Tube Nube Posted December 31, 2015 Share Posted December 31, 2015 I forgot to comment about the table saw -- Mine wasn't set up properly, initially. Or, if it was, it came loose. I found the set screw on the pulley attached to the blade was loose, and the pulley had migrated on the shaft, so the pulleys were out of alignment. I was lucky to find an on line manual to get it set up properly. Or at least better. It would have been nice to have extensions on all sides of the table saw so that these large slabs of wood didn't need to be held to be supported as they're fed to the blade. That made cutting the 5x5 foot sheets difficult to get right. At that point, I gave up on 45 degree cuts for bevel joining panels. I knew it would cause me to have an aneurism. Or at least many uncontrollable outbursts of profanity worthy of a Tourette's sufferer on amphetamines. Make sure your table saw is set up right, be sure to have a good sharp blade on there. That was another mistake in the early stages. And have a helping hand with you to assist cutting the bigger pieces, if that'd help. I realize I had help on my last speakers. Wish I'd waited for a hand on these ones. Still, I worked with these glitches ok. It didn't so much compromise the outcome as it did delay my progress. Just like a woman . . . a good table saw is hard to find, and hard to maintain in optimal working condition. 1 Link to comment Share on other sites More sharing options...
Benen Posted December 31, 2015 Share Posted December 31, 2015 Haha. Yeah fair enough. I'm not in a huge rush to order the parts so I will definitely wait until I know which ones to build. Yeah I've read that table saws are not the best for large rip cuts of sheet material because of the support issue. Maybe a track saw would be better suited? Harder to do repeat cuts when slicing everything up though... Link to comment Share on other sites More sharing options...
Benen Posted December 31, 2015 Share Posted December 31, 2015 Oh and happy new year! Link to comment Share on other sites More sharing options...
Tube Nube Posted December 31, 2015 Share Posted December 31, 2015 Many lumberyards will cut the wood for you. Might be worth having them cut the side panels at least. Link to comment Share on other sites More sharing options...
xam198 Posted January 2, 2016 Share Posted January 2, 2016 Hi everybody. I've been following this thread since several month, as i'm planning to make dtqwt. But like some others, i'm hesitating between dqtwt single 12' version and 212. It seems that the 212 is somewhat 10Hz lower, but at the price of the huge box. My room is 6x5x4m, i can't put the speaker more than 1 foot - 30 centimers - from the front wall, and i'm listening rock, pop, electro, symphonic original soundtrack. I've got a subwoofer (beyma 18lx60), but i'm using it only for home cinema and electro/techno music. Knowing that, would you have an advice on the choice ? I've made a model of a 212 with carboard box... it's huge ! So i think i will make it only if i'm sure it worth it, regarding to the single 12' version but how to know ?... Thanks for your help ! Link to comment Share on other sites More sharing options...
Tube Nube Posted January 2, 2016 Share Posted January 2, 2016 http://www.troelsgravesen.dk/DTQWT-212-Stu.htm Here is a link to the only builder on Troels' feedback page to report on the 212. It is unfortunate email addresses are not provided to allow us to invite Stu, this builder, to join us here and tell us about his project. Looks like he did an excellent job building it, and it would help us out to know how it sounds -- especially if he's ever heard another version of the DTQWT for comparison. Link to comment Share on other sites More sharing options...
Tube Nube Posted January 2, 2016 Share Posted January 2, 2016 This is interesting. In a discussion of DTQWT's on this build thread: http://www.audionervosa.com/index.php?topic=3070.210 A favorable comparison against the Verity Lohengrin II (costing $80k) speakers goes unchallenged! http://www.soundstage.com/revequip/verity_lohengrin_ii.htm. Link to comment Share on other sites More sharing options...
xam198 Posted January 3, 2016 Share Posted January 3, 2016 Yes i've read this topic on audio nervosa - in fact i think i've almost read everything in english on the web referring to dtqwt Unfortunately, the builder of the 212 is also curious of the comparison between different models of dtqwt... One thing is sure for me, is that if the theory is exact, 10Hz gain in low frequencies seems to me a huge improvment, but in my room and with the music i'm usually listening, will i hear it, i don't know. Link to comment Share on other sites More sharing options...
