Hello everyone.
I've been lurking on these forums for years. Currently in the process of designing no-compromise studio monitor system. It will be a 4-way looking something like this:
20-60Hz - 15" woofer (still deciding on the woofer)
60-600Hz TAD TL-1601b
600Hz - 8,000Hz TAD TD-4001
8,000Hz and up - RAAL ribbon
Looking for the best horn to make the most of the TD-4001 in those frequency ranges. Was recommended the Yuichi A-290, and can also get the TH-4001 clones made. Looking for the most transparent setup, and it will be driven with a high quality Linea Research DSP (gasp) and Benchmark / Bryston amps, so we have a lot of tools at our disposal, such as time alignment, FIR, linear phase EQ, etc.
Are there any other horn designs we should be looking at for this? Anything we may have overlooked?
Your help is much appreciated.
I've been lurking on these forums for years. Currently in the process of designing no-compromise studio monitor system. It will be a 4-way looking something like this:
20-60Hz - 15" woofer (still deciding on the woofer)
60-600Hz TAD TL-1601b
600Hz - 8,000Hz TAD TD-4001
8,000Hz and up - RAAL ribbon
Looking for the best horn to make the most of the TD-4001 in those frequency ranges. Was recommended the Yuichi A-290, and can also get the TH-4001 clones made. Looking for the most transparent setup, and it will be driven with a high quality Linea Research DSP (gasp) and Benchmark / Bryston amps, so we have a lot of tools at our disposal, such as time alignment, FIR, linear phase EQ, etc.
Are there any other horn designs we should be looking at for this? Anything we may have overlooked?
Your help is much appreciated.
Last edited:
Well, me and you have a similar goal...I can say you are pointed in the right direction...I would personally criticize the choice of what appears to be an attempt at a super tweeter? Instead I would point you towards the 18sounds BE compression driver to fit your horn, as well, not needing help at 20khz. You are creating dispersion problems with raal at an 8k XO...
I think you may have hit the nail on the head with the th-4001. Plenty of waveguide choices if you raise the xo to 800 for the tweeter.
I think you may have hit the nail on the head with the th-4001. Plenty of waveguide choices if you raise the xo to 800 for the tweeter.
Greets!
You want transparent, then need a proper conical WG after Dr. Geddes or similar, so most likely DIY.
You want transparent, then need a proper conical WG after Dr. Geddes or similar, so most likely DIY.
In what way would you say a waveguide benefits over the horn in transparency? I know how...but I need to know how you think it does lol
I second the advice to forgo the super tweeter. 2" exit will beam at the last octave but you'll be in the sweet spot. This 90x40 generic Ebay horn is supposedly excellent, there are some measurements and commentary here on this site (not sure exactly where though.) edit": there are two horns here that look similar, not sure which is better...
2" Throat Horn Bolt-On 18"x10"For Assorted Bolt On 2"Exit Drivers 90degx 40deg(398) 647356205293 | eBay
11" x 17" ABS 2" Bolt-On Long Throw Horn 90deg x 40deg For Many 2" Exit Driver 647356202421 | eBay
2" Throat Horn Bolt-On 18"x10"For Assorted Bolt On 2"Exit Drivers 90degx 40deg(398) 647356205293 | eBay
11" x 17" ABS 2" Bolt-On Long Throw Horn 90deg x 40deg For Many 2" Exit Driver 647356202421 | eBay
Last edited:
600hz ?
I wouldn't push the jbl 2384 that low.
The pth horm i have now sounds better, but it crosses at 1,200hz, not 750hz.
I wouldn't push the jbl 2384 that low.
The pth horm i have now sounds better, but it crosses at 1,200hz, not 750hz.
Last edited:
You're kidding, right?!
Regardless, mine was a 'knee jerk' response without paying any attention to the rest, so with a 600 Hz XO, it in theory needs to be a [600/2^4 = 37.5 Hz] Fc for max 'transparency', so ideally need Dr. Geddes' throat design to dramatically shorten it; but assume it will still be too big for the excellent woofer/horn summation a studio monitor app 'demands'.
At this point, what do we have? Tractrix? Not to my ears; LeCleach? Better in theory, but still falls short due to the inevitable throat distortion, so possibly a Dr. Geddes' throat/LeCleach DIY hybrid?
FWIW/YMMV, at this point I've historically used either dual 1" CDs or a point source WG [5"-5.25" for 600-8 kHz] .
