What about this tweeter?

Tymphany OC25SC65-04
(Can't post links or photos yet)

It might be low profile enough to be contained in the bottom of the unit, allowing a flat bottom which could be mounted anywhere on the dash without needing a mounting hole.

Another option would be a blank flange on the bottom and a cutout for a typical 1" tweeter with screw mounted faceplate. The screw holes can be drilled by the end user to accommodate their tweeter of choice.

I would be interested in a pair of waveguides if you are printing them.

-David

 

This works for me.

For a SAW lens you want as little flange as possible. For instance, I have some Dayton RS28s here, and they don't work so hot for this stuff because the exit on the dome is actually close to two inches across, even though the dome itself is just a bit over 1" in diameter. The extra space at the exit screws up the wavefront, because you need a small exit for a good wavefront.

 

**** yes! ive been thinking about trying to make a mold out of these somehow, but wasnt sure. how do you think it would work for the scanspeak R2904? i highly doubt you will be making a large amount for that tweeter since i only know one or two other people with this tweeter, but i would definitely buy a pair, or even just pay for the 3d model of it.

 

What frequency range do you estimate the waveguide to have pattern control over? Also, could the rear top portion of the assembly be tapered to more closely match the profile of the waveguide? This would allow it to be pushed further into the corner of the windshield and would look less like a coke can sitting on the dash.

 

What frequency range do you estimate the waveguide to have pattern control over?

Basically the lens takes one octave of sound and it bends it at a right angle. It doesn't work over a wide bandwidth.

One of the reasons that B&O put the tweeters forward of the rear glass in the Aston Martin and in the Audi is to reduce early reflections off the glass.

Also, could the rear top portion of the assembly be tapered to more closely match the profile of the waveguide? This would allow it to be pushed further into the corner of the windshield and would look less like a coke can sitting on the dash.

This would be another way to do it.

If you're going to push it all the way back into the glass, you *might* be better off with a plain ol' waveguide. If you take a look at the polar response of one of the B&O lenses, you'll see that it's actually cardioid. Here's what I mean by this:

1) a regular waveguide sends all the energy in one direction. You get that 'giant headphone' effect. Very analytical, detailed. It can also tend to lack ambience. (Because there's very little reflections.)

2) a cardioid, like the SAW lens, sends *most* of the energy in one direction. But it also scatters some to the rear (some, not all.) So you get a more 'spacious' sound.

It is true that the SAW lens can be used like a plain ol' waveguide, and B&O did that in some Mercedes. But in the conventional setup, like most of their systems, it's a cardioid.

 

Dayton Audio AMT Mini-8 Air Motion Transformer Tweeter 8 Ohm

The AMTPOD I think is the the same physical dimensions once out of the cups. I can measure mine sometime today. You need diaphragm size? They are made by

Edit: Found the diaphragm size of the AMTPOD on Madisound website 19mm x 19mm (they are made by Tianle and rebadged as Dayton at parts express)

 

I have neo3 b&g and neo8 b&g I have used as tea tweeter and love the way they sound as a tweeter however , I have wanted to try this one, it says very high output , but a 15w rms rating worries me especially at 88db.
Do these really get loud without blowing? Could you put a 100w car amp on them safely?

 

What is the lowest frequency playing neo tweeter that there is? I vote for that one.

 

I vote the SEAS Prestige 27TFFNC/G (H1396) 1" Textile Dome Tweeter
Or the hard dome. Common size & shape. Well known performance.

 

i think the best choice for this would be the scan d3004 or r3004 since 1) theyre amazing tweeters for a good price, and 2) theyre definitely the most popular

 

I haven't paid more than $75 for a tweeter in a decade :O

I could probably throw together something generic that would work with a ScanSpeak, but I can't figure out why they're five times more expensive than Vifa. (Besides the obvious - they're made in Denmark.)

 

Id definitely be interested once overall dimensions are know. I agree on using the Scan Tweeter

 

Im getting turned on by reading this thread! Lol but seriously, im very interested in seeing where this goes! I know typically the lens is positioned on the dash, but how would it work if it was rotated 90 degrees and positioned on the A pillar?

 

i was just about to ask this. my tweeters are 4 inches in diameter and pretty much need to be on axis, so it makes for some ****ty blind sponts, especially in a small 2 seater sports car. i was thinking maybe mount them firing across the dash, but the lens sideways towards the center

 

I believe Mercedes used a similar technique

 

Oh wow!!!!!! That looks bad ass!!!

 

i worked on (i think a mercedes) back when i was working in the city, and when you turned the radio on, two of these lenses rose up out of the corner of the dash. it was pretty sweet

 

The audi A8 had the lens that rose from the dash. Impressive to see in person.

 

That might have been it. It was either a Benz, Audi, or Lexus

Sent from my HTC6525LVW using Tapatalk

 

any way to just make the lenses "universal" fit for a 1" tweeter? I think youd get more takers that way. Also gives people more options without having to hack something apart to get to what they want.

