That's exactly what it is and having built numerous different aperiodic 'FR', multiway/'IB' TLs and auditioned the B&W Nautilus, none have the effortless presentation of an IB/OB/compression horn IME, but do have much better power handling [except the horn of course], so a good option overall, especially where space is at a premium.
GM
Thanks for the input GM. I'm getting inspired to give this a go. Open baffles would be the best choice for what I want to do, but with the small size of the my office, the leakage would be too much, I think. Big enclosures are the next best choice. I'm going to screw the front panels on so I can make changes inside if I like. I'm also going to make plates out of oak to attach the drivers over a hole in the main panel, so I can easily swap drivers.
It won't just be a set of speakers, it will be a whole messing-around-with-speakers system. It could keep me busy for years. My wife will be so pleased. 😛
It won't just be a set of speakers, it will be a whole messing-around-with-speakers system. It could keep me busy for years. My wife will be so pleased. 😛
You're welcome!
I don't follow, the smaller the room, the greater its room gain BW, so a small OB gapped in a corner mimics a mid-bass BLH and you make it ~71% of corner height and ~evenly spaced in both planes, then you've got an excellent averaged compromise of OB/IB/'BIB' pipe horn.
Anyway, the point is that a small room is your friend when it comes to making [deep/infra] bass in a confined space as proven by mobile audio installs and lots of layout options if 'tall' and/or wall/ceiling locations is combined with corners as was [still is?] common in major recording, broadcast studios.
GM
I don't follow, the smaller the room, the greater its room gain BW, so a small OB gapped in a corner mimics a mid-bass BLH and you make it ~71% of corner height and ~evenly spaced in both planes, then you've got an excellent averaged compromise of OB/IB/'BIB' pipe horn.
Anyway, the point is that a small room is your friend when it comes to making [deep/infra] bass in a confined space as proven by mobile audio installs and lots of layout options if 'tall' and/or wall/ceiling locations is combined with corners as was [still is?] common in major recording, broadcast studios.
GM
Hi PineShack,
A BIB is definitely a 1/4 resonator; it must be at least placed against the front wall, if not right tight in a corner. The walls & ceiling (or floor if inverted) are seen as extensions of the horn mouth. I suspect that if BR offends you, then the BIB would also.
RE: TL -- if you have one end closed and the other end open, you have a 1/4 resonator; IIRC, for a half wave resonator you need to have both ends open.
And I still think that the quick & cheap experiment using a very large cardboard box could tell you a lot.
Cheers, Jim
A BIB is definitely a 1/4 resonator; it must be at least placed against the front wall, if not right tight in a corner. The walls & ceiling (or floor if inverted) are seen as extensions of the horn mouth. I suspect that if BR offends you, then the BIB would also.
RE: TL -- if you have one end closed and the other end open, you have a 1/4 resonator; IIRC, for a half wave resonator you need to have both ends open.
And I still think that the quick & cheap experiment using a very large cardboard box could tell you a lot.
Cheers, Jim
Yeah, I expect it would bother me in the same way. I seem to be oddly sensitive to time issues, not only with sound, but visually as well. With old CRT monitors, for example, the flicker would drive me nuts. I could tolerate 85 hz refresh rate, but just barely. I preferred 100 Hz or 120 on the rare monitor that could do it. I had a friend who saw no flicker at 60 Hz and thought I was nuts. I don't know if it's that my brain is faster in some respect. More likely it's that it's slower. That would be more consistent with the rest of my life experience. 😛
Similarly, I seem to be really sensitive to group delay or whatever you call the various time issues in speakers. BR cabs seem smeared to me. And my first time hearing good full range speakers, with no crossovers messing things up, was a revelation. It was the parallel of a good LCD monitor with no flicker.
The tricks speaker designers use to squeeze more bass out of a cab all seem to smear and muddy the music. To me, it's not like there's more bass being brought out of the music. It's more like cousin Fred decided to play along on the jug.
TLs seem to me that they might not be so bad, though, because there is often little or nothing coming out of the port. If I were going to build a transmission line, I'd skip the elaborate math and just try to make it long enough and well-stuffed that the back wave would grow old and die before it leaked out into my room.
I'm going to ponder this for a while, I guess. I'll likely have a go at the open baffles, seeing as they're so simple to make.
Right now, I'm enjoying the new coupling caps I soldered into my amp this afternoon. I'm still getting the hang of the tube amp thing, but this was a worthwhile venture. No small amount of that mid-range congestion that got me going on the giant speaker enclosure idea is now gone, and I'm pretty pleased with myself. There's enough left bothering me to keep me moving forward with things, but thankfully I now have some laurels to rest on while I drink tea and contemplate my next move.
