DTQWT mkII, built by Rolando, Argentina
Copyright 2017 © Troels Gravesen

Hello troels
Begin the construction of the DtqwtII at the beginning of the year 2015 and I have put it into operation at the beginning of the current year. I did it without haste and without pause, in my spare time, since I already had a fairly respectable music system and since I was very young I was always involved in this subject that we are so passionate about, I did not have the anxiety of youth .
In addition I had a goal, not to buy tools (presses) that later I would not use more. So I decided to overcome this inconvenience by appealing to my somewhat rusty knowledge of carpentry and mechanics, but they are not forgotten.
Finally, the result has been expected. The front and rear panels are 30 mm and everything has been glued with dowels .
I still have to build the grids for the cabinets, which I will place mainly for driver protection, and also make bases with wheels, to allow easy movement inside the living room, because they are really heavy ! Which is very good, of course.
The sound of DtqwtII is very good, detailed, the different instruments are heard natural, without colorations, and as you mentioned it, there is no distortion even at high volumes.
I only noticed that, although there was no lack of extension in the first octaves, a little more sound pressure in them was desirable. So I've done some experiments and, to my surprise, I now have the sound I like in bass. It's fast, there's no boomy, and it's both solid and blunt.
I imagine it may be something similar to the passage of model two to three, which you yourself perceived.
For this I have used a modest bi-amplification, influenced by his article to the point. I have used an amplifier that I built many years ago but still works properly. I've used the Eminence 2510 section crossover, leaving one of the drivers as a passive radiator and plugging in a vintage JBL instead. I have not found information on your page about the cutoff frequency of the first order filter that you designed and applied to this section, I would like to ask you about it. But the integration is very good.
It is my intention anyway to use in the future a board plate amplifier and build a dedicated horn speaker, with a great surface subwofer driver, I am thinking 1x 18 or 1x 21 inches, I still do not decide. From what I'm sure, is that after this experiment I will not return without a dedicated subwoofer.
I thought maybe this might interest somebody, so I attach the respective links, of course you can have the photos you want.
I greet you and I am very grateful for this project. He is a great speaker and was very well invested every second I used in his construction.