CHANGSTAR: Audiophile Headphone Reviews and Early 90s Style BBS

Lobby => Headphone Measurements => Topic started by: Marvey on December 28, 2011, 11:46:58 PM

Title: AKG K240DF Frequency Response and CSD Waterfall Plots (RexAetera Modded)
Post by: Marvey on December 28, 2011, 11:46:58 PM
AKG K240DF Frequency Response and CSD Waterfall Plots.

These were modded by Rex. I'll let him explain what he did. They sounded pretty good. Keep in mind the -40db floors show more that what most people can hear. If I sound partial to these, it's because I am. This is a warm sounding headphone with some slight treble emphasis. Maybe what I would call a gentle U-curve - done right.

Compare to the Sextetts: http://www.changstar.com/index.php/topic,68.0.html (http://www.changstar.com/index.php/topic,68.0.html)
Title: Re: AKG K240DF Frequency Response and CSD Waterfall Plots (RexAetera Modded)
Post by: RexAeterna on December 29, 2011, 01:22:15 AM
is it me or the waterfall plots are not looking so hot? i have idea how to tell. i didn't really mod, mod them really. i have them recabled with 18awg silver/copper wiring and terminated to 4-pin XLR. the enclosure inside is empty cause i didn't have replacement foam to go inside when i cleaned them and just used speaker cloth over the driver to protect it. my mind is blown though like the sextett results. did you try hooking them up to speaker outputs to test correct polarity cause when i wired them i accidentally made the silver wire the positive and copper negative. i think i remember getting more warm sound from them and less clarity when i ran them out of phase. can't conform it since i haven't used them for months.

i appreciate it though you going out your way to measure these. much appreciated!
Title: Re: AKG K240DF Frequency Response and CSD Waterfall Plots (RexAetera Modded)
Post by: rhythmdevils on December 29, 2011, 01:57:54 AM
Very cool.  So the driver is probably contributing to the substantial ringing in the K240 models, and the passive radiators aren't necessarily to blame (these don't have any, just damped vents in the baffle)

So Purrin, putting measurements aside which did your ears prefer?
Title: Re: AKG K240DF Frequency Response and CSD Waterfall Plots (RexAetera Modded)
Post by: RexAeterna on December 29, 2011, 03:00:57 AM
yea, they woven stitched baffles. my DF's though has no dampening inside really cause i realized when i went to rewire them the foam inside rotted away. i know the driver is different and lighter than the sextetts. also smaller than the sextetts from my observation when i took my older sextetts LP apart and looked at the the size and weight compared to the DF's. thing is it's weird. i liked my DF's and sextetts way more than my K601's and kinda used my DF's to help tune my fostex. also curious,where's the FR graph?
Title: Re: AKG K240DF Frequency Response and CSD Waterfall Plots (RexAetera Modded)
Post by: rhythmdevils on December 29, 2011, 05:57:43 AM
The foam isn't really damping (though it probably has some very subtle effect) it is simply mechanical to give them nice feel in the adjustment so the cups don't just hit plastic when they swivel, they have a springy feel.  Not going to change measurements much I don't think. 
Title: Re: AKG K240DF Frequency Response and CSD Waterfall Plots (RexAetera Modded)
Post by: RexAeterna on December 29, 2011, 06:05:59 AM
The foam isn't really damping (though it probably has some very subtle effect) it is simply mechanical to give them nice feel in the adjustment so the cups don't just hit plastic when they swivel, they have a springy feel.  Not going to change measurements much I don't think.

yea. your right. i was just mention there is nothing in there since i had to clean them out. i was gonna wait to rewire them before but when i checked inside to see how they were wired cause i was curious to see if they used the same 4-core wiring as the sextetts since emailing  AKG was no help the wires became loose so i was like 'what the heck'' and rewired them then. they were bare wired till i bought a 4-pin XLR jack for them recently before sending them out. i did notice once though when i tried cotton as a replacement for the foam it made them more congested sounding for some reason.

EDIT: also wonder if tried with 240 foam disc that was in my fostex? i didn't have spares at the time so i used speaker cloths instead to protect the drivers in the df and i know at least the foam discs in front of the driver made most of the difference and prevented it sounding too bright. i don't know though, maybe it's just me.
Title: Re: AKG K240DF Frequency Response and CSD Waterfall Plots (RexAetera Modded)
Post by: Marvey on December 29, 2011, 07:39:36 AM
They don't measure horribly. That ringing at 14K or whatever cannot be heard as something bad by most humans. The only problem spot is the ringing at 8kHz (which I did hear a little bit of.) Subjectively I felt these modded DF were a little bit more trebly than the K240EPs, so I have to say I liked the EP's better. They both sounded very similar to each other. FR graphs next...
Title: Re: AKG K240DF Frequency Response and CSD Waterfall Plots (RexAetera Modded)
Post by: RexAeterna on December 29, 2011, 08:06:08 AM
awesome! lucky you didn't hear my sextetts lp then if you thought the df's had some brightness the them :P. my LP's no matter what always sounded much brighter compared to any other akg i ever heard and can be annoying on lot of modern recordings.
Title: Re: AKG K240DF Frequency Response and CSD Waterfall Plots (RexAetera Modded)
Post by: RexAeterna on January 04, 2012, 02:51:35 AM
i still can't see these being on the warm side of things. i know lp's has slight hint of warmness in the midrange but that's only if you actually pay attention to it really cause they manage to have brightness to them as well with certain stuff. the DF's always sounded much more so to say ''clean'' sounding compared to rest of my akg headphones while sounding a bit dry sometimes as well.i guess i have too much inner fanboyism and loved them too much to hear it. i want to believe...i want to believe!
Title: Re: AKG K240DF Frequency Response and CSD Waterfall Plots (RexAetera Modded)
Post by: victor25 on January 11, 2012, 08:52:04 AM
I'm still looking for an AKG K240 DF, they seem really great headphones, hard to find though!
Title: Re: AKG K240DF Frequency Response and CSD Waterfall Plots (RexAetera Modded)
Post by: RexAeterna on January 11, 2012, 09:44:05 AM
there was couple on ebay last time i checked in good condition. guy seem to want around 135 for his he owned and the one he got from another household he's selling for 110. i lost out on owning a second pair of DF's that i could of had for 75 bucks, when i bought the fostex t50rp on an ebay bid, cause the guy selling the DF's lived like 10 minutes from me and i offered him some cash if he be willing to take it off the ebay listing and we can meet. i didn't get no response so i assumed no, so i bid and won the fostex(i won the fostex for 53 bucks). after that he responded ''if you go 75, deal!''. lol,wanted to punch myself cause i should been more patient but since i already owned one, no big deal and the fostex t50rp turned out much better then expected for me so i'm happy.