Crossover questions

Well, good luck in your project. I'll check out that iprimus site.

I never said Accuton was new; I said the Diamond dome was new. It will be interesting to see which manufacturer uses it first.

The sensitivity for the Emit-B seems higher than 90dB to me. The sound is fantastic imo; far more detailed and dynamic than I was expecting. It's a modern unit, with Neodymium magnets, so it's bound to ouperform those Infinity units you heard in the 80's.

Also, the published sensitvity for the new Raven R-1 is only 95 dB, the higher sensitivity is for the previous models (now discontinued). I think a pair of the Emit-B's in parallel would equal or exceed that sensitivity. Keep in mind that neither of these small tweeters will work below 3kHz.

As I've said before, if you absolutely want to run a midrange driver "flat out" you should consider a fullrange speaker like a Lowther or a Fostex. I've not heard the Fostex drivers, but their specs look more than adequate for their price, even a match for the Lowthers. The 8 inch model has nearly 100 dB sensitivity!! A series crossover isn't quite the same thing as running a fullrange driver with no crossover at all, imo.

Have you looked at Madisound's site, under Fostex drivers? Also, their ribbon tweeter looks about as good as the Raven R-1, and the Fostex one is only around $100...half the price.

I had thought that your goal was to throw something together for your secondary system, and to experiment; I didn't realize you wanted it to be a "statement" project. Those can be difficult and time-consuming...and let's face it, neither of us is a world class designer.

I, too, am no fan of Focal tweeters. Problem is, if you want to use only one tweeter, and decide you'd rather have a dome than a ribbon, the Focals are the only ones with high sensitivity, without horn loading.

The problem with using compression drivers and horns, is that you wind up padding them way down to match the lesser sensitivity of the midwoofers, so a lot of power gets wasted in the crossover, and I'm not sure it's even possible/ideal to use series crossovers in such an application.

I think you'll find, that unless your living room exceeds perhaps 7000 cubic feet, you won't need a speaker higher than 100 dB sensitivity (even with only a 3 watt amp)...and in any case, without the proper room treatment and placement, you'll hear more of the room's echo than you realize, imo.

Thank you Noquarter. You have graciously provided more information than I could ever expected. I am endebted to you. If you don't mind, I will get into contact with you at some point outside of this thread to further discuss some things.

You are absolutely correct in raising the issue of this being a secondary speaker project or a "statement". To be honest, I easily fall into this trap. I go way overboard. A very negative byproduct of my love of the speakerbuilding hobby. It is by far my favorite facet of audio. In fact, spurred on by my thinking of the past few days and your assertion, I discussed this with my girlfriend last night. This was supposed to be a secondary speaker. I really should just buy something along the lines of 4 Vifa 6.5" midranges and 2 Vifa D26 tweeters. Run the mids with nothing in the circuit, and connect a not overly extravagant film and foil cap on the tweeter leg. Throw them in a reasonably well constructed box, wire them up and call it a day. Perhaps, I should revisit that for this project.

But, I have still haven't ruled out doing something where I can build my speakerbuilding skills/experience further...

One of the higher sensitivity Ravens I was referring to was the Raven R-2(there is another). If I do decide to use one, hopefully they have not been discontinued. I did hear the Raven tweeter in a few newer designs from Acarian systems, and my initial impressions are quite favorable. If this tweeter really can offer me this detailed, yet smooth sound, coupled with this level of output, it is definitely something that would be on my short list.

Good points on the horns. That is actually what I originally envisioned. Aim for a sensitivity from 92 to 95 dB/2.83V.

As far as the Fostex drivers are concerned, I did visit the Madisound site. While they look good on paper, as I previously stated, my real world experience with them was in no way favorable. Yes, their sensitivity is high, and their operating range more than extremely broad. Just that if I am going to build or buy a loudspeaker, it better not sound like that. Able to play lively and loud, yes. But to my ears, along the lines of the way a clock or table radio sounds. No sock or punch. AT ALL. My hope was that you would have also had heard Fostex. To tell me whether what I heard was just a poor execution of the driver, or an affirmation of this being what it sounds like.

The fact that we view Focal tweeters in the same light shows me that we do think in parallel ways, at least in this area. And, also in our belief that a driver with no crossover should be better than one in a series network.

So far, the only speakers I have heard with the series crossover fresh in my memory is Roman Audio. Very, very impressive. Yes, this hyped up, patented DiAural crossover is actually just a series network! Just that it contains no capacitors. SonusFaber has supposedly used in the past with a tweeter, so how enforceable is the patent?

I also heard Fried a lot in the past, but would need to hear them with my current ears/mind, and with the type of gear I use.

Again, thank you.

You are quite welcome. I've always felt that the problem with "highend audio", is that there aren't more folks like us. I have to laugh, when I think of all those consumers that take loudspeakers and room acoustics for granted, and instead pay more attention to "tweaks", like gold-plated titanium rollerballs, etc.

I look forward to hearing from you in the future.

