How to NOT Mount a Tweeter or Woofer in a Baffle 

One of the great joys in life is surfing through the Parts Express catalogue!

I recently started training Brazilian Jiu-Jitsu and as a new white belt, I am often told what I should and shouldn’t be doing. One thing I hear more than most is that I should only focus on defense and leave submissions for a later in my training. After rolling with an upper belt and failing to catch him in a submission, I asked him what he thought of the “only focus on defense” suggestion. He told me “Though that is technically proper advice, submissions are too much fun not to try, even if done improperly by a white belt. And if having fun keeps you coming back to learn more, keep going for those submissions and learn as much as you can in your failure.“ I think some people strive to make DIY speakers with the most accurate sound reproduction and some people just want to make cool shit that sounds pretty good. I'm a big fan your videos and am so glad you share your knowledge with all of us!

On-Axis vs Off-Axis Angle measurement would be also very interesting. thanks for great video anyways.

Is highly surprising for me the lack of good information about how to design and build loudspeakers and crossovers. I think you one of the very few who give us good science based info about. Thanks and regards

Great work and video! There is nothing better than experimenting with different designs to see what works in reality. Sometimes we rely too much on what other people have said and by doing so we can make mistakes which will be detrimental to the overall sound of a speaker. You applied a real scientific method and teach us not to take things for granted. Thank you!

Good video. Your second fixture functions as a miniature horn loaded tweeter. That is why frequencies below 7Khz got boosted. The angle of cut in your baffle decides which frequency range to boost/cut. Instead of 45 degrees try an angle of 18 degrees. Frequencies above 7Khz will get boosted and it will sound better and cleaner than flush mounting. But this quality comes with a price. The output becomes more directional and you just cannot enjoy it all over the room like you can with flush mounts.

Really cool that you have measured all these drivers and made it public.

Very interesting to see such frequency response comparison. Good job!!

Keep up the good work. Thanks for the content

Loved this video too, and I don't ever think that information is "negative." People gotta learn somewhere!! I was surprised also about how close the responses were. Another option for these DIYers would be to do exactly what you did in the video, and design themselves a crossover around the measurement they take with their tweeters loaded this way, if they're actually taking measurements that is... Great video, also loved the Xsim video I saw as well!!

With a flush mount that tweeter had +/- 2 dB (or less) from 3 to 20 kHz. And in that chamfered hole it's more like +/- 5 dB. That's quite a difference!

Thanks for sharing this. I have seen this kind of tweeter mounting way too often now by unexperienced speaker builders but also by people that at the surface appear to have some understanding of diy audio. I am still suprised how well that tweeter measured on-axis with the rear mount although I expect it to be a different story off-axis.

7:30 I am so glad you did this. I have been wondering about this trend in back-mounted tweeters which look pretty but produce a hump in the bottom and delineate at the top, and your tests show this perfectly. I would also be very curious what the off-axis response is. We would assume the rear-mounted tweeter would have big rolloff, off-axis. But we have to remember: such a thing could now be desirable, as we all live in increasingly small living spaces. So front-mount for a bigger room, rear-mount for a smaller room. And that's why I think these designs, both of them, persist. There's also one other mode of tweeter mount worth mentioning: the ghetto shed life "affix it to the front of the speaker, and run silicone rubber as a gasket" with a woofer mounted the same way. It's expectedly forward-sounding and is great for older folks who have reduced treble discernment. But if you want it to sound better for most people, the trick to that is you just find a low sensitivity tweeter and pair it with a woofer of higher sensitivity. Say, a tweeter of 87 and a woofer of 89. That's if you front-mount them, simply find a quieter tweeter, even if it's 1 dB difference. I say that because I'm terrified of resistors.

This is exactly the information I was looking for. Thank you.

Just a suggestion-- probably a lot of people, who are just starting to learn about speaker design, might not know what a "Zedma" file is. Many times terms are thrown out there at high speed leaving the listener saying to themselves - "what was that? a what file? what's he talking about?" Why not just say an impedance measurement file? I couldn't tell you how many times when I'm trying to learn something new, the presenter uses some cryptic term, usually pronounced so fast I have to replay the video over and over trying to strain to understand what that one critical term was. However, I thank you very much for helping others trying to learn this craft that does involve a lot of technicalities.

Very good information base on the actual test tq

Great video mate!!!

