Equalizer in a Hi Fi system

My approach to all this would remain digital for room correction (mids down). Digital or analog for bass tone shaping/ bass boost. ANALOG ONLY for treble tone boost. 

“The problem with 64 bit floating point is that as the signal gets smaller, the resolution changes, and this creates noise floor modulation. OK so we are talking about over 300dB of innate resolution, but this is subjectively significant noise floor modulation and is audible. Moreover, as a signal disappears into the noise floor, it will be treated differently whether there are larger signals present or not. Now you may argue that these errors are very small but at the end of the day, it's about sound quality, and to me these errors are very significant subjectively. And you only need to look at the Mojo 2 thread to see the very positive comments about the EQ compared to traditional 64b FP EQ.

Additionally, a very important feature is the EQ running at 705/768 or 16FS with all the internal nodes being noise shaped. Without the noise shaping, I would need much more bit depth than 104 bits. This could turn into a significant design problem for me when doing EQ for pro audio. If they process at 192k or greater, I can use noise shaping; but doing EQ completely transparently at 44.1k could be a major headache. Incidently, the benefit of noise shaping the internal truncation errors is that the filter still functions for signals well below the bit depth of the system, as errors are never lost - just re-cycled.”

@mijostyn the above is just released post by Rob Watts himself on Watts Up?… thread on Head Fi  in which he responds directly to my query…and to you most importantly, as I pasted what you said there  

“So Robb. Can I infer here that digital is not all the way there yet when it comes to tonally adding a treble boost, as compared with best studio analog hardware? Specifically talking about treble boost here, the “air band” “

The above is my follow up query to Rob Watts. I will post his response as soon as it becomes available. 

“EQ alone cannot give perfect natural timbre experience ...Physical acoustics is needed too ...”. agreed!!
@mahgister , I have not by any stretch been ignoring your keen and excellent insights. I am just hyper focused on the one aspect of this discussion, namely digital vs analog EQ and where each works best. 

“Treble may be easier in a digital EQ implementation environment (from a programming viewpoint? I am only a tweaking audiophile, no engineer. But from my perspective on the hi fi playback end, treble EQ in its final sonic resultant SQ is HARDER to get right. I spent years to find the best audiophile listening solution to rolled off treble recordings. Your Mojo 2 is the best digital solution I’ve ever heard. Will you be implementing it in pricier desktop non portable designs? The best analog solution for treble roll off for me for the last 10 years remains a Charter Oak PEQ-1 in both my loudspeaker chain and my headphone chain. It leaves the whole frequency spectrum unmolested while creating the most beautiful air lifts that really breathe life into the appropriate recording. I think the studio engineers quite honestly are on to something.”

Above is my response to Rob Watts

His response is interesting:

”I am afraid I don't know the answer to that for sure - apart from knowing conventional EQ is subjectively flawed. I know a lot of recording engineers prefer analogue desks (using DACs and ADCs with analogue EQ), saying they sound better. How much is down to preferring distortion, or how much is down to digital EQ being poor, I don't know. I suspect it's a mixture of both.

Treble EQ is much easier than bass EQ, as the bi-quad coefficients are large values. The largest problems occur with bass - some of the coefficients are very small. So that small value once truncated and then fed back creates significant errors that then accumulate. With IIR filters, the signal is infinitely fed back (hence IIR meaning infinite impulse response). But if the signal is truncated away to zero, then the IIR is no longer functioning as a filter for that signal.”

If anyone wants to see this it’s at Head Fi.  Thread entitled Watts Up…?

Now we are going circular argument, dog chasing tail. . I won’t try to convince you further. Please though, we must not conflate room correction digital EQ with tone control!  You have already said you never boost treble with your digital applications. So I know in that all that I need to know. (Namely that digital treble boost is quite audibly inferior.) I DO like that you attempt to get your amp loudspeaker synergy to a measured flat out to 20khz. That’s obviously ideal for treble extension. The less EQ the better, of course. However, you are just another audiophile who knows everything there is to know about room correction/ phase/timing corrective applications (which is great), but will never know the joys of the analog air band boost. That’s ok 😊. At least Miro knows!

incidentally, I believe digital “tampering” with all these variables creates unnatural sound and more problems than good. Get a good listening room and tonally adjust with an MQ112, Vintage Skyline, Charter Oak or whatever the analog choice and THAT delivers the best sound!  I’ve compared my home experience with 100,000 dollar systems in perfect rooms and prefer mine with EVERY recording, good or bad. 

