- Dec 15, 2019
Well I guess, there's no beating around the bush on the conclusions of that review.
They are not posting raw measurements for that. They are post processing it to their thinking.Rtings also rates them well for distortion:
Since finding the Audiosciencereview website I can’t bare to read purely subjective reviews. Time after time “go to” products and manufacturers are shot down in flames by real measurements. All the hyperbole and 5-star ratings are just a complete waste of time.
Thank you for the work you do.
While the DT 990 Pro is a comfortable headphone to wear, ...
... It is just too broken.
Your own site shows that the dt 880 600 ohm ( lower than senn 650) has at least ok distortion ( the dt 990 pro has no distortion measurement) ... its looks and sounds way more positive than you sound over here....
The 600 Ohm version? I inherited the 250 Ohm version some 5 years ago and have no clue how old they are. Is there a way to find out whether they have those zeners, and how to get rid of them?
Very nice review re going through the dialing in of the EQ process and then particularly your measuring of the headphone after EQ, and amoungst that the revelation that boosting the bass actually didn't even result in a bass boost at all, that was quite a revelation, and to me a testimony of the problems with this headphone! It's unfortunate, it's a little sad when a headphone can't be saved by EQ.This is a review and detailed measurements of the Beyerdynamic DT990 (250 ohm) open back headphone. A member was kind enough to purchase one new and drop ship it to me due to request from membership! The DT990 costs about $160 and has been around for many years.
I like the look of the DT 990:
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The pads felt hard at first but after just a couple of hours of use, they became more comfortable. Combined with light weight of the unit, they are nice to wear.
I did not care as much for the plastic cups, nor the sharp edges of meta pieces:
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The cups are round and large making for easy fit not only around your ears but also the measurement gear. I have never had a headphone so easy to mount on my fixture to measure.
Note: The measurements you are about to see are preformed using standardized GRAS 45CA headphone measurement fixture. Headphone measurements require more interpretation than speaker tests and have more of a requirement for subjective testing as a result. In addition, comparison of measurements between different people performing it using different configurations requires fair bit of skill. So don't look for matching results. Focus on high level picture. Listening tests are performed using RME ADI-2 DAC and its headphone output.
Beyerdynamic DT 990 Pro Measurements
Let's start with frequency response of DT 990 and comparison to our preference target:
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We have some serious issues here. The headphone is tuned to produce its max bass output at around 150 Hz below which it drops rapidly. Inverse is in play above 2 kHz where we way overshoot. Predicted response then would be a bit boomy and very sharp and bright. Here is the same as relative measure:
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Bad news doesn't stop there. Distortion is quite high:
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The DT990 is also extremely insensitive:
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You better have a very high performance headphone amplifier that can drive its high impedance and provide the required power:
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Notice how 250 ohm is the minimum impedance. Close to tuning frequency of the headphone, it shoots up to 350 ohm so your headphone amp needs to also have a very low output impedance as to not impact the frequency response of this headphone. Heaven knows you don't want to mess up the response of this headphone any more than it already is!
Group delay response shows some areas you don't want to eq as usual (shown as dip in frequency response) and some fuzziness that I rather not see:
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Beyerdynamic DT 990 Pro Headphone Listening Tests and EQ
It took all of a few seconds to want to rip the DT 990 off my head as I always start with female vocals and this headphone shred the vocals to pieces. And proceeded to drill into your head with those shards! This thing is so bright that it brought high frequencies resonances that I did not even think were in the music! This stood out even more because there is little sub-bass energy. The peaking around 150 Hz provides a bit of help there but also can sound a bit boomy on some content.
Distortion was a serious problem. At moderately high level it would add this warbling sound to many tones from vocals and some lower notes. At higher levels bass notes would start to create ticking sounds. You wouldn't normally listen that this level though so it is an engineering failure more than audible one (without EQ).
I am always hopeful that I can fix headphones with EQ but my first two tries last night were met with failure. This headphone's main saving grace is its rather good spatial qualities. Alas, fixing the high frequency peaks and levels by eye killed that aspect and still left the nastiness that was in there at times. Any attempt to boost the bass frequencies resulted in nasty bass distortion and worse warbling sound per above.
Right when I was going to give up, I decided to use an assisted method to develop the EQ. I swept the headphone and manually dialed in EQ settings and iterated to get rid of the peaking in three high frequency bands. This was the result:
View attachment 109727
Focusing on the left, I had dialed in some 6 dB yet the effect was minimal in response. I pushed that up to eve 10 dB and the graph simply did not change indicating the driver is out of gas. Audible effect of that bass boost was horrible with distortion galore. So I took that out. I then found the sound to be rather dull and spatial effects compromised. So I dialed in a shelving filter that boosted the entire range. This was the final result:
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You can mess with that shelfing filter (Band 5) to your taste. On some content I wanted it higher, on some others, less. The latter is what I am showing here.
