Greets!
Ideally you don't want any audible output above ~250 Hz from the terminus, so either BW limit its output or use a ~250 Hz tone, then listen a meter or two away and experiment until you can just barely hear it in a quiet room.
WRT damping, all the egg crate foam I've seen is closed cell, which is fairly reflective and has a very low Fs and Q, so ideally you want open cell or similar around the driver or terminus to keep from easily over damping the BW you built the pipe to amplify.
GM
Ideally you don't want any audible output above ~250 Hz from the terminus, so either BW limit its output or use a ~250 Hz tone, then listen a meter or two away and experiment until you can just barely hear it in a quiet room.
WRT damping, all the egg crate foam I've seen is closed cell, which is fairly reflective and has a very low Fs and Q, so ideally you want open cell or similar around the driver or terminus to keep from easily over damping the BW you built the pipe to amplify.
GM
Greg,
WRT foam, damping stuff, chipboard, ply...whatever it may be...old men know their stuff when they see and feel it, but that stops at national borders. Good things (and cheap) may be available a few thousand miles away, but under a different brand name nobody knows! "Global Economy" - kiss my sagging you- know-what.
Pit
WRT foam, damping stuff, chipboard, ply...whatever it may be...old men know their stuff when they see and feel it, but that stops at national borders. Good things (and cheap) may be available a few thousand miles away, but under a different brand name nobody knows! "Global Economy" - kiss my sagging you- know-what.
Pit
Greets!
No doubt true, but being your basic arrogant English only speaking American I can only recommend what's available ~nationally and have to rely on multi-lingual folks in other countries like you to list any local equivalents if available.
GM
No doubt true, but being your basic arrogant English only speaking American I can only recommend what's available ~nationally and have to rely on multi-lingual folks in other countries like you to list any local equivalents if available.
GM
>>> Ideally you don't want any audible output above ~250...
Thanks for that GM. My old Stereophile test CD has a 1k test tone and then drops to 200hz. No output at 1k at all from the opening. I do hear output at 200hz. I will have to look for a 300hz and 250hz test tone. Having these tones can help optimize BIB stuffing. If anyone has them i will put them on the BIB site for download.
Godzilla
Thanks for that GM. My old Stereophile test CD has a 1k test tone and then drops to 200hz. No output at 1k at all from the opening. I do hear output at 200hz. I will have to look for a 300hz and 250hz test tone. Having these tones can help optimize BIB stuffing. If anyone has them i will put them on the BIB site for download.
Godzilla
Zilla,
Get yourself an EMu 0404 sound card. Low end pro-grade stuff, stereo only, can often be found for $60 after rebate (sometimes as low as $80 without a rebate). Guitar Center carries them usually if you like B&M shopping. Anyway, other than being a much better source than your current sound card, and having nearly unlimited tweaking capability in the digital domain, it has a test tone generator built into the drivers.
Kensai
Get yourself an EMu 0404 sound card. Low end pro-grade stuff, stereo only, can often be found for $60 after rebate (sometimes as low as $80 without a rebate). Guitar Center carries them usually if you like B&M shopping. Anyway, other than being a much better source than your current sound card, and having nearly unlimited tweaking capability in the digital domain, it has a test tone generator built into the drivers.
Kensai
Tone generator
Zilla
Re the frequency sweeps CDs. I just did a search for tone generators and found one that allowed me to run tones of my own frequency setting. I then downloaded them into Itunes (Mac based here) and then burned my own CD.
Forget the site I used but the software I have says NCH Tone Generator Swift Sound Software. I'm sure a quick search would find it.
Fo me it gets even more elaborate...as I don't want to run the tone CD all day and night through my valve CDP and amp, so I have recorded the tones onto minidisc and borrowed and old amp from a friend. I now run a subsonic frequency all night that is 21Hz. I can see the drivers moving but I can sleep too!
PS. wife and baby have no idea it is even playing.
Zilla
Re the frequency sweeps CDs. I just did a search for tone generators and found one that allowed me to run tones of my own frequency setting. I then downloaded them into Itunes (Mac based here) and then burned my own CD.
Forget the site I used but the software I have says NCH Tone Generator Swift Sound Software. I'm sure a quick search would find it.
Fo me it gets even more elaborate...as I don't want to run the tone CD all day and night through my valve CDP and amp, so I have recorded the tones onto minidisc and borrowed and old amp from a friend. I now run a subsonic frequency all night that is 21Hz. I can see the drivers moving but I can sleep too!