A 15" above a 15"? For maximum fidelity/clarity the driver above the sub should not have to make the excursions it does at 60Hz. The xo point is way too low. Otherwise you'd have to use very steep slopes (think about the group delay!) or got a too wide range where both play, the prototype of muddying the sound. You'd better get a 12" with a low mms and don't have to torture the TD-4001 (or different driver) where it has to make too much excursion. The frequency range on its datasheet of 600-20000 does not mean you should xo it at that frequencies! And below it, use a 18" if you really want to go for 20 Hz (which I personally wouldn't).
That is not a well made horn, just look at the mounting plate, casting points not removed, completely uneven, you'd have to plane it first. Okay for low cost "I just want it LOUD!" - but not for these drivers.
The second one is much better, likely with glass fibre or other filler materials, plane mounting plate. But I can guarantee it will not have 90° dispersion except maybe at the bottom end. Expect it to have around ~60°. But for best SQ you have to reinforce it and put it in an absorbing fine sand in its own enclosure. You have to protect the driver from the sand though.
I don't know the Yuichi A-290 but from the pictures I've seen the throat seems to be rectangular. Either you need to build an adapter for the driver exit (round) to the throat (square) or you'll have reflections/interferences and unlinearities.
The Yuichi got a very wide dispersion. You will likely not get that from your supertweeter unless you use the Fostex T925/T825 slot drivers. It seems you have no concept of the dispersion you want. Just scramble something "good" together does not give you a good sound. How does your listening room look like? What will the listening distance be? Multiple big horns need distance to reproduce a homogenous sound and stage. How much are you planning to spend in acoustical treatment of the room?
I agree, that's too low. No need to use the driver outside of their optimum or even good performance range.
I believe they are K-510 clones and have excellent performance. Yeah they are cheap, so what? Build a pretty frame around the mouth and put damping material on the sides. This is DIY. When looking for large horns with good response (I prefer constant directivity) you don't have a lot of choices.
This thread has a lot of great info, including measurements of the horn I linked.
1.4" or 2" throat large constant directivity horns you can actually buy!
I'm all for saving money and I did not say "don't buy it", I said you have to invest time and effort into it because noone else told him, so he probably would just mount the driver onto it and I think that he should know what's up before he buys it. In that price range of the drivers I think it's not the first priority to save 10 bucks on a horn.
I prefer CD horns too, by far. Dispersion is one of the most important attributes of a horn or WG. And that's something he should consider before buying anything, so to suggest horns is not yet helpful. I know you did it with the best intentions but I think it is important to tell him to what the choices lead to (or the other way around). The horn is likely working well but the mounting plate is still wasted potential, don't you think?
Yes, that's indeed a valuable thread. However, it should be emphased that not every horn works great with every driver because of the driver exit often got a step, edge or a seam to the horn. The angle how the driver opens (from straight to angle to a curve) got a good part in it. But again, he should know what concept and attributes his speaker should have (or not have) is more important. So far it (unfortunately) looks like he'd sink a lot of money into it and the result will not be what he imagines what it will be. That's especially important at the Yuichi A-290 horn since it needs an adapter and therefore will not only have one but two of these critical variables. Just picking a horn is simply not enough or as easy as it looks at the first glance.
Do have any proof / paper or measurement data for this statement about jmlc horns and throat distortion?
There are many many different jmlc variants out there with low cut-off, high cut-off, different T values. With T=1 jmlc has the perfect flare rate 1/S dS/dx = const. All have inevitable throat distortions? What is the root cause for this throat distortions? Do you think a perfect pwt causes throat distortions?
Do you think it is better to push a driver by 20dB in a waveguide that does not load at LF for drivers that often only can withstand 1/5 to 1/10th of it's power ratings at the lower part of it's given fr range? This does not produce any distortions?
If I remember well the TD4001 was designed to work excellently together with the TH4001. So this is a proven combination and a very good choice - hard to beat this performance. Throat adapters do harm much less than many believe it well designed.
You are right - but not for the right reasons. This is HiFi. The driver got a lot of headroom, more than 20dB, that is not an issue at all power wise. What is so much more important, at the lower end is no directivity/dispersion control and it has to do too much excursion, which creates distortion.
There are many drivers of manufacturers which sound better with a different horn. The TH4001 and TD4001 work nicely together, no doubt. But that's only an option if 90/40° dispersion is what he needs. So far none of the drivers and horn combinations fit to the other choices, that's simply wasted potential, you can get the same SQ then with a fraction of how much these cost.
YES! EXACTLY! But most throat adapters are not well designed or simply only great for some other combinations. And you can find hardly or even none measurements of them.
