[Edric Li]

Remember the Harman Curve isn't a "flat" curve.

So what is your definition of flat? I wasn't asking for your personal preference target, but your personal flat target. Do you perceive a Harman-curve headphone as flat, or more bass than flat? I am using the word flat as in the kind of sound that, when you hear it, you say "I may or may not like it, but this is flat to me." I understand that you have different definition about flat for headphone and speakers; they sound vastly different, after all. I am asking about your flat definition for headphones.

I think my reasoning is valid if we agree on the premises:
- That there is a subjectively flat sound by headphones in your opinion. Not a agreed-upon flat target, but *your* flat target.
- That the Harman IEM/HP target curve increases the bass of, and is otherwise similar to, your subjectively flat target.

Is this too much to ask for?

Are we on the same page now?

 

[bigshot]

My sub is designed by Bob Carver. It's a very strange design... it is extremely small and has incredibly low bass extension at loud volumes, but it is massively inefficient. The on board amp is 2,700 watts! I played it for one of the lead guys from Dolby and he was astounded at how it filled the room. (Unfortunately, the day before he arrived, my cleaning lady had bumped the settings in the back and it was about 5dB too loud.)

The thing about Bose was that they advertised themselves on sound, but the real selling point was usually the way it looked. They used all kinds of tricks to make the form of their equipment look like modern art. They were "wife approved" but they weren't the best choice for sound.

 

[bigshot]

So what is your definition of flat? I wasn't asking for your personal preference target, but your personal flat target. Do you perceive a Harman-curve headphone as flat, or more bass than flat? I am using the word flat as in the kind of sound that, when you hear it, you say "this is flat to me."

Truly flat for everyone only exists with speakers. If you measure at the ideal listening position in a room and run pink noise tests, you can precisely calibrate for a flat response. But the room has as much to do with whether something is flat or colored as the transducers. That's why you run tones and EQ to a balanced response. Balanced is balanced for everyone because it is the same kind of sound that we hear everyday in real life. But balanced is different for every room. You can take speakers that measure perfectly flat in an anechoic chamber and drop them into a living room and they are WAY off. You have to calibrate for the room.

But if you are putting an ear cup right over your ear and shooting the sound directly down your ear canal, all bets are off. There is nothing real about that. There's no room to calibrate the EQ to be flat for. How it sounds depends mostly on the shape of your outer ear, the shape of your ear canal, the position of the transducer over your ears, and the way the seal around your ears affects the response. One person's "balanced" may be quite different than another person's. That's why the Harman Curve is an averaged curve for a large sample group of listeners. It isn't an objective calibration. It is a general starting place.

Headphones are imprecise when it comes to response. That's why there are so many headphones with so many different sound signatures. You have to find the ones that suit your particular ears and ear canals. There is no one size fits all objective "flat".

 

[Davesrose]

My sub is designed by Bob Carver. It's a very strange design... it is extremely small and has incredibly low bass extension at loud volumes, but it is massively inefficient. The on board amp is 2,700 watts! I played it for one of the lead guys from Dolby and he was astounded at how it filled the room. (Unfortunately, the day before he arrived, my cleaning lady had bumped the settings in the back and it was about 5dB too loud.)

The thing about Bose was that they advertised themselves on sound, but the real selling point was usually the way it looked. They used all kinds of tricks to make the form of their equipment look like modern art. They were "wife approved" but they weren't the best choice for sound.

Haha....well the 901 wasn't approved by my mom. The story is that my dad was still a medical resident. They had saved 2K for a good dining room table. My mom sent my dad out to get a nice dinning room table, and he came back with the 901s. For her, my mom has always just seen them as a planter. My dad was sold on the omnidirectional aspect (and if you read the Stereophile articles from the time, that was their selling point).