PS. wife and baby have no idea it is even playing.
Godzilla said:
Reminds me that someone posted a reference group of mp3 tones
here. I got them but that was a few disk reformats ago. It's someplace in this thread. Could that be located and reposted?
Greets!
In a quick search of this thread the only one I found was from the website I listed the other day.
GM
In a quick search of this thread the only one I found was from the website I listed the other day.
GM
open and closed foam
I was thinking of something GM said about open and closed foam.
The only place I've ever seen reference to open and closed foam is
for door/window insulation. That stuff (or some of it) comes as
thick as 1 in for air conditioners. I wonder if that would make a
good surround for the terminus with one or two rows?
I was thinking of something GM said about open and closed foam.
The only place I've ever seen reference to open and closed foam is
for door/window insulation. That stuff (or some of it) comes as
thick as 1 in for air conditioners. I wonder if that would make a
good surround for the terminus with one or two rows?
Tone generator link
Tone generator link I got from this thread a while back.
http://www.nch.com.au/tonegen/index.html
Also pink and white noise which I use too. Free, but you have to load it each time but only takes a few secs.
Martin
Tone generator link I got from this thread a while back.
http://www.nch.com.au/tonegen/index.html
Also pink and white noise which I use too. Free, but you have to load it each time but only takes a few secs.
Martin
I downloaded a free generator called SigJenny from www.natch.co.uk and immediately found that my tweeters were wired out of phase.
A question to GM, Scottmoose or dave. If the bottem end of the divider in the BIB was dropped vertically from its normal end point to the base and then slotted with fine cuts horizontally, as an acoustic filter, would this necessarily reduce the bass response and was this type of acoustic filter from the past really effective at reducing highs.
jamikl
jamikl
For anyone looking for tones, http://www.realmofexcursion.com has a pretty good selection under the "Downloads" section, they also have sine sweeps, warbles, square waves, and bass test tracks...
tones
I got some tones but haven't done any testing before. This is
all done by ear in left/right A/B test mode
I seem to be getting a lot more of everything from the FE127e MLTL
than from the BIB: it's both louder and clearer.
Must be the BIB needs work or the MLTL is perfect. The MLTL has nothing inside-- just an empty box to the specifications from GM but
ported with A 2" diameter pvc port 4 " long.
I got some tones but haven't done any testing before. This is
all done by ear in left/right A/B test mode
I seem to be getting a lot more of everything from the FE127e MLTL
than from the BIB: it's both louder and clearer.
Must be the BIB needs work or the MLTL is perfect. The MLTL has nothing inside-- just an empty box to the specifications from GM but
ported with A 2" diameter pvc port 4 " long.
Greets!
Even the best MLTL will be highly resonant (distorted), so an empty one would be far from technically 'perfect' and more resonant than I can tolerate, though of course this doesn't mean to imply it shouldn't/couldn't sound good to you since we all perceive sound differently for a wide variety of reasons.
That said, the BIB is so much more resonant that in comparison it should drown out the little MLTL, though not necessarily with a similar SQ, so without being there 'up close and personal' with them I'm clueless, especially WRT loudness differences. I mean in theory it would take a prodigious amount of damping to quell the BIB this much. Makes me wonder if the amp's power supply is 'laying down' under the BIB's greater acoustic loading, especially if combined with some series resistance.
What's the general room/speaker layout and signal chain details?
GM
Even the best MLTL will be highly resonant (distorted), so an empty one would be far from technically 'perfect' and more resonant than I can tolerate, though of course this doesn't mean to imply it shouldn't/couldn't sound good to you since we all perceive sound differently for a wide variety of reasons.
That said, the BIB is so much more resonant that in comparison it should drown out the little MLTL, though not necessarily with a similar SQ, so without being there 'up close and personal' with them I'm clueless, especially WRT loudness differences. I mean in theory it would take a prodigious amount of damping to quell the BIB this much. Makes me wonder if the amp's power supply is 'laying down' under the BIB's greater acoustic loading, especially if combined with some series resistance.
What's the general room/speaker layout and signal chain details?
GM
jamikl said:
Greets!
Well, you tell me.......... if a similar device were positioned in your throat between your vocal chords and lips, how do you think it would affect your speech? Wouldn't it increase the loading on your lungs, so that for a given effort it would broadband reduce your speech SPL to its most efficient BW, rolling off both ends of the spectrum like a bandpass (BP) alignment?
GM