enough crossover skill can make the metal cones suit his/her tastes. For example, introducing a bit of a BBC dip can take some of the edge off what was once perceived an overly bright speaker. Power response is very important and choice of crossover frequency and slope can not be overemphasized. I've spent 2-4 hours every day for a month or so tweaking my current 3way to the point where I now find them acceptable for a wide variety of music. Since these lower distortion drivers are transparent they show you where you are going wrong but also really reward you when you get it right. I would have spent a lot more time tweaking some of my previous designs had I known what I know now. But that's half the fun of DIY. Hopefully we learn from our past mistakes.

I've got some Accuton C88s coming this week for me to try in place of the 881s- just for fun of course. As for some of the paper designs I've heard from the standard SEAS line- they can make nice music, but once you hear the resolution of some other drivers, they can leave you wanting more. Pardon me if I sound a bit vague, it's just there are so many variables to the creation of a dynamic and involving speaker, such that reducing the final mix of variables to cone material is just in essence one part of the final recipe. That said there may be certain trends of design that designers live by and there is nothing wrong with that.

Jed