Great video, really clear that the rear baffle mounting will disrupt frequency response, and also may disrupt frequency distribution. You would say the rear mounted tweeter has been slightly horn loaded, resulting in the slight amplitude boost. It should be pointed out that most drivers are designed for front mounting. I usually mount the driver directly onto the front baffle, whereas most folks correctly flush mount them, avoiding that small step from the driver face plate to the baffle. If this small step makes a difference, then rear mounting would be much worse.

I have found your channel relatively recently and am really enjoying your videos, could you do another video like this comparing flush mounted to flat mounting? I know its a good idea to flush mount drivers, but id love to see measurements comparing them

Great useful video as always.

That was interesting! Cool comparison and explanation.

I was sure that with baffle it will sound better, thank you for this video!

As always best audio chanel in youtube, keep the good content man. By the way have you ever worked with TYMPHANY NE123W? Im planning to use them as a dedicated midrange for a 3 way, if you can make a review of them would be great.

Cosmetic sound VS serious music... You all know where I stand on this. Some of the crap I see today is really ignorant and stupid.. THANK you for doing this test and video. Expose the frauds and the stupid for what they are.

Thanks for the info! I have a tweeter here that has no Frontplatte to it and its pretty linear and after seeing that I don't think that i will not make some kind of short waveguide for it. But i will still make some and test them and see if it give's me any benefit.

Realy god Job. . And nice work Room🙂

I definitely understand the loading effect of the chamfer but many times this approach is used to protect the drivers,keeping them below the flush line of the cabinet/box. A shallower piece of mdf and rounding all edges would've likely decreased the effect as well. Great piece of information,thanks for sharing your knowledge.

These lensed baffles would tend to make the output of the drivers used very directional. Professional speakers use wave guides for huge venues that cover a large area, and often the speakers are arrayed to provide even coverage. My custom built Focal two ways use flush mounted tweeters that have the top portion of the cabinet cut away like a diamond. This allows the tweet to diffract sound. When I heard the prototypes for my speakers through a high end pair of tube amps I could walk directly between them and not tell where the tweeters were with my eyes closed. Great demo. With my Denon solid state amp things are more directional, but realistically when sitting in my living room listening to music while sitting near the sweet spot it doesn't matter one bit!

Nice work!

I like your approach and your MTB. What about directivity with/without Waveguide ?

I would like to add that the format and the way Kirby produces his video's make it way more interesting for me to dive in the exciting world of diy audio! He is very focused on results and builds cool stuff that would avoid newcomers to be hit with a serieus case of paralysis by analysis... If I am sometimes looking at these videos made by experts with there thou should's and the immense amount of variables that should be considered, a bit of joy is lost. On the other hand, if in the future my 4th project came to an end, I might be looking for more information in detail and understanding of all the variables. Then I know I propably should be looking somewhere else! The content just serves different causes and is focussed towards different people! My first build will definitely contain a counter sinked baffle design, just because it looks so cool... I can thank a certain RU-vidr for the excitement his videos brought upon this great world if diy audio!

Amazing video!

I really like your videos, so many to check :) Does dayton have some valid high end drivers in class of scanspeak, dynaudio or morel? Are they good drivers to work with? One more thing, do you have some good idea about gasket material for sealing drivers but not adhesive one. These sticky sealants are nightmare to remove drivers later especially when flush mount. One more thing, do you prefer Xsim over jeff bagby xover designer spread sheet? Cheers man and keep up with good work

i'd like to see the frequency measurements on both 0, 30 and 60 degrees angle. I'd expect these measurements to show even better, why you should not mount the tweeter on the back.

I've been thinking. Can I increase volume level when I installed a flare in front baffle of my bass reflex full range tower speakers? I want a more directed sound in my home theater system. So that all the sound energy directed to the seating area

I would love to see a different analysis: the same tweeter but with a 60º chanfer, since in high frequencies the wave lengh is actually smaller, so maybe with the 60º chanfer the results should be different. On the other hand, for a woofer, the low frequencies gives extra long wave lengh, so my question is, will it affect a woofer the same as the tweeter?

