Filter for HD700

[hbj]

Hi Solderdude, I was encouraged to ask you this question:

Have you ever made a filter for the Sennheiser HD700?

I bought it a while ago having used HD600 for 8 years previously.
To begin with I thought the HD700 was unbearably bright, but now it is not so bad anymore, it is mostly a problem with already bright recordings.
However I'd still be curious to hear of any improvement that could possibly be made to reduce the somewhat sharp treble a bit.

Thanks.

Best,
Henrik

[Solderdude]

You mean a passive in-line filter only addressing the same treble spike as the HD800 has ?
It seems to be pretty similar to the HD800 in tonal balance.

[hbj]

Hmm, yes it's something to handle the same treble spike.
I don't know if it's called a passive in-line filter - is that an electronic device, or do you mean a mod to put into each earcup of the HD700?
Thanks btw!

[Claus-DK]

It me who sent hbj here.
To put it short, he likes the HD700 in every aspect just not the spike in the treble which is a dealbreaker, so I thought of your filters and if you have had your hands on them ??

I guess an inline passive filter would be the easy solution, but if there is some mods in stock -------------we all love that

[hbj]

Thanks, Claus :)

[Solderdude]

Here you are:



When you have built it please report back.

The schematic can be downloaded as well: http://www.mediafire.com/view/gjde1ducg0ljd2l/HD700_peak-filter_schematic.pdf

[hbj]

Thank you very much, Solderdude.
I'll have to have someone build it for me though.
I'm wondering: What is the difference between using this and just lowering the 7kHz peak with EQ?

[Solderdude]

There is little difference when using parametric EQ where you can set the correct bandwidth, centre frequency and attenuation.
When using a graphic equalizer the filterband may be too wide or not at the correct frequency.
A disadvantage of digital EQ is possible distortions, side effects, uses extra processor power, can't do 'bitperfect' any more and you need to have a player that has the equalizer.

The passive filter can be used between any amp and the HD700 and doesn't add digital artefacts and allows for bit perfect playback.

You only need to (have it) build in a small box with a headphone socket + headphone plug.

It isn't complicated to build AND when you only have low output resistance amplifiers (Meier, the slee may have a higher output R) you don't even need R1, R2, C1, C2, L1, L2.

[Claus-DK]

Hi Frans
I bought some boards from you some years ago, are those the same boards ?? as you use now
If so I will see if I can find them and send them to Henrik..

[Solderdude]

The boards may have been crossfeed boards.

Don't have any filter boards.
These filters are best point to point wired or on experimenter board.