I think it's gonna be very hard to find something better with that much juice in that price range, as long as it's not breaking down. A potential breakdown would be the only thing to worry about and if you want better reliability you need to pay 5 times as much or go heavy weight.
Look if you can find SAE pxm or pcm, or pqm if you want 4 channels.
T.amp also has reliability issues.
Look if you can find SAE pxm or pcm, or pqm if you want 4 channels.
T.amp also has reliability issues.
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pcm or pxm series, depending on your budget and such. I would atleast get one with around 1000w at 8 ohm in your case.
TH18 with cone correction
In which post can I find the plans for these cabs with cone correction?
and a GOOD OKTOBER to you all !
My newest pile of saw dust,,,,,,
In which post can I find the plans for these cabs with cone correction?
soooo things are lining up
Been busy building and cutting the angles, hopefully tomorrow I can glue everything together! Gonna do two of these, with djims cone correction.
I still have to cut the braces and some little reflectors. Would it be a shame not to cut cutouts in the braces like everyone does? Weight doesn't matter to me, does that affect the sound though?
We will load the cabs with the 18sound 18TLW3000...
Watch out for a report ;-)
Greets, Fabio
Been busy building and cutting the angles, hopefully tomorrow I can glue everything together! Gonna do two of these, with djims cone correction.
I still have to cut the braces and some little reflectors. Would it be a shame not to cut cutouts in the braces like everyone does? Weight doesn't matter to me, does that affect the sound though?
We will load the cabs with the 18sound 18TLW3000...
Watch out for a report ;-)
Greets, Fabio
Hello,
First of all thanks a lot to Martin (Xoc1) who shared this great design with the community and to all guys that help him in this journey.
It was very addictive to read all thread from beginning and see some optimization tries but one maybe i miss was related to S3, did someone tried to increase this section?
Playing with simulation it indicates some improvement on the LF response and comparing with Danley solution looks like he went in that direction.
I know the Martin idea is DIY and copy Danley's solution will against copyright but in some way there is some margin there to work.
Take a look at the comparison (the throat adapter and the path increase was already discusses in the past but i didn't saw the results one the plan was no available, just sketches).
First of all thanks a lot to Martin (Xoc1) who shared this great design with the community and to all guys that help him in this journey.
It was very addictive to read all thread from beginning and see some optimization tries but one maybe i miss was related to S3, did someone tried to increase this section?
Playing with simulation it indicates some improvement on the LF response and comparing with Danley solution looks like he went in that direction.
I know the Martin idea is DIY and copy Danley's solution will against copyright but in some way there is some margin there to work.
Take a look at the comparison (the throat adapter and the path increase was already discusses in the past but i didn't saw the results one the plan was no available, just sketches).
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
The DIY design/fold originated with James Bell, it was not intentionally an attempt at a copy of anything.
Over the years Tom Danley has been quite helpful to the DIY community, out of respect we do not publish copies of his commercial work.
The edit button is not more available for that post to edit it
Are you able to delete it or know and admin to do it?
You could take them down at the image host, everyone subscribed to the thread has received the links...
Done so let me ask apologies and back to the point with different image.
Did someone tried to increase S3 section? looks like it benefits the LF extension
so let me ask apologies and back to the point with different image.Did someone tried to increase S3 section? looks like it benefits the LF extension
An externally hosted image should be here but it was not working when we last tested it.
There are lots of things that can be changed in order to try to eek a bit more performance.
Increasing S3 probably makes a difference. But then do you reduce all the other dimensions to keep the volume the same or are you making a bigger box?
If you spend an age reworking the geometry to keep the box volume the same but with a bigger S3 you will probably find the difference is minimal.
S3 in the Danley design is bigger - but probably because the TH118 was originally a TH115 and then had an 18" driver squeezed on to the 15" baffle while as many dimensions as possible were kept the same.
Probably the way to go is to make the box bigger front to back in order to have enough room to increase S3 but this can cause other problems, I have found that it caused a loss in performance around 100hz.
