Romy the Cat wrote:

If the S2 is completely decoupled (second order low-path at 1.5kz) then the rules of the game completely changed and the S2 behaved VERY different. I will wait until the dedicated channel of my Super Melquiades will be driving the Vitavox S2 driver and then will see where I would be able to take the performance of this driver further. Rgs, Romy the Cat

skushino wrote:

Romy, please elaborate on your experience using a 2nd order crossover.  What do you mean "rules of the game change completely?"  Why did you try the 2nd order?  Are you concerned with damage to the driver with a 1st order crossed-over at 500Hz?  Or something else?  I was thinking of trying a similar approach.

Rgs,
Romy

To whoever loony people who still observe me battle with Vitavox S2 driver I would like to inform abbot my latest events.

Believe me or not but with the Super Melquiades dedicated HF channel I find the internal courage to try the older diaphragms. Again!

With the Super Melquiades HF channel I have much more method in my disposal to deal with the older, metal surround, diaphragms venomousness, and I hope I will be able to deal with it. So far the results are not satisfactory but will see when I will lean with this.

About the objective data: the metal surround diaphragms, as I wrote before are much more sensitive (with the same impedance) primary due to these absents of HF roll-off after the secondary resonance. The exact numbers of the output differences are following:

The new S2’s diaphragms with plastic surround used 40K/10K voltage devider at the Milq’s input but the diaphragms with metal surround demands 47K/8.2K in order to produce the same acoustic pressure. There is no disasters impedance rise in metal surround diaphragm that enables it to work very nicely at upper bass...

Rgs,
The Cat

Hm, I do not know men, but it des not work. Over the last few years I have tried the ordinal metal diaphragm 4 or 5 times and not with the Super Melquiades it is the most successful try but I still feel than it is not the sound that I would like to get.

The metal diaphragm is super fast and super transient, it has phenomenal “absolute tome” but at it higher boundary it has some issues that I newer was able to deal with. I do not know now describe this idiosyncrasy of it’s sound. Previously it was the certain harshness but not with the Super Melquiades’ dedicated channel when the S2 driver does not see the upperbass coil it stopped to be “harshness”. I have to add the amount of the “harshness” is very minor, close to be completely negligible (at least I have no one person beside my who have listened my listened room and who would note it), however it is there. So, with the dedicated Milq this “harshness” became overly nervosa-loaded transient. I think it has something to do with some kind of cone’ resonanses at ultrasonic level, but not too high (20-30kHz like with most metal domes) but at much lower frequency – I would say ~15-20kHz. . This Vitavox S2’s reso-nervosa it sound VERY impressive (in fact impressive like nothing else) but this reso-nervosa at HF is identical across all music. I certainly do not appreciate the last sentiment….

I still like what the fully metal diaphragm does but I doubt that I might use it as is. There are 3 strategic directions that I might take to make it working, if I will be perusing it.

1) I might go for slightly larger horn, perhaps 330Hz that will set the driver deeper and will roll off some HF. I do not partially like this direction as with the deepening of the horn many other problems will pop up.
2) I might try to find some ways to mechanically damp the cone by tinning the back chamber. This is very nice direction to go but it might not be useful and I have issues not with HF knee not with LF knee.
3) I might very slightly to change the mass of the diaphragm, perhaps by spaying it, or painting it, or cover it with the saliva of a pregnant adolescent camel, or you name it. This is certainly the most interesting direction but it is completely unpredictable, not controlled and only God knows where it might lead and what I might end up with. Perhaps Bud might saddest something toward to this end…

Anyhow, will see…
Romy the caT

Romy,

First thing I would try is a single dot of Elmer's White Glue applied in the exact center of the dome, on the outside. The dot would be the size of a round wooden toothpick, cut off at the beginning of the taper. Dipped in the glue, the end of the toothpick will form a bubble of the exact size needed. This stuff is removable, with alcohol as the solvent. The commercial name is Poly Vinyl Acrylic or PVA.