When I was a kid, my dad first gave me a small speaker system he had...then it died and we went to Circuit City to demo different bookshelf speakers and amp. Was it a 201 or 301 bookshelf I demoed....it didn't sound as good as what we wound up with: a DCM coaxial speaker and Harman Kardon stereo amp. I think Bose is good with their noise canceling headphones, but when it comes to speakers....they've always been lacking (for what I look for: at least full range dynamics). I was also a die hard Harman Kardon receiver fan ....I upgraded until 7.1 HDMI lossless surround audio. Now HK has dropped receivers and just divisions of sound bars it seems. So my 3D audio surround is a Denon receiver (it also has Auro-3D....which it and IMAX Enhanced seem really niche).

 

[bigshot]

There are so many great choices for receivers now. Dennons are fantastic. I have a Yamaha, the reason I chose it was the DSPs. Yamaha sent engineers all over the world to measure everything from the Roxy on the Sunset strip to the Musikverein in Vienna. They incorporated that data into their multichannel ambiences. Dennon has some great ones too. It's really a golden age for home audio electronics. It's hard to go wrong.

I have theories on speaker dispersion. I think wide dispersion is vital for the rear channels where you want an even flat plane spanning the whole rear wall. I use KEF speakers with a radial design that have a super wide dispersion for the rear. But for the mains and most especially the center channel where vocals are usually placed, a more directional sound is important. I have two sets of mains. On the outsides are my 70s studio monitors with very directional treble to create good stereo separation. Inbetween the outer mains and the center is a set of JBL towers with wide dispersion. I use these because my theater is 20 feet wide and bridging that gap to the center needs a little help. The center channel is a horn loaded Klipsch that is more directional. This helps focus vocals in the center. Then the Sunfire True Sub I already mentioned. This combination breaks a lot of rules, but I have more than one seating position in my theater, and this averages out better than focusing just on the primary position.

 

[Edric Li]

Headphones are imprecise when it comes to response. That's why there are so many headphones with so many different sound signatures. You have to find the ones that suit your particular ears and ear canals. There is no one size fits all objective "flat".

But I am just asking for your subj.... never mind, I give up.

 

[bigshot]

My subjective opinion? For me the Oppo PM-1s come as close to my own ideal curve as any I've heard. They hew pretty close to Harman because I want as close to a balanced speaker-like sound as possible. The problem with headphone response charts is that a lot of people doing measurements apply a correction curve to them, making a direct comparison with the Harman curve difficult. That is why response charts look different from one person doing measurements to another too. Headphones are difficult to pin down. You kind of have to just try them and see especially if the nooks and crannies in your noggin are unique. I guess the holes in my head are pretty ordinary. Harman works for me.

But when it comes to speakers, there actually is an objective flat.

 

[Davesrose]

There are so many great choices for receivers now. Dennons are fantastic. I have a Yamaha, the reason I chose it was the DSPs. Yamaha sent engineers all over the world to measure everything from the Roxy on the Sunset strip to the Musikverein in Vienna. They incorporated that into their multichannel ambiences. Dennon has some great ones too. It's really a golden age for home audio electronics. It's hard to go wrong.

Curious, does your Yamaha have Auro then (mention of Europe)? So with Denon, the higher end ones have Auro (a surround format from a European company that only has a few native tracks in Europe). I do like the fact that my receiver has Auro: I do try it from track to track. I find it can sometimes be better than Dolby Surround or DTS:Neural when it comes to regular stereo or a given 5.1 scheme. I also like fine tuning....so I've calibrated my receiver based on SPL measurements and laser measurements.

 

[bigshot]

Yamaha has a proprietary up mixer that is the best thing since sliced bread. I use it with almost everything from old mono movies to audiophile stereo recordings. I've tried to figure out what it does. It seems to throw the phantom center to the center channel with high degree of accuracy. In the rears, it uses the distance measurements to open up the sound and make it fill the room. If you listen to regular stereo playback, and then cup your hands right being your ears, you can hear sort of what it sounds like. Finding out how these things work is very difficult. Each manufacturer is secretive about how they do it. But the Yamaha up mixer is a lot better than Dolby and DTS's equivalents. The Yamaha doesn't have Auro. I think that came out after I bought this receiver.