Green Wagon Posted January 3, 2016 Share Posted January 3, 2016 Just a heads up.... Jantzen have their stock take / end of financial year at, the end of the year. They have their Denmark and Poland offices/factories to go through. They don't actually resume until jan 6th. Their shut dates are on their front page. And then they will have a massive back log of emails and orders to process. I've had 'real time' email conversations with them when it's been 1 am over there. They work hard... bloody hard, and always manage to be polite. 1 Link to comment Share on other sites More sharing options...
Benen Posted January 5, 2016 Share Posted January 5, 2016 If I'm already looking at something as big as the 212's maybe I could look at the obl-15's. But Troels does says that they beat any other construction on his site, regardless of price and they look very easy to build. They are monstrously wide though! Went looking at table saws yesterday. Tossing up between a jet and a sawstop. Still have some time to decide what to build. I can't wait! Link to comment Share on other sites More sharing options...
xam198 Posted January 5, 2016 Share Posted January 5, 2016 Benen, we are following the same path, i also thought and read about OBL 15 yesterday. Another interesting thought about dtqwt -12 : http://www.audiocircle.com/index.php?topic=132147.0 Read the commentary of Richidoo. Link to comment Share on other sites More sharing options...
Benen Posted January 5, 2016 Share Posted January 5, 2016 Nice one. What's you're thinking? I may have to build a cardboard cut it to see what I'm dealing with as was suggested preciously. The room is large and has very little in it. Also tossing up between a table saw and a track saw which is equally difficult. Link to comment Share on other sites More sharing options...
Tube Nube Posted January 5, 2016 Share Posted January 5, 2016 Benen, we are following the same path, i also thought and read about OBL 15 yesterday. Another interesting thought about dtqwt -12 : http://www.audiocircle.com/index.php?topic=132147.0 Read the commentary of Richidoo. Richidoo makes some interesting comments, both positive and critical. I did begin to wonder if his powers of observation reflect astonishing discernment or, alternatively, confabulation. For me, his reported ability to hear the compromising impact of the binding posts settled the affair. Link to comment Share on other sites More sharing options...
xam198 Posted January 5, 2016 Share Posted January 5, 2016 I made the cardboard cuts : for me it's ok as soon as the speakers are against the wall BUT i know they can't be, and positioning them at 2 feet from the wall change a lot for me. Reading the last comments of Richidoo settled the affair for me too : i would have tolerate the big box if i would had no doubt about some very very high quality of the bass, that the reason for accepting such huge box, but here, i'm not sure anymore so i will go for dtqwt or OBL 15, and too bad for the deep low bass, i will make with the dry, clean and less deep bass Link to comment Share on other sites More sharing options...
Tube Nube Posted January 5, 2016 Share Posted January 5, 2016 (edited) Xam, Richidoo's criticism of the bass is the first negative I've heard about this. Usually people talk about the fast and punchy bass response as surprisingly good. To my ear, the sound of the bass from the DTQWT is better than that produced by my (Rythmik) subwoofers, FWIW. Keep in mind the 212 is sure to be a different animal than what he heard due to the bigger cabinet and having twice as many 12" bass drivers. It looks like many people are keeping their DT's about a foot out from the wall, rather than 2 feet. Mine are 2 feet. 1 foot will give you a deeper bass response. (Deeper than the 40 Hz I'm measuring with Room EQ Wizard at my listening post). I'd be very interested in following your project if you decide on the open baffle. I hope you'll do a parallel build thread so we can follow along, learn, and hear about your openly baffling exploits. ;-) If transmission lines aren't exotic enough for you, OB is really getting exotic. Edited January 5, 2016 by Tube Nube Link to comment Share on other sites More sharing options...
arpavieja78 Posted January 6, 2016 Share Posted January 6, 2016 For me, his reported ability to hear the compromising impact of the binding posts settled the affair. I think the same, that is not technically serious and binding post are provided by Jantzen, standard quality, but not the slightest influence on the final sound. That's voodoo audio, it shows ignorance of richidoo. 1 Link to comment Share on other sites More sharing options...