Did you happen to hear that Alon Statement speaker? it's the only one I'm aware of that uses the Ravens, they're the smaller R-1, and it uses 6 per channel I believe.

The speaker I'd like to hear, is that Impact "Airfoil" bending wave model...supposed to be a new take on bending wave drivers, uses them in a line array, fullrange down to about 100 Hz.

Does the Coincident speaker model you have not use the Seas Excel magnesium coned midwofers? I thought they all used those magnesium cones...the thing with them, is that you can never get rid of that ringing, even with an infinite slope crossover. It's just that it's essentially inconsequencial in the final speaker, since the ringing still is mostly focused on-axis.

Metal cones do have an efforteless controlled snap to the sound, I have to admit. I own an aluminum-coned Seas, for yet another project. The corresponding magnesium model rings somehwat louder than the aluminum, though...but that solid copper phase plug in the Excel versions sure looks awesome.

In my opinion, the 8 AWG North Creek coils get very close to the performance of not having a coil at all. However, they aren't exactly the same, obviously.

No, I've not heard any of the Fostex line. I'm curious if the driver you heard was mounted on a baffle in a finished design, and if so, which model was it? Was it any of the current ones in production, as listed on the Madisound website? Did it use a rear-loaded horn, a front-loaded horn, or both?

I'm trying to decide which 4 inch midwoofers to get, for the tiny "monitor" project with the Emit tweeters I bought. There is an older Vifa 4 inch polypropylene cone that has an EXTREMELY smooth rolloff, and might work with no crossover: the P11WG-00-08.

I may try using this one myself, but according to the Solen catalog, it will only yield an F3 of 60Hz, and I was hoping for a tad lower.

If I can't find a treated paper 4 inch cone with a low enough Fs, I may try and use that poly-coned model I mention above. It's just that I'm getting tired of the sound of poly cones. They have the advantage one you go bigger than 6 inches diameter, but not for 4 inches diameter, imo.

All would be fine, if Audax's new "polymer chassis" line, didn't feature back plates WITHOUT vent holes for the pole piece. Why anyone would ever buy midwoofers without vented pole pieces is beyond me. And they even charge as much for this new polymer line, as they did for the premium zinc-chassied line. That just seems outrageous to me.

I own 6 of those too (they're spectacular imo), it's the treated paper version of those found in the Pipedreams. They're discontinued now, so they only sell the carbon fiber model, again as found in the Pipedreams.

Hey Trelja, i know a guy with four mid woofers from a set of Coincident Eclipse's. I think that they are relatively efficient according to Coincident's ratings ( appr. 92 or so...), easy to drive, no fancy crossovers or notch filters required, etc... They might work great for your project. I bet that he'd get rid of them pretty cheaply compared to what they cost brand new. If you think that they might work for you, drop that guy an email... : ) Sean
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Hey guys, maybe we should start a club? Yes, loudspeakers and room acoustics are the first thing to take care of. I love "audio salons" who offer to come over and "evaluate" your room(because I couldn't possibly know how to set up an audio system), when they should have someone come in to evaluate theirs first. But, how about those rollerballs? Do the gold plated ones really sound better than the nickel? Kidding of course.

Sean, I remember us discussing Coincident drivers in the past. Are these the same drivers as those? From what I remember they were a Seas cone, perhaps in the P17 series. There is a chance I would be interested in them, but one of the goals of this project would be to build a loudspeaker that sounds(and is) different than my Coincident.

I am sorry that Israel didn't get back to you in regards to crossover design. From what you indicated, you felt that Coincident might be running those drivers flat out in the Super Eclipse. Any further thoughts on that?

Noquarter, my Coincident speakers are the Digital Master w/Troubass subwoofers. If you go to Coincident's website(www.coincidentspeaker.com), you can find the Digital Master in the "reviews" heading(Audio magazine, Feb 97). They are truncated pyramid(where the time alignment comes in) satellites that use the Troubass subwoofers as stands, ala Wilson WATT/Puppies, Verity designs, etc. Only they were aimed at the tube/SET crowd.

The midrange drivers are from the Seas Excel line, the P21 series(I now forget exactly which model, my apologies). A polypropylene 8" driver, with inverted butyl surround, phase plug, and according to Coincident a 5 1/2 pound magnet. Exactly mirroring your statements, the magnesium cone drivers were not appropriate in this speaker because of the ringing. Magnified in the 8" version, and even more so at this relatively high crossover point(for this size driver) @ 2 KHz. The tweeter is a silk dome. Crossover is a statement in simplicity; first order, a capacitor in series with the tweeter, and a coil in series with the midwoofer. The review's only criticism is the lack of deep bass, which is obviously not a problem in my setup as I use the(perfectly matched to the Digital Master and Troubador) Troubass subwoofers. 10" drivers in large, sturdy rectangular cabinets. The literature states that they produce 22 Hz @ 105 dB, with less than 1% distortion.

