burn-in testing - day 2:
Well I have the Mamboni Walsh5/Pioneer/Heil Version 1 Mod Zero alpha version test mule (say that three times fast!)
placed into the 1st listening slot. It is 2 ft. (61 cm) from the rear wall - 3ft (91 cm) from the side wall and separated from the AMT2 reference speaker by 9 ft. (274 cm) - my listening position #1 is 12 ft (3.6 m) away and centered between the two speakers and position # 2 is 10 ft. (3 m) distance and to the left of center by 3 ft. (1 m).
Today I let temptation get the better of me and did some fooling around with things - even though the Pioneer 10 inch is only about 3 hours old - couldn't help myslef!
The Mamboni unit is really kicking the AMT2's butt all over the place in terms of just about anything! But - yeah there are some but's - as always - there are some things that need a bit of tweaking - as always!
Bass response is "clean" and free of any signs of muddiness and seems quick enough to keep up with the Heil tweeter well into lower mid-range. The lower base response is tight but could use a bit more punch and I believe that to be my fault by using carpet in the inside of the Sonotube to damp the cardboard echo it had. On the next unit I will stuff with Acousta-Stuf to 1/2 full per Dr. Mamboni's original design - and damp the SonoTube wall on the outside with carpet. This very well could be key into fabricating a unit with a bit more kick in the lower base. My good friend BudP has also made some suggestions concerning mid frequency response that I will incorporate into the 2nd unit and report about.
It should be understood by all that this design does provide a responsive and clean bass but it does not provide sub-woofer performance - and it never will because it is not intended for that use. Those (like me) that want the lower octaves will need to use a proper (and quick) sub-woofer.
The mid-frequencies are rather good - even with a 3 hour old unit that most likely needs another good 80 to 100 hours to season. Not only is this (the 10 inch Pioneer) a brand new unit - it has the Mamboni triangles freshly applied and I suspect that between all of the speaker dope and felt that things will only get better with a bit of "stretching" from being worked in (or worked over
).
I am wondering about the placement height of the Pioneer because I notice that I get about a 3db (guessing by use of calibrated ear) of gain when I stand up (I'm 6 ft. tall) as to when I'm sitting. The mids sound fuller and richer as well. I know that mids are fuller by placing my ear near the speaker (about 1 ft. away) and then doing some deep knee bends to get myself below the speaker baffle which is horizontal in this case. When I slowly rise to a full standing position I can listen to Pioneer improve in fullness - and it starts getting "sweet" when I'm about 1 ft. above it (while still 1 ft. away). I'm thinking that on the 2nd test unit of chopping off about 6 inches in height of the SonoTube and playing with the rather wide baffle I used in this 1st test unit. I'm thinking that for the speaker baffle I will consider a stepped baffle that would resemble the stepped pyramids used by the Inca's and Mayan's - but it would only have two or three "steps" - I know I will use BudP's EnABL pattern around the edge of the baffle - but I'll do that after the 1st test is finished.
I have my Heil unit suspended above the rear port of the Pioneer speaker - The Pioneer is one of those that have a hole in the middle of the rear of the speaker for venting - and it's reflecting off of the bottom of the Heil tweeter. Mamboni's original design used a metal bracket to mount his tweeter with and that bracket helped to block the vent noise being radiated from the front of the speaker and this is worth some consideration. In the attached photo you can see where I have placed a damp sponge in front of the vent hole for testing purposes and it does help prevent the speaker vent from adding a bit of "clutter" to things.
The Heil units are "shinny" or "bright" with that added "sss" sound often presented by the whizzer cone on my Fostex 167's (or any untreated whizzer cone for that matter). If I reduce the treble by using the tone control on the amp the "sss" goes away - but then so do a lot of other things - and the high end starts sounding rather dead and uninvolved.
Seeing as how I can't whip on one of Dave's (Planet10) phase plugs on the Heils I believe that a BudP EnABL pattern placed just next to the diaphragm inner and outer edges of the magnet flange will be worth a try. Yeah I know that the flange next to the diaphragm dose not flex like a speaker cone - but BudP's pattern will also work on fixed surfaces like speaker baffles - so I'm sure that it will provide some benefits here. I'll just need to make it a bit 3 dimensional by using a thick paint - say about 3-5 mills worth.
Well - That was a bit of a long post - especially for just a bit of fooling around today - not even really testing yet - but I thought I would share what I've learned to date for those of you that are looking at building a set of these speakers.
Are they good?
When I came in from running errands this morning my wife was playing "ABBA" and dancing with her dachshund and having a blast!
It would not be polite (or wise ) to reveal my wife's age. I will tell you that she is a Grandmother and has a 35 year old son.
I will give her a new American Indian name - and I am part (small part) American Indian - I will now call her "Dances with Dachshunds".
There are not a whole lot of speakers in the world that are musical enough to get a Grand Mama up and dancing with her dog. That vision alone is worth the price of admission!
