Several LTS Speakers over the years have been presented as self-construction projects in the Music & Sound-publication. Here's a brief presentation of the various LTS-speakers and their backgrounds.:
The speakers LTS-F1, S1 and S2
The year 1997 Ingvar Öhman designed the first LTS speaker for sound technological society's behalf. It developed into three versions; a full registry system and two top systems. The latter is intended to be supplemented by subwoofers, for instance LTS-subwoofers with active crossovers at 80Hz with a high quality filter.
These three models use the same type of elements but in different configurations. Bas-mid-range element is an 8-inch elements that are special produced by the Seas of Audio Technology Association specifications (LTS). It is based on a standard element but has a much longer stroke and a different design of the moving parts for the elimination of the resonances in the registry by default element exhibit. Tweeter is a selected standard element of Seas; H534, which also is used in some of NHT's more expensive models and that is a very nice element regardless of price. This modified for better circulation and lower distortion in a simple way for the use of LTS-speakers.
Full Index System F1 uses a tuned bassreflex box of about 52 liters with a woofer and a tweeter. The small top system S1 has the same comfiguration as F1, but uses a sealed box of about 18 liters. The top-S2 system using two woofers in D'Appolitokonfiguration, that is a woofer - tweeter - woofer in a closed box of 36 liters. Configuration provides a more limited distribution in the vertical, which may be useful in some contexts, as it reduces reflections from the floor and ceiling. S2 gives a doubling of sound pressure capacity and sensitivity towards the S1 and F1.
Pictures of F1, S1 and S2
In addition to these three basic variants, was developed a few variants of S2, which placed the basis elements in different ways with the variation of the spread characteristics of adapting to different environments and to home theater setup.
An alternative filter design was also developed for the adjustment of F1, S1 and S2 to monitor listening.
Detailed speaker theory, dimensional rings and building descriptions for LTS-F1, S1 and S2 is published in Music & Sound No 2-97. Measurements and alternative designs presented in the Music & Sound No 3-97, No. 4-97 and 1-98 No. Description of the speakers can also be ordered as reprints through the HiFi-Kit.
LTS-3v-f1 / LTS-3v-f4 with multiple subwoofers
Many were very satisfied with the sound of these relatively cheap speakers. Curiosity about what could be achieved with a bigger budget was raised and soon came requests for developing a more refined and more expensive design. This was started to "LTS three-way".
In a three-way speaker elements need not cover an equally large frequency range, so some difficult to reconcile demands of each element is reduced and they can be more specialized for their task. In its basic design has LTS 3v-f1 an 8-inch bass element on the back and a 6.5-inch mid-bass element, and a 1-inch aluminum tweeter. With this placement of the elements it exploits the rear wall and floor in support of the bass freqency range, while mid-range and treble will be further away from the walls and floor, which reduces reflections. The filtering between those elements is done in a way that reduces the interference from walls in the upper bass lower mid-range. This makes the interfernce in this register to be significantly less than for a regular speaker at a meter out from the back wall.
Image of LTS 3v-f1
LTS-3v-f1 can be upgraded with additional three bass elements (a total of 4 pieces on the back of the box with two on the inside and two on the outside), to achieve a significant distortion reduction in the base and also increase the sound pressure of resources by a factor of two = sound effect with a factor of four (ie 6dB).
Image of LTS-f3-f4 with 4 basses
Bass element is specially built to meet the high demands of low distortion, ability to handle high acoustic loads and a consistent behavior for weak as well as strong music signals. The latter can be difficult to ahcieve, but is an important feature of natural music reproduction. The mi8d-range is based on a 6.5-inch Seas elements with changes to achieve a more balanced frequncty response and ability to reproduce higher sound pressure with lower distortion. Tweeter is similar to the one used in the LTS F1 and others, where the magnetic shielding is the most significant change to the H534.
Photos of the elements
Not only the treble, but also mid-range element is shielded for use near a TV and, consequently, there is also center speaker as well as rear speakers, for the completion of the speakers at home. The Center can be built in two versions with different sound pressure ability. Rear speakers are biased and are suitable for use parallel to a greater number for a more comprehensive and immersive rear audio sphere.