 

Sure.

Just pick your entrance diameter and that determines everything else.

For instance, you could have a one inch entrance for compression drivers and 3/4" tweeters.

A 1.25" entrance for 1" tweeters. Etc...

 

Dibs on a set.....im in.

 

mr bateman, is there a specific and exact shape and width/length, or tuning to these lenses?

 

Yeah, the whole thing is fairly simple.

You start with this, your basic spiral designed by mother nature

Do the math, you got yourself a Fibonacci Spiral

Overlaid with the real thing

read more here : Cloning a $3200 Speaker for $400 - diyAudio

 

Sub'd! Very interesting project..

 

Perhaps something for the Sinfoni T25T tweeter.. I know of a few guys that would try it

 

The faceplate messes it up.

I have no idea what these cost, but they don't look cheap, and I wouldn't ruin an expensive tweeter just to cram it into a lens.

Stick with the $25 Vifa, it's nice

 

I'd be on board with a lens for the T25T....

 

I was in a friends BMW the other day with the B&O sound package. She has a single center speaker with this lens that drops down flush with the dash, the lens intrigued me, and the single, center driver reminded me of an old thread here (also started by Patrick, I believe) about the effectiveness of only using a single tweeter in the center of the dash.

I would be interested in trying both of these concepts out simultaneously in my car.

 

Those B&O guys know what they're doing. I've long thought that the SAW lens would work nicely as a coaxial. But I'd always put them right on top of each other. (I made a couple, I can probably dig up the pics.)

The problem with a coax, in this situation, is that it gets tall in a hurry. The ones that I made were something like 6" tall.

It hadn't occurred to me that if you offset it, you're still within one wavelength at the xover point. So it's fairly simple to get good polar response. (A little DSP would go a long way here too.)

Heres the lenses from the Aston Martin

The Mercedes version always seemed a bit silly to me. A plain ol' tweeter in the A-Pillar would be cheaper and work just as well or better. One of the big advantages of the SAW lenses is that you can line up all the drivers on the same axis, and you can keep the height to a minimum.

 

These SAW lenses really do look to be a great option... relatively compact with controlled dispersersion...

I like it...

 

If this thing over 3" in diameter then my interest starts waning. too large and much work to integrate how I would want to in the dash

http://www.ebay.com/itm/No-3-Audi-A...ted-B-O-type-auto-rising-tweeters-set-/321753736158?hash=item4aea0463de&vxp=mtr

 

If this thing over 3" in diameter then my interest starts waning. too large and much work to integrate how I would want to in the dash

No 3 Audi A4 A5 A6 A7 A8 Q5 All Fitted B O Type Auto Rising Tweeters Set | eBay

What's the plan? Add some 'sparkle' to your compression drivers? Or are you thinking about going with dome tweeters?

A dome tweeter with high power handling would be a good match for either option.

I like point source arrays, but I can understand if some people want to spread the drivers apart.

 

So you would need a "naked" driver? Just the magnet assembly and soft dome with no housing to do the SAW application? Hmmm.. That would be a pricy trial.

I have a few BNIB pairs of Vifa ring tweeters around here

 

Yep.

When something is close to a tweeter, a difference of 1/4" makes a huge difference, because 20khz is less than an inch long.

That's why the 'naked' Vifa tweeters suggested on the first page are such a good fit.

Plus, lets be realistic here, 80% of the expense of the B&O lenses are those ridiculous CNC milled aluminum bits. You can get the same results for $50 if you make it out of plastic.

 

This is probably a really stupid question, but is there any advantage to using this acoustic lens versus mounting similar tweeters in "orbs" (same dash location) and aiming at the listener on-axis?

What are the pros/cons comparing these two mounting methods? Since the lens dispersion is still essentially cardioid, what is the diff?

 

it goes back to the box shapes, with diffractive changes for most shapes but the pretty response curves goes to the cylinder (a-la-Pluto) and the sphere, or orb.

when you put the thing in an omni mount, but cut the back half of radiation out, it concentrates the acoustic energy in the forward field, whether or not you "sausalito" it out or just add a baffle.

the nice thing about this design is that the windshield and the dash, in some vehicles form a natural waveguide that should address lower frequencies, there's no need for platters above and below. The sausalito itself throwing the top octave forward means there is a portion of the audio that is naturally narrowing the vertical dispersion, and the normal dash sound of early reflections is tamed and the clear response of the tweeter can play through. The only problem is that the baffle will block some people's vision of the road, based on how they sit in a car. Having a dash with factory holes that you could squeeze a compression driver into, then using the Sausalito principle of reflector/baffle logistics above the drivers, could bring some extra definition to the highs and possibly upper mids as well.

Anything that controls the dash/windshield sound field to allow dash mounting a driver but getting 180 degree forward radiation from it, sounds like a step in the right direction.

pointing the tweeter in an orb is doing nothing at all to suppress those first bounces above and below the pod, and leaves the "veil" in place.