Well I have the Mamboni Walsh5/Pioneer/Heil Version 1 Mod Zero alpha version test mule (say that three times fast!)
placed into the 1st listening slot. It is 2 ft. (61 cm) from the rear wall - 3ft (91 cm) from the side wall and separated from the AMT2 reference speaker by 9 ft. (274 cm) - my listening position #1 is 12 ft (3.6 m) away and centered between the two speakers and position # 2 is 10 ft. (3 m) distance and to the left of center by 3 ft. (1 m). Today I let temptation get the better of me and did some fooling around with things - even though the Pioneer 10 inch is only about 3 hours old - couldn't help myslef!
The Mamboni unit is really kicking the AMT2's butt all over the place in terms of just about anything! But - yeah there are some but's - as always - there are some things that need a bit of tweaking - as always!
Bass response is "clean" and free of any signs of muddiness and seems quick enough to keep up with the Heil tweeter well into lower mid-range. The lower base response is tight but could use a bit more punch and I believe that to be my fault by using carpet in the inside of the Sonotube to damp the cardboard echo it had. On the next unit I will stuff with Acousta-Stuf to 1/2 full per Dr. Mamboni's original design - and damp the SonoTube wall on the outside with carpet. This very well could be key into fabricating a unit with a bit more kick in the lower base. My good friend BudP has also made some suggestions concerning mid frequency response that I will incorporate into the 2nd unit and report about. It should be understood by all that this design does provide a responsive and clean bass but it does not provide sub-woofer performance - and it never will because it is not intended for that use. Those (like me) that want the lower octaves will need to use a proper (and quick) sub-woofer.
The mid-frequencies are rather good - even with a 3 hour old unit that most likely needs another good 80 to 100 hours to season. Not only is this (the 10 inch Pioneer) a brand new unit - it has the Mamboni triangles freshly applied and I suspect that between all of the speaker dope and felt that things will only get better with a bit of "stretching" from being worked in (or worked over
).I am wondering about the placement height of the Pioneer because I notice that I get about a 3db (guessing by use of calibrated ear) of gain when I stand up (I'm 6 ft. tall) as to when I'm sitting. The mids sound fuller and richer as well. I know that mids are fuller by placing my ear near the speaker (about 1 ft. away) and then doing some deep knee bends to get myself below the speaker baffle which is horizontal in this case. When I slowly rise to a full standing position I can listen to Pioneer improve in fullness - and it starts getting "sweet" when I'm about 1 ft. above it (while still 1 ft. away). I'm thinking that on the 2nd test unit of chopping off about 6 inches in height of the SonoTube and playing with the rather wide baffle I used in this 1st test unit. I'm thinking that for the speaker baffle I will consider a stepped baffle that would resemble the stepped pyramids used by the Inca's and Mayan's - but it would only have two or three "steps" - I know I will use BudP's EnABL pattern around the edge of the baffle - but I'll do that after the 1st test is finished.
I have my Heil unit suspended above the rear port of the Pioneer speaker - The Pioneer is one of those that have a hole in the middle of the rear of the speaker for venting - and it's reflecting off of the bottom of the Heil tweeter. Mamboni's original design used a metal bracket to mount his tweeter with and that bracket helped to block the vent noise being radiated from the front of the speaker and this is worth some consideration. In the attached photo you can see where I have placed a damp sponge in front of the vent hole for testing purposes and it does help prevent the speaker vent from adding a bit of "clutter" to things.
The Heil units are "shinny" or "bright" with that added "sss" sound often presented by the whizzer cone on my Fostex 167's (or any untreated whizzer cone for that matter). If I reduce the treble by using the tone control on the amp the "sss" goes away - but then so do a lot of other things - and the high end starts sounding rather dead and uninvolved.
Seeing as how I can't whip on one of Dave's (Planet10) phase plugs on the Heils I believe that a BudP EnABL pattern placed just next to the diaphragm inner and outer edges of the magnet flange will be worth a try. Yeah I know that the flange next to the diaphragm dose not flex like a speaker cone - but BudP's pattern will also work on fixed surfaces like speaker baffles - so I'm sure that it will provide some benefits here. I'll just need to make it a bit 3 dimensional by using a thick paint - say about 3-5 mills worth. Well - That was a bit of a long post - especially for just a bit of fooling around today - not even really testing yet - but I thought I would share what I've learned to date for those of you that are looking at building a set of these speakers.
Are they good?
When I came in from running errands this morning my wife was playing "ABBA" and dancing with her dachshund and having a blast!
It would not be polite (or wise
) to reveal my wife's age. I will tell you that she is a Grandmother and has a 35 year old son.I will give her a new American Indian name - and I am part (small part) American Indian - I will now call her "Dances with Dachshunds".
There are not a whole lot of speakers in the world that are musical enough to get a Grand Mama up and dancing with her dog. That vision alone is worth the price of admission!
Greg,
Interesting link, thanks. I suspect they would work well with Mamboni's process, if we could devise a way to embed them into the cone or in a material that has the same properties as the glue he uses.