I’m not mad at all. Just adamant that I know what I hear is universally true. I’ve had too many people tell me my stereo sounds absolutely surreal to believe otherwise. You will never ever hear Pink Floyd Echoes from album Meddle cause your friend who’s an avid concert goer to sit bolt upright and state “oh my god, it sounds like you’re in the studio with them!”  
not mad @mahgister , just ADAMANT. By the way, the BACCH concept is fascinating but would have to hear to believe in it of course. 

I will “buy and try” so long as a return policy for full refund.   
Yes, ears (listening) first priority. In the end that’s all that matters. Psychoacoustic theory, Fourier, charts, graphs, timing vs amplitude, crosstalk…the lists goes on but all largely mentioned here…all important tools but ultimately in and of themselves can not be assumed in their implementation to create the “perfect “ acoustic experience. (We all know stereo is inherently flawed.)  No one here has elaborated more on this than @mahgister   “The proof is in the pudding.”  I believe everyone here has a trained ear and is an astute listener. Or they wouldn’t be here in the first place. Trust your ears and LISTEN to new applications. Explore by listening.  
I am willing for the love and fun of the hobby to try a BACCH filter preamp and or DEQX system in my home. @mijostyn , are you willing to try a MQ112 or better yet a piece like Miro’s Vintage Skyline in your home?  I will bet you’re not. I see you as @mahgister does. As somebody who placed the ultimate trust in the digital tools and theory behind them first and the listening second. Don’t get me wrong. I’m sure you’ve got good listening ears. Be adventurous and try a different approach and you might be shocked that there are other and for some recordings (particularly older classics) BETTER ways to hear them. 

“Well I can confirm what others have said here about the Michelangelo. It's absolutely insane. It just makes music sound like a record like nothing ever heard. Glorious highs, thick mids, deep usable lows. I redid a couple masters that I had done recently and the pre-Michealangelo versions sound truly lame next to the new ones. What's funny is the original masters always sound fine when you listen to them on their own. Then after hearing the MA version and going back...it's just sad.”

Another great quote from Gearspace thread. How can I NOT buy this magic box?  When I bought the CO in ‘13 the reviewers there called it a magic box too. But not nearly to the degree of the MA. I must acquire this piece!

@mirolab , no worries for coloration if one can dial that to a minimum as on this device. After watching the video, I’m impressed with EVERY dial on the piece. Including the “Agression” Or color dial. I have read a lot of Gearspace threads on pieces. Never heard one raved about there so much as this one. I spoke to the owner Chris today and I plan on having him build me one. He said coming from the CO and the way I’m using that that it will fit in very well with my system. 

@mijostyn have you tried in your extensive and impressive past putting a professional mastering equalizer in your chain?  You said you tried analog but didn’t elaborate. What analog EQ did you try?  As you well know, not all analog EQs are created equal. Incidentally I am a doctor too. I’m a family practitioner. What are you?

The ONLY system I’ve ever heard that I preferred flat over miy setup EQd  (and I’ve heard many) was in Audible Images dedicated showroom which Ed meticulously crafted to be as close to perfect as possible. The system was Dan d’Agostino amplification driving Sonus Faber Olympica III’s. The end to end full spectrum extension was unrivaled. The sound reproduction was more pristine, detailed, airy, dimensional, tactile, dynamic and FUN ENGAGING than anything I’ve ever heard. It’s the ONLY system that caused me to take pause with mine. The ONLY. @mijostyn i am willing to BET you have not tried certain renowned for air band professional mastering applications in a home hi fi. I KNOW you haven’t because after 6 f@cking pages of this you refuse to comment on the specific topic. You have had a lot to say, but I’ve never heard you say “I have tried adding air to my recordings” with a Knif Soma or a Manley Massive Passive or a classic Pultec design EQ or a Charter Oak or a Maag or a Skyline or Chandler, Maselec, Millennia, Avalon.  The list goes on. Until I’ve heard you specifically say it, then you haven’t done it. So stop being arrogant in putting down things you haven’t tried. 

