Impact of receivers / processors with built in EQ

[pzannucci]

Ok, dumb questions but what is the thought on speaker manufacturers building speakers that present a flat response anymore?

 

Now that receiver and processor manufactures have a lot of horsepower to allow for modifications of a speaker's response in room, does anyone feel this will have an adverse affect on the ACTUAL speaker's frequency / phase response on newly designed speakers?  You know, assuming the front end electronics can smooth out the warts?

 

The reason for this being in the two channel forum: What do you think the affect will be on us that use two channel systems and rely on raw power and finesse of the front end components with smooth frequency response from the speakers in our two channel systems on future designs?

 

I am noticing a lot of folks talking about how a speaker sounds but many are using receivers with some auto-eq enabled.  Manufacturers can look at this as the target audience.  

 

Thoughts?

[Deang]

I think responsible manufactures will always try to get the response as smooth as they can. 

 

Besides, it needs to start flat so I know what I’m screwing up. 

[garyrc]

@pzannucci,

 

Flat in whose room?

Flat in an anechoic chamber?

Flat on axis, or 20, 30, 50 degrees off?

 

Because you are someone with over 2,000 posts, I realize you know this stuff, so most of the below is for less experienced members.

 

I'd rather see speaker makers concentrate on dynamics and low distortion, while electronics people develop better room correction.

 

If we can start with a speaker with low modulation distortion and low harmonic distortion, good transient response, etc., and then use automated room EQ and room treatment to provide smooth response at the listening position, or somewhat flat response at several listening positions, I think we would be better off.   I think automated room EQ  will get better over the next few years.  At the moment, Audyssey has improved my response (as assessed by ear and by instruments) quite a bit.  It uses hundreds of correction points.

 

PWK ranked low distortion high in importance, and smoothness of frequency response as somewhat lower in importance.

 

Historically, notably flat speakers have often had relatively high distortion.  The best horn loaded speakers of the past and present have had low distortion.  Direct radiators haven't done as well.  "Acoustic suspension" speakers tend to sound muddy and sometimes discordant to my ear, perhaps because of modulation distortion arising from wide excursion.  An abundance of spurious side bands not harmonically related to the original tones can sound pretty horrible.  IM distortion of "good" speakers has often hovered around 7% at very high SPL (e.g., 105 dB, the reference peak (full scale) at the MLP for THX/Dolby, etc. for speakers other than subwoofers).   Grabbing an old issue of Audio at random, I see a Fried Studio 4 measuring at 10% IM at 105 dB.  The Klipschorn, also measured by Audio, at the same 105 dB output, measured 1.75%.   As for the usually less noxious Harmonic Distortion (also at 105 dB), The Fried had 4% and the Klipschorn had 0.25%. 

 

In my room, A/B switching between Audyssey Flat On and Off, produces greater clarity in the On position, as well as smoother response.   At the MLP, we get +/- 2.3 dB from about 50 Hz to 15 K Hz, and +/- 1.15 dB from 325 Hz to 12K Hz.  I generally use some bass boost below about 250 Hz, and the speakers are not as flat below 50 Hz, but the bass, without the subwoofer in play, extends to 25 Hz, or so.

 

 

[pzannucci]

3 hours ago, garyrc said:

@pzannucci,

 

Flat in whose room?

Flat in an anechoic chamber?

Flat on axis, or 20, 30, 50 degrees off?

 

Because you are someone with over 2,000 posts, I realize you know this stuff, so most of the below is for less experienced members.

 

I'd rather see speaker makers concentrate on dynamics and low distortion, while electronics people develop better room correction.

 

 

 

 

You are correct with your questions but you only have so much of a deviation that can be made in the digital domain.

This was not a question of if digital eq is effective or not but do we think it will impact the quality of moderate level speakers.  Of course I would assume any manufacturer producing speakers over a few grand a piece would try to have a target curve so as Deang said, we know how much we mess it up.  But in reality, the less work the digital eq should have to do to resolve room problems, the better and more effective it should be in providing excellent sound  That means starting reasonably good.

 

The key is that I don't want to be required to use digital eq so I don't want the manufacturers messing things up in my minimalistic 2 channel system.  I'd like to get perspectives on if things are still getting better for 2 channel or is digital eq the only way forward. 

[YK Thom]

I haven’t really noticed manufacturers of passive speakers deviating from the flat response goal. The construction of speakers designed specifically for a relationship with/dependence on DSP/EQ seems to be much more a factor with smaller, generally powered systems (aka lifestyle systems).

[Shakeydeal]

Most serious listeners aren't depending on DSP and/or equalizers to "fix" speaker response. And as said above, most passive speaker manufacturers strive for flat anechoic response, but if you heard that kind of actual sound in your room, you wouldn't like it.

 

Shakey

[Max2]

The room correction in most AVR's is a step back in all but the most horribly setup and shaped rooms IMO. I think it is fine for movies to help with dialogue and spacing and whatnot, but the SNR and THD goes up when you send your signal through the spaghetti strainer chip boosting and cutting and changing timing, etc etc.  I have never ever heard room correction make music sound better in a two channel or multi channel setup, but I welcome the opportunity to be enlightened on it, but Im not holding my breath.  In a great environment, you still cant beat an undisturbed signal going from A to B.

[Edgar]

EQ is like medication -- just the right amount can make you feel better, but too much can kill you.

 

A modest amount of broad boost or cut that flattens a loudspeaker's response is usually OK. Trying to make an 8" woofer extend down to 20 Hz is not.

 

Some of the old-time manufacturers made "cut-only" EQ, because they found that people didn't understand what they were doing and tried to boost their way out of comb filtering and natural notches caused by cancellation. You can accomplish more with a few hundred dollars in acoustical treatment than you can with a supercomputer trying to EQ a bad room.

 

My opinion as a signal processing engineer: Digital EQ can do amazing things, but at some point it becomes "fun with numbers" because nobody in their right mind would want to exploit those extreme capabilities.

 

"Observe due measure; moderation is best in all things." - Hesiod (c.700 bc)

[YK Thom]

13 hours ago, Max2 said:

The room correction in most AVR's is a step back in all but the most horribly setup and shaped rooms IMO. I think it is fine for movies to help with dialogue and spacing and whatnot, but the SNR and THD goes up when you send your signal through the spaghetti strainer chip boosting and cutting and changing timing, etc etc.  I have never ever heard room correction make music sound better in a two channel or multi channel setup, but I welcome the opportunity to be enlightened on it, but Im not holding my breath.  In a great environment, you still cant beat an undisturbed signal going from A to B.

Your theorem is nullified by the great environment qualification. Such environments are rare to nonexistent  in domestic living spaces. I hear room correction make sound better each time I turn on my system.

[garyrc]

22 minutes ago, YK Thom said:

Your theorem is nullified by the great environment qualification. Such environments are rare to nonexistent  in domestic living spaces. I hear room correction make sound better each time I turn on my system.

 

Same here.  When I switch back and forth between Audyssey ON and Audyssey OFF, the ON position sounds better balanced, and significantly clearer.   There is no audible noise until I get within about 8 feet of the speakers (normal listening position 12 to 16 feet), and then it is a soft hiss.  If anything, there is noticeably less distortion.  The room is treated, but Audyssey made a greater difference than room treatment did.

 

It takes a while to get it set up just right initially.  Some people may give up too early.  I had to use a somewhat closer cluster of the 8 microphone positions than the diagram showed.  The company eventually adopted a closer cluster, similar to mine.  My Klipschorns never sounded as good as they do with Audyssey.  Same with the modified Belle Klipsch center channel and the Heresy II surrounds. 

[Kalifornian]

I second that Audyssey ON makes my music sound significantly better with ZERO added noise.  But that is just for ME. 

[willland]

4 hours ago, garyrc said:

Same here.  When I switch back and forth between Audyssey ON and Audyssey OFF, the ON position sounds better balanced, and significantly clearer.

My experience also, especially when I engage the proprietary NAD EQ curve from my T-175HD pre/pro.

 

Bill

[Chris A]

On 11/28/2018 at 10:07 PM, pzannucci said:

The key is that I don't want to be required to use digital eq so I don't want the manufacturers messing things up in my minimalistic 2 channel system.  I'd like to get perspectives on if things are still getting better for 2 channel or is digital eq the only way forward. 

This statement seems a bit conflicted with itself...and your own personal situation, I believe.  I'd guess that you personally have enough loudspeakers to last more than your lifetime already--perhaps multiple lifetimes.  So I doubt that you're talking about your personal needs--but rather more about "the way the world is going" (i.e., with or without your approval). 

 

It's also a statement of how passive-centric that you view the home hi-fi audio world.  When you think about the situation as it now stands, this is an artifact of where you've come from, not how someone starting out fresh from scratch would do things.  The handwriting is on the wall, it seems.  If this is what you're afraid of, I recommend anti-panic medication--it's going to happen (to some extent).  There is already a segment of the audio world that operates the way that you don't want them to.  Bose has been doing it for 50 years already with their 901 "active equalizer".  And there are a lot of Bose owners out there, some of which believe that they're listening to hi-fi. 

 

Personally, I've never liked how passive crossovers work:

• attenuation only--just like pushing down on the engine accelerator and using the brake to control the speed in an automobile,
• no real correction capability is available for time misalignments (which are usually pretty horrible for any horn-loaded drivers)
• thermal heating problems,
• capacitor aging problems,
• the inability of the connected amplifier to control the individual drivers because of the decoupling effect of the passive crossover network in-between,
• the sensitivity to loudspeaker wire capacitance,
• back EMF bleed-over from the woofer into the higher frequency channels,
• the inability to change anything with the drivers or to repair/replace drivers in the future with slightly differing T/S parameters,
• the long development time/resources required to achieve an initial passive crossover design (a highly coupled design approach that's not very productive)
• etc., etc. 

Multi-amping and DSP active crossovers make a whole lot more sense to someone starting out without the baggage of the past making the decisions for him/her.  You get full control of what the drivers are individually doing, isolation of the drivers from each other, full control of time alignments and EQ for dialing in the room response, lossless operation requiring much lower power amplifiers, and the possibility of enticing the owner into the tweaking process (a good thing). It's also becoming much cheaper to develop and implement for the same "hi-fi" sound quality value.  In short, the downside is easy to accept given all the advantages.

 

I believe that what you're actually concerned about is judgment and taste in loudspeaker design.  What I've found is that, like the RIAA member record companies that have consistently trashed their hi-fi music album offerings, there is nothing standing in the way of someone doing the same thing in loudspeaker design.  The real question is "how quickly is the change going to occur?".  I think the only thing that is slowing it down is the culture of the present consumers of hi-fi, most of which are aging into retirement.  There will probably be holdover "retro" consumers for a long time.  Will it represent the bulk of the marketplace?  I don't believe so.  Only the listening experience is the acid test, and consumers will eventually forget about how it's achieved.  So if someone finds a way to abuse the acoustic drivers into playing whatever type of electronica that exists in the future (and still call it "hi-fi"), it's going to happen, and the only question is how many consumers join in to buy those loudspeaker abominations. 

 

If there remains any semblance of an "audiophile hi-fi community" in the future (an interesting question without a sure answer), there may be loudspeakers available that don't over-rely on digital EQ correction.  Right now, there seems to be a fair amount of restraint by the major loudspeaker manufacturers of better quality products to in fact under-use digital EQ.  That will change once the companies can convince their customers that finite life buying scenarios are in their best interest (which as we both know, they're not).  Currently, I see many subwoofers (direct radiating) that the members of this forum own--that fail in large percentages of population.  Their loudspeakers also fail due to overload, but not at a rate like subwoofers.   Then more cheap direct radiating subwoofers are bought to replace them, and the cycle repeats--to the benefit of the companies producing these underdesigned products.  It's just like planned obsolescence in automobile design.

 

As far as where hi-fi is going, your concept of a "minimalistic two-channel system" is also something that is inherited from your past--not the present for new loudspeaker design engineers or younger consumers.  The initial age of hi-fi audio was the 1950s-1980s.  Things are not the same as they were, and the market's focus on "stereo-only" is going away at some point (if it hasn't already with HT offerings like the Reference series, etc., which presently represents the bulk of the consumer buying public.)

 

Chris

[Edgar]

1 hour ago, Chris A said:

As far as where hi-fi is going, your concept of a "minimalistic two-channel system" is also something that is inherited from your past--not the present for new loudspeaker design engineers or younger consumers.  The initial age of hi-fi audio was the 1950s-1980s.  Things are not the same as they were ...

 

I draw an analogy with automobiles. Modern automobiles, with driver-assistance capabilities -- anti-lock brakes, brake force distribution, traction control, stability control, roll mitigation, blind spot monitoring, forward collision warning and braking, tire pressure monitoring, etc. -- as well as improved design and execution of that design, just keep getting better by every objective criterion. They are quicker, faster, more efficient, safer, longer-lasting, and just plain better than anything previous. Still, there is a visceral delight in driving an old-time auto that had none of those things. It's not better; it's different.

 

In the same way, audio just keeps getting better. But there will always be a special charm associated with dragging a rock across a piece of vinyl plastic, amplifying those signals with a single-ended tube amp, and playing it all through a fully passive system. It won't be better; it will be different.

 

I run a state-of-the-art digital system in my home. The sound quality can be amazing at times. But my father left me a single Jensen H-222 coaxial driver that produces delightful sounds. It's probably not high-fidelity by any objective measurement, but I find that I can enjoy it as much as the digital system under the right circumstances. And regardless of where audio technology takes us, there will always be a few of us who still appreciate that.

[Chris A]

That comment about nostalgia that got me thinking. All my nostalgia in audio is experienced with old music (i.e., classical)--but played on modern instruments and recordings using modern interpretations.  The old recordings--well, they capture notable musicians' performances but rarely do I enjoy the recording itself, rather the musician's interpretations. I'd rather have the best digital recordings or restorations of these performances.  I try to minimize attachments to ancient hardware.  I don't own vintage automobiles, radios, loudspeakers, audio electronics, or even musical instruments.  That kind of nostalgia is best left others: life is short enough as is to focus on what's already happened.

 

Chris

[Max2]

9 hours ago, YK Thom said:

Your theorem is nullified by the great environment qualification. Such environments are rare to nonexistent  in domestic living spaces. I hear room correction make sound better each time I turn on my system.

 

 

 

 

9 hours ago, garyrc said:

 

Same here.  When I switch back and forth between Audyssey ON and Audyssey OFF, the ON position sounds better balanced, and significantly clearer.   There is no audible noise until I get within about 8 feet of the speakers (normal listening position 12 to 16 feet), and then it is a soft hiss.  If anything, there is noticeably less distortion.  The room is treated, but Audyssey made a greater difference than room treatment did.

 

It takes a while to get it set up just right initially.  Some people may give up too early.  I had to use a somewhat closer cluster of the 8 microphone positions than the diagram showed.  The company eventually adopted a closer cluster, similar to mine.  My Klipschorns never sounded as good as they do with Audyssey.  Same with the modified Belle Klipsch center channel and the Heresy II surrounds. 

 

7 hours ago, Kalifornian said:

I second that Audyssey ON makes my music sound significantly better with ZERO added noise.  But that is just for ME. 

 

That's great its working out for you guys.   It degrades my music content and it doesn't matter if its Blu ray audio, DVDA, a lossless ALAC or FLAC file or a 128K ugly mess.  The highs turn shrill, broke up and distorted, the mid sounds really jagged and it is immediately noticeable.  The sound is like I just swapped my amp with a very cheap power source bridged at 2 ohms.   I have spent so many hours running it with two different mics and tripod over and over. Finally after learning that the filters actually do compromise the signal, I gave up. Now my room is heavily treated and quite dead so to speak and I spend most of my time at less than a watt which I think allows you to actually hear things in content.    Everyone should trust their ears, but what Audyssey does to my content is flat out horrid when it comes to music. 

 

Do you guys run the dynamic EQ,  straight Audyssey or use the Flat settings?   

[Max2]

25 minutes ago, Chris A said:

That comment about nostalgia that got me thinking. All my nostalgia in audio is experienced with old music (i.e., classical)--but played on modern instruments and recordings using modern interpretations.  The old recordings--well, they capture notable musicians' performances but rarely do I enjoy the recording itself, rather the musician's interpretations. I'd rather have the best digital recordings or restorations of these performances.  I try to minimize attachments to ancient hardware.  I don't own vintage automobiles, radios, loudspeakers, audio electronics, or even musical instruments.  That kind of nostalgia is best left others: life is short enough as is to focus on what's already happened.

 

Chris

I rely on a lot of the music  that I have been listening to all my life.  The various recordings give me a base to somewhat make a judgement by. Its pretty exciting to me to notice something in content that has not been revealed to your ears for decades and decades.  When I added 100 square foot of panels in my listening room, that's when I finally could make some real calls on my system improvements by ear and some by numbers which I believe you had a hand with years ago, helping me kill reverb and echo issues. 

[Kalifornian]

Straight Audyssey with no other "enhancements" other than an occassional tone control with specific recordings.  I played Yessss yesterday on vinyl "Starship Trooper" and it was awesome.  Immediately played it again on Tidal and it was a whole new (way better) experience.  I got into Klipsch for the retro, analog, simplistic stereo listening, but moved on to modern digital with Klipsch for the clean pure beautiful sound that Klipsch can truly make.

[Chris A]

43 minutes ago, Max2 said:

That's great its working out for you guys.   It degrades my music content...

It does that for me, too (Audyssey MultEQ XT--using any mode). My listening room is probably not as big of a challenge as yours.  When you look at the assumptions that these firmware packages are making, then you'll probably understand why it can go off track so easily.  I believe that more user input on the description of where the loudspeakers, walls and furniture are located, and the exact type of loudspeakers you're using would significantly help these automatic packages work much better, but it would require a bunch more input from the user. 

 

I do it myself using REW, a UMIK-1 microphone, and the DSP crossovers (Xilica XP8080, Dx38),  placing the microphone at each loudspeaker one at a time--one sweep for each loudspeaker--update the EQ settings, then a check sweep--and having the good sense to know what to look for in the data (i.e., ignoring the effects of room and nearfield reflections).  The results are like the difference between the living and the dead.  Audyssey tells me about the measured channel distances, which I also use my judgment to set in the 5.1 array delays (Audyssey always gets the subwoofer distance wrong).  A hand-held SPL meter measures the relative channel gains for a quick manual update each time something changes in the setup. 

 

Chris

[Max2]

4 minutes ago, Chris A said:

It does that for me, too (Audyssey MultEQ XT--using any mode). My listening room is probably not as big of a challenge as yours.  When you look at the assumptions that these firmware packages are making, then you'll probably understand why it can go off track so easily.  I believe that more user input on the description of where the loudspeakers, walls and furniture are located, and the exact type of loudspeakers you're using would significantly help these automatic packages work much better, but it would require a bunch more input from the user. 

 

I do it myself using REW, a UMIK-1 microphone, and DSP the crossovers (Xilica XP8080, Dx38),  placing the microphone at each loudspeaker one at a time--one sweep for each loudspeaker--update the EQ settings, then a check sweep--and having the good sense to know what to look for in the data (i.e., ignoring the effects of room and nearfield reflections).  The results are like the difference between the living and the dead.  Audyssey tells me about the measured channel distances, which I also use my judgment to set in the 5.1 array delays (Audyssey always gets the subwoofer distance wrong).  A hand-held SPL meter measures the relative channel gains for a quick manual update each time something changes in the setup. 

 

Chris

I checked out the Xilica specs from the other thread you were posting in and they are very impressive to say the least. You certainly don't have to worry about the unit leaving any dirt around even with crazy quiet amps and pre's.    One day, I will make the active plunge, but not until I have Jubs and find a home for some pretty modded K's I have invested in. Hindsight, I should have gone the Jub route and could have with all my K add ons.  However, I do like the accuracy and details of these K's and 12' off is pretty revealing. The grass is always greener, especially when Jubs are sitting on it