If I were designing something like this, I would start with the HF horn. Everything else is going to depend on its behavior. I didn't just randomly post a big cheap horn for no reason at all, I actually think that one is a good place to start. I admit there should have been more context. But so far the only other suggestions have been to get Yuichi customs for $1000 each or build a DIY OS waveguide. BTW my best sounding horns are QSC clones I bought for $11 each on closeout.
One of the links I posted (the first one) shows a high-quality horn casting. It appears to be a Klipsch clone and there are polars of it on this site as well as lots of documentation out there of people using the original. Probably you are not going to find another 2" horn in production (JBL maybe?) that will load the driver down to 600hz or whatever and not have some weird diffraction slot in the throat or isn't ill-behaved in some other way. If I were considering a project like the one proposed I would start here. Honestly I wouldn't be getting TAD drivers either, I'd be looking at recently-designed pro stuff, but that's a different subject.
Last edited:
You are hinting! What are the details behind the formula? Why would you need a Fc of 37.54hz to have max transparency at 600hz? I know this ties into our past dialog where you've said that a horn is better used well above its fc....I just making sure we are on the same page when it comes to why. I can assume I we are on the same page but then my devils advocate argument might miss If I am wrong about your perspective but here goes....
When F is below Schroeder...who cares? Thats that attitude I've received during debates regarding Vented woofers, why not apply it here....The room is going to bury the problem anyway. Right?
37.5hz just leaves me more questions.....if you said F should be 300hz I would of expected it.
Last edited:
The 1 million dollar question....I am no where near the technical level of some in this debate that extends the forum....yet I can see a trend, and looks like this "put the distortion here....no no, put the distortion over here" lol
While there are a lot feasable ways to approach building speakers, in most cases of passive speakers you need to start with the bass. Why? Simply because if the tweeter is quieter than the bass, you can't use it because you can't make it louder. Okay, you will use a DSP, so that's not an issue. Still, the bass dictates how big the speaker will be and what max spl you are aiming for. I know, you want a sub and a 15" for the bass but if you want to reach 20Hz, it will be very challenging for the sub to keep up with the bass. That means, you need either bigger drivers in the sub or build more subs. Either way, that means you are already looking at a likely >300l enclosure.
Also, if you are using horns, they will also add significantly to how to construct the speaker and how big it will be. More important is how the dispersion needs to be. So you need to know the dispersion pattern and of the horns and how to place them onto roughly the ear level - also contributing to the size and shape of the speakers. And of course, how the room looks like, listening position and -distance. Why is the dispersion pattern so important? If you use a 90° wide dispersion in the midrange and place the speakers within ~2-2,5m, you fire into the wall and you'll get early reflections, that has an impact the location of the stage. Worse: It muddies the impulse response, that's where you get your precision, your details - which you said was very important for you. Then you have to get a narrower dispersion, that means, you have to use a different horn, i.e. 60x40°. And naturally, that narrows also your sweet spot. So you need to know your room, how you listen, speaker placement etc.
The (super-) tweeter is the easiest to place or to replace with something else with a different dispersion or horn. You simply have the most freedom to mount it or to change something on it if you realize it's not what you actually wanted.
Sure, you can start with the tweeter but that makes the choices for the rest of the speaker often so much more difficult and forces you to compromises you don't want to commit to.
I didn't say you have to buy more expensive horns. I didn't say you have to use the TAD drivers either, they are very good but (IMHO at least) way too expensive. Modern PA horns got most of the time a better dispersion control over a much wider range, compared to i.e. many HiFi spherical wave horns (even if they claim the opposite).
You can of course use the linked horn but - as I already said - you have to work on it to get a satisfying result which is High End and not PA. The first horn link you've posted is not a high quality horn casting. It may have a nice surface within the horn but it's much worse where it actually is the most important: The throat entry and mounting plate.
To use it, reinforce the horn, put it in a sand chamber, plane the mounting plate, remove the step to your driver opening (if there's any), check the roundness of the throat entry (often not very precise on cheap horns) and remove mold ridges if there any in the throat. But before all that - and that's the most important thing - you have to know if that's the dispersion you need. If not, move on and look what you can use instead. The same goes for every single other part.
I only followed/minimally involved with his new mouth termination of a 0.7T horn, so not being a true WG it will have some throat distortion, but if he later designed some with none, then great, problem solved.
As for the rest of your rant, don't see what it has to do with my on-line 'thinking out loud' musings WRT designing for max 'transparency'.
Didn't mean to......how many octaves is required for a 1st order XO to work correctly WRT sonics?
Correct.
Never given any thought nor recall any docs/whatever to Schroeder WRT horn design, even bass horns.