If this addresses most of the problem apply a dot on the inside of the dome in the center. These dots will remain slightly visco-elastic, essentially forever, and will exhibit their final properties after about eight hours drying time. This dot should affect the hemispherical ringing of symmetrical, odd order modes. These are unnatural sounds, mostly providing a hiss to all other natural, asymmetrical sounds that occur within the various frequency ranges that excite the even order symmetrical hiss.

If this is all mostly satisfactory but you notice a slightly latent character to the transients, a small circle of MicroScale Gloss Paint from your local railroad hobby store, applied over the dot and in a radius about 3 to 4 mm around the dot, with a small, fine haired, well drained brush will repair the transients without allowing the symmetrical standing waves to reform. You can also apply a 3 to 4 mm wide band of this stuff on the suspension of the dome, right at the outer perimeter of the free material, before it enters whatever form of clamp is used.

If none of the above works you are doomed. Even my full treatment is not enough to completely remove the metallic scrape that a metal dome can apply to sounds. But, these are the horrid metal domed tweeters found in some inexpensive direct radiator systems... like the ones in my Buick!!!!!

Bud

Bud wrote:

First thing I would try is a single dot of Elmer's White Glue applied in the exact center of the dome, on the outside. The dot would be the size of a round wooden toothpick, cut off at the beginning of the taper. Dipped in the glue, the end of the toothpick will form a bubble of the exact size needed. This stuff is removable, with alcohol as the solvent. The commercial name is Poly Vinyl Acrylic or PVA. If this addresses most of the problem apply a dot on the inside of the dome in the center. These dots will remain slightly visco-elastic, essentially forever, and will exhibit their final properties after about eight hours drying time. This dot should affect the hemispherical ringing of symmetrical, odd order modes. These are unnatural sounds, mostly providing a hiss to all other natural, asymmetrical sounds that occur within the various frequency ranges that excite the even order symmetrical hiss. If this is all mostly satisfactory but you notice a slightly latent character to the transients, a small circle of MicroScale Gloss Paint from your local railroad hobby store, applied over the dot and in a radius about 3 to 4 mm around the dot, with a small, fine haired, well drained brush will repair the transients without allowing the symmetrical standing waves to reform. You can also apply a 3 to 4 mm wide band of this stuff on the suspension of the dome, right at the outer perimeter of the free material, before it enters whatever form of clamp is used. If none of the above works you are doomed. Even my full treatment is not enough to completely remove the metallic scrape that a metal dome can apply to sounds. But, these are the horrid metal domed tweeters found in some inexpensive direct radiator systems... like the ones in my Buick!!!!!

Bud, it is interesting that you mentioned the “horrid metal domed tweeters found in some inexpensive direct radiator systems”. I know exactly what you mean but the sound the produce is quite different then what S2 does. What S2 (with original metal diaphragm) does is even quite different from what those distance-centric titanium-inverted domes do in Utopias and Wilsons. The inverted domes, along with their over 30K resonancees, produce very clean auditable HF but they produce the “harshness of space”, that is quite devastating characteristic of entire sound. The S2 has very different dome, an in addition it a phase-plagued compression driver with own metal suspension:

http://www.goodsoundclub.com/Commerce/SaleImages/S2_Diaphragms.jpg

The S2 metal diaphragm “issues” sounds very different to my ear. It more like a sort of caramel or honey sound that become sweeten with each Hz at geometric progression somewhere above 10kHz and at 12-13kH that arrives with something remotely reminding a spoiled or rusty tone. It has a feeling of late autumn air, filed with the smell of burned tarnished foliage, early freeze and dominating yellowness…

Rgs,
Romy the caT

Romy,

I actually prefer the essence from the other end of summer, that wet, clear water running sound, so exuberant and hopeful ... though autumnal music has its own joys.. you only need encounter Vivaldi's  Four seasons portrayed by N. Marriner and the Academy of St. Martins of the Fields on an early Argo pressing to understand the joys of Autmn 

If you have any friends at Polk Audio you might try to find out what compound they use on their cone drivers. It is a very elastic material and quite sticky, so it might be preferable to the PVA. The MicroScale material is a clear gloss, I forgot to note that earlier.

