User211,
Read some of your earlier posts on actual Apogee speakers and looks like that we're in full agreement about the originals, including the Grands. Now discussing or arguing about a ribbon speaker project that as far as we know hasn't been produced and only exists as a diy prototype, never been measured, never reviewed, unknown specs, unknown build and one that neither of us ever heard. You as a believer & I the skeptic; this should be entertaining
!
1) Theoretically maybe but meaningless without knowing basic parameters and target SPL; efficiency is relative to energy requirements and SPL.
2)+3) These are his words from your link,
"Now those who know me know I don't actually have a full main system very often, as I simply cannot afford the amplifiers they require" Ok, so what is the real requirement
?
"17w amps went a long way, they give a pleasing sound imho", is this supposed to be proof of something? "Went a long way" to me means they didn't get there even in a small room and what is pleasing sound and at what SPL on what type of music? I can't tell you why he had people over and the single image posted doesn't inspire confidence in his setup with all those windows around. Whatever claims made are only his
own site and unverified by others.
Not familiar with your Graaf amps or their capabilities but not surprised with your results either, maybe for a better comparison you should also try tri-amping (which you can't with stock crossover) or at least bi-amping your Duetta and see what happens.
4) Price comparisons are meaningless and irrelevant to anything discussed but for the sake of argument;
There's no pricing for the Graz besides a starting price of $105k in 2009, so cost and value unknown. Taking your hypothetical $100k and aside from the fact that the Neoliths are a real world speaker from a well established company and the Definiteve's are neither, ML's ex-factory price is significantly less than the $100k. If the Graz went through the same sales channels its msrp would be north of $300k.
5) There's no product and no price, what am I supposed to make? Given your lack of expertise how can you judge someone else's competence? A good technician repairing electronics isn't the same as a design engineer. Technical ability doesn't automatically imply creative ability. I know this from years of manufacturing, IME creativity and design are far beyond even the best technicians I've come across. Hypothetically speaking, if I was going to make such a speaker I'd research a competent facility that can design and manufacture the product without wasting time & money dicking around, nor would I spend 3+ years restoring a single pair of Apogees!
6) Focus sums it for me, fine if doesn't for you but don't forget the context regarding sensitivity!
7) I misread something, so what? It doesn't change anything in my overall argument!
David,
1) Pure physics means a more powerful magnet field means less amp power is required. This is an undeniable fact. Neodymium magnets are a lot more powerful that the quite weak ferrites used in standard Apogees. I believe the ones used by Apogee are slightly below C9 strength. Neodymium's have 3 or more times the field strength.
2) Follow this link.
Definitive and 17 Watts. That's six channels of 17 Watt amps driving the Definitive. I tried a 50 Watt Graaf 50/50 on my Duettas and all you could get, at anything approaching a normal listening level, were farting noises of an amp driven into clipping.
3) If they wouldn't drive the Definitives to a reasonable level, why would he be inviting people around? He isn't saying they were killer, just that they would make some pretty good noises.
4) Is 100K dollars expensive? That's about £60K here - the same as an ML Neolith. Imagine the neo magnet arrays in there. I'd estimate about £10K's worth TBH. Plus the price of the Corian, the machining of said material, the expertise, the one off price of machining the metal holding the bass driver array (massive quite thick perforated metal sheet) and a lot more besides e.g. one off ribbons.
5) Make a pair for less, David. You wouldn't be capable of it. You almost certainly couldn't do it. You don't have the required knowledge or experience. Nor do I. The point is the price of expertise and the long hours put into these must have been seriously formidable. Free to Graz of course.
6) Improves focus like you said? No - it does a lot more as I said. Focus is not a generic enough term to cover the list of subjective improvements proper bracing provides.
7) Well done for fessing up you were wrong about Definitive being described as a non-dipole.
Graz is just a small scale one man band in Australia. The hi-fi press won't go near him for that reason. They want advertising deals in exchange for reviews in a lot of cases. There will probably never be the level of technical testing you seek published in a hi-fi mag unless he gets very lucky.But, at the end of the day, it isn't rocket science. I don't need proof neodymium magnets will improve efficiency substantially. I know it will.
Generally, neodymium implementations are not available in the new speakers, I believe. C9's will be in Advance 7. Synergy is no more. However, a phone call will probably get anyone what they would like if they are serious enough to take the risk and provide a deposit, I suspect.
I have to admit that I'm bewildered at the amount of blind support & faith a grown seemingly intelligent man is putting behind an totally unknown project by a man who wasn't good enough or worth the cost of repairing his own speakers. Is there a real world argument here that I'm missing? I'm not asking for anything in depth, sensitivity and load measurements are basic and available from any manufacturer worth the title. Plenty of competent 3rd party labs who could do it, including a reviewer with basic testing equipment at home. Does Graz supply any measurements for his replacement kits or is that all hearsay too? Keep in mind that I'm not questioning anyone's subjective impressions like what Ked has provided only a copy of the measurements that should have been done when quoting specs. Don't know about anyone else but I would to see more than
"Difficult to nail a dipole accurately in a room that is too small! Around 98-100dB/w guestimate" using a temporary set up when quoting specs!
My industry experience is different, advertising was never a prerequisite to a review by the known rags, favorable or otherwise! You're only assuming that the Definitives are ready for prime time and that the manufacturer is willing to give them up for a full review while ignoring that they're not a real world product but a partially finished diy project with an off the shelf digital crossover requiring 6 channels identical amplification. There's no media conspiracy here.
Relative field strength of differing magnet types.
The Apogee website is well out of date by Graz's own admission. Try this:
Apogee on Facebook.
BTW David neo magnets are a pain to work with. Accidents are possible. Stupid levels of force are required to correct errors. My restorer wouldn't touch them.
How long he's spent repairing a single pair of speakers
?
david
