[VNandor]

I've been using a HD600 with EQ for enjoying the latest and greatest electronic music for years now. They don't have much sub by default and boosting the sub sounded better to me than boosting the mid bass which they already have too much of for my tastes. I've spent way more time and effort on getting the bass where I wanted for my monitor speakers but with no success. I think they won't ever sound good until I move my setup out the corner of my room.

if I remember correctly (in parT that’s a way of my being lazy with references), our brains have a way of inferring bass an octave lower from harmonic content in the next octave up, so addimg a little in that octave octave up can help us in perceiving bass in the octave below. There’s stuff on the net illustrating this, amd how in some contexts it works (you cam perceive a note for a frequency that was not reproduced at all, for example).

There's a wikipedia article titled "Missing fundamental". The audio processing part says Waves Audio was taking advantage of this effect as early as 1999. But even back then the processing they used was more advanced than just slapping a filter somewhere and calling it a day. I didn't already know any of that, I just know that people nowadays use a more sophisticated approach to increase the perceived sub bass than just using an EQ.

 

[megabigeye]

I recenty tested a NA version using a simple single-BA (legendary ED29689, the same in Etymotic E4R) transducer (14 Ohm at 1 kHz, 105 dB/mW) with different impedance adapters. 150 Ohm is definitely to much.

What do you mean you "tested" it? And you're testing it by using a 14 ohm transducer and a 150 ohm adapter? Wouldn't that be essentially using the 14 ohm transducer with a 150 ohm output impedance?
I'm not trying to needle you or catch you out, I'm genuinely curious because I'm not completely sure how these things work.

I frequently use my North American Lightning dongle with my HD 650 and my DT 1990 and to my ear it sounds fine and gets more than loud enough. Granted, not a scientific test at all.

 

[PhonoPhi]

What do you mean you "tested" it? And you're testing it by using a 14 ohm transducer and a 150 ohm adapter? Wouldn't that be essentially using the 14 ohm transducer with a 150 ohm output impedance?
I'm not trying to needle you or catch you out, I'm genuinely curious because I'm not completely sure how these things work.

I frequently use my North American Lightning dongle with my HD 650 and my DT 1990 and to my ear it sounds fine and gets more than loud enough. Granted, not a scientific test at all.

"Tested" means took the things and tried how they work.

I did add different impedance adapters from 18 to 150 Ohm. For the other tests, I have also made a variable balanced impedance adapter - a lot of interesting observations with different multi-driver IEMs.

A truly perspective-dependent, I either constructed 164-Ohm IEM or used the output impedance of 150 Ohm. The same circuit.

Ethymotic in their E4R started with 100 Ohm impedance (I was told) and are now using 45 Ohm with the same 12-14 Ohm BA transducer.

P. S. Early hit of the "post" button

 

[castleofargh]

A truly perspective-dependent, I either constructed 164-Ohm IEM or used the output impedance of 150 Ohm. The same circuit.

Probably not. Yes for the amp section it's like a load with the sum impedance and it almost always objectively improve the amp's signal. But for the IEM it's an amp with amp+"cable" impedance. Meaning that subjective experience will very much change based at least on the impedance curve of the IEM instead of just being about the amp.
Now you can lower the impact on the IEM side with a voltage divider instead of resistors in series but even then the result is rarely one where the IEM "sees" the exact same impedance and only the amp works better. I guess this could be calculated to come real close but there are limits to what can be done for one side without changing the other.
Megaultragianteye has a point IMO that in term of experience it wouldn't do to confuse the results as only being the amp's behavior.

Etymotic used the resistors for tuning of the FR. And it's really not important, but the er4s was around 100ohm in total with one 75ohm? resistor per channel for the old er4s.

 

[bigshot]

A similar thing exists at the top end. I used to restore classical 78s and one very good trick was to include a little bed of high frequency hiss. The recording didn’t include any content in that frequency band, but the small bed of hiss gave the ear something to hear so it wouldn’t be noticed as missing. It was pretty amazing how muffled sounding recordings would open up with just the addition of well placed hiss. Brass and strings would sound much better.

It sounds like Vnandor’s headphones already have a mid bass hump. There’s only so much it can help. More isn’t necessarily better. I haven’t had much luck EQing up sub bass when there isn’t any sub bass to dial up. You’re fortunate that there’s enough to EQ. HD600s are good headphones with more latitude than a lot of others.