Photos of the center speaker and surround speakers
Two small two-way speakers have also been developed. In principle, it is a LTS-F3, but the bass is on the backside and with 6.5 "bass.mid in a 13 liter high bassreflex box.
Image of LTS-2V-f1
Basmodulerna LTS-B1, B2 and B4
First came basmodulerna B1, B2 and B4, which was presented in Music & Sound No 4-96. These were based on the well-designed NHT 1259, which is used in prestigious model NHT 3.3. The element was for his time an extremely long throw and a behavior that even today hardly is matched by elements available for the home builder. Unfortunately there is no element longer, but can be found on the secondhand market.
NHT-1259
Te subwoofer can be built in a number of different styles, depending on the desired sound pressure capability and capacity to suppress standing waves in the room. One can choose between three different sizes with 1,2 or 4 elements per box. The box can also be built in two different forms, one compact (B1 and B2) and a more elongated and high (B1h and B2h). The basic design is an optimally tuned closed box but bassreflex tuned box were also presented for those who wish additional capacity in the lowest octave.
With some of the more capable subwoofer modules, for example, four B2h or two B4h in the corners of the room, it is possible to achieve an articulation of basregistret which are difficult to buy ready built for the money.
Image of basmodulen B1
Specifications:
Model
LTS-F1
LTS-S1
LTS-S2
LTS-3v-f1
LTS-3v-f4
Principle
Closed Closed bass reflex enclosure box bass reflex bass reflex
Bas
1st to 21-LTS 1st to 21-LTS 2st to 21-LTS 1st Cx21-LTS
4st Cx21-LTS
Mellanregister
see above, see above, see above Px17-LTS
Px17-LTS
Treble
Seas H534 Seas H534 Seas H534 Ax2.5-LTS
Ax2.5-LTS
Frequency
2200Hz
2200Hz
2200Hz
170/2950
Hz
170/2950
Hz
Frequency Range
DIN (-8dB)
19-23000
Hz
46-23000
Hz
46-23000
Hz
19-23000
Hz
19-23000
Hz
Rated output
100 W
100 W
200 W
200 W
600 W
Sensitivity
87dB
87dB
93dB
88dB
88dB
Impedance
8 ohm
8 ohm
4 ohm
6 ohms
6ohm
Exterior
B x D x H [cm]
26x100x30
26x48x22.7
26x64x31.6
26x100x43
26x100x43
Model
LTS-2V-f1
LTS-2V-s1
LTS-2V-v1
LTS-2V-m1
LTS-2V-m2
Principle
Closed Closed bass reflex enclosure box bass reflex bass reflex
Bas-mreg
Px17-LTS Px17-LTS Px17-LTS Px17-LTS Px17-LTS
Treble
Ax2.5-Ax2.5 LTS-LTS Ax2.5-Ax2.5 LTS-LTS-LTS Ax2.5
Deln.frekvens
2950 Hz
2950 Hz
2950 Hz
2950Hz
2950Hz
Frequency.
DIN (-8dB)
40-23000
Hz
70-23000
Hz
Not given
40-23000
Hz
40-23000
Hz
Rated output
80 W
80 W
80 W
80 W
160 W
Sensitivity
88 88 88 88 92
Impedance
8 ohms 8 ohms 8 ohms 8 ohms, 4 ohm
Exterior
WxHxD [cm]
21x40x25
21x32x15.2
45.5x29.5x
(14.5 deepest)
(45 below, 12.2 up)
x30x23.7
(71 below, 38.2 up) x30x23.7
Model
LTS-b1
LTS b1h
LTS-b2
LTS b2h
LTS-b4
Principle
Closed or underavstämd
bass reflex
See b1
See b1 See b1 See b1
Basel Mentales
NHT1259
See b1 See b1 See b1 See b1
Exterior
WxHxD [cm]
50x50x61
26x100x61
45x106x61
26x200x61
47x200x61
Lower
frequency
in place
Ca 15Hz
See b1 See b1 See b1 See b1
Rated output
150W
150W
300W
300W
600W