I have a question about installing boom mat baffling in vehicle around the 4ohm flat mounted speakers, (4, 300w 2-way kenwoods 6-1/2, 16gauge wiring) wondering if I should or shouldn't? Also 2, 6×8 in rear deck with a custom drop in center shelf box 12" kenwood sub, 14gauge wiring. Would this clean any distortion or do I need to add another amp, 2ch. Mono block obviously for the sub lows? Or should I just reconfigure the low/high gain levels on the 800w kenwood 4ch. amp that has internal & 4" external fan & led mood lights i added to the circuitry thts driving the 2-way mids which also has the tweeters on the inside? No soundproofing anywhere else except for the floorboards ive recently insulated with heatshielding, custom rubber rhino liner done which did help with tire/wind/road noise. I want the sound controlled, 8"Bluetooth head monitor system, linked to keyless Wi-Fi enabled detection alarm system, 3 motionsensor spot lighting/ IR cameras w/audio, onboard Wi-Fi, with talk back. 3ch.mixer PA system. I like the sound quality & clarity from my CTS sport, on board Wi-Fi 40gig drive, Bose system which im pretty sure has been designed specifically for tht awesome sound with a few more 8ohm speakers in areas in not fimilar with. I havent maxed out the peak amperage of the amplifier jus in case anyone responds. All electrical wiring has been upgraded to oxygen free 2/4gauge copper on all leads/grounds, gold plated terminals 2gauge, 220 watt alternator paired to 24v system for all accesory equipment, my traffic strobes, spots, flood road safety lights on 12/14gauge wiring. I want solar added next to the invertor system so I can be ready 4 anything, but all tht interference/resistance coming from any wireless connectivity needs to be solved 1st b4 introducing any new devices. Dvds/cds/ aux /USB/boost gauge, tuner hard line in/out works without noisy interference. How do I clean up the wireless interferance mess? Bluetooth/camera/Wi-Fi seems to be the issue, creating some kind of electrical field/wave sinking & distorting the connection which is wireless SMDH Sofar this vehicle powered an entire house for 5 days & only used lil over half tank of gas when the power was out & thts b4 the dual batt upgrade. It's a purpose built work horse vehicle tht has fooled plenty who thought it was a slow stock vic tht still returns great gas mileage on longhauls with no check light, 4cats & muffler still keeping tht incredible 5.0 roar suppressed from all but inside the cab which barks even under the slightest throttle input, 3.75 yukon gearing, steel reinforced 8.8 locking rear dif, stage 2 severe duty suspension, all aluminum driveshaft keeps the goodyears from breaking loose & making use of tht torque for pulling heavy trailer loads without searching for gears or trying to downshift on curve The sct sport tune compared to the trucks all around high expense & can safely haul 24ft" trailer with T-sway & brake controller used & the truck as the load. Twin intake stealthily hid behind grill w/wide rears 2" offset is the only giveaway P.s. Plus 1, 12" sub & dyno mat the entire vehicle for tht crispy clean & clear, undistorted sound?

What about tweeter placement on the baffle? As in what distance to place it from the sides and top? Centered or offset? Is there a video on this? I'm curious what effect this has on the tweeters response. Thanks.

As nice as they look, I hate LIFESTYLE speakers. The sound is compromised for appearance, thus defeating the purpose of a speaker for me.

Great video! Maybe do another video showing a curved/beveled baffle versus a regular flat face with square edges?

This is exactly what I would have expected. First of all I would round over the edge so it meets the baffle plane in a smoother fashion. The extra efficiency is always worth it because you don't heat the coil as much, and you can lift the output above 7kHz with an R in parallel with a C. Rounding off the inner edge at the throat of the chamfer would also help too. Personally I think it is an excellent idea as it controls the directivity to match more what the midbass will be doing at crossover and it puts the tweeter in a plane closer to the source of the midbass. I really don't know why you aren't recommending it.

Thanks man! I always knew this was not ideal. Now I have some real data to back it up! Makes me wonder how smaller woofers behave in the same setup... Think it would be the same kind of result (waveguide loading in the lower end of the frequency response with a dip at the higher end? I'm specifically thinking of that ND series of aluminum cone midwoofers from Parts Express. I think the cone is slick looking, but I can't stand the odd style mounting frame. They even just released matching passive radiators which are appealing, but not if I can't get good sound while still hiding that mess of a mounting flange!

Great videos. one point - Diffraction audibility is worse than FR might suggest. Recessed tweeters, horns and waveguides etc, all have an audible noise floor, hence, a coloring effect and/or masking of recorded detail...

Then you for doing this. It drives me nuts every time I see someone blindly loading their tweeters this way. A certain RU-vidr does it all the time. I think the off axis responses would be even more of a mess, even more so in the time domain where it'll smear like mad. Think being the word, I have no measurement kit past a umik.