Would be neat to mold them into the cone mix and be able to etch them free in just the areas you wanted them. Pipe dreams for sure.
Not sure they would work for EnABL though. It is a process of exclusion and impedance, though the fibers might help somewhat in getting more energy off of the boundary layer, right at the beginning of the EnABL process.
Never the less, something to let simmer for a bit and see what rises to the surface.
Bud
Interesting link, thanks. I suspect they would work well with Mamboni's process, if we could devise a way to embed them into the cone or in a material that has the same properties as the glue he uses.
Would be neat to mold them into the cone mix and be able to etch them free in just the areas you wanted them. Pipe dreams for sure.
Not sure they would work for EnABL though. It is a process of exclusion and impedance, though the fibers might help somewhat in getting more energy off of the boundary layer, right at the beginning of the EnABL process.
Never the less, something to let simmer for a bit and see what rises to the surface.
Bud
EnABL application technique?
Hi Bud, I've enjoyed your posts greatly. I had an idea for a simple method of applying the EnABL pattern: make a simple paint roller. Use a short length of dowel, say 25-40mm diameter and similar length or thereabouts, depending on the pattern size, and attach porous raised rectangles made from thin adhesive foam tape to the roller as per the pattern. The paint can be applied to the foam and then the roller used to apply the pattern to the surface in question. Hope I've made my description clear, do you think it would work?
Best regards,
Mike Spence
Hi Bud, I've enjoyed your posts greatly. I had an idea for a simple method of applying the EnABL pattern: make a simple paint roller. Use a short length of dowel, say 25-40mm diameter and similar length or thereabouts, depending on the pattern size, and attach porous raised rectangles made from thin adhesive foam tape to the roller as per the pattern. The paint can be applied to the foam and then the roller used to apply the pattern to the surface in question. Hope I've made my description clear, do you think it would work?
Best regards,
Mike Spence
Hi Mike,
I think it would definitely work for cabinet surfaces, baffles used in dipole set ups and any other surface where the blocks in two rows were the same size. You might have to add a rubber O ring to make drive contact, off to one side, just to ensure that the roller turned. Paint might not always provide enough "sticktion" to keep the roller from smearing a block.
For angled, curved, cones, the problem will be more difficult, but I think the idea is sound. Take a look back through these pages until you come across an unrolled conic section, down load it, print it, cut it out and tape it back up into a cone to begin to see the difficulties you would face. Not overwhelming if you are clever in solid geometry.
I suspect you would have to turn a dowel down to match the cone's swept diameter difference, between the top and bottom of a row. Still you might actually be able to print both rows of blocks at one time, if you were a lot more clever than I am.
Bud
I think it would definitely work for cabinet surfaces, baffles used in dipole set ups and any other surface where the blocks in two rows were the same size. You might have to add a rubber O ring to make drive contact, off to one side, just to ensure that the roller turned. Paint might not always provide enough "sticktion" to keep the roller from smearing a block.
For angled, curved, cones, the problem will be more difficult, but I think the idea is sound. Take a look back through these pages until you come across an unrolled conic section, down load it, print it, cut it out and tape it back up into a cone to begin to see the difficulties you would face. Not overwhelming if you are clever in solid geometry.
I suspect you would have to turn a dowel down to match the cone's swept diameter difference, between the top and bottom of a row. Still you might actually be able to print both rows of blocks at one time, if you were a lot more clever than I am.
Bud
I have discovered a new edge treatment for the speaker surround - and I strongly recommend that others do not attempt it! 
I decided to install some longer screws into the speaker frame to insure that it was well sealed against the baffle. I was fairly sure that it was - but I was also aware that the screws I used were just short enough to be in question - and I wanted to eliminate them as a possible source for air leakage. As I was backing them out of the speaker I noticed some sticky black rubber adhering to the screw threads and I figured it was some of the black silicone glue I had used to secure the gasket to the baffle - but alas - that was not to be.
Once I had the speaker removed it became apparent that the "sticky black rubber" was in fact the butyl rubber surround of the speaker - and it was now in need of a new surround.
So a word of caution - trim that little piece of black rubber material away from the screw hole used for mounting the speaker to the baffle. When front mounting a speaker this usually is not a problem - but driving the screws in from the back side of the speaker will "grab" the rubber surround - and - and - sob - sob - I just can't stand to go on and say the unmentionable
Good for me I have a second speaker with the Mamboni triangles applied! Good for me that I also have another spare speaker to mod. Plus - on the bright side - I'll to learn how to repair a speaker surround!! OH BOY!! - Just shoot me and get it over with!!
I decided to install some longer screws into the speaker frame to insure that it was well sealed against the baffle. I was fairly sure that it was - but I was also aware that the screws I used were just short enough to be in question - and I wanted to eliminate them as a possible source for air leakage. As I was backing them out of the speaker I noticed some sticky black rubber adhering to the screw threads and I figured it was some of the black silicone glue I had used to secure the gasket to the baffle - but alas - that was not to be.
