I'm planning to build the Manzanita and am wondering if it makes any sense to build it taller and move the drivers up higher. Plans call for the center of the SLS woofer to be 13" above the floor and the center of the Vifa full range to be at 22.5".
It would very easy to make the baffle about 14" taller and bring the Vifa up to listening ear height at about 36" while maintaining the same distance between it and the woofer. There would more baffle, or just open space, down to the floor. The question is whether that's a good idea or not.
It would very easy to make the baffle about 14" taller and bring the Vifa up to listening ear height at about 36" while maintaining the same distance between it and the woofer. There would more baffle, or just open space, down to the floor. The question is whether that's a good idea or not.
It always matters. But you need really thick, heavy carpet to attenuate LF floor bounce. Most carpet is just going to attenuate hi-mid bounce. And that's OK. John might have a better idea with this particular crossover. Baffle size also effects baffle peak, so that needs to be taken care of in the crossover.
The speaker is easy enough to build that a couple of test baffles wouldn't be too much trouble or expense. You'd at least get a feel for it in you room.
The speaker is easy enough to build that a couple of test baffles wouldn't be too much trouble or expense. You'd at least get a feel for it in you room.
I'm afraid that what we have, in fact, IS very thick carpet and it's over an equally thick pad. The combination is probably about as thick as you can get. It's like walking on sponges.
So where does that lead me for floor bounce issues? Would it be good to move the drivers up? I could easily do that.
So where does that lead me for floor bounce issues? Would it be good to move the drivers up? I could easily do that.
Update, I found with the bypass capacitor, the highs were a bit harsh and the speaker became a bit tiring to listen to. I have a concrete house and I dont know if that was contributing to the fatigue. My investigations with Xsim and with parts on hand lead me to flatten the impedance on the top end. I utilized two 0.33uf and a 15 ohm resistor. So far so good. The bass now sounds a little more punchy and the mids sounds a bit more flat which I prefer.
Yes, as 'pano' mentioned those metal can 'motor-run' caps are readily available for a try. I have collected quite a few different ones over the years and some exotics too - I did like those Anpohms when they were available and some jensens too buyt …
it's really a bit of a 'crap-shoot' as some of those ugly cheap Russian ones are excellent and just as good as some expensive exotics - you're over in Trinidad, yes - perhaps you can ask over in Cuba about some of the older parts - they do age well but just don't crack them open! have a 'scratch around' in the repair centres for some of the older big can ones like Siemens, Rifa, etc
Also, wall/room treatment might be worth a bit more attention - a favourite subject of mine!
Ahh, mr 'classicalfan' - just put a box, or something, under your speakers and see what difference it makes - try small like a couple bricks (4"), etc - an old trick for 'woofy' subs.
it's really a bit of a 'crap-shoot' as some of those ugly cheap Russian ones are excellent and just as good as some expensive exotics - you're over in Trinidad, yes - perhaps you can ask over in Cuba about some of the older parts - they do age well but just don't crack them open! have a 'scratch around' in the repair centres for some of the older big can ones like Siemens, Rifa, etc
Also, wall/room treatment might be worth a bit more attention - a favourite subject of mine!
Ahh, mr 'classicalfan' - just put a box, or something, under your speakers and see what difference it makes - try small like a couple bricks (4"), etc - an old trick for 'woofy' subs.
So if I understand it correctly the idea with a heavily carpeted floor is to move the woofer up higher than you would with a hard floor. And the exact amount is more a matter of trial and error than something that can be calculated.
I guess the idea is that you don't want to lose a lot of the bass energy by it being absorbed by the heavy carpet. By moving the driver up the energy goes out more directly into the room even though it's now going to be more direct instead of being reflected off the floor. It seems to me also that there is now going to be more ceiling reflection as well. Does this all make sense or I am missing something?
I guess the idea is that you don't want to lose a lot of the bass energy by it being absorbed by the heavy carpet. By moving the driver up the energy goes out more directly into the room even though it's now going to be more direct instead of being reflected off the floor. It seems to me also that there is now going to be more ceiling reflection as well. Does this all make sense or I am missing something?
No, ceiling reflections are often ignored along with much of the room interactions too so it's a 'try-it-and-see' situation to begin your 'learning experience (yes, I'm serious - you'll learn more about your sound by just moving your speakers in a systematic way) - the room itself generally creates most of the compromises and once you get used to this idea, then your approach to speaker performance will become more flexible - your new 'bible' will be "try it, write it (notes) and listen slowly"!
There's a guy called Jim Smith who wrote a book 'Get Better Sound' about 10 years ago and worth every cent for open minded 'fiddlers' like us if you can find a copy (not sure if still available from his website) - it's a really common sense approach to setting up systems and lots of other 'goodies' like learning how to listen, etc.
Every 'hifi' shop should have had this as basic study/reading but, alas ...
