What Headphones do not need (or scream for) EQ?

[oleg87]

Between perceptual/human differences, manufacturing tolerances, and the difficulty of disentangling all of these factors, I'm pretty skeptical that such headphones exist even if we aim for an objective target response. Oratory1990 has Harman-targeting EQ presets for most of the various headphones I've owned, and for me it's a total tossup whether I find his EQ adjustment an improvement or unlistenable, even though they are derived by a professional, on professional test equipment with presumably consistent measurement methodology. They are certainly not being made to sound like each other, to my ears.

 

[spartaman64]

off of the top of my head. ksc75, akg k371, hd6x0, hd560, he400se, sundara, elex, edition x, clear, utopia, susvara, he1

 

[ADU]

Between perceptual/human differences, manufacturing tolerances, and the difficulty of disentangling all of these factors, I'm pretty skeptical that such headphones exist even if we aim for an objective target response.

I am less skeptical about this being achieved. But have not found a pair yet that really ticks off all of the boxes at a price I can really afford. Which is why I haven't really given any specific recommendations.

The Sennheiser HD6XX seems to have some positive qualities, for an open headphone. It looks like it could be a little too mid-forward. But appears to be better extended in the bass (for an open-back, that is) than both the HD600 and HD650. And not as dark in spots in the treble as the HD650. Both of these things look like positive developments, in terms of tuning. I have no idea how it performs though in terms of imaging, clarity, comfort, etc. though.

The HD560 looks even better extended in the bass than the above. And supposedly has better drivers and soundstage than the others. The tuning in the treble and upper mids looks more uneven than the 6XX though. And when I tried a pair on in a store, I wasn't overly impressed by their fit and comfort. (I have not tried on the 6XX yet for comparison though.)

I have also tried or used many of the more popular low cost "studio" HPs, like the AKG K361, K371 and K553, AudioTechnica M30x, M40x and M50x, Sennheiser HD 280 and 380 Pros, Sony MDR-7506, Beyerdynamic DT-770, and so on. And can't really give an unqualified thumbs up to any of those, for various reasons. Though some of them have positive qualities, and can probably sound quite good with the right music, and amp (and ears).

I would love to see some new players in the studio headphone market though, because many of the above are beginning to feel rather stale at this point. So I'm also looking at new offerings from companies like Austrian Audio, Neumann, Rone, and so forth. And I'm interested in some of the lower cost planars from HiFiMan. I wish Kali would try some headphones too, because they are doin some interesting studio monitors. And seem to have some pretty good designers.

Denon also looks like it makes some nice dynamic driver closed-backs, but they are a bit pricier. And tuning might not be perfect. There are others who could certainly also be players in this market though with the right products, such as Shure, Philips, PSB/NAD...

Over-ears are generally the only thing that interests me. The Audezes, Focals, DCAs, and the like are all beyond my means though. So I don't spend much time thinking about those.

 

[solderdude]

The Sennheiser 6XX seems to have some positive qualities, for an open headphone. It looks like it could be a little too mid-forward. But appears to be better extended in the bass (for an open-back, that is) than both the HD600 and HD650. And not as dark in spots in the treble as the HD650. Both of these things look like positive developments, in terms of tuning.

Consider the HD6XX is using the newer pads. HD650 with fresh original pads vs the new pads.

And then there were production spread/changes.
Below are 2 averages over a number of HD650 (Sonarworks measurements) which show not all HD650's were created equal for a while around end 2018.

NOTE: this is not about black vs. silver/white drivers and before Sennheiser switched from pad manufacturer.

Early black (with fresh HD650 pads) vs silver/white screen HD650(2017) and a 'veiled' HD650 from around 2014. (note the dB scale it differs to make differences more visible)
All measured on the same fixture.

 

[ADU]

^ Interesting. have you measured any HD6XXs, solderdude? And do you feel that this negates some of its positive qualities by comparison?