Once I had the speaker removed it became apparent that the "sticky black rubber" was in fact the butyl rubber surround of the speaker - and it was now in need of a new surround.
So a word of caution - trim that little piece of black rubber material away from the screw hole used for mounting the speaker to the baffle. When front mounting a speaker this usually is not a problem - but driving the screws in from the back side of the speaker will "grab" the rubber surround - and - and - sob - sob - I just can't stand to go on and say the unmentionable
Good for me I have a second speaker with the Mamboni triangles applied! Good for me that I also have another spare speaker to mod. Plus - on the bright side - I'll to learn how to repair a speaker surround!! OH BOY!! - Just shoot me and get it over with!!
Thomas,
Sorry to hear of your accident. As they say now...IT happens. I wonder if you might like to take this opportunity and try an experiment with what is left. It seems to me that using the speaker face down as you are now that dome which covers and keeps dirt out of the voicecoil gap does nothing helpful for you. It creates a resonant chamber and the material it is made of adds mass, hurting the HF resonse of the cone. Why not carefully remove it and give it another audition. Actually from what I see of your surround damage I think you can fix that with some soft glue and the repair will not be seen when it is mounted. I just successfully repaired a large tear in a foam rubber roll surround on a 1 inch P-P excursion 12 inch sub using Goop.
Sorry to hear of your accident. As they say now...IT happens. I wonder if you might like to take this opportunity and try an experiment with what is left. It seems to me that using the speaker face down as you are now that dome which covers and keeps dirt out of the voicecoil gap does nothing helpful for you. It creates a resonant chamber and the material it is made of adds mass, hurting the HF resonse of the cone. Why not carefully remove it and give it another audition. Actually from what I see of your surround damage I think you can fix that with some soft glue and the repair will not be seen when it is mounted. I just successfully repaired a large tear in a foam rubber roll surround on a 1 inch P-P excursion 12 inch sub using Goop.
C2C,
If the surround is not actually torn, just messed with, you do not have to do anything. If the Goop doesn't appeal you can go on safari to the big city and go to a dive products store and purchase a small tube of foam gasket repair material. Or, possibly the glue used to repair tears in dive suits. We used to repair the occasional screw driver hole in surrounds with the real PVA compound which never quite set up hard. But then we were also coating the entire cone and surround in PVA , which is a reasonably viable alternative to the Mamaboni and EnABL process. Will provide maybe 70% of our control over ringing and spurious refractions. Of course, you can only buy the stuff in 10 gallon buckets, but maybe your neighbors would like their various surfaces painted too.......
If you want to stick the thing back down use Elmers White Glue. It is not pure PVA (Poly Vynil Acrylic... I think) but it is close enough and PVA is the surround and spider glue, to basket, of choice. Surround to paper cone is a different story and it will be easier on your store of blue language to just go looking for a replacement cone with surround and voice coil from an authorized dealer/repair shop, buy a plastic shim stock kit from McMaster Carr to align the new cone and voice coil in to the gap with, preattach a new spider with two part black epoxy they sell you from the dealer/ repair shop, by sliding the coil into the gap with shim stock just to the point where the surround touches the basket and then glue the spider with the epoxy and wait a day, before gluing anything else, and then putting runny PVA on spider and surround mounting surfaces and, while carefully holding on to the plastic shims, wound into the voice coil, slide the whole apparatus down just far enough to make contact between surround and basket and spider and basket........ .......just buy another driver if you can't repair the surround... lot's easier on your heart.
Bud
If the surround is not actually torn, just messed with, you do not have to do anything. If the Goop doesn't appeal you can go on safari to the big city and go to a dive products store and purchase a small tube of foam gasket repair material. Or, possibly the glue used to repair tears in dive suits. We used to repair the occasional screw driver hole in surrounds with the real PVA compound which never quite set up hard. But then we were also coating the entire cone and surround in PVA , which is a reasonably viable alternative to the Mamaboni and EnABL process. Will provide maybe 70% of our control over ringing and spurious refractions. Of course, you can only buy the stuff in 10 gallon buckets, but maybe your neighbors would like their various surfaces painted too.......
If you want to stick the thing back down use Elmers White Glue. It is not pure PVA (Poly Vynil Acrylic... I think) but it is close enough and PVA is the surround and spider glue, to basket, of choice. Surround to paper cone is a different story and it will be easier on your store of blue language to just go looking for a replacement cone with surround and voice coil from an authorized dealer/repair shop, buy a plastic shim stock kit from McMaster Carr to align the new cone and voice coil in to the gap with, preattach a new spider with two part black epoxy they sell you from the dealer/ repair shop, by sliding the coil into the gap with shim stock just to the point where the surround touches the basket and then glue the spider with the epoxy and wait a day, before gluing anything else, and then putting runny PVA on spider and surround mounting surfaces and, while carefully holding on to the plastic shims, wound into the voice coil, slide the whole apparatus down just far enough to make contact between surround and basket and spider and basket........ .......just buy another driver if you can't repair the surround... lot's easier on your heart.
Bud
Hi rcavictim
- thank you for your post and suggestions.