I must say, I was surprised how this finally salvaged the headphone sound. I am listening to it as I type this and it almost sounds "normal" in a good way! Mind you, if you turn up the level too much, the warbling sound comes to haunt you but that is likely not your everyday level.
While the DT 990 Pro is a comfortable headphone to wear, it has a seriously flawed design with poor frequency response which exaggerates the heck out of highs and dumps a bunch of distortion in there for good measure. It also lacks deep bass reproduction. Careful equalization did manage to salvage it at the end but took a lot of doing.
I am not going to recommend the Beyerdynamic DT990 Pro. It is just too broken. Even though EQ helped a lot, it is still an inefficient headphone with high distortion. If you have one, use my EQ and comment on how you like it. Otherwise it is a pass with or without EQ. Let's hope we can find a headphone as comfortable as this but with much better engineering.
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
I like em too, with and without eqI like the DT990 Pro-250 after some EQ (differs from Oratory and Amir) and generally listen at levels I can handle for several hours so I never run into distortion that high. I just don't play very loud. Well sometimes when I like a song or want to know its limits.
DT990 distortion (around 90dB SPL on average) and is similar to what Amir measured.
Also included CSD, FR and Group delay (the 50Hz wiggles should be ignored)
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The DT990 are workhorses. Easy to replace parts, incredibly sturdy, comfortable (for most).
I only EQ away the 150Hz hump and the broad treble peak.
Like Amir I don't EQ the subbass. I find it is not needed.
Was about 35 years ago I purchased that one (600 Ohm)
You can just cut away the diodes (is what I did)
The 35yo DT990-600 measures differently as the DT990pro250
Yes, worth noting also non-audio aspects. I wish EU regulations would be more strict and smash all those "fancy disposable" headphones out of EU market at least, we hear support for sustainability everywhere but the market is flooded with "junkyard fillers".The DT990 are workhorses. Easy to replace parts, incredibly sturdy, comfortable (for most).
I uh, geez... I feel kind of bad for laughing at this guy.
Looks like the way to listen to these DT990 is with old earpads, tames the treble peaks, which also makes them easier to EQ:Oratory1990 has measured the DT1990 and the T1.2.
View attachment 109731
Source: https://www.dropbox.com/s/o7zkgbc1b6flevp/Beyerdynamic DT1990 (A Earpads).pdf?dl=0
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Source: https://www.dropbox.com/s/ipqx4n8hpeg952b/Beyerdynamic T1 2nd.pdf?dl=0
Also, here is his measurement of the DT990 for reference.
View attachment 109733
Source: https://www.dropbox.com/s/gryfjs3i30c7r5h/Beyerdynamic DT990 (new earpads).pdf?dl=0
Also, since it was mentioned by @sacguy231, here is his measurement of the Amiron Home.
View attachment 109734
Source: https://www.dropbox.com/s/fjmrgdg3dvi0cqf/Beyerdynamic Amiron Home.pdf?dl=0
Yes, that is interesting, I had too noticed that Oratory does the Low Shelf Boost of the bass on this headphone. I'm assuming that @amirm was adding a Low Shelf Boost when listening & measuring at the 94dB level (is that peak or average) when he found that the bass didn't actually increase (limits of the headphone). We'd have to know more from Amir re what the listening level was during this observation to get another data point to your experience, but I'd be kinda surprised that Oratory would put in a Low Shelf Bass boost if it was having no effect....yeah we need more clarity on the listening levels. Either way it's not good from an engineering standpoint though, because all headphones tested here so far were able to actually apply some kind of bass boost IIRC.I'm not sure what possessed me to buy these. Uncorrected, they sound bad to me just like Amir described. Somehow they sounded good to me when I demo'd them at the store.
Using Oratory1990's PEQ corrections, though? Absolutely love them.
Interestingly, Oratory's corrections don't look too much like Amir's.
So my listening experience is objectively quite a bit different than Amir is reporting. Oratory takes a few more dB out of that midbass hump, and boosts the deep bass significantly. Those were the most glaring problems to me. @amirm -- I'm curious about your reasoning there. You're showing a 5dB surplus at ~150hz relative to the target curve but you only take 2dB out via EQ. Thoughts?
edit: Thanks to the comparison posted below, I see the net result of Amir vs. Oratory1990's corrections are roughly the same in that 150hz region.
You also don't boost the deep bass at all, but I assume that's because you were running out of headroom and having excursion issues? I think you like to listen to headphones a *lot* louder than I do. I have to crank these way past my comfort zone to get these headphones to pull those kinds of shenanigans.