Great job

I love for what you did for us

I wonder if the measurements would drastically change off centre?

Conclusion: it is better to do Flush /level (AHF will be like in the datasheet), and the type in the horn can be done if you need to raise the midrange and medium-high with a decrease in the treble Вывод: лучше делать Заподлицо /вровень (АХЧ будет как в даташите), а типа в рупорке можно делать, если надо поднять СЧ и средневысокие со снижением ВЧ

Truth has been spoken. period.

Excellent as always.. What would be the effect of rear mounting a midbass / woofer? Will it have a similar effect as the tweeter?

i heard Klipsch LaScala mid/tweet horns use a 7" aluminum driver or something like that. How do they get THAT to sound great through a huge horn lens?

I plan to build an open baffle speaker using MDF or HDF but I can't get the thickness I want (1.5 inches to 3 inches) in any local stores. Is it a good idea to just glue sheets together?

it would be awesome to teach us how to design a good waveguide

If you'd like to discuss, i wonder how it could be important to work on the inside of a really thick baffle for a mid/bass driver ... assume a 3cm front plate ... so at least a cm inwards, the opening starts to decline at 45 degrees outwards (or so) ... Wouldnt it help in some way? If ure interested ... I plan to use some dayton rs225 on a 3 cm thick baffle ... massive birch wood I want to have a really sturdy construction ... even plan to do a 3 way MTM design with Founteks NeoX2.0, daytons RS52AN-8, and mentioned RS225-4*2 Got some nearfield purpose here on sight. thought this would be a fruitfull solution :-)

the loss in the upper is, as you stated.. down to the diffraction where the outer edge of the conical depression changes angle to the flat plane of the baffle and possibly from the junction between the wood and the bessel. i'd be extremely interested to see a plot of it again with that outer lip rounded over at the angle change. you'll still have the falling response but i think you can get rid of the upper dip. i saw you got a pretty good fit to the curve of the tweeter bessel but i wonder if you could get it closer with some filler to create a completely smooth transition from tweeter bessel to wood flare? much love xx

I wonder whether a roundover would be better for a tweeter than chamfering as, at those frequencies, the transition to the baffle is going to be pretty important for reflections/diffraction (kinda like how the mouth termination is for a horn).

Please correct me if I am wrong, the chamfer is loading the tweeter like a small waveguide and that loading is too much on the diaphragm and the motor strength so that's why it's lowered the efficiency on the top end? So, in theory, would this happen to a 1" compression driver on a horn that is too large ? I see these old timers with 1" Altec 802 drivers on 1.5" Altec 311 horns with adapters the horns are 30" wide 12" tall at the mouth and 21" deep and they never have high's. But these same drivers on smaller horns have decent highs.

Another thing even high end companies really mess up. A port. I listened to $38,000 a pair JM labs speakers with a front port. The port was arc-shaped. Every piece of music was badly colored by the port. That is a very undesirable, mid-fi sound. Had they engineered the port, it would be down or rear firing and properly shaped.

Nice video, you could have also done various off axis measurements, this is where a lot of diffraction artefacts would have potentially been more visible. 😊

can that dayton tweeter replace the one in the micca mb42x?

Would the chamfer baffle matter if it's used in a subwoofer application?

What directivity measurements, 0,30deg, 45 deg etc..? the idea is that the rear mounted tweeter has better directivity perf. in this case?

So a chamfer for a midbass driver (up to 1300Hz XO cutoff or so) is not a good idea too??

🤔🧐 ..GREAT EXPERIMENT!! ..NOW, I’M CURIOUS TO KNOW HOW THAT SAME GRAPH WOULD SHOW WITH THE TWEETER MOUNTED JUST A TAD BIT ‘FORWARD’ RELATIVE TO THE BAFFLE (CLOSER TO A SURFACE MOUNT)..

How do you measure the response ? Thank you much!

could you explain why speakers like Klipsch LaScala use horn mid/tweet drivers to cover most of the audio spectrum and they sound amazing apparently? and a horn loaded woofer as well. can you explain why these cost tens of thousands for their signature sound when 15$ tweeters start sounding worse when mounted behind a little bit of a chamfer?

Does anyone know if the chamfer acts the same way for a woofer? The tweeter got a DB increase on the bass region, if it does the same on the woofer, than it might actually be something that some people would want to do on their speakers in order to increase bass. I know he said that you shouldn't mount a woofer this way, so I'm not sure if there is some significant negative effect on the woofer like the sharp transition on the tweeter I'm not thinking of, I'm kind of new to speaker building.