Tube Nube Posted January 6, 2016 Share Posted January 6, 2016 Yes, Rolando, it was a strange posting I have to say. If he went to all the trouble to build this speaker, why didn't he swap out the binding posts for some AudioPhool grade alternatives? Maybe because the weeping wail of "cone cry" made these speakers unsalvagably unlistenable. But why oh why is such an individual with such powers of discernment slumming it in the DIY world. It seems likely there is nothing DIY that will ever satisfy! I'm sure these are not faultless miracle speakers, but from all I've read, I think they are among the better ones available in the DIY world. I find it very hard to believe a company like SEAS would crank out a driver for Troels that suffers from bad habits to an excessive degree. While I'm on the topic of speaker limitations versus user limitations, how much toe-in are you guys using? I'm scared to mess with my positioning, but have them toed in to where if I taped strings to the inside side panels, and took them straight back, they'd converge just behind my head. Link to comment Share on other sites More sharing options...
xam198 Posted January 7, 2016 Share Posted January 7, 2016 Hmm, interesting. Interesting for serveral reaons, one because since i'm not totaly fluent english as you must have noticed (i'm french), i misunderstood the problem of "his reported ability to hear the compromising impact of the binding posts". Another point is the consideration of how loud can play dtqwt. I know that OB can play louder without risk for the JA8008. Troels talks about that, i found a testimony on that on the web. As i'm using my speakers for music but also for Home Theater, sometimes they play loud on film, but difficult to know if loud loud for me, is the same for for Troels and for others (my room is 6x5x4m). As Yoda said, "meditate on this i will". Link to comment Share on other sites More sharing options...
BioBrian Posted January 7, 2016 Share Posted January 7, 2016 (edited) Hi, @@xam198. You might get support from others in this opinion - I think the DTQWTs are more than capable of easily filling your room. I use mine (DTQWT-12, with twin 12" woofers) for both stereo and multi-channel. The volume setting for Blu-Ray 7.1 or 5.1 is usually the same as for stereo. When I have 8 speakers all correctly balanced, the volume has to stay that low, to protect my hearing. My room is only a little smaller than yours, at 6 x 4 x 3.6m. The big loudness difference in movies tends to be in the bass. Explosions and car crashes, etc, can be overwhelming. I agree, the OBL-15 could be played louder without speaker damage, due to the bank of (1st order) caps reducing the bass output of the JA8008s, although I'm confused at the graph Troels shows, with the roll-off of 6 dB between 100 and 200 Hz, then only about 3 dB below that, from 100 to 50 Hz. The 15" Ciare has an Sd of 830 square cm, by the way, which is less than 2 x 12", at 1040. I personally don't think the OBLs are that large - not as big as the photos suggest. Did you make cardboard models of them? And to other readers too - Troels mentioned Niels Henning Ørsted Pedersen's ' This Is All I Ask' album, track four, "Just In Time", so I decided to try it (you-tube) on my DTs - bass sounded pretty damn good! Very clear and just like a bass-player in the room. If the OB is better, it must be truly awesome. My recollection of the binder-post incident was that he stripped the thread on one while fitting the wire, and only found out some time later. He said it sounded right after he fixed it - unfortunate that his memory blamed the binder-post and Jantzen. That thread was not a happy read - I suspected poor quality plywood, and mistakes in the construction. The endless fiddling with the stuffing was pretty painful and must have been very frustrating. The dissatisfaction with the mid-range is strangely similar to mine though - he also mentioned flutes, but flutes (nearly all) sound horrible around 1700 Hz on all the gear I've listened to, so maybe he has the same recordings? I also suspect that the design mandate is quite pushing the boundaries though, regarding beaming in this region. But again in defence of the speaker - in my recent Blu-Ray discs of Lucerne Festival Orchestra, and Berlin Philharmonic, the flutes are completely undistorted, which is a huge relief. Brenton, I find the same toe-out works best for me too, and I'd be interested to hear from other 'users' about this. I do have a bit of trouble finding the best spot for my head sometimes, especially on 'fake stereo' TV programs - it's much better on good ones, like the incredible hi-def BBC stuff. Edited January 9, 2016 by BioBrian 1 Link to comment Share on other sites More sharing options...