 

[solderdude]

I haven't.
I have it from a good authority, however that HD650 and HD6XX are the same headphones.
They have a cheaper paint job (single color dark blue) have a cheaper cable, cheaper box, cheaper pads, do not have the 6.3mm to 3.5mm cable and are produced in one large continuous batch and required only 1 separate shipping to 1 distributor that has less markup/margin than importers + dealers.
Making one large continuous batch has the advantage (lower price) as the same production line(s) does not have to be 'converted' for making other models for an extended time period. This saves money. Shipping a large batch to 1 distributor it much cheaper than shipping multiple smaller batches (on demand) to various importers globally.
This is how the HD650 can be had for a lower price and is called the HD6XX.
I was told the drivers are still matched in the HD6XX so there was no skimping on the price there. This is because for production of the HD6XX the same steps are taken (same production line and sourced materials)

The reasons HD6XX is having different measurements/sound from 'HD650' is because in those cases the 'HD650' it is compared to is not from the same production year/batch and often also the early vs recent pads. Not all HD650 are exactly the same.
When someone were to compare HD650 and HD6XX from the same production year the found differences will fall within production tolerances.
There are differences in FR between HD650 (not between L and R that much) over the years anyway due to production tolerances and building material tolerances.

Also current HD600/650 all ship with cheaper boxes, are assembled in a lower wage country and have cheaper pads now which is a way for Sennheiser to be able to keep it at the same MSRP.

 

[TomW]

Also current HD600/650 all ship with cheaper boxes, are assembled in a lower wage country and have cheaper pads now which is a way for Sennheiser to be able to keep it at the same MSRP.

I'm puzzled by your comment as the boxes and Senns website states these are made in Ireland?

HD650 prices went up quite a bit this year from 349€ to 379€ real price. Sennheiser does control street price quite well and MSRP doesn't mean a lot.
Drop also raised their prices for the HD6xx a bit.

 

[solderdude]

In 2019 this was the plan:

The Brașov factory will also be responsible for products including the HD 600 headphone series for the audiophile market, as well as professional products including the HD 300 Pro studio monitoring headphones and the new XS Wireless Digital – a wireless microphone series for musicians and videographers.

The Romanian plant started out with HD25 and know the HD58X assembly also went to Romania. Drivers are still manufactured in Ireland. (AFAIK).
I think pricing of all products went up in 2022.

 

[Dunring]

I'm puzzled by your comment as the boxes and Senns website states these are made in Ireland?

HD650 prices went up quite a bit this year from 349€ to 379€ real price. Sennheiser does control street price quite well and MSRP doesn't mean a lot.
Drop also raised their prices for the HD6xx a bit.

I just got one used but like new from a distributor on eBay and yep the boxes are really flimsy and pads don't seem the same, it said made in Romania but designed in Germany too. Drop always raises their prices ahead of the holidays then drop the bomb on black Friday on many things including the HD6xx (at least they have the last few years). This is the box they came in, not the big 15" long one with the foam.

 

[Robbo99999]

I'll say that out of my own collection of headphones that I can get away without EQ on the Sennheiser HD600 and also on my Sennheiser HD560s, but the HD600 is closest to it's best potential at stock vs the HD560s. EQ helps the HD600 just a little, but it helps the HD560s a lot - to an extent that for me the HD560s is a better headphone than the HD600 when both are EQ'd. All my other headphones aren't really much good at stock (AKG K702, NAD HP50, Hifiman HE4XX). Ah, for IEM's, the Truthear Crinacle X Zero (recently reviewed on ASR) is really quite good at stock (almost perfect) and doesn't really need EQ, although EQ does take away a little of the harshness for longer listening sessions.

 

[TomW]

In 2019 this was the plan:

The Brașov factory will also be responsible for products including the HD 600 headphone series for the audiophile market, as well as professional products including the HD 300 Pro studio monitoring headphones and the new XS Wireless Digital – a wireless microphone series for musicians and videographers.

The Romanian plant started out with HD25 and know the HD58X assembly also went to Romania. Drivers are still manufactured in Ireland. (AFAIK).
I think pricing of all products went up in 2022.

As far as I know the Romanian factory belongs to the pro-audio division of Sennheiser (the original Sennheiser) and the consumer Sennheiser (which was bought by Sonova) produces in Ireland. So the manufacturing of the HD6xy series went from Romania back to Ireland.

I have a brand new HD660s which shows "made in Ireland" on the box.

Quote from the Sennheiser website:
Made in Ireland at a state-of-the-art production facility, the HD 650 delivers more: more details discovered, more musicality, and definitely more time for blissful listening.

So I assume they are from Ireland these days.

I also own a Romanian made HD650, bought 2020 or so.