You’re absolutely right that sub bass with speakers requires a good room and proper arrangement of the system in the room. Speakers work best when they’re free standing, away from walls. Corners are the worst, I’ve found.

 

[gregorio]

I can understand that the midbass hump can work in some limited scenarios. Specifically, when no sub-bass information is present, as commonly the case for classical music.
In general, for electronic recordings with sub-bass lines, even slight overemphasis of mid-bass can be ruinous, and people outcry about it in other forums.

There’s no magic bullet, it may work with some masters and not with others. As a rough rule (EG. Fairly often not the case), it won’t work well with very heavily compressed masters and electronic music is commonly the most compressed. Although few consumers will be aware because they don’t get to see it, the final mix of most popular genres typically has it’s peak level at around 80Hz (between 60-100Hz), which is largely due to the kick drum, although the bass guitar also contributes greatly. Once the mastering is complete the peak level is spread across a wider spectrum and commonly from around 80Hz to 200Hz and sometimes even centred around 200Hz. If you think about the use of compression, it’s obvious why. A (full band) compressor reduces the peaks and then make-up gain can be applied, to “make-up” for the gain that’s been reduced. So if our final mix has its peaks around 80Hz, it’s around 80Hz that the compressor will primarily reduce and make-up gain brings up the level of the whole mix. Our around 80Hz content is roughly back where it started but everything else is significantly louder which means the balance is out. We probably need to make that area a bit louder but we can’t because it’s already at peak and more compression is not going to help, so what do we do? The answer to this question is one of the main areas that separates the men from the boys when it comes to mastering engineers (of many popular genres), because there’s not one single answer but a whole raft of potential solutions and in the vast majority of cases, it’s an individual and often very subtly different blend of “tricks” appropriate for each song. If a track/song is part of the “loudness wars” then pretty much all of these “tricks” have been pushed to (or maybe beyond) their limits. So applying the simple trick of adding more to the “bass hump”, even just a small amount, is likely to make the whole thing sound noticeably worse because that simplest of “tricks” has already been applied during mastering very near or at it’s limit.

To give another more precise example: We always used to give all the students an exercise which was to mix a raw recording of a supplied piece of metal genre, with instructions to particularly concentrate on the punchy/loud kick drum emblematic of metal genres. We’d come back after 45mins and usually they’d have a sheepish look because the kick was moderately loud but just a mush and their track probably had half a dozen or more different plug-ins all trying to manipulate the bass region. So first thing we’d do is disable all their plugins, add an EQ plugin, tighten the Q to quite narrow, boost by 10dB and sweep it to find the resonant harmonic of the kick transient, which almost always lives between 1.2kHz and 1.8kHz. Then, lower the boost to around 6dB, add a bit of moderately lazy compression, bring the whole mix back in and then check to see how far the student’s jaw had dropped! They never consider for a second that adding boost so far outside the frequency band they thought they were working with could have such an effect on that band. I’ve had many students double check what I’ve done, because they couldn’t believe it and were searching for some other plug-in (processing the bass) they think I’ve hidden in the routing somewhere.

There’s no rule, it depends on what sort of music you listen to and even with types where it does work well, adding more of a bass hump probably won’t work all the time.

The audio processing part says Waves Audio was taking advantage of this effect as early as 1999.

Yep, I owned Waves MaxxBass back in the day and well before that there were analogue bass enhancers. I had the famous Aphex Aural Exciter with “Big Bottom” in my first studio in the early ‘90’s and other units I know of, were around at least by the mid ‘80’s. Never knew exactly what any of them were doing because it was all trade secrets, we could only guess to an extent by examining a null test. As I mentioned, there’s numerous ways of processing the bass, from as simple and obvious as an EQ boost or multiband compressor to sophisticated dynamic multi-tone synthesis based on various perceptual effects and commonly, several different ones are used in combination.

G

 

[The Jester]

A similar thing exists at the top end. I used to restore classical 78s and one very good trick was to include a little bed of high frequency hiss. The recording didn’t include any content in that frequency band, but the small bed of hiss gave the ear something to hear so it wouldn’t be noticed as missing. It was pretty amazing how muffled sounding recordings would open up with just the addition of well placed hiss. Brass and strings would sound much better.