Tube Nube Posted January 7, 2016 Share Posted January 7, 2016 Hi Brian, I wonder if you've tried listening to those flutes with a vinyl recording? ;-) I'm interested in what you say about a beef with the mid range. I'm not sure if mine are lacking something, or if the difference I think I hear is just because my last speakers were overly peaky in a certain range. What would be nice is a test recording where a range of different instruments covering the full spectrum play notes to a determined dB level, so the listener can hear, or use an spl meter to confirm a reasonably consistent out put level across the frequency spectrum at the listening position. Having said that, I realize I'm an idiot--I can do that test using room eq wizard. Indeed, double dummy am I, I've done it. I was focussing on the 20-100 Hz range, though, for Sub Woofing purposes. I don't remember what the upper 15, 900 Hz of the spectrum looks like. I have the vaguest recollection that it starts to fall off after 10,000 Hz. I can call up my saved results, and also re test, since moving my speakers around, but I suspect a listening test with real instruments would really be a nice way match up the techie approach with the sound of real instruments, if not real music. I admire these people who can use real musical selections to evaluate a system's performance, but that surely only comes with having heard the same tracks many times on many different systems. Link to comment Share on other sites More sharing options...
Tube Nube Posted January 7, 2016 Share Posted January 7, 2016 Xam, Sorry about that! I was trying to be "understated" and ended up not being immediately clear. Rich' quite boldly states that he can hear how the cheap binding posts compromise the sound, and that he can't understand why Troels doesn't hear it too. I think expectation effects are the basis of such perceived differences. I just do not believe that the binding post compromises the sound in any way that the human ear can possibly discern. But the old saying goes "seeing is believing", not "hearing is believing." Link to comment Share on other sites More sharing options...
xam198 Posted January 8, 2016 Share Posted January 8, 2016 (edited) Tube Nube, don' be sorry, that just because of my limits in English - i thought i was good enough but i see that sometimes i can miss essentials informations. You and the others are very kind to give me a lot of informations to make my choice. And so Brian, thanks for your post. To be honest, i don't like very much the esthetic design of OB15 and others OB, so if i can go the dtqwt , i will. And with the testimonies of everybody, i think i'm ok to come back to my initial choice - or more precisely my initial difficult choice dtqwt or big sister dtqwt 212 ... well until i change again my ming Edited January 8, 2016 by xam198 Link to comment Share on other sites More sharing options...
Benen Posted January 8, 2016 Share Posted January 8, 2016 So you're leaning towards the dtqwt at the moment? I'm leaning quite heavily towards the obl. Mainly for the ease of construction as I'm new to woodwork but also for the volume if I want it really loud! Link to comment Share on other sites More sharing options...
xam198 Posted January 8, 2016 Share Posted January 8, 2016 Actually i think i would slightly be frustrated about woodwork of the OB. It just will be my second diy speakers, but i loved the woodwork on my first. I made this model : http://www.htguide.com/forum/showthread.php?32615-Dayton-Classic-WMTMW&p=451181&viewfull=1#post451181 using this method : http://www.homecinema-fr.com/forum/diy-enceintes/2-5-voies-nomex-164-mix-sonus-faber-t30051919.html to have curved faces (i don't have photos of mine, they were on my broken smartphone). Complex but i liked to build them, dispite my non-professionial skills and tools in woodwork. I would like to make someting similar but using and discovering other method (bending mdf), so i couldn't do that with ob, but i think i could with dtqwt. So beetwen the woodwork, the quality i'm waiting of the speaker, and not to forget the budget, the choice is note simple, i have to decide of the compromises i'm ok to do. Link to comment Share on other sites More sharing options...
Cees01 Posted January 8, 2016 Share Posted January 8, 2016 Hmm, interesting. Interesting for serveral reaons, one because since i'm not totaly fluent english as you must have noticed (i'm french), i misunderstood the problem of "his reported ability to hear the compromising impact of the binding posts". Another point is the consideration of how loud can play dtqwt. I know that OB can play louder without risk for the JA8008. Troels talks about that, i found a testimony on that on the web. As i'm using my speakers for music but also for Home Theater, sometimes they play loud on film, but difficult to know if loud loud for me, is the same for for Troels and for others (my room is 6x5x4m). As Yoda said, "meditate on this i will". Hi, I am Cees from the Netherlands (sorry for the Google English) and I have built the DTQWT mkIII about 8 months ago. They sound fantastic after minimal 400 hours "warm up" and they can play realy loud. Sometimes 100dB and that is loud and not so good for your ears. Importent is the acoustics and the correct placement of the speakers and the listening place. Verzonden vanaf mijn iPad met Tapatalk Link to comment Share on other sites More sharing options...
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