There's a guy called Jim Smith who wrote a book 'Get Better Sound' about 10 years ago and worth every cent for open minded 'fiddlers' like us if you can find a copy (not sure if still available from his website) - it's a really common sense approach to setting up systems and lots of other 'goodies' like learning how to listen, etc.
Every 'hifi' shop should have had this as basic study/reading but, alas ...
There seems to be some difference of opinion with regard to ceiling reflections. Here is a video with Clayton Shaw of Spatial Audio discussing room interaction with open baffle speakers. If you start at about 19:30 minutes you'll get right to the important stuff.
WHY OPEN BAFFLE RULES - with Clayton Shaw | Spatial Audio - YouTube
WHY OPEN BAFFLE RULES - with Clayton Shaw | Spatial Audio - YouTube
Yes, the OB setup has less ceiling reflection interference problems true, because of the side/top edge cancelling characteristic but it still acts as a 'first reflection' point and can benefit from absorption at that position, just like sidewalls - also, many ceilings use a type of 'plaster-board' and this doesn't reflect sound like a solid wall so less interference.
It's good to read up on these subjects and expect some contradictions too - many of us think we're right about all sorts of things but when you get older, like me, you realize the opposite!
It's good to read up on these subjects and expect some contradictions too - many of us think we're right about all sorts of things but when you get older, like me, you realize the opposite!
Floor bounce generally gives you a dip in the bass response where the reflection and the direct sound meet and cancel out each other. The distance between the floor and the woofer is obviously going to change the point at which this happens.
You're going to have to get your hands dirty and make sawdust. Build the baffles you want, even out of cheap materials, and test them. The Manzainita crossover is going to be a solid starting point for finding what works in your room with your new baffles. You'll get there, it will just take time.
FWIW, you likely won't have to change the woofer inductor value. You'll end up playing with the woofer shunt cap, the series resistor on the tweeter and maybe the tweeter cap values.
You're going to have to get your hands dirty and make sawdust. Build the baffles you want, even out of cheap materials, and test them. The Manzainita crossover is going to be a solid starting point for finding what works in your room with your new baffles. You'll get there, it will just take time.
FWIW, you likely won't have to change the woofer inductor value. You'll end up playing with the woofer shunt cap, the series resistor on the tweeter and maybe the tweeter cap values.
So if I understand it right, this is all due to my very thick carpet since the design assumes a harder type floor surface. Which leads me to think about other DIY designs as well as commercial products.
If the basic assumption by virtually all speaker designers is a reflective floor, then someone like me with thick carpet would always have to make adjustments. And that might not be very easy with a commercially built product. I wonder how many people who buy finished speakers understand that. Or if the instructions from the manufacturers even mention it.
My thinking now is to build a baffle that attaches to a tall stand and can be moved up and down easily with just a few screws holding it in place. So the next question is about the gap between the floor and the bottom of the baffle. Should that be left as an open space, or filled with a blank panel so that there is no gap? Or does it even matter?
If the basic assumption by virtually all speaker designers is a reflective floor, then someone like me with thick carpet would always have to make adjustments. And that might not be very easy with a commercially built product. I wonder how many people who buy finished speakers understand that. Or if the instructions from the manufacturers even mention it.
My thinking now is to build a baffle that attaches to a tall stand and can be moved up and down easily with just a few screws holding it in place. So the next question is about the gap between the floor and the bottom of the baffle. Should that be left as an open space, or filled with a blank panel so that there is no gap? Or does it even matter?
It does matter if you leave it open or filled. The original Manzanita baffle was made to sit on a stand with open space under the baffle. That puts it about ear height.
Floor bounce is usually in the area of 200Hz, but that varies with geometry.
Here is a calculator to help: Floor/Ceiling Reflection Calculator
And more info:
SBIR calculator
audio blog: A little more into boundary conditions
Floor bounce makes notches in the response. Having thick padded carpet will be a big help at mid and high frequencies, less help down low because of the wavelengths involved. At 220 Hz that's 5 feet.
Floor bounce is usually in the area of 200Hz, but that varies with geometry.
Here is a calculator to help: Floor/Ceiling Reflection Calculator
And more info:
SBIR calculator
audio blog: A little more into boundary conditions
Floor bounce makes notches in the response. Having thick padded carpet will be a big help at mid and high frequencies, less help down low because of the wavelengths involved. At 220 Hz that's 5 feet.
Horbach-Keele solves the floor reflection issue
There is only one clean and effective solution against floor reflection: The Horbach-Keele Topology, as mentionned elswhere in this context and forum. It works also with open baffles, but is neither fast, nor inexpensive. So it's slightly off-topic to mention it here. But it works, and it works elegantly: You "just" have to tailor the null of the array's vertical polar into the angle of the floor reflection. As a consequence, null will be reflected ... And so logically, Null perturbs the on-axis response, and so null dip will occur. And this also goes for a concrete floor - no carpets needed. It's not only theory - I have verified this neat behavior of Horbach Keele's with a functional prototype. So, as a consequence along with a fast and inexpensive OB, you will have to live with the floor reflection. No free lunch.