 

[ADU]

I haven't.
I have it from a good authority, however that HD650 and HD6XX are the same headphones.
They have a cheaper paint job (single color dark blue) have a cheaper cable, cheaper box, cheaper pads, do not have the 6.3mm to 3.5mm cable and are produced in one large continuous batch and required only 1 separate shipping to 1 distributor that has less markup/margin than importers + dealers.
Making one large continuous batch has the advantage (lower price) as the same production line(s) does not have to be 'converted' for making other models for an extended time period. This saves money. Shipping a large batch to 1 distributor it much cheaper than shipping multiple smaller batches (on demand) to various importers globally.
This is how the HD650 can be had for a lower price and is called the HD6XX.
I was told the drivers are still matched in the HD6XX so there was no skimping on the price there. This is because for production of the HD6XX the same steps are taken (same production line and sourced materials)

The reasons HD6XX is having different measurements/sound from 'HD650' is because in those cases the 'HD650' it is compared to is not from the same production year/batch and often also the early vs recent pads. Not all HD650 are exactly the same.
When someone were to compare HD650 and HD6XX from the same production year the found differences will fall within production tolerances.
There are differences in FR between HD650 (not between L and R that much) over the years anyway due to production tolerances and building material tolerances.

Also current HD600/650 all ship with cheaper boxes, are assembled in a lower wage country and have cheaper pads now which is a way for Sennheiser to be able to keep it at the same MSRP.

Thank you for the reply on this, solderdude.

I haven't listened to either headphone (which is an important caveat here), at least not recently. But many of your comments above seem to be favoring the 6XX over the 650! In terms of price, consistency, and so forth. Am I reading this wrong?

I'll say that out of my own collection of headphones that I can get away without EQ on the Sennheiser HD600 and also on my Sennheiser HD560s, but the HD600 is closest to it's best potential at stock vs the HD560s. EQ helps the HD600 just a little, but it helps the HD560s a lot - to an extent that for me the HD560s is a better headphone than the HD600 when both are EQ'd.

Interesting. The HD600 does not seem to have a great rep for its soundstage (if you believe in stuff like that).

 

[solderdude]

But many of your comments above seem to be favoring the 6XX over the 650! In terms of price, consistency, and so forth. Am I reading this wrong?

If one is looking for a HD650 but for a lower price and does not mind the dark blue color of the HD6XX then one has 2 options.
Buy HD650 second hand (and a set of new pads and maybe a new headrest) or buy the HD6XX.
Price/performance ratio for a new headphone, of course, goes to the HD6XX.
Personally I prefer the HD560S (with filter) and HD800 (with EQ) over the (EQ'ed) HD650 but that's just me.
I shave off some warmth and add a bit of sub-bass for the HD650 which improves it but not the 'imaging' alas.
I still keep the HD650 handy as it serves as a great reference when doing measurements.

 

[Postlan]

The strength of HD600/650 is it only requires gentle EQ below 400Hz. I agree with Bob Kats saying aggressive High Q correction at sensitive area should be avoided, always. EQ certainly fixes a lot of things, but it has side effects.

"personally I recommend you stay away from the HD800. I could never make an EQ that would satisfy. Either it would sound harsh on some material with brass or it would sound muffled after the brass-fix eq. This is because a static equalizer can't really fix a high Q resonance circa 6 kHz. It's a bandaid, not a cure."

 

[ADU]

The strength of HD600/650 is it only requires gentle EQ below 400Hz.

I don't quite agree with this.

I agree with Bob Kats saying aggressive High Q correction at sensitive area should be avoided, always. EQ certainly fixes a lot of things, but it has side effects.

I generally agree with this. And would be particularly careful about using narrow band peak (as opposed to notch) filters.

I know there are some folks who like doing narrow band adjustments by ear, but I haven't personally had too much luck with this with my headphones. And generally try to keep my adjustments a little smoother and broader as a rule. And I would try to avoid headphones with obvious resonances.

Narrow band effects in a headphone's response are not always easy to interpret though. Especially in the treble.

"personally I recommend you stay away from the HD800. I could never make an EQ that would satisfy. Either it would sound harsh on some material with brass or it would sound muffled after the brass-fix eq. This is because a static equalizer can't really fix a high Q resonance circa 6 kHz. It's a bandaid, not a cure."

I won't comment on Bob's approach to equalization per se, because I don't know specifically what it is. If there is a resonance in a headphone though, then the best that an EQ can probably do is simply tone it down by delivering a more attenuated signal at that frequency. The resonance is still technically there though, just as it would be on a regular speaker.

