DTQWT

In Mai 2011 a friend ( Joffrey from Maastricht) of me asked me to build a pair of DTQWT loudspeakers for him. He asked me if I could build a pair of these speakers using solid French Oak and Oak venered MDF panels. As I build the TQWT speakers for myself in the past (also published on this site) I was a little curious about the sound of this bigger brother. My self made carport was just finished and my hands were free for a new project....So why not giving it a try:) So I agreed and in no time the electronic parts were ordered at Jantzen Audio Denmark.

In the mean time I started with the cabinet's, so here is a impression of how I build them:)

I always start with one side panel to be build, and then add the internal bracing and/or TL panels to this panel. Always use cookies and try to keep things rectangular ( 90 degrees ). This is of high importance to assure further fits correctly. The MDF I use is double venered material so called A/B panels. A side=first quality venered, B side=2nd quality venered. Both sides venered MDF has some advantages because it won't bend under moisture influences. Both sides have equal characteristics, and therefore they addept the same amount of humidity.

To accomplish some force in the middle of the panel, just were the internal bracing is placed, I use a sort of bridge from a strong piece of wood, see picture right. Picture below shows damping material on the front side of the cabinets.

The large driver holes on the back are made, using my custom made router guide (Ebay Germany) which gives me much pleasure! Even very small circles can be made with this device.

The MDF TL-panels have to be flushed to the side panels. I did this by using my router, I think this is the most easy way. Sanding will be less accurate I guess sanding will be less accurate.

The second side panel has been marked using a pencil, and the cookie slots are cutted. This should be done very precisely to avoid mismatch. I sand the panel to remove dirt and splinters.

DTQWT by Troels Gravesen

After some sanding work (it comes with the wood worker), the drivers are pre-fitted, and some pictures are made. Joffrey decided to do the elctrical part himself. So they are ready for leaving my house:)

These ar actually no smal loudspeakers, so decide if you're wife will be happy with them, before start with building them:)

But as size does matter in loudspeaker land, you will be rewarded.

Next pictures (below) are taken at Joffrey's house, in Maastricht.

I visit Joffrey on his invitation in oktober 2011, when he completed the speakers with the X-overs and wiring. He also gave them a nice clear laque coat, which made the beautiful Oak grain structure visible. Joffrey play's the speakers on his DIY class-A F5 from Nelson Pass. Delivering some 25W RMS max. these speakers come to live! Joffrey I wish you many HIFI listening hours, with this great design speakers.

Also many thanks to our speaker designer Troels Gravesen, who let us join his great designs, and make it possible for us to join his adventures:)

They are extremely natural with an extreme good resolution which is e.g. striking in complex music like orchestra with choir, everything is separately to be followed. Piano music is a revelation, a grand piano sounds like a grand piano, full bodied. High frequencies are very sweet and also with a good resolution and never fatiguing. I have heard better resolving tweeters but the coherence in this speaker is very good. I use the 2.7 ohm of the 3 optional series resistors. I tried all three of them but the effect of lowering the resistor in my opinion is that high mid frequencies get more aggressive. I also tried a bypass cap, a Vishay Roederstein and ERO MKP1837-0,01uF/160Vdc +- 1% and a Styroflex 0,0068uF / 160Vdc +- 2,5%. I know the controversy about these bypass caps esp. in combination with the already very good silver cap, but after trying I want them to stay. In conclusion the DTQWT's are very musical speakers with a perfect tonal balance from bottom to end.

Review DTQWT (by Joffrey Klein Ovink)

Giving a description of the sound of a loudspeaker set is always very subjective but I will try to give some hints about the qualities of the DTQWT. The DTQWT’s have now a break-in time of at least 100 hrs. as Troels Gravesen advices. And indeed the sound has changed during this period, low frequencies slowly improved, gained more tightness and depth. If you expect this loudspeaker to be a disco subwoofer bass slamming one, you are wrong. In correct placement, the bass is present, fast, but never too much .