Christ, as Miro said pages ago, you think you know something the sound engineers that make your recordings shine DONT know?!  You think they are full of it and wrong when they say for finishing touches and air band in the mastering studio that analog sounds better?  You think Mark Levinson’s cello palette discussion is poop?

Give me a f*cking break!!!  Oh and Rob Watts is an idiot too. @mahgister , now I’m mad!  As I’ve said earlier, directly answer the question!!! WHAT SPECIFIC ANALOG DEVICE DID YOU PUT IN YOUR CHAIN?!

@mahgister , I don’t believe he has tried what Miro and I have tried. I am pressing him for a specific answer because Miro and I are really on to something and I want others to try and he is blanket discrediting us with his snide comments about digital being better than analog for ALL applications. It’s just not right. It’s just not true!

Audiophiles are fearful of treble boost because of people like @mijostyn discrediting without trying the studio proven methods that really really work well in the home too. How can I get my passion and experience with this one topic out there for others to try when he keeps running it down without personal experience?  It’s not right. 

There is studio mastering gear that is built of the quality of summit fi hi fi gear that goes new for upwards of 9-12 thousand dollars. 

Analog is FAR from antique and its use is alive and well in recording studios across the globe. IT’s technology has advanced too. Just like digital. I’m sorry @mijostyn , but on this one topic you just, frankly, don’t know what the hell you’re talking about. 

Exactly @mahgister !

@mijostyn do you realize the build quality of these high end studio components actually always has set the benchmark and the bar for quality for audiophile gear?  Where do you think home hi fi is spawned from?  THE RECORDING STUDIO!

If you were right, why would McIntosh roll out a brand new 8 band ANALOG EQ for a cool 3 grand?  Please cease and desist with your lies and falsehoods. 

@jtcf , happy to be of help. Word of caution on Charter Oak. I have a lot to say about older generation CO vs newer ones made in CA. The Deming era ones are better sounding. I’ve had both in my rig. I returned a new CA made Charter Oak to get an older gen one used from Austria on Reverb. There is still one used one with the right age serial number on Reverb but its volume pots are now detented/modded. Deming himself told me he’s not sure that one’s a good one. Otherwise you’re buying new and not the same. I wish Mike still made them but he doesn’t. It’s worth your while to go back and read earlier in this thread everything that @mirolab and myself said about this piece. If I were buying right now, I’d trust Mirolab’s judgement and buy the Vintage Audio Skyline piece. 

“I also would be willing to bet most studios are using digital equipment at this point. The analog stuff is being or has been phased out except in specialty studios dedicated to analog of which there are a few, not including MoFi😏”

@mijostyn , you are frankly in flat out denial over the importance of analog EQ in mastering studios. Please do yourself a favor and research that online. You will see what I mean. 

“Flat is boring and usually too bright. “

If this is true then your system is not flat. Plain and simple 

The best studio analog EQ 9-13 grand all made with the highest quality parts and would rival the best hi fi gear. Research that too online. This should be obvious. I think, anyway 

@mijostyn appreciate your honesty in that you really haven’t tried what I’m talking about. Regarding playing around with various midrange frequencies I , again, prefer to adjust TONE, meaning bass and treble via the principles laid out in the Stereophile article about Levinson and his thoughts on playback EQ as well as the cello palette. I believe once you are with a good room and with high end gear and cabling that you don’t mess with the mids. So I don’t. I prefer to leave THAT to the sound engineers in production, as our gear far more likely to render flat (what artist intends us to hear is heard) in mids. Rolled off issues in treble though, I love to correct with my high end analog EQ. By the way, if one ever DID want to EQ in the mids or presence regions, good studio analog gear does it GREAT. the sound engineers who reviewed my CO online RAVED about how beautiful the 3 K dial sounds. In fact they raved that you can’t make the music sound bad with any dial adjustments on CO. I actually do often dial in a touch of mids on the 1-2 k some. 
listen…@mijostyn…I respect you and your experience and your approach. I bet you’re great at dialing it in digitally. We all have different sound preferences too. Please respect my approach and thoughts. I am a huge advocate of high end treble augmentation when needed (record dependent), and quite honestly I consider myself to have struck gold here with certain analog pieces. And Miro has commented on said analog air band and its beauty as well. Just please don’t make assumptions about gear you’re not that familiar with. I’m careful not do that with you.  Indeed, because I love this hobby so much, I’ll likely get my hands on a DEQX and really learn how it sounds and what it’s good and not so good at so I can be more experienced.

