DTQWT response
Copyright 2010-15 Troels Gravesen
DTQWT, built by Ralph/Belgium

I have built and cherish your DTQWT's about two years ago. I have always been a quad ESL63 listener and have never found a pair of speakers that satisfy me for any length of time other than your DTQWT's although very different speakers. I'm tired of placement and maintenance issues with the quads. Unfortunately I have recently moved to a small apartment in Brussels and the DTQWT's are now in storage. We are currently renovating a house in Italy which will be their new home... eventually? In the mean time I am sure your 3 way classic will do a good job for this current space. I was torn between your Quatro and the 3 way Classic. Just not sure about a 2 way? In case you are interested I ran the DTQWT's with aTubes4HighFi low gain modified Dynaco ST70 and a Transcendent pre amp. I have also built a dac using the teachings of Lukasz Fikus.. (very good dac). Many many thanks for your hard work and your kindness sharing it. You have provided me with a lot of pleasure. Warm regards, Ralph.


DTQWT built by Christer/Norway
Hello again.I have finished my dtqwt speakers,and absolutely love them.I think its one of the best speakers I have heard. It plays effortlossly and dynamic.But running the midwoofer fullrange I have experiensed overloading it acouple of times. (I know that is REALLY LOAD, but nevertheless...) I was wondering if you have any experience in any 3way design using the same tweet/midwoofer? If so do you think you could help me with possible suggested cab/network design? With best regards Christer.

Hi Christer, Thanks for sharing your experiences on the DTQWT. I sometimes use my Jungson amp for the DTQWT and yes, they can play very load, but it is possible at extreme levels to exceed the loading of the horns. Most likely you'll also exceed Xmax for the 8008 front driver too, being +/- 3 mm. I have to say that at these levels both our ears and the driver's voice coils may suffer overheating - and damage. If we want disco levels, we're into another ballgame and I have no immediate solution for this. Something like the 8008 based construction made by Lennart/Sweden, but I have no details on this speaker. http://www.troelsgravesen.dk/JA8008_response.htm. Best regards, Troels

Hi Troels! Thanks again for your quick reply!
I first want to say I think I`m falling in love with your dtqwt design. I ended up using the eminence kappalite 3012 ho drivers for the rear bass. I ordered them from BlueAran UK,with really good price and service. As for the sound,they never seem to stop amaze me. Super smooth and detailed midrange with perfect integration to the tweeter. The bass is very dry and fast but yet meatfull at same time (strange way of describing it but it is how I would describe it in a simple way).
The dynamic capabilties is what impress most for first time listeners, I would say its right up in the class with Klipsch and the like. The only downside for me,but not even close to a problem even waaay over normal listening levels, is overloading of the midwoofer at war volumes. With the house alone and the guys over for beer and Infected Mushroom and the like in the playlist I have experienced overloading of the midwoofer. But it is an almost impossible task to demand perfect reproduction of acoustical jazz and classic music AND be able to be driven fullrange and play techno/heavymetal at war volumes from one speaker, but I think this one comes really close. I also think I might have solution for the problem. I am saving up for the McIntosh Ma 7000 which have pre out/main in built in. I think I might run an active crossover between at maybe 50-60 hz and build a Bill Fitzmaurice Tuba HT subwoofer for the lowest octaves. How do think that sounds?
Oh yes,almost forgot: Pictures will come!! Best regards, Christer
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Hi Christer, As mentioned earlier, REALLY LOUD calls for special precautions and an electronic crossover providing a high-pass filter to the front driver may be worth a try, e.g. 1st order 80-100 Hz. If you use bi-amping, this may be accomplished by simply adding a series capacitor (a good one) in series with the input signal. Value depends on input impedance of actual amp. My experience with bi-amping has not been good unless the amps are exactly the same.  A passive high-pass filter will require reverse polarity of front and rear drivers - and I don't think this will work properly with regard the mutual loading of the center horn. I that case we would have to separate the two horns and that's another story and will require a complete redesign of the speaker. Another year's work! Best regards, Troels.


DTQWT built by Bertrand/Switzerland

Hi Troels,
I finished the DTQWT a couple of hours ago! I figured I would send you a quick note since I would not have been able to make them without your work so THANKS!

So far, I am enthusiastic ;) I might not be fully objective after so many hours working on them but they sound really great. It's hard to describe sounds with words but the speakers sound extremely stable and deep - if those adjectives make sense. I was listening to Gilberto Gil and Stan Getz and had to get something in the kitchen: suddenly it felt like Getz was playing in the living room ;) The stage picture is very clear and all instruments sound perfectly distinct.

I'm all very excited about this. I can now admit that I was a little nervous building speakers without having actually heard them. I started like planned for Easter. I did most of the work at my inlaws (my dad in law has a large workshop with many more tools than I have) which is why I finished so late. It took me about 80 hours to read and then plan (I decided to go for slightly modified cabs), and then about 100 / 150 hours to build. You were right on all your pieces of advice: it took me more time and more money than planned ;) but was worth it...

I still need to finish the cabs (laqueer etc.) but I wanted to test them first before going on. I'll send ou pictures then.

Again, a big warm thank you for sharing this like you do. It's been very exciting to build those speakers, I now look forward to long hours of musical pleasure!

Take care, Bertrand