The Miracle of EQ, or "How I Learned to Stop Worrying and Love my LCD2C Again"



You have a rabbit hole within a rabbit hole within a rabbit hole here … first there are the issues pertaining to applying EQ in the first place.

Then you can go further and start spending more time considering the strengths of different approaches and specific tools.

And then even within a single tool, especially the more sophisticated ones, there are myriad little controls and settings that effect exactly how your chosen EQ points/values are actually applied/filtered behind the scenes.

Using a non-specifically EQ example, I tend to find that with any DAC that has selectable filters I will often start on a minimum-phase filter and in fairly short order wind up settling on a linear-phase filter as my preference. The longer I listen, the more I find linear-phase to work better - especially in terms of overall listening fatigue, which occurs much more often for me with minimum-phase approaches (though for studio work other factors, principally latency, can trump that).

I’m lucky in that I tend to find things I like, get them setup the way I enjoy them, and after an initial period of fiddling around to get to those points, am happy to leave them alone and enjoy the music.


Honestly this is how I feel about most things! I tinker initially until I’m happy then leave it alone…unless I learn something new that is worth looking into then the cycle starts again lol


It is flat out insidious (this disease).


All I was saying was that the phase shift issues exist in all analog filters and the only way around it is to do the filtering in the digital domain. In the digital domain you then have to deal with the issues when converting to PCM digital, processing and then reconverting back to analog (ADC -> DAC)…that’s all.


I think you’re picturing something like this, right? @Torq was just saying that if your source material is already digital you don’t need something like this and can just do the DSP work in software (or hardware, but the point is that you’re already in the digital domain). There’s no ADC step, just the final DAC step.

One thing that I find interesting/funny about recent analog is that IIRC most contemporary music is recorded and processed digitally, so when listening to vinyl you’re effectively listening to an analog recording of something that went through at least one DAC anyway :slight_smile:


It’s crazy how different the HD58X and the LCD2C sound to me, despite their measured frequency response being pretty darned similar (post-eq):

Even crazier, the measured clarity of the HD58X is higher than the LCD2C. This is true for both C80 and C50:

Furthermore, while I feel like I prefer the HD58X at lower volumes, the clarity actually improves at higher SPL:

@prfallon69 and I were discussing whether the “grain” that we hear in the HD58X is a problem with the headphone or just the headphone exposing information that’s in the recording. As mentioned, I don’t hear this “grain” with the LCD2C even though the frequency response is very similar, so perhaps the difference in clarity is the culprit, which would support @prfallon69’s thinking that it’s the HD58X being more transparent.

Lastly, there’s distortion. I don’t entirely trust my E.A.R.S. for measuring distortion, but it shows that at a reasonable SPL (around 84 dB), the HD58X and LCD2C have extremely similar distortion, which is an impressive showing by the HD58X:

Once you get up to 90 dB, the LCD2C does pull ahead in the bass region.

This is a good example of measurements (or at least a subset of measurements) not telling the whole story.


To me the HD58X has a bit more grain than the other HD6 series and its not the track since I don’t hear any grain with HD800, HE560 or T1gen1 with the same track. Agree that its a good example of measurements not telling the whole story.


Another great post @pwjazz. As I don’t own a measurement rig it’s nice to be able to see the data in black and white/colour. I Also agree in your observation that the HD58X is one of those sneaky headphones that sound better the louder the become. It’s something worth noting if you’re a nudger (nudging the volume up and up) like me. A habbit I am now starting to break for the sake of my ears.



You could be right. I am still trying to figure it out once and for all. As @pwjazz stated the HD58X have great clarity and it could be that they’re picking up something in the recording. Mind you I also noticed it didn’t occur on my HD800.



I wasn’t really thinking about any particular unit, I was just speaking theoretically and stating that the only way to filter the signal without effecting frequencies above and below the effective frequency of the filter is in the digital domain.

My other statement then referred to the fact that digitizing the analog waveform and then converting it back to analog has issues of its own. That is all. I wasn’t thinking about anything other than the effects of filters on the analog waveform.

Personally, I have a Schiit Loki tone control box hooked into my work system:

  1. Toshiba 17 inch laptop
    Windows 10, Foobar 2000 v1.4 w/kernel streaming, ASIO & SACD components
  2. Pangea 0.5 m silver USB cable
  3. Schiit Wyrd USB signal cleaner
  4. Pangea 0.5 m silver USB cable
  5. Schiit Modi Multibit DAC
  6. Kimber 0.5m Hero IC w/WBT connectors
  7. Schiit Loki Tone controls
  8. Kimber 0.5m Hero IC w/WBT connectors
  9. Schiit Lyr2 headphone amp w/Philips 7DJ8 tubes
  10. Focal Clear headphones or HiFiMan He-400S headphones

I find the Loki tone controls to be effective, has very low noise and has little side effects.