 

[castleofargh]

So what is your definition of flat? I wasn't asking for your personal preference target, but your personal flat target. Do you perceive a Harman-curve headphone as flat, or more bass than flat? I am using the word flat as in the kind of sound that, when you hear it, you say "I may or may not like it, but this is flat to me." I understand that you have different definition about flat for headphone and speakers; they sound vastly different, after all. I am asking about your flat definition for headphones.


Are we on the same page now?

He’s right to point out that Harman target is not flat. They clearly tested for preferred FR. It could be argued that at large, perceived flat or a slight tilt toward warmth tend to be preferred by most, but Olive&co did not say anything about seeking neutral.

Back to bass, ambient sounds have tactile bass impact that strongly increases and changes how we perceive the low end. It's been hypothesized by many that the desire for more bass on headphones and IEMs, might be our way to compensate for the missing tactile feeling. Is it the reason? IDK. But the trend of wanting more bass than on speakers or acoustic events is long going. As it is only a substitute, it makes sense to me that different people might interpret it differently. Some could feel like they are getting back some of those visceral sub feelings, while maybe all you feel is too much low end disturbing the tonal balance? I only experienced me, so I couldn't say how most other listeners feel.

Personally, I have another issue where the measurement tool might give me similar low end when I very clearly feel them as different(even after applying a solid low pass to remove differences in the upper range. After matching the SPL output and after doing my very best to find tips that would seal my ear canal).
This is an example of what troubled me with bass measurements(first paragraph after the graphs):
https://www.head-fi.org/threads/hea...setups-different-results.751100/post-13933374
And this is all done by me so I could control the measurements and make adjustments at will. And repeat such measurements as many times as I wanted ever since. It's just an example with IEMs, but I felt the same way with various headphones, where similar low end(isolated) felt clearly more ”tactile” on certain headphones. IDK why. Maybe distortions, maybe the amount of skin receiving the wave. I also considered that some headphones might get shaken more than others, or at least transmit more of the vibrations through the pads, giving us some actual tactile bass, albeit only localy.
It's a trend for me those days, but I don't have an answer.
I just know that at large, people seem to enjoy a little bass boost on headphones, and that as you pointed out, they might like to have more boost on IEMs. That seems to be preferred for reasons. Will it feel neutral? IDK. Probably not.

 

[71 dB]

My sub is designed by Bob Carver. It's a very strange design... it is extremely small and has incredibly low bass extension at loud volumes, but it is massively inefficient. The on board amp is 2,700 watts! I played it for one of the lead guys from Dolby and he was astounded at how it filled the room. (Unfortunately, the day before he arrived, my cleaning lady had bumped the settings in the back and it was about 5dB too loud.)

The thing about Bose was that they advertised themselves on sound, but the real selling point was usually the way it looked. They used all kinds of tricks to make the form of their equipment look like modern art. They were "wife approved" but they weren't the best choice for sound.

Sunfire? I have measured it for a Hi-fi Magazine many many years ago. Wicked sub! Subwoofers need a lot of air volume OR power in order to produce a lot of sound. This little cube needs all those watts to make its long stroke drivers move. In fact we were nervous about blowing the fuse in the acoustics lab when we measured it.

Yes, Bose is about design and branding. It is less about sound in a "bang for the buck" sense.

 

[bigshot]

Yes, Sunfire True Sub. The excursion on it is scary. I try not to think about it!

 

[ADUHF]

I'm enjoyin all the hi-fi talk.

To go back to some of the OP's original questions though... In case it wasn't apparent from some of my previous posts, I do also think that a neutral response should include some type of a bass boost. Because I subscribe to the "room sound" theory. When you put speakers that measure flat in an echo-free chamber into a room with some reflectivity, they acquire a darker tilt. Because they do not (usually) have the same amount of dispersion or directivity at all frequencies. This is what Floyd Toole talks about in the video I posted earlier.

