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pronounced: X-T-six-twelve |
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developed by Kurt Hansen & Robert GS with our active amplifier Coolback II 600 |
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Vifa XT25BG06-04 Ring radiator Tweeter * 4Ω * 92dB * 2500Hz-25kHz * 60W The tweeter XT25BG06-04 is a patented design called ring radiator and it has an extended flat response. It is performing its best over 3kHz when a system has higher SPL capability - this system definitely has a high max SPL without any compromises. |
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Peerless HDS Exclusive 6˝" 6˝" Nomex cone * 8Ω * 88dB * Fs=42Hz * 60W The mid-range Peerless 6,5” HDS Exclusive presents a very crystal clear sound. The HDS has very low distortion, smooth response with a mild brakeup and near flat impedance, which is a result of a great motor design utilizing copper. The mid driver has the “lowest” max SPL capability and we decided to cross it a bit higher than normal for a driver of this size to protect from too high power and excursion. |
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Peerless XXLS 12" 12" Aluminium cone * 4Ω * 91dB * Fs=19Hz * 400W The bass is a really nice woofer – often used in stand alone subwoofers in the range from 20Hz to around 100Hz. In the XT612 we utilize its flat response for a higher crossover point 300Hz in a ported volume of 100 litres – the port is tuned to 25Hz, which gives the loudspeaker capability of reproduce the atmosphere of the recording room - when the sound engineer has done a proper job. |
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XT612 techincal drawing in PDF format:  The shape and stiffening of the box gives less square areas and the different materials gives different resonances within the box. The construction of the front with both 19mm MDF and solid kitchen worktop wood gives the drivers a rigid base for performing their best. The rest of the box is constructed in 22mm MDF. You often find constructions that includes the possibility of sand fill to give the box more weight = better ratio between moving mass and non moving mass. We have chosen to use the MDF that we already have left over for the port which adds weight to the construction and forms a solid barrier inside the bass volume. Here you normally see a plastic tube which doesn’t weigh much and aren’t that solid. The Coolback also adds weight and is yet another material. The total weight of each box is actually 60kg. There are other benefits of putting the amplifiers inside the loudspeaker. Short speaker cables for one and then there is the visual aspect. You do not have a stack of amplifiers to place somewhere because they are integrated in the box. This leads to a higher WAF (Wife Acceptance Factor) and you might even be allowed to have a bigger loudspeaker like the XT612 exactly because of this. Sorry for assuming that only men are building loudspeakers and I could provoke a bit more by saying: “The size of the loudspeaker shows how much you actually have to say at home!” - again assuming that it’s a mans thing the interest of music and sound. Everything really adds up when active amplification is used – giving total control and lots of power directly into the drivers AND still having sonic excellence, headroom and dynamic range. A lot of loudspeaker constructions simply lack the ability to perform a well recorded piece of music because they are not full-range and / or has insufficient sound pressure levels. The performance of the bass is often overseen, but bass is often the key to success. The right tuning in the room by controlling the room modes also gives a controlled bass response. If you have an uncontrolled room mode you will have a frequency in the bass that will “stay” in the room for too long - for example giving a bass guitar an uneven nature when the string / node is hit. The tuning of the bass affect the tonal balance of the loudspeaker and often a speaker can sound “hard” because of lack of bass level or width. You often see that people choose less bass response or rather “no” response to avoid the “singing” room modes which leads to a “hard” sound without atmosphere reproduction. You could move the speaker outside and experience what a cheap trick it is – no bass gain from the room and here you really lack bass response and the music will be dull and it will lack the abillity to be alive.
- all done at Kurt's work shop, thanks!
The edges of both the box and front between them has have a 45° cut for nicer looks
The Coolback fits perfectly in the box and the boxes are ready for paint
(like - SD Sonic Design) has to be at least 25mm. The Coolback is mounted before the drivers, because it is possible to have the box lying on the back when the drivers will be mounted.
The crossover points are 250Hz Linkwitz-Riley 24dB/octave and 3kHz Linkwitz-Riley 48dB/octave. For protection of the bass a HighPass filter have been set at 20Hz type 8.order Butterworth. Here is the same setup of the DCN23 in XOverWizard version: XT612_messe.xow You might think it should be flat when the possibility are within reach of the DCN23 and you could do that - just download the setup and go ahead. Here is the "old" software if you haven't already got it: XOverWizard . I decided to set it up as mentioned above and in many High-End systems some of the same choices have been made. ...or you can add your personal taste The decision is totally yours ! |
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XT612 |
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