Bud

Bud wrote:

I actually prefer the essence from the other end of summer, that wet, clear water running sound, so exuberant and hopeful ... though autumnal music has its own joys.. you only need encounter Vivaldi's  Four seasons portrayed by N. Marriner and the Academy of St. Martins of the Fields on an early Argo pressing to understand the joys of Autmn  If you have any friends at Polk Audio you might try to find out what compound they use on their cone drivers. It is a very elastic material and quite sticky, so it might be preferable to the PVA. The MicroScale material is a clear gloss, I forgot to note that earlier.

I know what you want to say by the “other end of summer” - this is why I have two “reference” cartridges: one yellowish another is more blueish. Anyhow, this all usually brings to the infinite chase of  the “better tones” instead of the “getting” the “absolute tone”. I still have a lot of options with the HF’s “polishing” and recently have discovered some promising things…. Will see when were I will be ending.

BTW, I do not see the Vivaldi's  “Four Seasons” as a work that has ANY colors. To me it is a pure B/W work based upon the sequences of contrasts instead of the sequences of the shadows and half-tones. Probably because of this the Marriner with the Academy would not be my first choice, although there are much more color-try to load performances of this work. For my B/W, high optical gamma version I usually go for some radical “smaltzy” play: something like the “Sonatori De La Giolosa Marca” with Giuliano Carmignola or “Eropa Galante” with Fabio Biondi…

Rgs,
Romy

Whoever followed my bothersome experiments in search for a better diaphragm for Vitavox S2 driver knows that I lately spent quite a lot time trying to make the original metal suspension diaphragm to work. There are a LOT of advantages in those diaphragms and a lot of “issues” to use them. In the end, I have to declare my FAILURE to make the vintage metal diaphragms to work with S2 driver in the way, which I would consider acceptable. Because of my certain dissatisfactions with the S2’s metal cone I have returned my playback back the contemporary production plastic surround diaphragm (the way in which I’ve been using the S2 since the beginning: 3uF, 2700Hz electrical, 1000Hz acoustic, 106dB). It is nice to “return home” and learn my all my initial sentiments about the S2 driver are still standing….

Rgs,
Romy the caT

You must be into antiques or something.  Just buy a Raven R1.  It will easily outperform both the EV  (which is not very good) or the Vitavox (which is good if your hearing doesn't extend over 12Khz) tweeters. 

Yago From Yuma

Yago,

I appreciate your suggestions  about what I shell do instead of what I am doing (!). If you feel that you are the only one person in the world who is familiar with the Ravens then you are mistaken. However, I would like to remind you this thread is a collection of the posts about the Vitavox S2 driver (about which you presumably have no credible reasons to talk).  If you wish to start a new thread where you would educate public and me about the Ravens then feel free to do so. Perhaps it might be even educational for yourself… please do not reply in this threads if you post is not Vitavox S2 related.

Rgs,
Romy the Cat

Collin,

I do not remember that I wrote that Trios are “duller”. In fact I do not remember I ever wrote anything about Trios in comparing to my current hors. Furthermore, my “Macondo” derived for the Trios and practically fully inherited the Trio’s upper bass horn (with some advancements that overcome the Trio’s  upperbass horn limitations). Also, Trios do not have “high compression ratio or very slowly expanding line”.  Trios run regular tractrix curves and have very low compression, practically none, as they do not use compression drivers and do not damp the cones with back chamber. Sorry, I really do not know what you are asking and how it relates to Vitavox S2 driver (the subject of the thread).