There is only one clean and effective solution against floor reflection: The Horbach-Keele Topology, as mentionned elswhere in this context and forum. It works also with open baffles, but is neither fast, nor inexpensive. So it's slightly off-topic to mention it here. But it works, and it works elegantly: You "just" have to tailor the null of the array's vertical polar into the angle of the floor reflection. As a consequence, null will be reflected ... And so logically, Null perturbs the on-axis response, and so null dip will occur. And this also goes for a concrete floor - no carpets needed. It's not only theory - I have verified this neat behavior of Horbach Keele's with a functional prototype. So, as a consequence along with a fast and inexpensive OB, you will have to live with the floor reflection. No free lunch.
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What's been missed in all of this (and I apologize) is that the small Manzie is made to sit on a speaker stand. Sitting on the stand the speaker is well up at listening height.
You could build wings that go all the way to the floor instead of speaker stands, leaving an open space. That's been discussed a few times somewhere in the thread. Of course you can go all the way to the floor with the baffle, but that is going to change the woofer response and require some crossover tweaks.
My suggestion would be to make the lower baffle removable. That way you can test the speaker as designed (in the air) and with the baffle to the floor.
Who's the ugly guy with the beard?
Time to add a few design comments.... Most and or all of what I am going to add here has been discussed before. During early Manzanita baffle design experiments, crude measurements along with extensive listening sessions indicated a couple of things that needed addressed. Floor reflection(s) was one of them. Initially started out with a floor standing, 40" tall x 14" wide baffle. No wings. Woofer close to the floor. Tweeter about 34" off the floor to get it close to ear level for a seated listener. Once I flattened the bass output with zobel and large inductor the bass at a 8-10' listening distance was a bit weak and quite lumpy. Notice when I measured again with the baffle 24" or so off the floor, the lumps smoothed out quite a bit. Played with card board wings of various shapes and depths trying to obtain more bass extension with out adding cavity resonances.
In keeping with KISS, wanted the baffle to be as small and light-weight as possible. Easy to fabricate from inexpensive, readily available low cost materials. So evolved the stand mounted original Manzanita. The revised design target morphed into building a speaker that was roughly the size of the larger bookshelf offerings of the 60's- mid 80's. The mid - tweet upgrade to the Vifa TC9 3.5" full range completed that goal. Large woofer two way not that much larger than say the original Large Advent in terms of baffle dimensions. Bass extension and efficiency are similar when both are operated on a stand and out a way from a rear wall where both designs offer the best tonal balance.
One more thing.... the larger Ultra woofer location is more or less the same in terms of height above the floor. So you can do a floor mounted version, but floor bounce will be a bit more than the stand mounted version. And the woofer will be a bit more efficient, so the tweeter pad resistor is an ohm or two lower for most listener tastes. The high pass cap may need to be trimmed a bit too in order to retain the intended crossover point.
Time to add a few design comments.... Most and or all of what I am going to add here has been discussed before. During early Manzanita baffle design experiments, crude measurements along with extensive listening sessions indicated a couple of things that needed addressed. Floor reflection(s) was one of them. Initially started out with a floor standing, 40" tall x 14" wide baffle. No wings. Woofer close to the floor. Tweeter about 34" off the floor to get it close to ear level for a seated listener. Once I flattened the bass output with zobel and large inductor the bass at a 8-10' listening distance was a bit weak and quite lumpy. Notice when I measured again with the baffle 24" or so off the floor, the lumps smoothed out quite a bit. Played with card board wings of various shapes and depths trying to obtain more bass extension with out adding cavity resonances.
In keeping with KISS, wanted the baffle to be as small and light-weight as possible. Easy to fabricate from inexpensive, readily available low cost materials. So evolved the stand mounted original Manzanita. The revised design target morphed into building a speaker that was roughly the size of the larger bookshelf offerings of the 60's- mid 80's. The mid - tweet upgrade to the Vifa TC9 3.5" full range completed that goal. Large woofer two way not that much larger than say the original Large Advent in terms of baffle dimensions. Bass extension and efficiency are similar when both are operated on a stand and out a way from a rear wall where both designs offer the best tonal balance.
One more thing.... the larger Ultra woofer location is more or less the same in terms of height above the floor. So you can do a floor mounted version, but floor bounce will be a bit more than the stand mounted version. And the woofer will be a bit more efficient, so the tweeter pad resistor is an ohm or two lower for most listener tastes. The high pass cap may need to be trimmed a bit too in order to retain the intended crossover point.