[IPodPJ]

I received mine too but don't have a scanner here at home. Mine is much closer to kelvinz than it is to vai-777.

The certificate itself, which is custom digital printed with our names and serial numbers on it at the top, includes this bit of text:

"Standardized for High Performance

The curve shown below is the result of a comparison between the perceived volume
and the measured SPL. The goal of such a comparison is to measure the necessarily
subjective elements of high sound quality in a standardizable way.

The reference measurement on which it is based takes several days and involves no
fewer than 16 acoustics experts; it takes over 10 hours just to calibrate the sound field.
Only by going to these extraordinary lengths can we keep our promise:
HD 800 -- Crafted for perfection.

(I will provide the graph in numbers (as close as possible to the nearest 0.1 dB) so you can see what the curve is: )

Your Individual Diffuse Field Frequency Response
HD800 silver. Serial no.: 00685. Loudness diffuse field - Frequency response.

100 Hz -------- 3.2 dB
125 Hz -------- 3 dB
150 Hz -------- 2.8 dB
200 Hz -------- 2.6 dB
250 Hz -------- 1.4 dB
300 Hz -------- 2.6 dB
400 Hz -------- 2.9 dB
500 Hz -------- 2.7 dB
600 Hz -------- 2.6 dB
800 Hz -------- 2.3 dB
1 kHz --------- 2.6 dB
1.2 kHz ------- 3 dB
1.5 kHz ------- 3.25 dB
2 kHz --------- 2.5 dB
2.5 kHz ------- 1.4 dB
3 kHz --------- 0.3 dB
4 kHz --------- 1.1 dB
5 kHz --------- 1.6 dB
6 kHz --------- 3.5 dB
8 kHz --------- 2.2 dB
10 kHz -------- 2.8 dB
12 kHz -------- 2.5 dB"

Here is what the included letter says:

"Dear Mr. --------

Thank you for your interest in an individual frequency response for your HD 800.
We are pleased to be able to send you your own personal copy today.

The enclosed certificate documents just one of numerous quality tests conducted to
ensure that all HD 800 headphones meet our very strict standards for sound reproduction
and sound quality.

But this test is undoubtedly one of the most impressive: It is based on reference
measurements taken over several days by no fewer than 16 of our best acousticians.
We have recorded the results just for you.

We hope you continue to enjoy your very own piece of hand-made perfection!

Yours sincerely,

Maurice Quarre
Product Manager
Home Audio

Axel Grell
Senior Acoustical Engineer
Headphones"


But here's the most interesting thing! On the frequency response graph, on the top next to the serial number it says "HD800 silver." Does this imply that any color other than silver is going to be released? If not, why even mention it?

 

[Drumonron]

Hi folks, I also just received my frequency response graph and will try to post pics of it tomorrow.

 

[Beagle]

Quote:

Originally Posted by robm321 /img/forum/go_quote.gif Me too. That's very odd to not do the 20 to 20K

I guess it's kinda like when you get a bag of pretzels and it gives you the sodium and calorie values for....2 pretzels.

 

[feifan]

Quote:

Originally Posted by IPodPJ /img/forum/go_quote.gif 100 Hz -------- 3.2 dB 125 Hz -------- 3 dB 150 Hz -------- 2.8 dB 200 Hz -------- 2.6 dB 250 Hz -------- 1.4 dB 300 Hz -------- 2.6 dB 400 Hz -------- 2.9 dB 500 Hz -------- 2.7 dB 600 Hz -------- 2.6 dB 800 Hz -------- 2.3 dB 1 kHz --------- 2.6 dB 1.2 kHz ------- 3 dB 1.5 kHz ------- 3.25 dB 2 kHz --------- 2.5 dB 2.5 kHz ------- 1.4 dB 3 kHz --------- 0.3 dB 4 kHz --------- 1.1 dB 5 kHz --------- 1.6 dB 6 kHz --------- 3.5 dB 8 kHz --------- 2.2 dB 10 kHz -------- 2.8 dB 12 kHz -------- 2.5 dB

Wow, it's cool to see it this way, too! The numbers seem to stand still while the wave appears to keep moving. Should we be concerned about the 0.3 dB dip at 3kHz?

 

[IPodPJ]

Mine and kelvinz are different than Vai-777. Have you noticed that ours has increments of every 2.5 dB while Vai-777 is shown in increments of 3 dB?

 

[b0dhi]

Quote:

The curve shown below is the result of a comparison between the perceived volume and the measured SPL. The goal of such a comparison is to measure the necessarily subjective elements of high sound quality in a standardizable way.

This seems to be a much better way of measuring frequency response, but it can't be compared directly to SPL measurements that you see elsewhere. I'd like to know which perceived volume curve Senn is using. IEEE?

 

[TheMarchingMule]

Quote:

Originally Posted by pearljam5000 /img/forum/go_quote.gif Humm it says "HD800 Silver" i think they are going to make another color

I thought the exact same thing when I saw that.

 

[squirt]

silly question: how did you obtain the fr certificate? in the hd-800 manual it states you can view your hd800 fr chart the entering the ser.no at sennehiser.com but i can't figure out where on the site you enter the ser.no.
regards

 

[Currawong]

Interesting that serial number 517 has a more noticeable peak at 6k compared to the OP's pair. I'm starting to wonder, as I wait for my FR graph to arrive, if my suggestion that there are distinct differences in sound between batches is about to be proved correct.

I have to say though, the scale and limit of the graph is rather odd and not very helpful.

 

[xenithon]

Obviously no hard feeling to the OP and others in the thread who received their graphs, but this is truly - as they say - adding insult to injury for all of those (myself included) still waiting for Sennheiser to actually deliver the HD800.

 

[Skylab]

Quote:

Originally Posted by Currawong /img/forum/go_quote.gif Interesting that serial number 517 has a more noticeable peak at 6k compared to the OP's pair. I'm starting to wonder, as I wait for my FR graph to arrive, if my suggestion that there are distinct differences in sound between batches is about to be proved correct.

Indeed, this is VERY interesting to me - considering the serial number of the pair I have is 590. There is no doubt that the peak in the treble response of pair 517 belonging to Kelvinz will be audible, and very likely in exactly the ways I have described. What is interesting is that Vai-777's graph does not contain the same peak.

It's way too early to call this a trend, but I hope more people would post their curves when they receive them, because this might indeed shed some interesting light on the difference of opinion that head-fiers seem to have over these cans.

 

[k3oxkjo]

Quote:

Originally Posted by b0dhi /img/forum/go_quote.gif This seems to be a much better way of measuring frequency response, but it can't be compared directly to SPL measurements that you see elsewhere. I'd like to know which perceived volume curve Senn is using. IEEE?

It uses Diffuse Field EQ curve. Read post 9 in this thread for more info.

 

[pabbi1]

Quote:

Originally Posted by Skylab /img/forum/go_quote.gif It's way too early to call this a trend, but I hope more people would post their curves when they receive them, because this might indeed shed some interesting light on the difference of opinion that head-fiers seem to have over these cans.

Far more interesting is when folks start investigating trades of hd800 for the frequency curves that better reflect their preference, and, if certain phones develop a higher $$$$ demand due to their specs? Quite interesting indeed.

 

[Karlosak]

I too received my Sennheiser HD800 certificate today, probably I'm the first in Europe

:



And here is the frequency response itself:

No 6K treble peak there. It's no surprise I find the highs perfect

.

 

[DoYouRight]

Does country of order affect this treble spike trend at all? Wondering where to order mine?