I posted the link to other thread because i am not the only one who has the experience with fullrange + tweeter = improved bass...hence the link.
I am not going the discuss supertweeters, that would be side stepping from the thread about line arrays. But most of the time people use supertweeter with just one cap. First order, even crossed very high, will bring wider dispertion of heights below crossover point (due to shallow slope), thus helping to improve beaming fullrange.
Something like i did here...
https://www.diyaudio.com/forums/ful...e-enclosure-tb-w5-1611-saf-4.html#post5741735
https://www.diyaudio.com/forums/ful...e-enclosure-tb-w5-1611-saf-4.html#post5741735
Wouldn't the recording microphone pick up the 3Khz for you? In other words, you wouldn't need the 21/24Khz to reproduce the 3Khz result.
As far as I know, no .... this is a property of the auditory system of the human ear and how the ear interprets and transfer the signals, I have never tested this, but would like to do.... I do have tweeters that should make this testable
F. Alton Everest wrties about these things in master handbook of acoustics Alton writes as follows
The auditory system may sometimes play tricks on our perception of sound.
Plug one oscillator into the left channel and the other into the right channel and adjust both channels for an equal and comrortable volume lever at some midband frequency. Then tune the oscillator to 23 KHz and the other to 24 KHz without changing the level settings. With either oscillator alone, nothing is heard because the signal is outside the range of the ear. However, with both signals, if the tweeters are good enough, you may hear a distinct 1 KHz tone.
The 1 KHz is the difference between 23 and 24 KHz. The sum, 47 KHz is another sideband. Such sum and difference sidebands are generated whenever two pure tones are mixed in a nonlinear environment. The nonlinear environment in this case is the middle and inner ear. In addition to intermodulation products, the nonlinearity of the ear generates new harmonics that are not present in the sound falling onto the eardrum.
Last edited:
Minor update, cabinet #2 is now prepared to be filled with EG, work start this evening and I will cast in increments over a couple of days
Glad to read there is steady progress. You'll get there.
Minor update, cabinet #2 is now prepared to be filled with EG, work start this evening and I will cast in increments over a couple of days
Very Interesting progress
I’m pretty sure there will be a big improvement to Mk I.
30kg worth of EG cast in place, now I need to get some sleep before work, so I can do the last 20kg or so.... Each 10kg require about 1h30min from mixing to compacted, a lot of small areas that need to be filled properly as the EG do not flow one mm by itself 
If the last 15-20kg can be cast tomorrow I should be able to pull the liners on thursday/friday....
If the last 15-20kg can be cast tomorrow I should be able to pull the liners on thursday/friday....
30kg worth of EG cast in place, now I need to get some sleep before work, so I can do the last 20kg or so.... Each 10kg require about 1h30min from mixing to compacted, a lot of small areas that need to be filled properly as the EG do not flow one mm by itself
If the last 15-20kg can be cast tomorrow I should be able to pull the liners on thursday/friday....
With that extremely low viscosity isn’t there a pretty big risk you get som void’s in there that could give you unwanted internal resonances?
or is that a non-issue or, do you have that thing under control too?
Hi haraldo,
Think it sounds/looks HalAir works with overview in build process, you know concentrated and organizational and also think remember he did some quality "tap test" on cabinet #1 to search for "hollow", below is some visual history from cabinet #1 process, that said imagine there will be plenty of resonances down the road when feeded some track materials ...
Think it sounds/looks HalAir works with overview in build process, you know concentrated and organizational
and also think remember he did some quality "tap test" on cabinet #1 to search for "hollow", below is some visual history from cabinet #1 process, that said imagine there will be plenty of resonances down the road when feeded some track materials ...Attachments
Last edited:
With that extremely low viscosity isn’t there a pretty big risk you get som void’s in there that could give you unwanted internal resonances?
or is that a non-issue or, do you have that thing under control too?
There is the chance of that, taking it slow reduce the risk - but on my first cabinets there were some voids and a few holes in the interdriver chamber walls.
What kind of effect it may have on resonances I dont know, but dont think it will affect much
Everything under control? Hardly
Another milestone have been achieved, cabinet #2 is cast.
47kg sand and 5,6kg epoxy was the grand total and its now left to cure until friday
Another 5-6kg will form the rearwalls, scheduled for this weekend.Its getting heavier than anticipated, per line:
58kg of EG
30kg of wood/MDF
7kg of drivers
Weight vs mms is approaching 1700:1
Excelent numbers
re below imagine when haraldo gets by for audition there's big chance TC9 get a Pink Floyd ready stamp, in past we heard Roger Water tracks on wesayso's system and what a pleasure.I unfortunately did not yet audition any speakers with the tc9, but many times... over and over gain with the tg9, and there is only one thing to say, they take my breath away...
Once I was listening to Pink Floyd, the wall, and I would swear it had to be another mastering because of the detail, the dynamics, the realism, the sheer incredible attack and lveliness of the voices.... ot was same mastering, insane
I doubt I will be able to take this up to Ronalds level of perfection considering all his efforts over the past years with his towers
But I'm sure I'll have plenty of fun with mine
So far its been mainly hard labour
Regarding voids, due to the cramped volume the EG is forming into there is no chance of consealed voids, like bubbles trapped inside the matrix.
On cabinet #1 there vere two voids towards the cabinet, where a small area didnt have EG at all - but these were easily remedied after the liners were removed.
Last edited:
... that said imagine there will be plenty of resonances down the road when feeded some track materials ...
Its impossible for a system not to get aggitated to a certain level, hopefully the obstructive ones are attenuated well within my system. There will be resonances, and most of them will travel out through the driver.
I have started with less stuffing compared to my mk1's and I hope to find a little time to finalize that aspect before finishing up line #2. So far I have been focused on the casting which was a tedious process. If I ever is to do this again it will be simplified
If it can help for stuffing process find a zma file hang on below into a zip folder, its the curve of wesayso's build and think it can be used as kind of good refference or textbook overlay : ) its the blue curve in below Xsim overlay and the grey curve is one of my own TC9 curve into free air. Admit i haven't asked wesayso permission to share file but in the visuals is shared over in towers thread anyone can do the tracing act : )...
Attachments
Last edited:
Shame on you!
Just kidding... observe the fine wiggles in impedance tests. Stuffing should get rid of those. Leave some free room behind the driver(s). I bet your results can be great with denser stuffing the further you get from the driver. If you use fiberglass stuffing it might make sense to have another material between it and the driver. I used (real sheep) wool felt for that.
Just kidding... observe the fine wiggles in impedance tests. Stuffing should get rid of those. Leave some free room behind the driver(s). I bet your results can be great with denser stuffing the further you get from the driver. If you use fiberglass stuffing it might make sense to have another material between it and the driver. I used (real sheep) wool felt for that.
The first tower is lined with 8mm felt all-around and 10g of Knauf Glass Mineral Wool for each chamber. It occupy roughly 1/3 of the chamber volume.
Preliminary impedance tests in the test chamber showed promise, but compared to my mk1 its only 50% of what I used there
Using two different medias for stuffing will most likely be more efficient and overstuffing the test cabinet with Knauf made the curve drag and a shelf to the left. (measurements are crude and not with a calibrated circuit as the resistor value for REW is not within spec)
I havent measured the first tower yet but want to do individual driver / full line plots when time allows it.
As I use two individual groups of 12 per line I also need to pay attention to make sure they are similar in behaviour.
Attachments
Last edited:
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.