Morel drivers are reasonably priced. They are generally copies of Dynaudio drivers, sometimes with a few twists(like double magnets). The fact that the Morel name doesn't carry the Dynaudio cache, means you get to pay less. Sometimes MUCH less. The information you were given about Vifa is quite correct. Actually Vifa and ScanSpeak are the same company. If you do not want to spring for the Morel MDT33, then go with the Vifa D27TG line. The exact model depends on what resonance frequency you need, presence of rear chamber and/or shielding or not, etc. These silk dome tweeters range from $18 - $25 over the net. I will not tell you they are better than Dynaudio, the Morel MDT33, or ScanSpeak, but they are much closer than anyone would expect. Very easy to listen to, yet extended and wonderfully detailed. Will easily handle all of your requirements. I am of the opinion that what is behind a driver is more important than the driver itself. The right crossover design/parts/construction will make that $20 tweeter sound better than a lot of people using the $120 tweeter. Please check out the Reliable(Rel)/MIT caps(same company now, I believe). Use the best capacitor that corresponds with the value you need. Teflon or polystyrene w/aluminum, tin, or copper foil if possible. Also use good wire inside the speaker. Teflon insulated high purity copper or silver is cheaper than you think(less than $15 to do both speakers with silver). |
We have two areas of disagreement, Carl. First, the easy one. The Morel 6" midrange used by Eggleston is polypropylene, not paper. No room for argument on that one. The second point is more a matter of opinion. In my experience, a $25 tweeter(such as the aforementioned Vifa) can easily sound better than the $100+ models by using exotic quality parts behind it, coupled with good crossover design. Those parts would include film(polystyrene or teflon) and foil(aluminum, tin, copper, or silver) capacitors(haven't tried oil filled), silicone wire wound resistors, and reference quality wire. How many loudspeakers use these capacitors or resistors? I guarantee you it is an incredibly short list. And usually they will only use those caps to bypass a cheaper(but still good) one. That being said, the more expensive tweeter with those same exotic parts will be superior to the cheaper tweeter. No disagreement there. |
I should clarify one of the arguments I have been making. You CANNOT use any $25 tweeter to get the kind of results I was speaking of. In fact, of all of the drivers I have come across, only a scant few are capable of excellent performance. Most sound like $25 tweeters. I do not like metal dome tweeters in most instances(and they usually dominate this price point). To my ears, they are much too prone to harshness, distortion, and ringing than a soft dome. Most of these drivers have to be compensated for at some stage of the game(in the crossover, electronics, or interconnect/speaker cable), and that to me is just not right. I find the silk dome Vifa D27TG to be an aberration. 95% of the performance of the expensive tweeters we have been discussing, for 20%(or less) of the price. I used to dabble in some Vifa(among others) tweeters, and thought they were competant, but not outstanding. Just very commendable performance, especially for the price. But the D27TG line redefines what one can expect and hear. I do agree with Carl(as we have both stated here many times) that the Focal tweeters are horrendous. Whether they be Ti, TiO2, or Kevlar, they always send me running as fast as I can away from them. I have not heard the expensive JMLabs line, but I have heard some mighty expensive products that use these tweeters and wondered how anyone could ever buy them. |
Carl, the October 1997 Stereophile does say that the driver used in the Eggleston is polypropylene. In several places, actually. And in the first paragraph of page 193 Bill Eggleston is quoted directly, "It's a custom version of a 6" polypropylene midbass driver from Morel that incorporates a 3" voice-coil and a double-center magnet". I also had several conversations about speaker design with one of the workers over the phone when the review came out(which included this Morel driver - which I had previously used). I find it refreshing for a company to be so open as to what their speakers incorporate. Perhaps, that is why their speakers are so good. They keep an open mind. I agree with your opinions regarding the Morel and Dynaudio drivers you mention. I do state my opinions are just that; please see my first post in this thread. Never do I claim I have all the answers, or am smarter than anyone else. |