@mijostyn , I am impressed by your aptitude with implementing biamping and crossover techniques. These are things I know little about. I’ll bet your system does indeed sound really great. Probably different than mine. I might could beat you on some recordings that are older and lacking in tonality. But really great more modern recordings I’ll bet with the knowledge you’ve applied that your system really shines😊. I still think the analog air band in hi fi is “magic sauce.”  Well anyway, I’d be cool in a parallel universe to switch systems for a stretch and see what we learn. 
so you were an FP as well?  CONGRATS on being retired. So you’re in Fl as well?  Miami?

And @mahgister , your aptitude in articulating psycho acoustic theory blows my mind!  Indeed there are so interesting folks here!

Sorry if I get so intense here. But I’m very very passionate about my approach. I still believe after years of accumulated listening experience with many different hi fi systems that my approach yields a uniquely special and very intoxicating (and yes, very hi fi) sound. 

“I also would be willing to bet most studios are using digital equipment at this point. The analog stuff is being or has been phased out except in specialty studios dedicated to analog of which there are a few, not including MoFi😏”

@mijostyn , ALL studios use digital EQ. More for surgical corrections and more in the mixing phase. The mastering stage is where analog EQ really can shine. You read what Watts said. You’ve read what I’ve said. It’s hugely written about online. It’s fact that many mastering engineers prefer the sonics of analog for broad Q tonal sculpting in the final stages of production. And for treble/air sculpting, there are a few standout pieces that are legendary in the treble region. Maag and Charter Oak have been raved about online. You really don’t see such a love like that for different digital platforms. Not for broad Q treble sculpting. Many mastering engineers will use digital to make some of the curves of changes you make but then add the air with the Maag, for example. Probably some of the best recordings involve this approach. These are the kind of things you’ll read if you chose to do so. 

“EQ is one thing. Proper room correction is another. I use both in my main system. “
totally agreed

@tattooedtrackman , still loving the MQ112?

Yes. Agree with that totally. My system always makes dull records sound better and more fun and engaging. But you’re right. You can put lipstick on a pig, but it’s still a pig😊. Happy Thanksgiving all!

“ Yes I am still loving the MQ112. It is the best accessory that I could have bought to do exactly as it is supposed to do. And I love the looks and quality of it also to blend into my existing ARC components. ”

AWESOME!

I have indeed had my hearing checked. I hear properly up to 15-16 K. Thanks for the suggestion. No issues there. I correct for ROLLED OFF RECORDS. Your knowledge and insights have stimulated me to look in more depth at room corrective digital applications. Hope your stuffing turns out well!

“For $300 you can get yourself a calibrated microphone, computer program and measure your system to see what it is doing. I promise you, you will be very surprised. Flat is a reference point. Units like the DEQX will go there automatically as a starting point. No system/room is flat to begin with and in some cases are so bad even digital EQ can not correct it all the way.”

I have no doubt all this is exactly correct. Well stated

“The vast majority of albums are now recorded digitally and most music is now listened to via digital program sources. It makes no sense to keep going back and forth between digital and analog. In digital you can easily do all the processing without adding any artifact whereas every time you pass the signal through an analog device there is always added artifact. Just a fact of life. However, some people actually like listening to distortion and that is their prerogative.”

This is one of the most hotly contested issues in mastering studios today. The internet is FULL of debate on the merits of passing the signal through a high quality analog circuit to put finishing touches or air on a record. You can call it euphonic distortion. Others call it realism or beauty. Miro says just passing the signal through his Great River (flat) improves the sound. Many studio engineers have said the same online. I know what my ears hear, and I’m AS MUCH excited by what I hear in my system now as I was several years ago when I started with the Charter Oak. The passion says it all. And my previous anecdotes should be instructive as well. Let’s just agree to disagree on this point.  Happy Thanksgiving!

