Hi everyone,
Although this is my first (long!) post I been roaming around head-fi for quite some years now, I just dont like to write that much (besides, English is not my native language, so excuse my poor writing)
I been into headphones for a little while and currently own: T90, DT880, HD600, TF10, XBA3 and MTP copper. When I bought the T90 I was also considering the HE500. I finally decided to buy the T90 because I like the DT880 over the HD600 (although I find the HD600 more "correct" I enjoy the DT880 more).
I find the T90 to also be very nice, detailed and "airy". In fact, these headphones are the only ones which have compelled me to write about. Nonetheless, when one is so close to "perfection" (although I know there is no thing as that!!) the small defects are more evident.
You know what Im talking about: the harshness on the sibilants is difficult to swallow!
IMO sibilants are a normal part of music and sound, so I dont mind hearing them. To be honest I dont really think that the harshness is entirely the T90s fault. In almost all the "clasically" recorded music (classic, instrumental, jazz and all non overproduced music) I find the T90 to be faultless. However, I also like to hear some pop music. I you hear pop music even in the most humble radio you will hear that the sibilants are overemphasized. I mean, I have heard live (non-amped) singing and the sibilants are not so noticeable (unless the singer is next to your ear!).
For the price and faultless performance of the T90, with more classically oriented recordings, I was expecting to be able to use them for all my music and not only for very select genres. Well, by looking at the web measurements and hearing to frequency swepts I can say that the highs peak is very localized and no too prominent. Normally, Im kind of a purist when it comes to using eqs and more so with these pricy headphones. However, this time I felt that a slight equalization was exactly what the doctor ordered.
Im used to using frequency analysis tools (at work) and equalizers (in my hobby) so after some while I got this setting for parametric peak eq. I compensated two high freq peaks and boosted a valley in the mids a little. I dont believe on violating the headphone basic character by using eq, so I made the lowest possible modifications to the nature of the T90s. I post it so you can try it for yourself. These can be used in most parametric eq like the rockbox equalizer (Im assuming they use 2nd order peak filters for the intermediate bands).
q1=4;
q2=4;
q3=3;
w1=4800hz;
w2=6800hz;
w3=9500hz;
k1=3dB;
k2=-2.5dB;
k3=-3.5dB;
The net effect is VERY slight, it is almost not noticeable at first. When hearing more carefully you will see that you can still hear all the sibilants and details but you wont feel that it is harsh. I rally like my T90s right now
. These peak filters are close so that the net effect compensates a little between them.
If you are inclined to it, here is the Matlab code to see the FR of these filters (remember to change the plot to Hz as it defaults to rad/s)
clear
q1=4;
q2=4;
q3=3;
w1=4800*2*pi;
w2=6800*2*pi;
w3=9500*2*pi;
k1=10^(3/20);
k2=10^(-2.5/20);
k3=10^(-3.5/20);
f1=1-(1-k1)*tf([w1/q1 0],[1 w1/q1 w1^2]);
f2=1-(1-k2)*tf([w2/q2 0],[1 w2/q2 w2^2]);
f3=1-(1-k3)*tf([w3/q3 0],[1 w3/q3 w3^2]);
w=logspace(log10(20*2*pi),log10(20e3*2*pi),1000);
bode(f1*f2*f3,w); grid
I really think that Beyerdynamic purposely made the T90s less than perfect, just look at the T1 FR vs the T90s. It is so close and the technology so similar that a perfected T90 would made the T1 useless. I havent had the opportunity to hear the T1, but many have stated that it is similar to the T90. Well, with this eq, I believe that it may be just a notch closer.