I have installed the 2nd test speaker and while I was at it yanked out the carpet I had lined the walls of the SonoTube with and filled it half full of Acousta-Stuf packed to a "medium" (calibrated by guess) density. I also soldered in another 4 ohm 10 watt resistor (total of 8 ohm's now for those who are keeping count) in series with the Heil tweeter to trim it back a bit.
Your point about the rear vent of the Pioneer being open and facing up to collect lord only know what (spiders, dust, roof plaster
) is well taken and I'll go slap a piece of felt over it for the testing phase. The dome of the Pioneer has a 3/4 in hole cut into the center of it per Mamboni's design and the felt is being used as a vaiovent type of port. BTW - with the amount of air it forces out of the vent I might not need to worry very much because it is exhausting a good amount of air from that vent!! No "chug chug" sounds tho.
I have already ordered a surround repair kit for Simply Speakers - alway good to have one on hand. I repaired quite a few back in my stereo repair days - but that was like 30 years ago - back when we used the canvas off of old sailing ships if we couldn't get any buffalo hide.
A patch might well do the job - need to find some thin rubber - perhaps one of those bicycle inner tube repair kits would work 
The speaker is back into burn-in and playing just fine - so just a slight delay. I'm also going to knock together a unit with the Pioneer facing upwards as you have suggested - Very similar in concept to the speakers the folks at Oscar Heil Speakers are showing off in the photo.
- thank you for your post and suggestions.
I have installed the 2nd test speaker and while I was at it yanked out the carpet I had lined the walls of the SonoTube with and filled it half full of Acousta-Stuf packed to a "medium" (calibrated by guess) density. I also soldered in another 4 ohm 10 watt resistor (total of 8 ohm's now for those who are keeping count
) in series with the Heil tweeter to trim it back a bit.Your point about the rear vent of the Pioneer being open and facing up to collect lord only know what (spiders, dust, roof plaster
) is well taken and I'll go slap a piece of felt over it for the testing phase. The dome of the Pioneer has a 3/4 in hole cut into the center of it per Mamboni's design and the felt is being used as a vaiovent type of port. BTW - with the amount of air it forces out of the vent I might not need to worry very much because it is exhausting a good amount of air from that vent!! No "chug chug" sounds tho. I have already ordered a surround repair kit for Simply Speakers - alway good to have one on hand. I repaired quite a few back in my stereo repair days - but that was like 30 years ago - back when we used the canvas off of old sailing ships if we couldn't get any buffalo hide.
A patch might well do the job - need to find some thin rubber - perhaps one of those bicycle inner tube repair kits would work The speaker is back into burn-in and playing just fine - so just a slight delay. I'm also going to knock together a unit with the Pioneer facing upwards as you have suggested - Very similar in concept to the speakers the folks at Oscar Heil Speakers are showing off in the photo.
Hi BudP,
Good to hear from ya buddy!
There are two good sized tears in the edge of the surround - so some type of patch is in order. I think I'll try a thin rubber patch similar to repairing an inner tube - should be OK - I think
If not then it's surround repair time - which the last time I did one was a bunch easier than a cone replacement. Just carefully remove the existing surround and glue on the new one - trim it up a bit and glue the new surround to the speaker frame being careful about fit and tension - and not getting glue all over everything!
BTW - yanking out the carpet and replacing it with the Acousta-Stuf was a break even - pretty much no difference. I might need to take out a little tho - the bass seems a little weak.
Good to hear from ya buddy!
There are two good sized tears in the edge of the surround - so some type of patch is in order. I think I'll try a thin rubber patch similar to repairing an inner tube - should be OK - I think
If not then it's surround repair time - which the last time I did one was a bunch easier than a cone replacement. Just carefully remove the existing surround and glue on the new one - trim it up a bit and glue the new surround to the speaker frame being careful about fit and tension - and not getting glue all over everything!
BTW - yanking out the carpet and replacing it with the Acousta-Stuf was a break even - pretty much no difference. I might need to take out a little tho - the bass seems a little weak.
Thomas,
There appears to be confusion referring to the front and rear of a speaker because of the way you are using it...backwards. To me, regardless of use, the back is the side the magnet sticks out OK ?
I was not suggesting you use the speaker with the front (concave side of cone) facing upwards. As a bending wave Walsh type transducer you have it facing down into the cabinet. I meant to leave that alone. I merely suggested the dome in the middle of the cone front is not helping you now and it might be better gone. I saw that you had punched a hole in it and added felt as a variovent. I did not comment about plugging the vent hole through the magnet center pole piece. With the dome removed from the front there will be no piston action to move cooling air through the hole in the pole piece so even a solid plug could be applied otherwise at the rear of the magnet or you will have another port into the airspace below the speaker diaphragm into the bass cabinet. If left open I suppose you could levitate a ping pong ball over it with a good loud bass note from a sine generator, the same way a beach ball can be levitated above a blowing vacuum cleaner nozzle. If the bass cabinet has a port as in bass reflex perhaps not.