“I use Electrostatic speakers because their distortion levels are a level of magnitude lower than dynamic speakers if run correctly (no low bass). There are no analog crossovers in my system. RIAA correction is done digitally. I can record vinyl to the hard drive in 192/24 and nobody has been able to tell the difference between the recording and the actual record. Once you are in numbers you can go almost anywhere you want. I use 10th order slopes for the subwoofer crossover, virtually impossible to do in analog. ”

Again, this kind of material stated here tells me you know your stuff, and I’m highly impressed. I think you are on to something as well. I wish I could HEAR your system. I promise to learn more about higher order digital EQ. Right now I’m working through the 1 hour 50 minute video “Understanding the State of the Art of Digital Room Correction” by Accurate Sound on YouTube 

Charter Oak that I have is a very powerful equalizer. In other words you can boost a treble band up to +19 db with NO audible distortion and the resulting SQ is still hi fi, no significant loss of staging, dynamics or image resolution. While in that scenario of full boost that the treble is obviously too much for most records, it still sound GOOD. Still sweet, clean, undistorted, integrated well with the mids to still sound highly musical. It’s just remarkable. Of course, these are the reasons some sound engineers prefer this as the “final act.”  All I can say is I can certainly see why. 

It’s simply intoxicating. I can listen to my favorite music for hours and never get bored. It’s a beautiful thing. 

The right amount of air band in such gear opens up the ENTIRE mix, top to bottom, to better SQ. Timbre improvements too as the missing supra auricular harmonics and highest octave textures that are missing are restored.

Again, sorry the million posts. I’m still impassioned, and when good verbiage to express my listening impressions comes to mind, I have to type it. 

I’ve heard RME dac is a little edgy or a little digital glare or etch. Don’t know if that’s true. I’ve yet to find a digital EQ that tone shapes even close to balanced analog studio EQ. If you try though, I’d love to hear thy impressions!

Perhaps back to what I originally said?  Get the room right and then tonally EQ to your heart’s desire with a Skyline M3D or other great studio analog tool. This particular approach I’ve been in love with for a decade. There must be SOMETHING right about it!  
incidentally, I will still try DEQX as I said I would so I can hear for myself. Also, I just bought a Skyline M3D from Revive Audio folks. CANNOT WAIT to hear how it compares to my Charter Oak. Thanks for the tip, Miro!

Regarding DSP for speaker and room correction:
 

The following is from Ed to me at Audible Images in Melbourne FL. I have heard the best sounding system of any showroom in FL at Ed’s. I trust his judgment and his ear absolutely implicitly. The following is what he said. It leaves open the question of the newer forthcoming DEQX vs Trinnov. It seems Trinnov is the best he’s heard. Here it is:

“ Tim, 
I have tried room EQ with several different products. Audessy, DIRAC , Room Perfect and the Trinnov. In my opinion the room correction is more destructive than corrective. The Trinnov was impressive in its capability to manipulate the sound in every way. However it did not sound very good. We consistently prefer the sound with the room EQ disabled. I can hear the sound quality change for the worse when it is engaged. I typically hear some grain added and slight glare overlaying the sound. I tend to push my customers into letting me place the speakers and subwoofers where they sound best so I usually do not end up with major issues to deal with. I have used the EQ in some subwoofers in certain circumstances with decent results. 
Thanks 
Ed ”

XLR side, we short pins 1 and 3 to tie to shield of a 75 ohm coax cable to the RCA. Pin 2 on the XLR ties directly to the center pin of the RCA. 

The cables are ready to go. Full unity gain without any box in between. You don’t want ANY other box in the circuit. If had done all that in the beginning. When I discovered the Mogami Gold and that I didn’t need a box, SQ took a huge leap forward. 
how exciting!!  Which piece? Price range? New or used?

@scottwheel , what digital system do you use?

And @tattooedtrackman , do you use digital EQ as well as the analog MQ112?

@scottwheel was commenting specifically on DIGITAL EQ. your MQ112 (for those catching up) is ANALOG

So @scottwheel , you have a BACCH preamp?  And obviously you like?  I may try this before playing with DEQX.  we are in the golden age!  So much good technology!