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??? Stereo is basically mass quantities of comb filtering and with rare exception the bass is summed mono below ~150 Hz on old recordings and guessing they're using the THX 120 or 80 Hz cinema reference nowadays, so even just an 8 ft wall's reflections are going to be below 80 Hz. 'Sounds' like what you want is an excellent headphone set.
GM
Definitely not. 😉 Tapered pipes, horns are 1/2 WL resonators same as an open pipe, plane wave tube, plucked string, etc.: Resonances of open air columns
GM
I guess the issue is I've never tried open baffles. The whole concept of having the back wave bouncing around seems odd to me, and like most people, I fear the unfamiliar. I'm going to give them a try before I build the big enclosures. I'm probably still going to build the big ones, because I've really started to like the idea of having seven-foot-tall nearfield speakers, but I'll try the open baffles first. At the very least, I need to do it as a learning experience. Thanks again for your wisdom.
Glenn - a lot of folks love their OBs and never wanna go back - but rather like large panel dipoles (ESL or magnetic), there are room / placement considerations that can render them problematic.
Hi Chris. Yeah, I expect I'll be doing a lot of reading about open baffles before I bore a hole in a board and call it a speaker. 🙂
This room strikes me as the very definition of problematic, but I'm speaking from a position of ignorance, so I could be wrong. At the moment, it's all bare pine paneling. If reflections are a good thing, then I'm set. Given my preference for accuracy and clarity, though, I'm guessing that correctly implementing open baffles in here might pose some challenges.
I recently picked up a supply of Roxul with the intent of making some acoustic panels. I also bought a measurement mic and a copy of Fuzzmeasure to help me. My initial measurements with Fuzzmeasure were not encouraging. The good folks at SuperMegaUltraGroovy should have included a laughter sound effect that plays automatically for measurements like this.
In another room, with fewer rogue sound waves bouncing around, the speakers themselves do great, other than a surprising hump in the 50hz range, which I wouldn't have expected with four inch drivers in sealed boxes. But as I said, I'm working from position of vast ignorance. Many more surprises await me in this process, I'm sure, but that's where the fun is.
Who knows, I may even try a set of BR enclosures. As I've mentioned above, they tend to sound muddy and smeared to me, but maybe I've just never heard a good pair. Most have crossovers in them as well, and maybe that's part of what I'm hearing. I'd love to hear the F120a in a set of Fonkens. Is it correct, though, that those might be better characterized as aperiodic enclosures rather than a true bass reflex, or as a hybrid at least?
This room strikes me as the very definition of problematic, but I'm speaking from a position of ignorance, so I could be wrong. At the moment, it's all bare pine paneling. If reflections are a good thing, then I'm set. Given my preference for accuracy and clarity, though, I'm guessing that correctly implementing open baffles in here might pose some challenges.
I recently picked up a supply of Roxul with the intent of making some acoustic panels. I also bought a measurement mic and a copy of Fuzzmeasure to help me. My initial measurements with Fuzzmeasure were not encouraging. The good folks at SuperMegaUltraGroovy should have included a laughter sound effect that plays automatically for measurements like this.
In another room, with fewer rogue sound waves bouncing around, the speakers themselves do great, other than a surprising hump in the 50hz range, which I wouldn't have expected with four inch drivers in sealed boxes. But as I said, I'm working from position of vast ignorance. Many more surprises await me in this process, I'm sure, but that's where the fun is.
Who knows, I may even try a set of BR enclosures. As I've mentioned above, they tend to sound muddy and smeared to me, but maybe I've just never heard a good pair. Most have crossovers in them as well, and maybe that's part of what I'm hearing. I'd love to hear the F120a in a set of Fonkens. Is it correct, though, that those might be better characterized as aperiodic enclosures rather than a true bass reflex, or as a hybrid at least?
I'll let you into a little secret.... my Jordan VTL has a removeable rear panel....and most of the time I use them OB with U frame subs
Do OBs do better in a room that has been treated to minimize reflections, or are the reflections part of the charm?
I think the idea is to disperse the reflections not absorb them, and so long as there is sufficient delay, Linkwitz says at least 6mS, the brain doesn't get the direct sound and reflected sound confused, it's the realm of psychoacoustics, he explains it very well. The effect can be hypnotic done well
so, for a certain cohort, any embarrassing blunders can be excused by flashing the seniors' card?
Hi GM, like Scott Joplin this has really piqued my interest - do you mean an OB placed with the baffle at 45 degrees to side and back walls with an even gap to both? I'm guessing some absorbant material needed on the walls behind for mids and highs?
Thanks in advance - with your stock of knowledge and experience you should really write a book 🙂
Works for me! 😀 Sadly, too often I have to fall back on it [sometimes literally due to increasing balance problems 🙁].
GM
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