Since about 10 years ago, he started to play full-size big ears. At first, he only had models in production, and later caught up with the chui (peng) old headphones. I also started to pay attention to some classic models that had been discontinued. Gradually discovered the fun, began to collect their own toss.
This process will inevitably encounter the old, a little bit of a problem with the headphones, each time itching can not help but take apart himself, try to repair a repair.
Gradually, after a few maintenance successes, the friends around us encountered a similar situation and would show it to me. Later my headphone fever road slowly drifted away. I found that repairing a pair of headphones now brought me more pleasure than I could hear from listening to the headphones themselves (because the more music they love The less you come.)
This time is a good friend's front page k240 monitor (the forum is generally referred to as k240m) has one side of the sound with the turn off intermittently (Imagine a weight I guess fast to 200 pounds of fat in order to listen to music to the neck to accommodate the screen of the headset) , I suspect that the internal connection line is broken, and I sent it to me.
The friend originally wanted to repair himself. As a result, the nameplate was not removed and shelved. The earphones are like this to me:
Remove the earmuffs, remove the filter cotton, see the three blue and white acoustical friction device, the front page properly. (The front page is blue and white, and the second version is black and white. The new version only has tuning holes covered by filter paper; the front page sounds best.)
Plug in the iron and preheat it. Unscrew the slotted screw in the middle of Fig. 2 to expose the head beam holder and the connecting cable extending from the unit. The multimeter (the table is a bit low, do not spray) test, normal reading, indicating that the unit is no problem.
Remove the copper screws fixing the head beam and weld the connection wires.
Separate the back cover from the unit frame.
It can be seen that the position of the connection line near the unit has been broken, and the problem is really there. In addition, the internal tuning cotton has been weathered and crushed.
Every component near the headphone unit is closely related to the tuning. Friends also expected that the old earphones 35 years ago must be inside. Therefore, they bought a headset of other models of the same series in production. It is necessary to replace the part.
Take out this organ donated headphones k240 mk2.
Repeat the above steps to disassemble mk2.
It can be seen that the gap between the work of the mk2 and the front-end monitor is quite large. The unit has a strong sense of plastic, and only one layer of cheap chemical fiber cloth is covered on the tuning hole. This material is even more shrinking than the final monitor.
Remove the tuned cotton and transplant it to the monitor. By the way, connect the broken wire.
Cover the peripheral ring cover.
Repeat the above actions to replace both sides of the filter cotton and restore it.
When preparing to go back, it was found that the head of the monitor was loose and stiff. (Old on the left, new on the right).
Put on new
Reverse the above steps and reinstall the headset.
Then put back the protective cover and nameplate, and you're done.
There should be an as-built drawing that was just restored. I know this map is very important to this article, but I forgot to take it.
Bring it to the company the next day and put it together with my own headphones of the same version.
Put on the system supervisor's system (CD is b&o antiquity machine x1, the amp is the domestic imitation little hedgehog)
Contrast this to listening, the earphone after maintenance is more lively and luster than my own voice, 240m sound is very light and restraint, it sounds a bit not tired. And I am 240m because the earmuffs, filter cotton and cotton tuner are older than friends, so the sound is more depressing, more plain, the sound is not as good as the three-dimensional friend.
The T90 on the left is clearly a tragedy under this system.
The 65th anniversary of the right-hand k702 is indeed a flagship of conscience, and the sound is full without losing the charm. If the quality of 240m is not enough, it cannot be compared to the quality of sound.
However, 240m also has other headphones can not be replaced, such as its midrange, because the inverting connection, 240m IF texture and positive phase wiring headset is very different, resulting in it when listening to vocal and classical strings will be a very unique Listening, restrained and restrained, warm and listenable.
The above is the whole process of giving big health care to a headset 35 years ago. Thank you
Finally add a few words. Most of the old earphones on the quality of words with the current position of the same positioning headset gap is very obvious, do not understand the best players do not read a few pieces of poison on the blind pit. Most old headphones are not worth collecting, especially non-flagship models.
Private thought to play the old headphones real fun, one is to understand the history of old headphones, such as I have been very interested in the past two years of Baia in the early 90s to mid-(Bai heyday) two generations of four main products dt801/901, Dt811/911, because the factory fire production line was destroyed, so there is very little in the world, of which the highest specification dt911 is very precious, but also by some senior Baia players as the highest peak in Baia. I'm a Baia party who played from dt231. I really want to see it when I meet.
Another fun is to experience the different understandings and orientations of sounds of designers of different generations and brands. For example, in early Senhai, the tuning was very much like the akg of his contemporaries (when Senhai was a junior compared to Akg and Baia). Hd520, 540 these models sound fresh and elegant, and later embarked on a 580 600 that kind of imposing way. The Beyerdynamic's old machine has always been unique in the tuning style, and it seems that it has been using earphones as audio analysis instruments, and it always insists on restoring true sounds. One of my favorites, version 03 dt880 is the final work of Baia's previous generation of designers before retirement. High-frequency fine-grained, dense and grainy, medium-frequency and low-frequency direct white, fast response, and simple and simple form design, the entire product is fresh and refined from the inside to the outside, and the person you like is sure to love it. .
End of the article
Hydraulic Light Tower
A hydraulic light tower is a portable lighting system that uses hydraulics to extend a tower and provide illumination in various settings. It is commonly used in construction sites, road works, emergency response situations, and outdoor events.The hydraulic light tower consists of a telescopic mast that can be raised and lowered using hydraulic cylinders. The mast is typically made of strong and lightweight materials such as aluminum or steel. At the top of the mast, there are multiple light fixtures that can be adjusted to provide 360-degree illumination.
The hydraulic system of the light tower is powered by a hydraulic pump that is usually driven by a diesel engine. The pump supplies hydraulic fluid to the cylinders, allowing the mast to be extended and retracted smoothly. The height of the mast can be adjusted to meet specific lighting requirements, with some models capable of reaching heights of up to 30 feet or more.
The light fixtures on the tower are usually high-intensity discharge (HID) lamps or LED lights, which provide bright and efficient illumination. These lights can be rotated, tilted, or adjusted to focus the light in specific directions. Some models also come with features such as automatic light sensors, timers, and remote control capabilities.
Hydraulic Light Tower,Led Lamp Light Tower,Mobile Lighting Tower Led,Mobile Led Light Tower
Grandwatt Electric Corp. , https://www.grandwattelectric.com