There appears to be confusion referring to the front and rear of a speaker because of the way you are using it...backwards. To me, regardless of use, the back is the side the magnet sticks out OK ?
I was not suggesting you use the speaker with the front (concave side of cone) facing upwards. As a bending wave Walsh type transducer you have it facing down into the cabinet. I meant to leave that alone. I merely suggested the dome in the middle of the cone front is not helping you now and it might be better gone. I saw that you had punched a hole in it and added felt as a variovent. I did not comment about plugging the vent hole through the magnet center pole piece. With the dome removed from the front there will be no piston action to move cooling air through the hole in the pole piece so even a solid plug could be applied otherwise at the rear of the magnet or you will have another port into the airspace below the speaker diaphragm into the bass cabinet. If left open I suppose you could levitate a ping pong ball over it with a good loud bass note from a sine generator, the same way a beach ball can be levitated above a blowing vacuum cleaner nozzle. If the bass cabinet has a port as in bass reflex perhaps not.
Hi Bob,
Thank you for clarifying - but I still want to try the Oscar Heil configuration with the cone facing upwards as well - just to see what it sounds like. I still have an untreated Pioneer to use in that manner - although I'll put BudP's EnABL pattern on it and leave the dome intact. It does mean that I may need to port the enclosure tho - but I'll go with a sealed version 1st.
Just doing what all good DIYer's do - fooling around with stuff!!
Thank you for clarifying - but I still want to try the Oscar Heil configuration with the cone facing upwards as well - just to see what it sounds like. I still have an untreated Pioneer to use in that manner - although I'll put BudP's EnABL pattern on it and leave the dome intact. It does mean that I may need to port the enclosure tho - but I'll go with a sealed version 1st.
Just doing what all good DIYer's do - fooling around with stuff!!
c2cthomas said:Hi Bob,
Thank you for clarifying - but I still want to try the Oscar Heil configuration with the cone facing upwards as well - just to see what it sounds like. I still have an untreated Pioneer to use in that manner - although I'll put BudP's EnABL pattern on it and leave the dome intact. It does mean that I may need to port the enclosure tho - but I'll go with a sealed version 1st.
Just doing what all good DIYer's do - fooling around with stuff!!
Ah yes the `ol Oscar Heil configuration. If you want to dink around you could also try the Oscar Meyer configuration. Ha ha.
You know. Dink/weiner.
Sorry. 
Hey it`s Friday the 13th.
Listening test of the Mamboni Walsh 5 Remakes -
This is a preliminary review of my build of Mamboni's Walsh5 remakes. My version is using a Heil AMT tweeter vs. Mamboni's dome tweeter but most other things follow his design.
As it stands right now I've only just installed a fresh Pioneer 10 inch mid-woofer atop my SonoTube base and I'll let it break in for 80 to 100 hours before getting down to some serious listening and adding some other tweaks. So this review is more of a first impression rather than the "full monty".
The first speaker to be compared with was this speakers original mate - a vintage ESS AMT2 purchased on eBay - one of which was munched by being dropped by the local delivery guy in the brown truck. I purchased the pair just for old times sake as I once lived in Sacramento Calif. where they were made and knew some of the guys that worked for ESS. The AMT 2's were never regarded as a "great" speaker - but they were ahead of their time and performed to a fairly decent level on the mid to high frequencies due to the Heil AMT tweeter. Most people that wanted some improvement in their fidelity would usually wind up reworking the xovers and putting in a decent woofer - and sometimes just taking the Heil and putting it on top of a well designed enclosure. That is pretty much what I had in mind when I discovered this thread and said to myself - "self - using a Heil tweeter with a Walsh like driver could be a bunch of fun".
Note: this Pioneer driver as modified by Mamboni isn't a true "Walsh driver" but it does have similar performance due to his felt triangles - see earlier post in this thread.
The Mamboni design - along with his triangles (which I call "Mamboni Magic" ) simply leaves the AMT2's so far in the dust that you'll need radar to find 'em! 
With no "box" to smear, distort, color, or otherwise mess with what the speaker cone is doing these speakers have an openness that I find pleasant and musical. Doing the A-B switching thing isn't fun for very long - sort of like watching your favorite team getting badly beat with only seconds left on the game clock.
The Pioneer 10 inch is fairly quick mid-bass unit that keeps up well with the Heil tweeter. There are better bass units (a bunch) around that do bass - but I haven't found any 10 inch woofers that will get up to 6k hz midrange as Mamboni uses in his design. The Heil AMT does a nice job on the top end - but you could use just about any decent tweeter and get good results with this design.
I soon tired of playing with the ESS unit (poor guy - future parts source for my next tweeter - the rest is scrap), and decided to A-B with my Fostex 167 full range monitors. No crossovers in these guys and I use them as a "base" with which to compare other speakers. These units are fairly good at what they do - and when mated with my sub-woofer perform well - I would rate them around a 7.5 to 8 on 10 scale. They did better than the AMT2's - but they still pretty much took 2nd place to the Mamboni design. Again - it's the "box" that cost them the contest - which took all of 5 minutes to conduct.