Thank you for chiming in Chipster. And you are correct. The vast majority of Morels you see of this model are paper. Perhaps that is why Carl takes this position. But, different designers have different preferences and reasons for doing what they do. Eggleston felt polypropylene superior. Reason given to me was that their test for a midrange driver was to play piano, very difficult to get right(try it sometime - and give it a REAL workout). The polypropylene was superior, due to the structural integrity of the material compared to paper. Less breakup. But a test using only one criteria cannot not tell everything. I have heard some speakers over the past two years that have featured paper cones because the designers found them to be more musical. Triangle would be the most recognizable. It could be that one who built an expensive speaker such as this feels that polypropylene was de riguer. May be even expected to use polymer cones to be taken seriously. I know I got into that mindset. That is dangerous, as to fall into the trap of dogma is limiting. I have built a bunch of speakers, and found polymer cones to be superior. But, in retrospect I have to rethink my position. It is sometimes rare to be able to be able to compare apples to apples. Historically, the driver manufacturers have had other advantages built into the polymer coned drivers, as they are usually part of a superior line. But, if all things were equal... I adamantly feel that speaker design(and every part of it) is by far the most fraught with disagreement. What is false today may become the truth of tomorrow. The one constant of the speaker hobby is change. |
By the way Carl, if you need that article I could fax it to you. I have it right in front of me. Despite our disagreement, the content of the article is quite educational. A lot of insight into their philosophy(but a bit overboard on the praise). More so than any other Stereophile review I have read. And if you have further questions, the people at Eggleston(I presume their restarting the company has lasted) are fantastic. They will answer any, and I mean ANY question you have. And will even ask you for advice, preferences, and experience. They hooked me up with Swedac(dampens panel resonances). Wow, someone who actually will admit that they don't have all the answers and are learning every day(just like all of us). |
Ehider, I hope you proceed with your project; using one of the tweeters from the Vifa D27TG line. I have personally found that they mesh extremely well with Seas midbass drivers. You could choose from either the P17(6.5") or P21(8") line(polypropylene with or without phase plug). The magnesium versions of these drivers w/copper phase plugs are used on some of THE finest speakers around(Hales, Coincident, etc.). The smaller one may be preferable if you're building a 3 way design, or will be using a strong subwoofer. You could also use a Morel driver. Morel 6" would be MW162, MW164, or MW166, 8" would be MW265 or MW266. Both companies may now have different versions(and part numbers) of these drivers. Pardon me as I am using 5 year old literature(last time I built anything with these parts - sorry). A simple first order crossover will sound very nice with this combination. Use a polypropylene and tin foil Rel or MIT cap on the tweeter leg. You may also want to bypass this with a polystyrene or teflon and copper foil cap(yields an excellent improvement for the money). For the woofer, I recommend a 12 gauge coil from North Creek or Alpha Core Goertz. The North Creek offers a more relaxed, liquid tone, Goertz is a bit more analytical sounding to me. Try this combination out. If the tweeter needs attenuation(depends on the midbass driver you mate with it), use a 1 - 3 ohm, 10 watt silicone coated wire wound resistor from Ohmite(or equivalent). Please do not use any other type of resistor, as these are the only ones I have come across that will not add the harshness, grunge, and distortion most people will expect from this tweeter. Buy the resistors from Mouser Electronics, as their prices are roughly a third($1.75 - $3) of the what the speaker suppliers will charge you. I presume you are going to be using solid state electronics. If that is the case, go with copper wire internally. If you know you will be using tubes, you may want to consider silver. Both Orca Design(20 ga.) and Home Grown Audio(22 ga.) sell excellent copper wire, the HomeGrown having teflon insulation(better). I recommend braiding enough wire to achieve 17 gauge to the tweeter, and 12 gauge to the woofer. Using the aforementioned parts, you will be able to build speakers for $125 - $200 that a manufacturer would sell for more money than you would care to believe. And you will not have to worry about power handling. Good Luck with your project! |