Rgs,
Romy the Cat

morespeakers wrote:

If there is any info in this or another post about why the S2 is so much better than the Altec 288c please direct me. If not what makes the S2 drivers so different than a 288C? (I am talking about 288'cs that the 24 ohm diaphragms have been replaced with newer Altec aluminum lower impedance diaphragms which I would imagine by now almost every 288 c has undergone) Both drivers seem to have a very similar looking phase plug looking from the back. Stock diaphragms seem similar too. By the  way my main system has 288c's on 500hz round tractrix poplar wood horn at the moment but always willing to try something different.

I do not know other people who use the Vitavox S2, as least who get any results with S2 that I would consider worth attention.  As far as I know I am the only one “public” person who spared noise/rumors about the “unique” S2 Sound. There is “Unofficial Vitavox Web site” and the folks in there heard something about this driver but it pretty much it on internet. If someone uses the S2 driver advancely then, they have no internet presents.

The S2 vs. 288. This is complicated. To me all Altec are slow, not contrasty and decolorized. They have the “nobility of the tone”, that royal tone of the Prague or Vienna Philharmonics… or that lush wet bass tone of the period instruments. The larger Altec do have some size of the lover frequency harmonics but I doubt that it might be useable in context of 500Hz.

Still, my assessment the S2 might be slightly not objective as I juts have nothing else to like among the compression drives and as a result, I picked the S2 because I hate it mush less then many other drivers. In fact I do not really hate it but rather love it. Still, it does not prevent me clearly see some “issues” with S2 driver. This is why I keep working with it.

http://www.goodsoundclub.com/TreeItem.aspx?postID=1929

Rgs,
Romy the cat

jweiss wrote:

When we spoke at CES, you mentioned that your experience with field coil drivers only extended to cone types. So I assume that you have never heard any field coil compression drivers. That would include the WE 555, 594, RCA 1428, Lansing, etc? Also, I would assume you never heard the later RCA compression drivers either?

Yes, it is correct. I never dealt with compression electromagnetic drivers but only direct radiation cones. Also, the electromagnetic that I did use (Telefunken, Klangfilm, Magnavox, Jensen and a few smaller brands) from my point of view were not very good drivers themselves, regardless the type of the magnet, and therefore of judge from them the befits of shortcoming of the field coil as a concept is imposable. My experiments were around running my electromagnetic drivers high-passed and band bass in open baffle and loaded into my older uppers bass horns. Still, I have my reasons to believe that I would not appreciate the WE 555 and the Altec’s field coil version of 288 as some of people who have them, use them and well familiar with their sound gave me quite detail reference points about their sound. I never heard the RCA’s compression drivers.

jweiss wrote:

Maybe you might want to listen to some of these instead of all the modifications you have either tried or envisioned for your Vitavox S2's?

I always interested to heard new compression drivers, no doubt that if I have them than I would give them a try. Still, I have my “issues” against a blind using of 70-50 years old sound producing devises. In my experience the vintage technologies “as is” never work reasonably well. I have the absolute firm conviction (based upon reasons and facts) that the “vintage” drivers, as they were designed, will not work well in the context of the contemporary higher demand playback. Anyhow, my experiments around Vitavox S2 have dual propose. First off all it will be “clean experiment” that would allow to easy subtract the contribution of the field coil to the sound of the driver. Second, I like the sound of this driver and I know it very-very-very well. There are some shortcoming in this sound as well and I, clearly recognizing them, would like to learn if by the means of field coil would be possible to overcome them – without loosing ANYTHING else. However, I have to tell you that for the last week the electricity in Boston turn out to be absolutely wonderful and what the S2 does recently is juts phenomenal. There are no signs of the “issues with S2” that I observed before and if the S2 would sound like this all year long that I might not have any reasons to experiment with field coils. Well… probably I still would, as there are two more redesign objectives (change the tape rate end fix the pre-gap edge problem) of mine that would be juts much simpler to implement with field coil.

jweiss wrote:

It would also certainly give you some points of comparison to the Cogent drivers which you initially liked. I know you took notice of the threads, such as Mr. Geddes, as to what exactly were the relevant design variables in these drivers that accounted for the current interest.

