squarewaves for headphone measurements is it useful ?

[solderdude]

LOL - how true!

Try saying 'scheveningen' without giving away from which country you come from.
I have been told Dutch sounds 'melodic' of sorts with weird sounding words.

 

[solderdude]

Well I have examined many High rez files and few of them show anything significant other than noise above about 24 Khz.

I know...

A sweep can be used to look for the headphone resonances and get the impulse response. REW will do this.

That is part of the measurements I do ... using REW

As for NOS dacs, well if you are interested in noise that shouldnt be there ......

And get weird high frequency response and unintentional roll-off as a bonus.
Some peeps seem to like it... just not me.

 

[Krunok]

Try saying 'scheveningen' without giving away from which country you come from.
I have been told Dutch sounds 'melodic' of sorts with weird sounding words.

I know what you mean, but I have few Dutch friends and they told me they wouldn't guess my country when I was reading from one of their books.
It is melodic. Not as melodic as Italian, but still very melodic. And yes, Dutch words do sound a little weird to me, but not as weird as Swedish.

 

[Krunok]

As in 80 dB lower...

For digital files a squarewave is an illegal signal but for analog it is not.. Agreed it does not exist in nature but is not illegal nor should it be BW limted is the point I am getting at. It also shows ringing quite well but only about 20dB down or so.
It has its limits but is useful to me.

I agree that it can be useful, as long as the results are interpreted correctly.

 

[pwjazz]

Try saying 'scheveningen' without giving away from which country you come from.
I have been told Dutch sounds 'melodic' of sorts with weird sounding words.

Funny, I visited The Hague a long long time ago and I think popped over to Scheveningen too, but I can't remember how people pronounced it. I would imagine that like Schiphol, some people pronounce it with a bit of a guttural 'r' between the "Sch" and the vowel, but when I just looked up recordings online it seemed inconsistent. I don't know about Dutch, but in German we have a lot of regional dialects that vary to the point of being nearly mutually unintelligible *cough, Bavarian, cough*.

 

[pwjazz]

I think the HD800 is a MUCH better headphone in many aspects

I really need to find a way to listen to the HD800. Can you elaborate on these aspects a bit, in particular those that you find to be independent of frequency response? When I first got a pair of DT 1990s, they sounded "fast" and detailed to me, but when I EQ'd them and my LCD2C to a similar response, the difference largely (maybe even completely) disappeared. I won't claim to be the most discerning critical listener, so take that with a grain of salt.

 

[solderdude]

I agree that it can be useful, as long as the results are interpreted correctly.

That may be true for all test results

 

[solderdude]

Funny, I visited The Hague a long long time ago and I think popped over to Scheveningen too, but I can't remember how people pronounced it. I would imagine that like Schiphol, some people pronounce it with a bit of a guttural 'r' between the "Sch" and the vowel, but when I just looked up recordings online it seemed inconsistent. I don't know about Dutch, but in German we have a lot of regional dialects that vary to the point of being nearly mutually unintelligible *cough, Bavarian, cough*.

The Netherlands are very small and lots of dialects here. Some of them I really do not understand at all.

 

[solderdude]

I really need to find a way to listen to the HD800. Can you elaborate on these aspects a bit, in particular those that you find to be independent of frequency response? When I first got a pair of DT 1990s, they sounded "fast" and detailed to me, but when I EQ'd them and my LCD2C to a similar response, the difference largely (maybe even completely) disappeared. I won't claim to be the most discerning critical listener, so take that with a grain of salt.

Took me a while to hear it coming from an EQ'ed HD650.
When both are EQ'ed they have a similar tonal balance.
The differences lie mostly in the 'soundstage width'.
The HD650 is more 'narrow' and while no slouch cannot match the 'ease' one can pinpoint instruments with.
The HD800 is almost effortless where the HD650 still requires some 'straining'.
When coming from the HD650 (with EQ) I thought it was about the best there is.
With the HD800 (plus EQ) it is obviously not.

Stock, I find the HD650 'better' as the HD800 is too 'thin' and 'overly detailed/sharp'. The HD800S is 'slightly less 'extreme' but still too much for me. Both need EQ to me.