What MC are u using? And program?

What about midrange?

Do not know about the tweeter but it is a great idea for bass units. The reason be that if you build with a solid stiff baffle, it is usually thick. So the bass units will have less air contact if it is mounted on front of the baffle. Waaay better behind the baffle due to you do want a restrain less cone without compression and ressonance towards the baffle. It have no real meaning in the lower spectrum of the frequencies. But you do not some kind of compression towards the baffle.

Has that top end energy gone off axis? I wouldn't expect it to be destroyed by defraction.

What is the difference, if any, for mounting the driver onto the face of the baffle without flush mounting (so driver edge sticks out a few mm). Great videos by the way

I fully understand the problem with back mount baffle design like this, but what if you did a hybrid? The aesthetics of a chamffer is really nice... What if you did a double mdf thickness baffle and mounted the tweeter to the front of the back peice and then did a thin chamfer on the front peice? Best of both worlds?

The big reason for doing something like a rear mount is for better time alignment with midwoofer or midrange at the desired crossover frequency. I would think with a more gradual wave guide that you can get the best of both worlds. The way that's depicted in the video is absolutely the wrong way to rear mount a tweeter and if diy speaker builders are doing this for a fashion statement alone then they should just stay away from speaker building altogether. I cannot tell you how many times i've seen real manufacturers build speakers with a recessed tweeter speaker next to the midwoofers with a huge square 1 inch 90 degree lip a few inches away from the tweeter for time alignment. so much for a smooth crossover between the mid and high frequencies.

What about full-range drivers??

This is maybe not 100% related but what about distance between drivers? How much and why? Does it differ depending on the crossover frequency?

There must be some benefit, no? I was looking at the beolab 90, the mid-woofers and tweeters are capped with a chamfered edge baffle. However the woofers are not, and the whole speaker is hidden behind a mesh/grill anyway. Can it be used intentionally to boost the low-end if the drivers they use are quality enough to compensate with DSP? Thanks! great video

I actually thought some back mount their tweeters to kinda time align it with the woofer.

Surely off-axis will be where it really shows?

What about this micro horn effect in woofers? I often see this in klipsch cornscala builds

Is this true for all speakers or just tweeters or just certain tweeters?

​doing db drags across the midwest!!!

It didn’t “lose dB” on the top end, it likely moved it off axis due to the waveguide.

Are you by chance from anywhere around Alberta?

I'm assuming this holds true for midrange, woofers and subs as well?

Does this apply to a woofer also?

Like you said, although the chamfered look is kind of cool, you lose clarity none the less. Let me ask you a question or two. 1) What are your opinions on speaker grills? Specifically the steel mesh ones? Do things change by the type of metal used?(brass, copper, aluminium, steel) 2) When installing a passive radiator, does having it face in the front or in the back have a bearing? I know you can add/remove weights to determine the tone. I'm going to build a small bluetooth kit from Epoxy Resin, And just wanted some insight.Will be a 50x50x100 setup (might not ever need the subwoofer.) with 2 Dayton Audio 65's and a passive radiator to start with.

Off axis tests may have shown a worse outcome with the chamfered baffle

Is this the same for a sub ?

Some drivers are suitable for rear mounting, some are not. This one is clearly not, as it already comes with a waveguide, however, with a matched baffle, for example Dayton Reference series drivers can be used for rear mounting and a driver like ND25FN is designed to be rear mounted.

i think off axis measurements would have shown greater deviation VS onax measurements.

I sink mine in auto carpet ,short napp. Woofers flush and carpet. Lot of designs ,have fun.

Magico?

*_Yep! Its called 'Time Alined'_* 👀🥴 *_...By the way, Dayton Audio has specifically designed this tweeter with this exponential horn-loaded waveguide for a reason._* 😏

Single measurement isn't going to cut it. What about off axis?

the normal way AKA the right way.

I'm pretty sure the off-axis measurements would be off the roof.

What about woofers?

I don't want to sound dismissive of tiny differences as audiophiles live on fixing those. I will ask one question though, I'm designing a speaker as we speak, and a shallow recess is fine. Not the Mariana Trench you've created here, I'm talking millimetres, to be able to put a protective mesh over it or just so the grille is far from it.

I think -20 dB difference could be considered as a "bad result'