Because the Signature DJ and the HFI-580 use the same construction and you can get spare parts of ultrasone headphones (I live in europe), I decided to replace the drivers with the SigDj drivers to get the sound of the SigDj in the casing of the HFI-580.
The drivers of both headphones look exactly the same, so I was at first not sure if Synthax (the only place were I could find Ultrasone drivers sold, but ultrasone should sell spare parts, too) sell the 580 drivers at do different price points, but this is not the case. I think Ultrasone just took a better magnet for the drivers and changed some specifications. Ultrasone said, that they developed a new driver for the SigDj, so it has in some point to be different.
But overall the SigDj is a development from the 580 and I decided do replace the drivers to see if it works. I hadn’t much to loos and for this price I sought it is worth a dry.
So I ordered the drivers. And as expected the look exactly the same as the 580s.
I first pulled the pads from the headphone, open them, and desoldered the cable from one side, so I had a reference to put the new driver right in place.
Now it comes the tricky part: to pull the old driver out. The driver is clued in and the fence around the driver might break. I took a small knife and with its help I was able to pull the driver out. After that, half of the driver was still on the fence, enough to hold the new driver in place.
After that I soldered the new cable on the driver. Then I did the same with the other side. To try if it was working I but some music on the headphones, and indeed, it worked. After I put everything back in place, I played them in over night with some pink noise.
Besides the driver change I replaced the head pad with the headband padding from the HD 650 and put some rubber tubing under the ear pads to get some extra space for the ears. Also I cut out some circles from the velvet transportation bag that came with the HFI-580 and stitched it on my pads to become like a velour pads feeling.
First, I never heard some original SigDjs. The 580 are the most expensive cans I owned and I have only the HFI-450 as reference. I also have only a Sound Blaster X-Fi Surround 5.1 Pro as sound card with my laptop and a teac mp-275 as mp3 player and a iphone 4s. But the headphones are easy to drive and even on the mp-275 I get a decent sound.
The sound of the SigDjs are only as good as the music is you are playing. If the quality is good it will sound good, or slightly better. If it is bad, it will sound bad, but it will not sound worse (if the source is worse, it will sound worse of course).
The main improvement to the 580s are the highs. If in the music are bright highs, you get bright highs. With the 580s the highs are always are a little bit sharp and with hiss and not suited for all music genres. With the new drivers this improved in a big way. Maybe due to the higher resolution the sound have. I can now turn on music much louder without becoming sharp sounds and sibilance. That doesn’t mean that if there is sibilance recorded, that I don't get sibilance (I do).
The bass improved too. Mainly the sub bass. But overall it has more details and textures in the bass. If it has bass in the music, the bass is present, if not, you wont here any bass at all. So again, it is only that playing what is in the music.
Overall the sound improved in every way, less sibilance in highs, better and more bass, maybe a bit warmer overall as the 580.
I think it is worth the price of the new drivers, but I don't knew if I would spend the full price of a new SigDj. Maybe I just haven't enough experience with more expensive headphones or need a better audio setup to do the SigDjs justice. It is a bit difficult for newbies like me to expect what they get and not to be disappointed (I'm not, just saying). I'm very happy with my cans as they sound now, and I can't imagine any other to move upwards (OK, maybe the TH-900).
Edited by Hans Waider - 1/29/14 at 8:29am