The Mamboni design - with all the speaker surfaces exposed directly to the open air - and not being constrained by an enclosure - offer a somewhat OB openness of sound and the Mamboni triangles do indeed seem to work on the Pioneer to keep it controlled and smooth.
I still have some things to look into concerning this design - such as BudP's EnABLE pattern - but I'm happy with the early results on what is little more than a raw test unit that is not fully broke in - let alone tweaked. I can't wait to finish building up the 2nd test unit. After playing around with things for awhile I'll settle in on a final design for my personal use and which I am sure will be a fine performing speaker. Will it be the best speaker ever made? That entirely depends on your taste in speakers.
One thing is for sure. For the cost involved ($200 - $400 for the pair - depending on selection of tweeters and finish) , the ease of construction, and the very sweet and open sound these speakers produce - it won't kill - but will seriously wound - the giants that cost one hell of a lot more. In fact it will slay quite a few of them IMHO.
This is a preliminary review of my build of Mamboni's Walsh5 remakes. My version is using a Heil AMT tweeter vs. Mamboni's dome tweeter but most other things follow his design.
As it stands right now I've only just installed a fresh Pioneer 10 inch mid-woofer atop my SonoTube base and I'll let it break in for 80 to 100 hours before getting down to some serious listening and adding some other tweaks. So this review is more of a first impression rather than the "full monty".
The first speaker to be compared with was this speakers original mate - a vintage ESS AMT2 purchased on eBay - one of which was munched by being dropped by the local delivery guy in the brown truck. I purchased the pair just for old times sake as I once lived in Sacramento Calif. where they were made and knew some of the guys that worked for ESS. The AMT 2's were never regarded as a "great" speaker - but they were ahead of their time and performed to a fairly decent level on the mid to high frequencies due to the Heil AMT tweeter. Most people that wanted some improvement in their fidelity would usually wind up reworking the xovers and putting in a decent woofer - and sometimes just taking the Heil and putting it on top of a well designed enclosure. That is pretty much what I had in mind when I discovered this thread and said to myself - "self - using a Heil tweeter with a Walsh like driver could be a bunch of fun".
Note: this Pioneer driver as modified by Mamboni isn't a true "Walsh driver" but it does have similar performance due to his felt triangles - see earlier post in this thread.
The Mamboni design - along with his triangles (which I call "Mamboni Magic"
) simply leaves the AMT2's so far in the dust that you'll need radar to find 'em! With no "box" to smear, distort, color, or otherwise mess with what the speaker cone is doing these speakers have an openness that I find pleasant and musical. Doing the A-B switching thing isn't fun for very long - sort of like watching your favorite team getting badly beat with only seconds left on the game clock.
The Pioneer 10 inch is fairly quick mid-bass unit that keeps up well with the Heil tweeter. There are better bass units (a bunch) around that do bass - but I haven't found any 10 inch woofers that will get up to 6k hz midrange as Mamboni uses in his design. The Heil AMT does a nice job on the top end - but you could use just about any decent tweeter and get good results with this design.
I soon tired of playing with the ESS unit (poor guy - future parts source for my next tweeter - the rest is scrap), and decided to A-B with my Fostex 167 full range monitors. No crossovers in these guys and I use them as a "base" with which to compare other speakers. These units are fairly good at what they do - and when mated with my sub-woofer perform well - I would rate them around a 7.5 to 8 on 10 scale. They did better than the AMT2's - but they still pretty much took 2nd place to the Mamboni design. Again - it's the "box" that cost them the contest - which took all of 5 minutes to conduct.
The Mamboni design - with all the speaker surfaces exposed directly to the open air - and not being constrained by an enclosure - offer a somewhat OB openness of sound and the Mamboni triangles do indeed seem to work on the Pioneer to keep it controlled and smooth.
I still have some things to look into concerning this design - such as BudP's EnABLE pattern - but I'm happy with the early results on what is little more than a raw test unit that is not fully broke in - let alone tweaked. I can't wait to finish building up the 2nd test unit. After playing around with things for awhile I'll settle in on a final design for my personal use and which I am sure will be a fine performing speaker. Will it be the best speaker ever made? That entirely depends on your taste in speakers.
One thing is for sure. For the cost involved ($200 - $400 for the pair - depending on selection of tweeters and finish) , the ease of construction, and the very sweet and open sound these speakers produce - it won't kill - but will seriously wound - the giants that cost one hell of a lot more. In fact it will slay quite a few of them IMHO.
Hi Bob!
1600 lbs I would not want to be the one to haul that load into the shop!! If we were closer I would of lent you the use of my Explorer.
At least you didn't wind up running into anything (it's hard to stop with that much weight on-board) and getting smushed up against the dash!
I was under the impression that 1600 lbs US is 725 kilo's CAN - how much is that in British Sterling?
I thought you folks north of the border were getting some nasty weather - no fun driving in that! One of the reasons I moved from Mass. to Calif.
