Pendragon Slayer in Bipole
If I take the same 10.5 in wide x 22.5 in deep x 54.5 in tall cabinet but mount the drivers front and back at 18.5 in from the top in a bipole push-push configuration with a big floor-firing vent (5 in x 8 in x 3.5 in long) with a 4 in gap between the speaker and the floor, here is what I get for the frequency response. The bass at 20 Hz is now in the low-mid 80 dB range. There is a dip at about 130 Hz though and bump at 600 Hz. I will try to optimize this some more, but this is interesting.
If I take the same 10.5 in wide x 22.5 in deep x 54.5 in tall cabinet but mount the drivers front and back at 18.5 in from the top in a bipole push-push configuration with a big floor-firing vent (5 in x 8 in x 3.5 in long) with a 4 in gap between the speaker and the floor, here is what I get for the frequency response. The bass at 20 Hz is now in the low-mid 80 dB range. There is a dip at about 130 Hz though and bump at 600 Hz. I will try to optimize this some more, but this is interesting.
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When I look at that Pendragon I see similarities to a Dunlavy design. Your dragon slayer seems to abandon that design completely. I really think the Pendragon has more to offer than what you came up with so far. Using the Pendragon layout with a TPL150 substituting the 3 tweeters might work really well though. But I don't think slaying the dragon is as simple as you make it out to be...
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One of the things the reviewer noted was how vertically big the soundstage was with the Pendragon. That probably has a lot to do with the separation between the two drivers. The three tweeters will probably cause a less vertically tall soundstage due to line array focusing. This may be something important but I can look at vertical polar directivity plots to see if it matters.
I think it's worth investigating 🙂. What I remember reading about the Dunlavy speakers is that you have to be a bit further away from them to get the real bass output.
These dragons seem to work in a similar fashion. Both of the 10" woofers will sum best at some distance. Dunlavy used sealed enclosures though.
I like the concept of the dragon. They might even have roll off on both outer tweeters making the wave front behave more like a point source?
These dragons seem to work in a similar fashion. Both of the 10" woofers will sum best at some distance. Dunlavy used sealed enclosures though.
I like the concept of the dragon. They might even have roll off on both outer tweeters making the wave front behave more like a point source?
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I just looked at the Dunlavy photos and it looks like they are taking it to the extreme ends of the cabinets to place the drivers. Interesting and this reminds me of some of the very tall double mouth BLH speakers that are reported to give a very big soundstage. This may take the Slayer on a very different architecture - but this is good, it makes us think and break out of the box speaker mold. I am thinking of internal folds to the TL to relocate drivers and have larger separation between drivers yet maintain phase between drivers. Hmmmm....
I hope this thread leads to a solid design. If I could build the Pendragons for $500 I would. Closest thing I have now is an old pair of 2-way Toby speakers with full range 6x9 and a small crossed tweeter. Excellent imaging and excellent bass. But I always want more...
I read in one of the reviews that the drivers are customised for Tektron by Eminence. What exactly and to what degree is not mentioned...
Tekton M-lore Speaker Review
Tekton M-lore Speaker Review
I am not putting much cred into reviewers comments about custom drivers anymore given that Jay1111 pointed out that the supposedly proprietary dimpled tweeters were custom for Tekton made by Scanspeak when they look like off the shelf units from SB Acoustics. See post #2. If Tekton is a 1 man show with delivery of a handful of speakers a year, it is highly unlikely that there are custom drivers involved.
I do not want to sound rude, but that is hog wash. None of the drivers used in the Tekton range are custom made, its all just sales hype to try and protect their business.
The BP102 is also the standard 4ohms version used so that they can get an 8ohm speaker.
I have a price point that is aiming for <$500 too. If you wanted to duplicate the Pendragon as-built, the drivers alone are ~$700 (4x$80 + 6x$60). Crossover, cabinet, biding posts are extra. So let's see if we can get this down to fewer tweeters. I think just swapping out the $60 SB Acoustic tweeters for a $15 Vifa x 6 and using Beta 10CX's can keep driver cost at $370.
Did you see the Seas version with 3x the Vifa XT25 SC90?
An externally hosted image should be here but it was not working when we last tested it.
Well I gotta say I am pretty psyched about the possibility of building something similar to the Pendragon with a pair of Beta 10CX's per cabinet. Luckily for me, I have so many other projects going on that I can't help but be a little patient while the details get kicked around for a while...
Not rude at all. I should have been more clear and put a question mark on my comment.
Its quite a claim by designer or reviewer to highlight custom drivers when they are not.. Still you never know, they might have custom stickers on the back... Very nice 😉
Dean
Its actually a cheaper version. Most people that have heard both versions prefer the larger BP102 version to the smaller 8" Seas version. The SB tweeters are superior to the cheaper Scan. I have a crossover for three of the SB's as used in the Pen worked out already. I will try to post a copy in a couple of days and yes it works real good, I think we are well on the way to putting that Dragon in the cooking pot😀
I suppose so: tekton-designcontent2011
I really like that XT tweeter (use it in my car) but it is not particularly well known for its low frequency use. Just noticed the above post 🙂. There are better (low frequency) performing XT's as well but they all have bigger faceplates...
I really like that XT tweeter (use it in my car) but it is not particularly well known for its low frequency use. Just noticed the above post 🙂. There are better (low frequency) performing XT's as well but they all have bigger faceplates...
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Room modelling results can be informative and interesting with impacts as large as 15 to 25db minimising room speaker interaction is almost always worthwhile and sometimes it becomes the most significant consideration!
I wonder if you agree that any stereo speaker that relies on such resonant phenomena with their wildly variable modalities and time domain disturbances is unlikely to have obtained the reputation that this one seems to have?
Room interactions are important which is why my sims include the reflections from the floor and back wall and I place the speaker at the location recommend by the reviewer or manufacturer. Speakers meant to be placed next to a wall often work poorly away from a wall and vice versa. From my simulations, the speakers with the best performance away from a wall are the bipole and the Karlson K15. The K15 has the ability to efficiently throw a flat bass shelf from 50 Hz to 150 the farthest with highest SPL compared to any other design. I can use a 95 dB 8 in driver and it will have a flat 50 to 150 Hz bass shelf 5 meters away for 1 watt input even when placed 5 ft from back wall. It doesn't have deep bass but much of MUSIC can be enjoyed without HT style bass rumble in the 20 to 30 Hz range. See the Speaker that Kicks Butt in Large Spaces thread if you are interested in this.
http://www.diyaudio.com/forums/full-range/237948-speaker-kicks-butt-large-spaces.html
http://www.diyaudio.com/forums/full-range/237948-speaker-kicks-butt-large-spaces.html
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