I am not one of those purists who hates equalization but it does have its down side.



I could see myself liking the Schiit Loki. It would be nice to be able to adjust the tone and sound with the turn of a knob. I know it’s not exactly a purist approach but anything that gives me better control over sound whilst being relatively simple is a plus in my book. Sadly Schiit products aren’t as easy to come by over in the UK as in the US. I may keep an eye out for one. I can always sell it on.



You should be able to get it here…



Loki is a nice little unit. It does it’s job well. And it’s well priced for what it does. I have one myself, picked up mostly out of curiosity and for when I thought I might put it between my phono-stage on my office turntable and the amp I’m using there.

There are many aesthetic arguments for analog EQ. And in an all-analog system there are some technical ones too. But where your source is digital, in that rig you could avoid the, as you’ve stated various unavoidable vagaries of analog EQ, and just run a software EQ component in Foobar 2000.

No ADC required, and no additional DAC step.

It’d be far more precise, enable many more points, and types, of adjustment, allow for an arbitrary number of preset configurations, and most importantly avoid a bunch of unnecessary analog connections and components (each of which adds signal reflections and losses, no matter how well engineered). And it’d be cheaper as well.

Now, what you do and why you do it is entirely your call - it’s your system and your money. Doesn’t need to be justified.

For me, if I was pointing out the issues with analog EQ I would find it an issue of personal cognitive consistency to then go out of my way to implement it in a system that can use pure software EQ with no downsides other than not having physical knobs to twiddle. Again, no ADC or extra DAC step is needed here, as the signal remains digital until it hits the DAC anyway.


Thanks for the heads up.



It’s funny, despite my willingness to spend what most sane people would consider obscene amounts of money on headphones, I’m also a bit of a value hound. My primary platform for listening, even when stationary, is an LG V20, which I found as an open-box return for about $250. It includes a very competent DAC and powerful enough headphone amplifier on an integrated circuit, expandable storage that allows me to carry my entire collection in FLAC on a 256 GB SD card ($110), a removable and long-lasting battery and a beautiful screen for interfacing with it all (not to mention watching YouTube videos and Netflix movies). For another $10 I bought USB Audio Player Pro, a feature rich audio player whose UI puts my old dedicated Fiio DAP to shame and that can take full advantage of the V20’s DAC, plus stream music from Google Play Music and Tidal. Thanks to a partnership between Toneboosters (a company that specializes in DSP for audio production and playback) I was able to activate a very nice parametric EQ plugin for around $4 and a headphone equalization and simulation plugin (Morphit) for another $4 or so.

I think it’s that last part that most blows my mind, a music player plus high quality DSP for less than $20. Once you have a digital platform to work with (i.e. Android), the opportunities for innovation grow exponentially. Not many people would have the know-how or resources to create, market and support a physical device like the Loki, but a smart kid could put together a cool new music player and start selling it with very little upfront investment other than time. I myself am a software developer with more ideas than time, but when I look at something like the RME ADI-2 DAC, especially features like loudness (volume-sensitive EQ), I find myself wanting to make an audiophile audio player that incorporates those kinds of features. I’ll probably never find the time to do so myself, but someone else could if they wanted to, and I find that exciting.


I’ve been doing some head-to-head comparisons between my HD58X and LCD2C as I tweak the EQ for the LCD2C. I consider the HD58X to sound very realistic (very speaker-like in terms of timbre) and am using that as my target for the LCD2C. What I’m finding is that I can get the tonality of the LCD2C to sound accurate, but there’s still a gap in realism relative to the HD58X which I want to chalk up to poor micro-dynamics messing up the attack and envelope of sounds. Is this what you were getting at?


Yes. Frequency response and timbre are completely principles.


EQ aside, I’m finding that certain sources definitely work better for the LCD2C than others. Right now, I’m enjoying the combination of LG V20 (as DAC) plus the Magni 3 for amplification. The Sabre-based V20 has noticeably better clarity across the frequency spectrum than my Burr-brown Hifiberry. Compared to using the amp built into the V20, the Magni 3 seems to further increases clarity, especially in the lower frequencies.

I never used to believe in differences between DACs, but I’m starting to think that there’s something to it. I might have to get a desktop Sabre DAC to see how I like that.


I can say in my limited time with multiple DACs that it is a thing! It’s just a milder “thing” than say amps and transducers


I’ve gotta agree with you and @pwjazz. Dac’s do add subtleties depending on what make they are. I especially like ESS SABRE based Dac’s for the detail and perceived clarity. As well as brightness I suppose. I will have to try more flavour Dac chipsets. Plus I’ve only ever sampled the relatively cheap end of the spectrum. I know you’ve tried some higher end stuff Tyler.