With a decent driver it is possible to upscale the whole box and then you end up with something similar to Epa's drawing in the 30hz thread in post 773
http://www.diyaudio.com/forums/subw...30-ft30-pa-th-awesomeness-78.html#post4376089
As ever making a speaker is all about which compromises are important to you!
Regards
Xoc1
Increasing S3 probably makes a difference. But then do you reduce all the other dimensions to keep the volume the same or are you making a bigger box?
If you spend an age reworking the geometry to keep the box volume the same but with a bigger S3 you will probably find the difference is minimal.
S3 in the Danley design is bigger - but probably because the TH118 was originally a TH115 and then had an 18" driver squeezed on to the 15" baffle while as many dimensions as possible were kept the same.
Probably the way to go is to make the box bigger front to back in order to have enough room to increase S3 but this can cause other problems, I have found that it caused a loss in performance around 100hz.
With a decent driver it is possible to upscale the whole box and then you end up with something similar to Epa's drawing in the 30hz thread in post 773
http://www.diyaudio.com/forums/subw...30-ft30-pa-th-awesomeness-78.html#post4376089
As ever making a speaker is all about which compromises are important to you!
Regards
Xoc1
Hi Xoc1,
I was addicted to ready all pages about TH18 and very optimistic to build some, almost all was prepared till i start simulations and see a big problem, i found 2 driver that give me the same performance as the original drive bu the problem is the diaphragm displacement, due to Xmax limit i need to reduce too much the power.
Would you mind to give me some tips?
How can I tune your design in order to reduce diaphragm displacement? maybe i will need to trade off SPL to keep the bandwidth. I like the bandwidth you choose.
I was addicted to ready all pages about TH18 and very optimistic to build some, almost all was prepared till i start simulations and see a big problem, i found 2 driver that give me the same performance as the original drive bu the problem is the diaphragm displacement, due to Xmax limit i need to reduce too much the power.
Would you mind to give me some tips?
How can I tune your design in order to reduce diaphragm displacement? maybe i will need to trade off SPL to keep the bandwidth. I like the bandwidth you choose.
Can you post the specs of the driver you have chosen and maybe the sim exported from Hornresp?
Don't forget that in the real world you will need to probably double the amount of power to take account of thermal compression to achieve x-max. The ultimate limit is to avoid x-mech of course.
The goal is to shift air, and that is limited by the driver. Have you used the Hornresp filter wizard to see which high pass filter is most suitable? You may find that you need a higher frequency filter or a lower order filter to roll off the bottom end more gently.
As I said compromises!
Don't forget that in the real world you will need to probably double the amount of power to take account of thermal compression to achieve x-max. The ultimate limit is to avoid x-mech of course.
The goal is to shift air, and that is limited by the driver. Have you used the Hornresp filter wizard to see which high pass filter is most suitable? You may find that you need a higher frequency filter or a lower order filter to roll off the bottom end more gently.
As I said compromises!
There is a direct relationship between the box volume and efficiency at low frequencies. Shuffling panels around in the box without increasing the net box volume may affect what the passband looks like, but probably won't affect efficiency at low frequencies much, if at all.
Going by your image, if I was going to change anything without seriously shifting around panels, I'd change the net box volume by perforating the panel at point A in the diagram and possibly stuffing that section a bit. That should push the resonance frequency a little lower and smooth the out of band response a bit. If I had the opportunity to shift around the panels though, I'd go with the layout I used for my POC4 design, which incorporates cone compensation and results in a longer path length for the horn in the same volume.
Attachments
Xoc1, thanks a lot for you time. I didn't tried to use filter for a while. Could this be the piece I'm missing to fix the displacement issue?
The drivers i'm planing to use are one of those two: Keysbass KSPA-18-1200 or Oversound SUB-800. The T/S parameters are on the table below and the input data i'm using on the hornresp too.
The issue regarding diaphragm displacement could be some misunderstanding from my side that you experience can bring some light as the filter.
The drivers i'm planing to use are one of those two: Keysbass KSPA-18-1200 or Oversound SUB-800. The T/S parameters are on the table below and the input data i'm using on the hornresp too.
The issue regarding diaphragm displacement could be some misunderstanding from my side that you experience can bring some light as the filter.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