I am generally pretty bullish on most forms of EQ though, for both kinds of transducers. Because I've gotten alot more enjoyment out of my headphones after some basic EQ tweaks than with none at all. And I think the same would probably apply to a loudspeaker.

Some manufacturers are doing some great things with internal DSP and electronic calibration/EQ in their speakers and headphones as well. There are some engineers and audiophiles who frown on this sort of thing though. And given the choice, I personally would also prefer to do all EQ myself.

 

[Postlan]

I don't quite agree with this.



I generally agree with this. And would be particularly careful about using narrow back peak (as opposed to notch) filters.

I know there are some folks who like doing narrow band adjustments by ear, but I haven't personally had too much luck with this with my headphones. And generally try to keep my adjustments a little smoother and broader as a rule. And I would try to avoid headphones with obvious resonances.

Narrrow band effects in a headphone's response are not always easy to interpret though. Especially in the treble.



I won't comment on Bob's approach to equalization per se, because I don't know specifically what it is. If there is a resonance in a headphone though, then the best that an EQ can probably do is simply tone it down by delivering a more attenuated signal at that frequency. The resonance is still technically there though, just as it would be on a regular speaker.

I am generally pretty bullish on most forms of EQ though, for both kinds of transducers. Because I've gotten alot more enjoyment out of my headphones after some basic EQ tweaks than with none at all. And I think the same would probably apply to a loudspeaker.

Some manufacturers are doing some great things with internal DSP and electronic calibration/EQ in their speakers and headphones as well. There are some engineers and audiophiles who frown on this sort of thing though. And given the choice, I personally would also prefer to do all EQ myself.

I guess it depends on what you use the headphones for. For mixing and mastering, aggressive EQ only confuses, as Bob says.

 

[ADU]

I guess it depends on what you use the headphones for. For mixing and mastering, aggressive EQ only confuses, as Bob says.

There are plenty of ways to screw the pooch via EQ.

Most open dynamic headphones are unable to produce decent levels in the sub-bass without noticeable distortion, because of physical design limitations. But this doesn't stop newbies from attempting it. So there's more to it than just high Q filters.

If you're having to make alot of aggressive tweaks of more than 5 or 6 dB one way or another though, to get the type of response you want, then maybe a different pair of headphones or speakers would be worth considering. (?)

 

[ADU]

Slightly OT, but I've posted some new plots comparing the diffuse field compensated response of the Sennheiser HD800S to the sound power response of some neutral loudspeakers, and a -1.25 dB per octave slope in the following topic (on another forum), in case anyone's interested...

Sennheiser HD800S Measurements - Brüel & Kjær 5128

Fig.1 (above): Sennheiser HD800S frequency response, average of four seatings. NOTE: When these measurements were made, the Sennheiser HD800S under test had only been worn by measurement fixtures, so the earpads were in new condition. ]The measurements in this post were made using: Brüel &...

www.head-fi.org

These are also based on measurements made on the new HBK 5128 HATS rig, like the HD650 graphs here.

My general takeaway is that the HD800S is too rolled off in the sub-bass. And depressed in the upper midrange. And maybe a little biased towards some brightness in the treble, especially compared to a linear SP slope. The headphone's frequency response appears to be within +/- a couple dB of neutral across a fairly good portion of the frequency range though. Especially when compared with the average sound power response of some actual loudspeakers that are not tuned precisely to a linear SP response.

YMMV though. And if I were using this headphone, I think I'd probably want to use some EQ to try to address a few of the above issues.

 

[solderdude]

I think no one considers the HD800(S) as a headphone that does not scream for EQ. It does need EQ but just like any other headphone there are people using it as is and like it that way.

Some headphones can be used without an almost obligatory need for EQ but in that case one may have to 'compromise' in one or more aspects a little.

 

[thewas]

Slightly OT, but I've posted some new plots comparing the diffuse field compensated response of the Sennheiser HD800S to the sound power response of some neutral loudspeakers, and a -1.25 dB per octave slope in the following topic (on another forum), in case anyone's interested...

Also OT but I don't think that the sound power response of a loudspeaker should be the reference but the in room response (either predicted or measured) which for good typical cone loudspeakers has a less steep slope, usually around -0.5 dB till -1.0 dB per octave: