Upgrade Budget Speakers with DSP: Focus on Directivity!

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[@ErinsAudioCorner]

Bro, next time I come over there I’m gonna crush you in a Street Fighter battle.

[@Bradimus1]

MK II - Scorpion wins!

[@joentell]

We'll see. I'll take you out for sure in MKII. Put your quarters up!

[@aaronmatuszny8856]

Distortion can often happen at very low levels and it does matter, but much like DI it can't be worked around with DSP so its not covered in this vid (good future topic tho). Compression usually comes into play pretty hard & fast: coils heat up & things go pear shaped right away, definitely matters. You can use passive bits to change the top end, but it'll cost you. The people who know how to do this don't work for free. At least if you buy a DSP, you always have that amazing tool.

[@joentell]

This is all true. For this speaker, I also looked at the DSP filters and where they correspond in relation to the THD and compression tests done by Erin. In areas of higher distortion, there is no boost and where there's high compression there's typically a reduction in dB.

[@kewlbug]

DSP is becoming more common and available. I have a DSP on every system in my house (including the garage!) Polk XT15s on small stands and sub under my desk almost a reference quality result. If speaker MFRs are looking for the next big "thing" they should be paying attention to this (directivity and correction)

[@joentell]

I know you! 😉

[@hideopalescent]

I know diy is a lot less popular, but the Parts Express C-note kit speaker (measured at ASR) nails video topic. It is shockingly good with EQ.

[@joentell]

I've built C-notes years ago. I just a look at it on ASR and it does seem like it would take well to EQ. Have you seen the Mechano23 DIY speaker review on ASR? That thing measures extremely well.

[@hideopalescent]

@@joentell I did see it. It's sort of the same formula as the c-note/lsr305 but more refined. I noticed the designer actually made a 2-way crossover using the same c-note drivers that's probably bonkers good (mechano22). I don't like the stock bass shelf tuning and reduced BSC of the c-note. Easily fixable with EQ and I'll gladly take the hit to sensitivity. It's cliche to say this, but it'll make people search for a subwoofer when you give it some juice.

[@EveryDayJay415]

I learned about what early reflections with good directivity index can do by being a fly on the wall between you and Unc Fred. He said his Arendels are like surround sound even in stereo some times, later you said if directivity was good your brain is not confused by hearing reflections and it all clicked. If directivity is good you can rear the sound bouncing off the walls around you yet have it be close enough to the original source that it sounds like surround sound.

[@sudd3660]

i been saying eq is a huge deal for along time. best thing i ever did was getting all sealed speakers and eq them to my liking. i also bought some sealed Arendal's for directivity.

[@kbalfe]

Thanks. Using on axis frequency response is like evaluating a football player with a 50 yard dash. It's a start, but woefully inadequate.

[@ErinsAudioCorner]

👍👍👍

[@dilbyjones]

Yes! Nice approach

[@Bradimus1]

I'm sure the Arendal can also play much louder with less compression/distortion. But if you aren't going to crank it up...

[@Brian_Romska]

Hey Joe! You’re doing great man keep it up! It looks like you’ve got your hands full with all the very technical comments and a decent amount of shade, sorry dude. I’m not smart enough to understand any of that, but I do already have a few pairs of speakers and the WiiM amp and the Apple dongle so I think I’ll give your magic beans a try and see if I have any fun, I bet I will, thanks!!!

[@CMattyMonster]

I ordered two pairs of the Polk XT20 from Amazon UK for £169 when i read the preview of this video on a community post. Got a Wiim Ultra and Fosi V3 monoblocks on preorder. Going to EQ the Polks and compare to my Larsen speakers for fun and giggles. I see a Magic Beans consultation with Joe in my future 😊

[@ryanchappell5962]

Does the Wiim ultra have high pass filter? I know the wiim amp can do that but the ultra is a DAC isn’t it?

[@Stikibits]

toe-in is often overlooked in many set ups, so that'd be something to look at fixing first.

[@joentell]

Agree. I play with the toe-in to get a desired amount of direct sound, side-wall reflection, and cross-talk (sound going to the opposite ear.)

[@nathandaniels4823]

I subscribed because I can see you’ve got good taste in arcade games. 😁 One thing I haven’t seen yet is a meaningful correlation between a certain set of measurements and how enveloping the soundstage is or how well a pair of speakers image, or how much a speaker “disappears”(ie harder to identify location of loudspeaker, only hearing the soundstage) Listening to pro designers like Sandy Gross, I’ve heard of anecdotal evidence that certain build factors (such as baffle width) contribute to better imaging or a wider soundstage. But to date, even asking designers directly, I haven’t heard anyone tell me there’s a way to see that in measurements. This is important to me lately. My own (Jeff Bagby-designed DIY) speakers measure beautifully and in terms of frequency response, compare very favorably to my buddy’s Perlistens. But neither of those speakers can hold a candle to the imaging and soundstage of his much lower end Paradigms. There may be a way to determine this imaging and soundstage capability from measurements, but I haven’t heard anyone talk about it yet.

[@joentell]

You can look at the linearity of the directivity and the polar plots from Erin's Audio Corner to show you how wide the dispersion is. I think the real trick that manufacturers use is a dip around 2kHz which corresponds to the distance between our ears. That's the frequency range we can easily localize by simply moving our head. So, when they scoop that region out i.e. Bowers & Wilkins, then the speakers tend to "disappear." It's also the reason why these Pioneer up-firing Atmos speakers work well because the 2kHz dip makes them difficult to localize directly.

[@NosEL34]

Great video. I definitely feel that the DI isn't discussed or explained as much as it should. 👍👍

[@pristlehk]

Hi Mr Joe, pls try with Elac debut 2 if possible and pls let us know your opinion

[@JoseFerreira-zb7wh]

It would be nice to know some other speakers with this feature, mainly some that are better looking to put in my living room 😀 Any other sugestions? I don't mind paying a bit more, but not as much as the Arendals. Maybe something priced somewhat in between but better looking/ finished compared to the Polks.

[@lukabosnjak3829]

Hope you'll possibly test the upcoming cheap boombox from Earfun (Uboom X) which is being tuned by Oluv's gadgets, conclusion so far is that a cheap Chinese boombox, as long as it doesn't have any flaws in the driver design like this Earfun, can sound nicer than most stereo systems for 10x the price...

[@Albet27]

Yes, Arendal needs a beryllium tweeter for the price they charge.

[@faaldovahkiin3891]

Hey Joe! I'm new to the scene of calibration. I have the polk xt 20s as my surrounds, L&R, but I have the xt15 as a center. I'm using dirac, but I don't know what to set my master volume at when calibrating my speakers. I was wondering if you could help me out with that. I've set my last set of speakers at -17 dB when calibrating them, but these speakers are different.

[@sashinjamir4863]

Joe,can we use a third party subwoofer with the Sony HT-A7000 Soundbar like the SVS/KLIPSCH/MONOLITH/etc...?🙏

[@joentell]

No. Also, an odd video to ask that question since it's not related whatsoever.

[@greenbeginner9221]

What is "Directivity Index"? Please explain for us un-initiated.

[@bpalpha]

Does the THX certification of the Arendals come in to play at all as I've heard THX speakers have to meet certain dispersion criteria? I've always thought those polks are a great entry level speaker. I have a pair of T15s, which are certainly not perfect, but offer incredible performance for the price. Seems inevitable that active or powered speakers in the near future may feature some kind of real time dsp on board.

[@joentell]

I believe the reason why the bass extension on the Arendal Bookshelf speakers is minimized is to pass the THX test for SPL and distortion levels.

[@IliyaOsnovikov]

Joe, very nice video. Thanks! Now, the questions: EQ is great but how important are distortion and compression (output capability) of speakers? Also, would it be enough to fix that upward frequency responce tilt of Polk XT20 with some passive crossover modification?

[@EveryDayJay415]

I don’t t know much about building crossovers but I would guess that hacking a one size fits all mod on a Speaker MIGHT work for a room or two but not for every room, but eq can be custom CURVED for every room. Hits the term room curve. Besides that these mass produced speakers are a sum of their total parts Polk has a budget to make a speaker sound good with a combo of parts, changing stuff around as a weekend warrior might throw everything out of synergy.

[@joentell]

I would be weary of distortion and compression if there was significant boost involved. That's not the case with this. It's mostly cuts in the high frequencies.

[@IliyaOsnovikov]

@@joentell I believe you have mentioned in the video that in comparison to Polk speakers Arendal would excel in low distortion and higher output. Could that difference be easily heard?

[@joentell]

@@IliyaOsnovikov Distortion and compression at the limits of the speaker are easily heard. It's the lower level distortion that might be harder to discern since the SPL of the sound being played goes up with the distortion making it harder to hear. At some point, it reaches a threshold where the distortion is high enough to be audible and is no longer masked by the content.

[@michaelgochez7768]

Joe, although the XT has more bass, do you think the Arendal can probably play louder giving it more dynamic range? Making it better suited for HT?

[@joentell]

I'm confident of that. We used these bookshelf speakers at a recent audio show and we were blasting it at times. The 4 x 10" subs were giving up before these were.

[@MRPC5]

Where i get hung up is with the "rule" that you aren't supposed to eq above the Schroeder frequency, and it seems like all these cheaper speakers with good directivity have boosted treble.

[@hideopalescent]

It's not that complicated. Do NOT eq the response above Schroeder using in-room measurements. If you have anechoic data (or something close to it), you could absolutely eq, but target should be anechoic flat instead of a room target curve.

[@joentell]

The directivity measurements can inform you whether a speaker will take well to EQ above the transition region.

[@joentell]

I would disagree with that statement. An in-room nearfield measurement can be used as it correlates closely with the on-axis anechoic response. Conveniently, it's when it gets to the transition region (what you're referring to as Schroeder frequency) where the room begins to take over and the nearfield measurement becomes unreliable. Luckily, that's the point where an in-room far-field measurement is useful from the standpoint of DSP correction.

[@ChadAV69]

I think the XT20s are pretty good except I wish the vocals had a little more mids to them. They have the highs and bass but that 300-500hz range is missing.

[@joentell]

It seems to handle those frequencies well according to the measurements and my subjective listening to various tracks I know well. Which demo track sounded like it was lacking in the mids? I'll listen again.

[@ChadAV69]

@@joentell Just in general. I can hear it on all the track demos. The Arendal is a lot more forward with the lower mids. It's also less lispy in the highs than the XT20s. The XT20 is a good speaker but those two things I don't like about it. Still good for the price.

[@jamesdiaz6844]

Great video, a lot of detailed information. But that’s a lot of work to get avg speakers to sound great. I’ll stick with my micca rb42

[@joentell]

It's actually not much work if you're familiar with DSP. With the WiiM Amp, it's just about entering numbers into their app. It would take 5 minutes. I've demonstrated RB42's at an audio show for fun and have reviewed them. They have impressive bass for their size, but these XT20's are superior in various ways. The RB42 has a pretty solid build and looks cool IMO.

[@greenbeginner9221]

​@@joentellwhat's the cheapest I can go for "calibration"?

[@joentell]

@@greenbeginner9221 I think I've mentioned it in this video specifically. Polk Xt20 and WiiM amp

[@greenbeginner9221]

​@@joentellany suggestions if a guy already has an amp and speakers?

[@joentell]

@@greenbeginner9221 see if you can find the speakers on Spinorama.org and see if the directivity is good. How well they EQ depends on that.

[@josealicea8691]

Hi Joe is there a way to use the magic bean with an Anthem 70 and if you can’t how could I go around it without replacing my pre pro … lol :)

[@joentell]

Maybe a MiniDSP DDRC88A between the Anthem and your power amps?

[@srtswpak47]

Isn't the 1723 high passed by design? It lacks in bass and is designed to be used with subs. What SPL could the Polks play at?

[@joentell]

It seems like it is built that way on purpose. Not sure about the Polk SPL. Loud enough for me in my room running full-range.

[@crazydwarfer]

Hey, what would be your recommendation for the least expensive speakers that, with a help of magic beans EQ and calibration can reach THX levels at minimum distortion in a 22x16 room? Speakers will be used for a base layer in 7.1.6 HT setup. Dedicated home theater with sound isolation and acoustic treatment as per Anthony Grimani guidelines. Thank you for the answer in advance.

[@joentell]

Which THX certification is that? There are several

[@Echo-jg8is]

22ft by 16ft will be 3520 cubic feet based on a 10 ft ceiling, that means you need to reach somewhere between THX ultra to THX Dominus status, good luck. 😬😬😬

[@StephenMcGregor1986]

@@Echo-jg8is yeah Perlisten and they aren't "cheap"

[@joentell]

I would guess some of the Arendal or Monolith THX stuff.

[@chinmeysway]

w your sound demos it’s not really working to compare the two speakers bc of switching to the original track in between them.

[@joentell]

It's more about comparing each speaker to the reference track. So, it's an indirect comparison.

[@ManCaveAudio]

Is there any discount on True Target Pro?

[@joentell]

Stay tuned!

[@user-zo9xw6pt8i]

So polk xr20 vs Monolith by Monoprice THX Certified Satellite Speakers?

[@joentell]

Polks are larger which means they can play louder and have more bass extension. The Monolith compact satellite are good for small rooms, at a desk, or as height speakers.

[@user-zo9xw6pt8i]

I am in a small room 13×9 8ft ceilings. The main listing position is at the far wall (bedroom), but I do want to use all the same speakers. 70% movies and tv, 20% xbox series x ,and 10% music. My concern is the 13 ft vewing distance with the monoprices' low sensitivity for the front set, but the polk are rear ported, so they need to be away from the wall. I plan to use dirac and magic beans. Should I mix and match? Keep looking for a different speaker? Just use one of these? Jtr and ascendo speakers seem the closest but $$$$$. Lol What is your opinion?

[@joentell]

@@user-zo9xw6pt8i maybe use the Polks for the main speakers and Monolith for height. I assume you will use a sub

[@ManCaveAudio]

Where is bass in Arendal?

[@joentell]

That's what I said in my initial review. I think they're going for high SPL when these are used with a sub.

[@Bradimus1]

This is reminding me I want to replace my height speakers, but probably not with these as the port isn't ideal.

[@joentell]

I like the Monolith THX Compact Satellites for height duty depending on the room size.

[@Bradimus1]

@@joentell it's something like 15 x 30 with an 8ft ceiling but it's all crammed over on one side because the prior owners had no idea what they were doing. 😂 It's all prewired and 120" projector screen or I would have considered changing things. Those are an option to consider on a list of a few I have to look at on prime day.

[@joentell]

@@Bradimus1 I'm a fan of concentric speakers for heights because you will surely have reflections from the nearby wall or ceiling.

[@Bradimus1]

@@joentell I agree, but those are pretty output limited and don't dig very low.I think I would prefer to use those as desktop speakers or bedroom home theater. Mostly given I like to do all channels stereo for music often enough - and loud!

[@Bradimus1]

The KEF Q50a would be great, but more than I intend to spend on those. But some of the nicer Polks may go on a big sale.

[@simpsonbergman2185]

Wiim pro stremer also has peq in the app. So you don't need the Wiim amp do peq if you have the streamer, right?

[@joentell]

Correct. The advantage of the WiiM Amp is it has sub out with delays for the main speakers.

[@eddietours3728]

The Polk sound a little thin to me 🤔

[@joentell]

Thinner than the Arendal without EQ? What is your definition of "thin" sound? Also, what are you listening on?

[@eddietours3728]

@@joentell hi Joe I use headphones, the Arendal sound a little warmer more weight maybe is me lol

[@joentell]

@@eddietours3728 which headphones? I find it interesting because it's the opposite for me. Which demo track do you hear it most on? I'll listen again.

[@eddietours3728]

@@joentellthe focal bathys demo 2

[@joentell]

@@eddietours3728 I figured. I keep the original track for reference. I think the issue with that demo is it's only playing the content for the left speaker. I think the way they mastered it, they split the voice and reverb between left and right channels, so it sounds weird with just one.

[@ryanchappell5962]

If you have a mini DSP 2X4, you can bypass the crossover and just about any speaker and drastically improved the directivity index. You’ll also get rid of all the nastiness from the low parts quality, practically all speakers have. You would lower distortion by being able to use a higher order crossover, which also improves the directivity index because there is far less overlap in the drivers which is where most of your issues come from regarding directivity index. I don’t know why more people are not doing this, it’s very easy to run speaker wires straight through the port and you don’t have to damage anything inside the speaker, just unhook the terminals from the drivers and then connect your wires directly to the bare drivers and then use the mini DSP to do all crossover functions. If you ever want to go back to the internal passive crossover, you can do that!

[@jamesbrotherton5487]

My wife always likes the cheaper gear too!🙂

[@CensorMeNot-dv5lg]

I really try not to like Arendal because their ads are SSSOOOOOOO LAAAAAME... Pasted all over over facebook sayin' crap like our speakers sound like they could be president... or a sound that rolls across a western plain.... (not exactly) but there was never a real spec or piece of hardware or number they would show. Alas... I saw them at a friends, and they sound great! For example, my sweet sounding budget Fluance speakers don't handle heavy power with such confidence. Only hearing both in one day would deliver such an observation. I'd still spend the money on Fluance.

[@supamanithan1492]

How your app is different from Dirac Live Room Correction?

[@joentell]

It finds the correct target curves, instead of recommending generic ones.

[@michaelwyckoff7593]

Yo Joe😊

[@celstark]

Omg! The WiiM units got 10 band PEQ!!

[@amanieux]

don't you think that sound reproduction is complex and that a single type of measurement can not encapsulate all this complexity, but our ears do grab all this complexity hence the lack of correlation between "sounding good" and "measuring well"

[@joentell]

I think sound reproduction and how humans experience sound is well understood. Many have dedicated their lives to researching these topics and the information is out there for everyone to learn. I'm trying to condense the information in ways that is easy for people to understand. The first step is letting go of the myth that we don't understand psychoacoustics and why there's such a thing as objectively better sound reproduction which can be measured and observed. The measurements also correlate with blind listening tests. Also, directivity is derived from an on-axis measurement and either early reflections or a sound power measurement that requires many measurements around a speaker. So the directivity index measurement actually has a lot of information in it.

[@RennieAsh]

A single type of measurement doesn't encapsulate everything - that's why we have lots of types of measurements. Directivity is a significant factor however if you're after accurate sound and ability to use EQ effectively . That's the aim of the video

[@joentell]

@@RennieAsh As you already know, an impulse response sweep can tell you a lot more than just on-axis response.

[@daleboylen6427]

Joe, that mic cannot distinguish between floor bounce and direct sound off the woofer, nor splash off the tweeters cabinet or direct sound, so how can it "Correct" anything? Also, one mic, two ears. Microphones condense 3 dimensions into one: distance, which is time. Recording engineer here. The issue with 99% of speakers is crossover induced phase shifts or time delay. Adding EQ simply INCREASES phase shifts. The ONLY way to avoid this is by using a simple 1st order crossover. The output of a crossover network is a vector sum with real and imaginary components in polar coordinates. What you have in a 1st order at the crossover freq is one vector at .707, +45, and the other at .707, -45, which adds to unity in vector space with a combined phase shift of zero. But because the vectors rotate together with frequency, they are always 90 degrees apart, and they always add to unity voltage and zero phase in vector space, no matter what the frequency. You cannot EQ it out. You can not DSP it out unless your dsp unit can alter in real time varying time delays at each and every frequency as you move away from the crossover points. Haven't seen one yet. When a time-coherent speaker’s sound reflects from very-close-by, acoustically-untreated hard surfaces, these reflections are then clearly audible as distinct reflections, especially in the voice range and low treble, because that is how we hear (Haas effect). In the bass, such strong and early reflections produce the standing waves that all audio books predict, made louder and more numerous by this small sealed room’s rigidity and therefore its lack of damping in the bass. Numerous means that the speakers can then sound warm in this room. When a non-time coherent speaker’s sound reflects from very-close-by, acoustically-untreated hard surfaces, these reflections are then less audible as distinct reflections, since they are scrambled in time, therefore sounding more diffuse in the voice range and low treble, precisely the region in which those speakers have the most time-smear. These statements are facts. Polks, in my experience (used to sell them) use 2nd order crossovers. One of the basic facts about second-order crossovers is that they require at least one of the drivers to operate in inverted electrical phase, to avoid a null in frequency response at the crossover frequency. This inversion alone is enough to utterly destroy the integrity of the musical signal. No one in their right mind would use second-order networks in the first place. It is not possible to fix the inherent phase problems in a second-order crossover, because they are frequency-dependent. This is simply a mathematical absolute, at least in the analog domain. And phase inversion of one driver is a Really Bad Thing, no matter what the reason for it, because it completely screws up the original signal. Nowhere in the recording chain, nor in the playback chain is the timing split between highs and lows, or the polarity, or both. This is purely a speaker phenomenon/distortion. One can learn to recognize that, the way an amplifier designer can hear if someone's amplifier needs a bigger transformer- it's a unique sound distortion. With high order crossovers, the first energy to arrive from that step-input is upwards-going, as it should be. A moment later, the late-arriving, inverted-polarity tweeter shoves (sucks) that initial positive air-pressure-increase down into the negative-air-pressure portion of the graph. The tweeter's dome then returns to rest from its full "-" excursion, because the crossover cannot pass the "DC" to tell it to "hold your position, albeit sucked in". The air pressure then returns to the positive from the midrange tones' positive-pressure continuing to arrive. Not sure how magic beans or EQ or DSP can "fix" that. As far as speaker measurements go, which ones are you looking at? When measuring a speaker, we assign 0 degrees at the moment its first sound arrives at the mic. Most always, this is will be at a high frequency coming from its tweeter, before that tweeter goes into a breakup mode, at 10kHz or higher in a modern design. Now, as we go down the scale looking for when each lower tone arrives, most every speaker lets those lower tones drift backwards in time more and more the lower down we go. If it does this smoothly, that is linear phase. If it does not drift backwards at all, that is time-coherent behavior. Let the starting phase be set to 0 degrees up at 10kHz.Down at 7kHz, our software measures the phase as ’60 degrees Positive’.This tells us three things: 1. The time delay at 7kHz is 60/360, one sixth, of the 360-degree period of a 7kHz cycle = 1/6 x 1/7000 second = 0.023msec. In space, this is equivalent to ~8mm behind the location of the 10kHz location. (0.023msec x 0.340meters/msec speed of sound). You could say ’it sounds like and measures like’ 7khz source is 8mm behind 10kHz source. 2. ’Positive degrees’ means ’time delay’, because of how the (unseen) math equation was set up. 3. On the ’scope, a 7kHz pulse (a ’beep’) of sinewaves from the tweeter moved to the left by 1/6 of a 7kHz wave cycle. It started late by that amount and thus ends late by that same amount. Now, down at 3.5kHz, one octave lower, if the phase change is 120 degrees total (of 3.5kHz), then we say the rate of phase change is ’linear with frequency’ and ’60 degrees per octave’ if we like. Such a speaker is linear-phase, because its designer has also taken into account the mechanical phase shifts of its drivers. Its rate of Phase Change is SMOOTH, not ’jerky’ (= ’non-linear’), which leads to a ’smooth transition between drivers’ as Stereophile’s John Atkinson writes. Time coherence is a much tougher performance standard for speakers. It is possible, by the way, to correct or offset most all of the mechanical delay in the drivers. When a speaker distorts in the time domain, this blurs imaging and details, and more important if one’s ears are open to it, ’how’ the music is being played and its emotional content. Good design, based upon physics, not DSP and/or EQ is what is needed. Hard to find in a speaker today at ANY price. Let alone $250.00/pair. YMMV.