The sound is very impressive. Dark, pitch black background. Fast, very alive, yet powerful sound. More authoritative(to me) than more recent Coincident speakers. Not as SET friendly as the newer designs, however. Detail is excellent. Soundstaging is as good as I have ever come across. I have been around a lot of speakers, but these were the only ones I have ever come across that I immediately fell in love with and KNEW I needed to own. I have never again come across that feeling again, and am still completely crazy about them.

There is just something inherently "right" about the sound. Whether it is a result of the time alignment, well constructed dead cabinet, simple first order crossover, etc., or the sum of it all, it is an example to everyone in audio who thinks that the sound of the designer(via complicated designs and even more complex crossovers) can ever be better than the sound of the materials themselves. And while I may have thought I knew something about speakers, I really didn't know anything. Just go with whatever the parts offer you, stay the hell out of their way, and let them speak for themselves. That is as good as they will ever get. Another confirmation to me(it took me long enough) in seeing that simpler is better.

Your statements about the metal cones were all pointed out to me in conversations with Israel. I pick his brain as to anything he would change with the speaker. I wanted to take them as high as they would go. His belief is that the only change that can be made to improve the speaker is upgrading to the ScanSpeak Revelator tweeter("You'll think you bought a new pair of speakers"). My suggestions were the magnesium coned mid/woofer, upgraded coil, cap, and wiring(silver). He has never been enthused about any of these. I still maintain that a better coil(such as an 8 gauge from North Creek), film and foil cap, and better wiring would HAVE to make things better.

I also once asked what his opinions were about this speaker's use of an 8" midrange as being a detriment. To which he strongly disagreed, saying that the performance and speed of this driver are wonderful. That this is a favorite speaker of his, and that he would put it up against anything produced by anyone. I guess it is a bittersweet thing that his previous(very interesting) designs(cabinets and coincident drivers - where the company's name derived) are no longer produced because of the success of Coincident. Those cabinets just require too much work.

The Acarian speakers I heard the Raven tweeter was the Statement. But, also in a new smaller line(Exotica), which also feature Seas magnesium coned drivers w/copper phase plug. The Exotica was showed to me by Marilyn in a separate room(that wasn't being used) at the NY HiFi Show. I told Carl I liked the sound of the Raven in the Statement, but that $120K(?) was WAAYY over my head. Carl took Marilyn aside and spoke to her, then she told me to follow her. We talked for a while about the Raven and alnico magnets, and she made me promise to give the Exotica a thorough audition at a local dealer(in Philadelphia). At the audition I saw that the Raven held amazing potential. Well, in Carl's hands at least.

Elliot Zalayet carries so many products like this in his Long Island showroom. I used to see them when I went up there. Raven, Cabasse, Accuton, Focal, and Vieta drivers. He is a little offputting for some people, but he is really a super person to have in this hobby, very helpful and knowledgeable. 7 or 8 years ago, I asked him why these drivers weren't being used in high end speakers. His sanitized comments were 1) the companies were not as creative, and that audiophiles are not as knowledgeable(so they don't demand the drivers) as they both tell us and 2) these drivers are more expensive. Since then, basically the only drivers of these "unknown" companies that have surfaced in high end in any great measure were the Focals.

The Fostex drivers I heard were the 8" drivers, complete with "whizzer" cone. In a medium sized, vented cabinet, with no other drivers. Not a dead cabinet, and meant to be that way. A homage to the designs of the past, as these designs basically are. Pre HiFi. I kind of think these drivers may be perfect in that element. But, it isn't my taste. After hearing it, my impressions were that was what these designs basically were. A page from the 40's and 50's, when 35 wpc was astronomical. Loudspeakers needed to be efficient, and not demanding in terms of current. Bass was not in the equation(was there no power for it in those days?). The speakers played loud enough, and were not slow in the least. But, like I said, it had the sound of a table radio to me. Pretty much what people's systems of those days sounded like(such as my grandparent's stuff). Richness, if ever there seemed cloying, and not of the dynamics and punch we have come to expect from the past few decades. So, I wonder if this guy(a friend of my father) who built these speakers for his system did a poor job, or is it the Fostex? My father, who is a TOTAL bass freak(and solid state type), thinks they are the worst speakers he has seen someone put together in a long time("He should have just used 6 X 9 Jensens...").

I can certainly empathize with your search for drivers. I wish you luck in this project with the EMIT tweeters. I am also thinking I should take a flyer on them, great price. Maybe I could put together a monitor like you are also doing, and give them to my brother-in-law who NEEDS speakers in the worst way, but is unlucky in that he is married to my sister(who won't allow him to buy anything). A fun project to get the blood flowing again, nothing as serious as what you are building.

Is it me only, or do you also face these issues often? If only I could get this magnet with that cone, or that cone with that surround, that surround with this basket, or that impedence, the list goes on and on... Jokingly I say that it's just like car companies. When they come out with a new model I have been waiting for, I have to wait another 3 or 4 years before the stuff I want is available in it. Either that, or they redesign the car all over again before they get to what I want, or my tastes have moved on altogether.