The shelving question is a bit harder to answer. Speakers are imperfect instruments though. And eventually start to falloff at some point in the lower frequencies. And if you are using that as your model for the sound of a headphone, then it may make some sense to either level or roll off the sub-bass. At least a bit, to better approximate that. Exactly where and how much is sort of up for grabs though.

It would not be that hard for the manufacturers of the head and torso rigs which are used to measure headphones to include a compensation curve for room effects like this. They could very easily set up a pair of flat speakers in an average sized room, with average reflectance. And measure what the in-ear response is on their rig from a typical listening position. Or averaged over several positions.

Doing the measurements for a free field and diffuse field are actually alot harder, because those require either an echo-free chamber. Or a totally reflective room. Neither of which is especially easy to create. A room that replicates the average size and reflectance of a typical listening space in a home would probably be a trivial task to setup by comparison. So I don't know why it has not been done before.

If they wanted to, they could even do this for a variety of different spaces, and speaker configurations. So you could take your pick and choose the one you like the best. That sort of information would probably also add some add'l value to their products.

 

[ADUHF]

I also don't know everything about this subject. But I think you should be carefull not to confuse frequency response with the actual frequency spectrum of the content that is being played, or with the maximum sound pressure level curve of the playback system. Movie sound tracks can contain very strong low frequency effects. If you play that over a "flat" system you will get those same strong low frequency effects just like intended, and at the intended levels if your system can handle the SPLs required - per frequency band - for it. Also keep in mind that there is only one LFE channel (or maybe a few in pro cinema, that I don't know but still not as many as the other channels, also note that I am not talking about the number of subwoofers: that can be larger than the number of LFE channels) that has to keep up with the total SPL of all other channels together.
Here we also get to the reason why the LFE channel is attenuated on the medium. If all channels would be put on the medium suitable for equal gain at playback, then the LFE channel would hit the maximum signal level far earlier than the other channels. That would mean that a large part of the level range of the other channels would be wasted. The other channels probably would never go higher than -10 dB. If you attenuate the LFE channel 10 dB relative to the other channels, then you can push the other channels close to 0 dB as well.

I appreciate the additional info and insights on this, sander99.

It is my understanding though that the reference listening level standards described in that THX article are designed to accurately replicate the conditions in which the movie's soundtrack was mastered. So the medium shouldn't really have any effect on the final result that you hear in that regard. So I guess I'm having a little trouble seeing what the relevance is on that.

The THX article addresses the issue of cross-over as well. And suggests an additional 6 or 8 dB of volume (on top of the +10 dB) on the sub-woofer to compensate for that. So either way you look it, I think you're probably still getting something roughly on the order of an extra 10 dB in the sub-bass frequencies at the listening position, whether it's handling the bass for the other speakers or not. No?

I'm probably being a little deliberately dense here, btw. Because I'd like to see if someone can actually explain a little better why my rather simplistic way of looking at this could be flawed.

If the cross-overs are disabled on the other channels though, then they should also be able to contribute to the lower frequencies. So there shouldn't really be any need for the sub-woofer to have to "keep up" with what they are doing in the higher frequencies, if multiple channels are active. And it would seem as though the sub would act primarily as a low-frequency amplifier.

If only two channels are active, the sub and another channel, then you still have the potential for a 10 dB (or greater) increase in the sub-bass frequencies, whether the cross-overs are enabled, or not. Because both speakers can potentially contribute in that range if the cross-overs are disabled. And if you get a bigger or 2nd sub to cover the cross-over information (like the article suggests), then the sub(s) should still have the add'l 10 dB on top of what it needs with the cross-over active. No?

All of the above should apply to both the mastering and listening spaces. Because they are designed to work in parity... And there are obviously some folks here with some experience in setting up multi-channel systems. So I'm hoping maybe one of them can explain to me how this is wrong.

 

[71 dB]

Oh, no wonder I have been so lost in this tread. Harman Target Curve is a thing apparently and it simulates how loudspeakers sound in a room. I need to study this subject before I can understand the content of this thread properly I think. I assumed this was simply about "bassy" and "neutral" sound. Sorry about my ignorance.