[@joentell]

There's too much in your comment for me to address one by one, so I'll address the most important ones. You stated that a single mic measurement cannot distinguish between direct and reflected sounds. That is true which is why we take measurements in the direct dominant field and the reverberant field to see the differences. You talked in various ways about the phase shifts caused by either the room or crossover. There are ways to linearize those shifts using FIR filters and all-pass filters which software like Dirac can do. Dr. Floyd Toole mentioned in his book, which I assume you've read, that the absolute phase of a single speaker and shifts caused by a crossover are difficult to detect. I have experimented with this myself using an all-pass filter to rotate the phase in real-time. What we do notice are phase relationships between speakers which is why linearizing the phase can help with coherence.

[@daleboylen6427]

​@@joentell You have MUCH to learn. I never said a word about phase shifts caused by the room. it is a speakers crossover issue compounded by EQ Absolute phase of a SINGLE speaker would be hard to detect. Other than cone breakup, there is no phase shift. I sat for 4 hours a day, 6 days a week, for 25 years designing speakers. Change a capacitor, inductor, resistor, crossover point, what do you hear? We tried every single conceivable crossover topology. Every single configuration. Sealed, ported, transmission line, ribbons, all of them. We measured them all using the finest drivers, using MLSSA. The difference between a time coherent speaker and one that isn't is not small. Every single person who took the time to sit and listen easily heard the difference. It's not about directivity, but feel free to chase that ghost and beat that dead horse. Again, I suppose it is theoretically possible to correct crossover induced time delays using DSP, but why not just properly design the fucking speakers in the first place and avoid additional electronics in the signal path? Because to do so you would need a degree in advanced physics. Or know greens functions. I can only think of two speaker designers that fit that bill. Neither were named Toole. I've been in audio for almost 50 years. In those 50 years I've had many times where I thought I knew it all. I did not. So, I sat and read technical white paper after technical white paper all the way back to the 1950's. In fact, it was a 50s RCA paper that we used to break the time domain math, which took 30 years as a physicist to do. I'm sure YOU are far more capable than we were/are Joe. Polk audio huh? Cute. Sold them all, dating back to the 4's 5 jr's, 7's 10's 12's, the SDA's. If I had a dollar for every one of those peerless tweeters I replaced, I'd be rich.

[@joentell]

@@daleboylen6427 I know your type. Go ahead and unsubscribe. I get the feeling you like to think you know it all. Trying to impress people with terminology. I'm not impressed. People who really know try their best to make things simple, unlike you. I hate people who talk down on others. If you want to debate the topic, then do that. I don't care if you've done this for 50 years. you can still be wrong. Just go to any audiophile trade show and many of them have been at it for that long also. It means nothing.

[@daleboylen6427]

@@joentell Never was subscribed dude. Just correcting you because, and I know this is hard to believe, but YOU ARE WRONG.

[@joentell]

@@daleboylen6427 Thanks for your amazing wisdom. You've taught me stuff about audio I've never heard in my life. All very relevant to the topic of this video. NOT!