The DT1990's also are no slouch and just below the HD800 (when both EQ'ed). The treble on the DT1990 is a bit more piercing than the HD800.

 

[Krunok]

That may be true for all test results

When I said that I meant that you should be able to relate measurement results to what you hear when you listen to the headphones you are testing. If you can relate how sybilants are reproduced (or whatever it was) to the response to the square wave than it definitely makes sense to test that.

It also makes sense if you are measuring the amp response to square wave to test for stability, but if you cannot relate the parameter you are measuring to anything specific or you don't have an idea about where the audibility borderline lies than you shouldn't be measuring it.

 

[solderdude]

I have thoroughly investigated my own borders of audibility.
The deviations of all headphones are mostly magnitudes higher.

Linear scales (with amplitude) can be more revealing.
You can clearly see deviations that are below audibility thresholds.
That's what I like about those measurements.
Hard to 'see' 0.1dB on 5dB scales but easy to spot on linear scales.

 

[Sal1950]

Squarewaves useful?, Maybe, depends

The HD650 produce about the best squarewaves I have measured to date.

Now that doesn't surprise me as they're the best cans I've heard "to my bias", but admittedly I don't have a wide experience.

 

[Krunok]

Squarewaves useful?, Maybe, depends

LOOL

 

[solderdude]

Maybe squarewaves is something for Ian Dury and the Blockheads ?

 

[restorer-john]

Yes. This is why I take issue with those DAC single sample impulse filter tests. OK, they have use in showing what type of filter it is, but beyond that it has no relevance. A single sample is an illegal signal and will never be encountered as the ADC should filter anything above 1/2 FS. So you want to see what an output filter really does, put in a half sine cycle at 22.05kHz (for 44.1kHz)

Can be used for a fast and visual confirmation of absolute polarity through a digital system.

 

[restorer-john]

Don't you want to know how much garbage there is above 20kHz which may hurt the sound when 'folded back' into the audible range ?

For poorly designed D/A converters, I absolutely want to know what unrelated HF rubbish there is. I'm used to digital gear where there is nothing above 1/2 FS. The proliferation of DS D/As and non-existant filtering has created some pretty bad (cheap) implementations in the consumer space IMO.

As for square wave testing, I use it all the time for amplifier testing, but my generator is an old analogue one- it has none of the pre/post ringing of a DDS generator. You can't draw any meaningful conclusions from putting a bandwidth limited, heavily ringing signal into a transducer and then commenting on the waveshape- something I've seen done by headphone 'testers'.

 

[solderdude]

Yes, indeed.

There was a case where a certain prototype headphone was shipped to various reviewers and measurement folks for evaluation.
I was the only one that noticed the phase was 180 degrees wrong.
This was noticeable because of the impulse plot pointing downwards and reported it.
The manufacturer was glad I caught it...

 

[maverickronin]

I really need to find a way to listen to the HD800. Can you elaborate on these aspects a bit, in particular those that you find to be independent of frequency response?

The differences lie mostly in the 'soundstage width'.
The HD650 is more 'narrow' and while no slouch cannot match the 'ease' one can pinpoint instruments with.
The HD800 is almost effortless where the HD650 still requires some 'straining'.

The soundstage you can get with normal stereo mixes is what really sets the HD800 apart and it's mostly due to the position of the drivers. They're angled and set set much farther away from the ear than in most headphones. This changes the interaction with your outer ear and adds more of your personal pinna transfer function to the final sound which makes things sound further away than usual for headphones.

This isn't more common is because it also creates other problems which can be difficult to deal with. The HD800's 6KHz peak and resonance issues are symptoms of this which aren't completely delt with stock, even on the HD800S.

 

[maverickronin]

I was the only one that noticed the phase was 180 degrees wrong.

Whenever I go to a show or a meet I always find at least one thing with left and right channels reversed

 

[derp1n]

Stock, I find the HD650 'better' as the HD800 is too 'thin' and 'overly detailed/sharp'. The HD800S is 'slightly less 'extreme' but still too much for me. Both need EQ to me.

What EQ are you using for both? I wonder if the 5 band on the ADI-2 DAC is sufficient to try this out.