It sounds like Vnandor’s headphones already have a mid bass hump. There’s only so much it can help. More isn’t necessarily better. I haven’t had much luck EQing up sub bass when there isn’t any sub bass to dial up. You’re fortunate that there’s enough to EQ. HD600s are good headphones with more latitude than a lot of others.

You’re absolutely right that sub bass with speakers requires a good room and proper arrangement of the system in the room. Speakers work best when they’re free standing, away from walls. Corners are the worst, I’ve found.

Interesting,
Some say that RFI in components and cables that are not optimally shielded can result in a similar low level hiss, so someone who swaps out a cable for one with big shiny gold plated connectors and/or less than optimal cable shielding would then perceive it to be “brighter, more airy, more detailed “ etc ?
And on the reverse a well shielded cable with a non metal connector housing like say ABS could minimise the effects ?

Edit:
Just watching the morning news, hope all you guys in the US are OK during the snowstorms …

 

[gregorio]

Some say that RFI in components and cables that are not optimally shielded can result in a similar low level hiss …

Not really, not unless it’s exceptionally badly shielded (and it’s not a balanced cable). I say “not really” because you can hear hiss and other artefacts which should be inaudible if you screw up the gain-staging, screwing up the impedance or power matching can also cause audible hiss.

Bigshot is right, that’s an old trick, used it myself at times, though not when restoring vinyl. Another old trick, not used so much these days with digital recording; if you take white noise and band limit it (around 10kHz - 14kHz) adding it to cymbals really enhances them, ear can’t tell the difference. They used this trick quite often back in the analogue days, because of the nature of tape response and wear while mixing, you’d loose a lot of the high-end and the cymbals would end up sounding dull. Bit of white noise fading out with the cymbal decay, those cymbals got their zing back and sounded “like you were there”

G

 

[bigshot]

Ooo! Good trick for cymbals! Tucking that one away in my bag of tricks!

 

[gregorio]

Good trick for cymbals! Tucking that one away in my bag of tricks!

It’s worth having it in your “bag of tricks” but it’s far more limited in these days of digital recording and mixing, because you don’t loose the high freqs to start with and because the HF is far more accurate/cleaner/detailed with digital. So when I’ve tried it, it was a bit of a “faff” to get it right. Can be an alternative or addition though, when you need a lot of Aural Exciter but that makes it sound a bit too synthetic or phasey.

G

 

[bigshot]

I would use it with transcribing 78s.

 

[The Jester]

Not really, not unless it’s exceptionally badly shielded (and it’s not a balanced cable). I say “not really” because you can hear hiss and other artefacts which should be inaudible if you screw up the gain-staging, screwing up the impedance or power matching can also cause audible hiss.

G

I wasn’t thinking of “audible hiss” but a lower level that may cause artificial brightness, there are more “home audio” components offering balanced connections being released but I’d guess the most common is still single ended RCA’s,
I’ve experienced first hand how invasive RFI can be to sensitive electronics (non audio) and thought it could be of interest here ?

 

[bigshot]

It has to be audible to have an audible effect.

 

[The Jester]

It has to be audible to have an audible effect.

Audible as being able to define it as a definite hiss rather than a low enough level not to be perceived as an independent hiss ?

 

[gregorio]

I wasn’t thinking of “audible hiss” but a lower level that may cause artificial brightness,

If that “artificial brightness” (due to hiss) is audible, then the hiss is audible, it’s just being perceived/identified as something else. In other words, the hiss cannot be inaudible but cause some effect that is audible. With threshold testing for example, it is quite often the case that what is defined as “above the threshold” (audible) is due to the ability to hear some indirect effect of what we’re testing. In a DBT or ABX, it’s only necessary to detect any audible difference, that difference does not have to be identified.

there are more “home audio” components offering balanced connections being released but I’d guess the most common is still single ended RCA’s,

“Balanced connections” reject RFI but are only required under certain circumstances which typically don’t exist in “home audio”, unusually long cable runs and/or unusually high RFI. A single ended connection, modestly shielded will be fine. The obvious exception is transferring digital audio data but then digital connections are virtually always balanced/differential connections.

I’ve experienced first hand how invasive RFI can be to sensitive electronics (non audio) and thought it could be of interest here ?

Indeed it can be. But then radio frequencies are by definition in a different spectrum to audio frequencies and it’s obviously incumbent on any consumer audio equipment manufacturer to design their equipment to function properly in consumer environments.

G