Jonathan, I do not know if the Cogent are the “electromagnetic drivers”. Whatever they are they are Cogent own drivers with this own sound (like any other driver). How much in Cogent comes from the electromagnetic and how much came form hundreds other design decision that Cogent is made off is unknown to me. I perceive the Cogent and self-contain completed driver with own set of positive and negative sonic signatures. But I do not see Cogent as some kind of prove or disprove of the electromagnetic concept. If I heard the Cogent with a good, old, fully charged Alnico magnet instead of the field coil and then the field coil version then, (and preferably in reasonable horn) I would be able to say where was the Sound of the Cogent driver itself and where was the field coil contribution. I do not have this experiences and the only what I can see is the complete sound of Cogent.

Judging the Cogent’s driver “as is” I find that Vitavox S2 is way more interesting sounding, and therefore  I feel the S2 much more fruitfully ground for my further experiments. I do not feel that at this point would be worth to write any Cogent vs. Vitavox S2 evaluation. Perhaps you should do it. Anyhow, I am not juts bravado about "my driver", and I am very comfortable with presenting the actual results that would justify my words. You are 4 hours away and you welcome to stop by and make you own judgment. It would be also fun if you bring the Cogent MF drivers along. I am pretty sure that I would be able with a couple hours to plug them in. Well, I feel that if you heard a properly applied Vitavox S2 then you would hardly be interested to replace it with anything out there (I am not taking about the ownership paranoia but about the actual sound of the driver, nothing else)

Still, I’m leaving all cards on the table….

cv wrote:

Allo I had a theory that the bug screen was helping to damp horn modes/refelctions caused by a mismatch between the S2 internal flare and the horn flare rate. I have 340Hz flare JMLC horns, which may be expected to give less of a mismatch than the smaller tractrix units Romy is using. So I removed a screen yesterday. Only had time to listen briefly; there was more treble but now what sounded like like a resonance at a few kHZ that kicked in on strings, flute etc and made them, well, almost sqwawk and hiccup... Anyone know what the internal flare rate of the S2 is? Martin Seddon is making me some 160Hz horns with 1.5" throat for a different application. Don't intend to use them with the S2 but would be an interesting experiment to see if the above behaviour is reduced.

So I removed a screen yesterday. Only had time to listen briefly; there was more treble but now what sounded like like a resonance at a few kHZ that kicked in on strings, flute etc and made them, well, almost sqwawk and hiccup...

Anyone know what the internal flare rate of the S2 is? Martin Seddon is making me some 160Hz horns with 1.5" throat for a different application. Don't intend to use them with the S2 but would be an interesting experiment to see if the above behaviour is reduced.

Chris,

The removing of the bug screens very very seldom causes a positive effect in compression derivers. (My view about it are below).In fact among all drivers that I know there is the only one deriver (T350) where the removing of the bug screens works beneficially. Still it works  fine in the T350 just juts because the bug screens in there sited right next to the diaphragm (a few mm) and do not “damp” it with the air between the diaphragm and the “bug screen’s impedance”…. the as they do practically in any other compression driver.

The negative effect that you observe, I think, has nothing to do with the S2’s internal flare. It looks like the S2’s internal flare is about the 180Hz or something like this. All of those compression drivers have very low internal flare. At that time when they were made the compressions drivers used in 2-3 ways installations and they foolishly tried to push out those drivers to the max LF. It started from WE, RCA and Klangfilm and then was embraced by Klipsh, Vitavox, Alteck, JBL and so on… They were not preoccupied at that time with quality of sound but rather about the getting the max pressure at given frequencies… Do not forget that all those vintage compression drivers that we use today never meant to be use in home installations and were targets for large sound reinforcement systems where the efficiency and the ability to cover large spaces was prominent (movie theaters, large public events and so on…)

Anyhow, regarding the bug screens. I had a post before:

http://www.goodsoundclub.com/TreeItem.aspx?PageIndex=3&PostID=974#974

that might bring my view about the bug screens. I would defiantly keep then in there.

Rgs,
Romy the Cat