vangogh-hk said:
Wow, those look scary familiar!!
http://www.diyaudio.com/forums/showthread.php?s=&threadid=3238
Thanks Planet10!
Appreciate it! You guys are doing an amazing job!
Is the dip in response on the BVR between 200-300Hz a problem or is it curable with a supra baffle?
I read the main goal of the Mikasa was to to smooth this area out, which it looks to have done! I can always add shadow later to fill in the bottom but the midrange is more difficult.
Cheers Stroop
Appreciate it! You guys are doing an amazing job!
Is the dip in response on the BVR between 200-300Hz a problem or is it curable with a supra baffle?
I read the main goal of the Mikasa was to to smooth this area out, which it looks to have done! I can always add shadow later to fill in the bottom but the midrange is more difficult.
Cheers Stroop
Stroop,
I had a look last night at the state of the drawings, Mikasa is pretty much ready to go. Scott 7 i never did finalize the compression chamber size. With Iris i'm not sure if Scott & i actually finalized the details... i'll need to go thru the note. The number of designs have come so fast 7 furois it has been impossible to keep up.
dave
I had a look last night at the state of the drawings, Mikasa is pretty much ready to go. Scott 7 i never did finalize the compression chamber size. With Iris i'm not sure if Scott & i actually finalized the details... i'll need to go thru the note. The number of designs have come so fast 7 furois it has been impossible to keep up.
dave
stroop said:
Greets!
These appear to already be half space sims (acoustically infinitely large supra baffles), so as the baffle becomes narrower and/or further from a reflective boundary than the BW, then it will become progressively worse.
Of course this assumes that the sim is accurate (which I doubt it is due to the 'M-T-M' layout) and doesn't take any of the room into account, so may not be bad at all. Only one way to know for sure........GM
As usual, GM's quite right -these are half-space sims. The dip in the response was something I struggled to get rid of for a while -it's only in the more recent designs I've been able to reduce it, usually with adjustments to the throat area. I'm also looking into driver position in the reflex chamber as that too has a significant effect on the smoothness of the response. Idiotic of me really not to consider that little point before...
Having said all that, in practice the dip doesn't appear to be audible -FWIW, I never noticed it myself, and I don't think anyone else did either -no-one mentioned it anyway. The MathCad sims are there as a rough indication of what to expect rather than a definative as the current software can't do a split mouth layout. However, they remain useful as they still give an accurate assessment of F10, and don't seem to be far out with Fc either. They seem to interact with the room nicely anyway.
Having said all that, in practice the dip doesn't appear to be audible -FWIW, I never noticed it myself, and I don't think anyone else did either -no-one mentioned it anyway. The MathCad sims are there as a rough indication of what to expect rather than a definative as the current software can't do a split mouth layout. However, they remain useful as they still give an accurate assessment of F10, and don't seem to be far out with Fc either. They seem to interact with the room nicely anyway.
Bit of both at the moment. I've a set of 126 prototypes in the works though it'll be a while before I get chance to complete them. One's playing sufficently to get an idea of how it will eventually perform (hope I don't regret saying that ). I need to ask your advice on a couple of bits Greg -I'll do that via PM though. The original design itterations took a couple of Japanese boxes as a starting point & developed from there with different lengths & flare-rates (though I'm not too sure just how much difference flare makes with these stepped cabs.) Once these are done, I'll be looking into differential mouth sizes for the upper & lower horns as per your suggestion.
). I need to ask your advice on a couple of bits Greg -I'll do that via PM though. The original design itterations took a couple of Japanese boxes as a starting point & developed from there with different lengths & flare-rates (though I'm not too sure just how much difference flare makes with these stepped cabs.) Once these are done, I'll be looking into differential mouth sizes for the upper & lower horns as per your suggestion.Planet10,
I completely understand! You have a day job too! I've been here to reduce my stress load as it's been crazy in my bizarre little world too.
GM and Scott, I'm sorry I'm a pain with those questions you can't easily answer and that I can't contribute with the intellectual stuff.
The only way I feel I can contribute at the moment is by trying to find interesting drivers to consider, ones that are talked about on German fora etc. I hope it is interesting to you all. If only I had space and more money......
Someone from the Spawn family is definately my next build though and I will swap fe108's between them for fun and give feed back.
Cheers Stroop
I completely understand! You have a day job too! I've been here to reduce my stress load as it's been crazy in my bizarre little world too.
GM and Scott, I'm sorry I'm a pain with those questions you can't easily answer and that I can't contribute with the intellectual stuff.
The only way I feel I can contribute at the moment is by trying to find interesting drivers to consider, ones that are talked about on German fora etc. I hope it is interesting to you all. If only I had space and more money......
Someone from the Spawn family is definately my next build though and I will swap fe108's between them for fun and give feed back.
Cheers Stroop
GM - hard to keep abreast with the young crowd, innit? Gun law in Georgia being as it is, and knowing about your "shy" SPL one wonders how you survive your neighbours' comments anyway.As to the sims coming by the broadside - oh BOY! I use AJHorn, so input has to be done digit by digit...and the prog is notoriously pessimistic.
Greets to an old hand...neighbour just got himself a '68 Bonnie - weren't they luffly bikes?
Pit
stroop said:
Mikasa 0v921 is posted on the Spawns page. This is being released pre 1v0 with only the recommended compression chamber to determine. As per the notes it is suggested that any early build be done with an enlarged CC -- it is a lot easy to make it smaller after being built than to make it larger.
http://www.frugal-horn.com/spawn.html
The way the CC is formed on this one gives the opportunity to create a truly non-retangular CC.
This drawing also has another tidbit -- a fairly accurate calculation of the volume that the back side on an FE126e displaces.
dave
OK guys, I've given up on work for today (too many armoured cruisers makes Scott a dull boy), and I'll spend this evening working on Mikasa's CC. Going by memory, I was looking at ~3 litres which seemed to give the best compromise between overall FR, and impulse response, which rings like a bell if you go too small. Sorry it's taken so long -got distracted by other cabs, + work. Dave -you'll have PM shortly.