1600 lbs
I would not want to be the one to haul that load into the shop!! If we were closer I would of lent you the use of my Explorer. At least you didn't wind up running into anything (it's hard to stop with that much weight on-board) and getting smushed up against the dash!
I was under the impression that 1600 lbs US is 725 kilo's CAN - how much is that in British Sterling?
I thought you folks north of the border were getting some nasty weather - no fun driving in that! One of the reasons I moved from Mass. to Calif.
Those 105AH, 12 volt batteries weigh 100 lbs each. That took the last of what energy I had for the day. I had help to load them but not to unload. Stuffed in every space available and on the seats trying to best distribute the load. This was my second trip of four expected. Good haul. I am building an E-motorcycle with four of them which ought to get me to town on windpower someday. I`m having fun learning PWM control and power MOSFETs right now as I try to make a DC traction motor speed controller. The rest of these batteries (about 60) will store and deliver alternate energy for the estate. storing wind power and electricity from WVO and whatever. Years of collecting bits and pieces here and there and building generators and stuff to eventually get off the grid.
Yes, would not want to have to stop or manouver quickly. The laws of physics are quite inflexible!
At $300 or so per battery new cost (X 64) that would have been quite a few pounds sterling. Fortunately my price was much more affordable. I was told they still have about 1/2 life left in them. Enough to run my 805 SET tube amp.
For content requirement, has anyone thought of trying to make a driver like the Ohm-A by making an aluminum cone from offset printing aluminum sheet? That stuff is pretty thin and a hard stiff alloy. I have some here I thought I might try if I can find a couple of suitable drivers (like 10 inch) to hack.
Yes, would not want to have to stop or manouver quickly. The laws of physics are quite inflexible!
At $300 or so per battery new cost (X 64) that would have been quite a few pounds sterling. Fortunately my price was much more affordable. I was told they still have about 1/2 life left in them. Enough to run my 805 SET tube amp.
For content requirement, has anyone thought of trying to make a driver like the Ohm-A by making an aluminum cone from offset printing aluminum sheet? That stuff is pretty thin and a hard stiff alloy. I have some here I thought I might try if I can find a couple of suitable drivers (like 10 inch) to hack.
Maybe with some help from this guy you could make it with paper.
http://www.diyaudio.com/forums/showthread.php?s=&threadid=99138 .
Personally, I am still happy with the Ciare HX201 facing the ceiling (just a little shout I have got used to).
http://www.diyaudio.com/forums/showthread.php?s=&threadid=99138 .
Personally, I am still happy with the Ciare HX201 facing the ceiling (just a little shout I have got used to).
quite a convergence of youthful ideas here...in spite of how old some of you claim to be.
I'm not as well versed,... have limited background in material sciences, dynamnics or acoustics,...so, some of this may be my imagination and can be dispensed with as such.
I'd like to raise my hand and ask from the back row:
What would the EnABL pattern for a cabinet edge look like?....it looks to me that the patterns applied to cones are symmetrical with respect to distance from the source...and perform some sort of "gating" or "combing" of the acoustic pressure waves.
Does the size necessarily change with distance from the source?
Do the blocks stay oriented with their long axis perpendicular to a line back to the source?
Would the use, as has been suggested, of a pattern on a mylar tape be conditioned or sensitized by the edge of the tape itself?
Some of the Mamboni discussion has regarded the effect on damping of the cone. The sound waves moving onto a stiffer baffle may benefit from treatment of the surround and frame of the speaker. The sound waves on the baffle have left that behind. I'm interested in learning more about the departure of the sound wave from the baffle. I think this is complicated by the compressibility of air...but wonder if there is a corrollary to the cavitation occurring off of a propeller in water....in that the amount and severity of diffraction is related to the abruptness of the departure. It seems there is a way being offerred here to "soften" that departure.
I'll sit down now
I'm not as well versed,... have limited background in material sciences, dynamnics or acoustics,...so, some of this may be my imagination and can be dispensed with as such.
I'd like to raise my hand and ask from the back row:
What would the EnABL pattern for a cabinet edge look like?....it looks to me that the patterns applied to cones are symmetrical with respect to distance from the source...and perform some sort of "gating" or "combing" of the acoustic pressure waves.
Does the size necessarily change with distance from the source?
Do the blocks stay oriented with their long axis perpendicular to a line back to the source?
Would the use, as has been suggested, of a pattern on a mylar tape be conditioned or sensitized by the edge of the tape itself?
Some of the Mamboni discussion has regarded the effect on damping of the cone. The sound waves moving onto a stiffer baffle may benefit from treatment of the surround and frame of the speaker. The sound waves on the baffle have left that behind. I'm interested in learning more about the departure of the sound wave from the baffle. I think this is complicated by the compressibility of air...but wonder if there is a corrollary to the cavitation occurring off of a propeller in water....in that the amount and severity of diffraction is related to the abruptness of the departure. It seems there is a way being offerred here to "soften" that departure.
I'll sit down now