lol, a speaker for a while ?
you mean like the same setup for over a week ?
I rearrange often, and after screwing with ambiophonics (maybe 7 years ago), the mids are recessed in a stereo triangle to my ears. So I stuck with 1 speaker mono ever since.
I received the philips full ranger 2 weeks ago.
Hooking it up sitting on the floor, listening off axis, it was nice.
I put the philips back in the box to protect it till October.
Going back to a 2khz 24db crossover reminded me of how a crossover may add detail, but it sounds less real, more like reproduced sound from a speaker.
me plan is this.
found here.
|| DHTRob - Tubeamplifiers and fullrange units: Several FullRange Philips units ||
Almost the same sized as the an15 on the baffle maybe around post 80.
67" tall, 16" wide center, and side panels 22.5" and 24.5".
1/2" birch ply outer layers with 1/2" thick sand between them.
I was up for 1/2" BB ply plus 1/2" corian or even mdf.
Norman
you mean like the same setup for over a week ?
I rearrange often, and after screwing with ambiophonics (maybe 7 years ago), the mids are recessed in a stereo triangle to my ears. So I stuck with 1 speaker mono ever since.
I received the philips full ranger 2 weeks ago.
Hooking it up sitting on the floor, listening off axis, it was nice.
I put the philips back in the box to protect it till October.
Going back to a 2khz 24db crossover reminded me of how a crossover may add detail, but it sounds less real, more like reproduced sound from a speaker.
me plan is this.
An externally hosted image should be here but it was not working when we last tested it.
found here.
|| DHTRob - Tubeamplifiers and fullrange units: Several FullRange Philips units ||
Almost the same sized as the an15 on the baffle maybe around post 80.
67" tall, 16" wide center, and side panels 22.5" and 24.5".
1/2" birch ply outer layers with 1/2" thick sand between them.
I was up for 1/2" BB ply plus 1/2" corian or even mdf.
Norman
well, I was on the fence thinking 3/4" BB ply and 3/4" mdf or corian just Thursday (or even 2 layers of 3/4" BB ply) to make things easier and quicker to construct.
Bamboo really will skyrocket the price.
I had a 5' tall (1/2" BB ply) with 12" wide center, and 15" and 19" wings (not deep enough, rolled @200hz). I had an 8" full range that made some James Taylor songs make the baffle sing (vibrate).
The original creator had sand, I use sand for resonance help (sandwich bags on horn throats or on speaker boxes), so that's what I'm using. Wharfdales had sand also I think. Ideally you mix stiff and soggy.
Go to 6:30, don't forget 480p
https://www.youtube.com/watch?v=gh9n9v4bNhY
Norman
Bamboo really will skyrocket the price.
I had a 5' tall (1/2" BB ply) with 12" wide center, and 15" and 19" wings (not deep enough, rolled @200hz). I had an 8" full range that made some James Taylor songs make the baffle sing (vibrate).
The original creator had sand, I use sand for resonance help (sandwich bags on horn throats or on speaker boxes), so that's what I'm using. Wharfdales had sand also I think. Ideally you mix stiff and soggy.
Go to 6:30, don't forget 480p
https://www.youtube.com/watch?v=gh9n9v4bNhY
Norman
Member
Joined 2009
Paid Member
My wife says it sounds 'kind of flat'.
So I took the back panel off the speaker. The sound has returned to something that sounds much nicer, more open, the bass has returned to what it was. Now it may be an uneven bass response with some mid-bass peaks, but it's quite clearly a better sound at the present time.
There are two things going on here.
With the back on it is a sealed cabinet (with some leaks perhaps) where I would expect to hear a flat frequency response with tight bass. But it sounds like a small desktop radio. This is much more than a missing mid-bass peakiness.
With the back off it also sounds more open and airy - this I assume, is the 'classic' open baffle sound. And it's nice. Would I design differently if intending it to be an open baffle from the start ? well the box shape is non-idea for open baffle but it provides a superbly stiff and stable platform for the driver, the top of the box is great for use as a hi-fi rack if your equipment is non-microphonic. In fact, there is a commercial speaker that has the same shape as the Big'un and is intended for use as an open baffle: http://www.6moons.com/audioreviews/yamamoto9/speaker_2.html
What's next ? - I think I need to get some materials to explore more of the Boffle concept with this enclosure.
On a separate note I have been reading Bud Purvine's thoughts about the AN15 driver. He loves it a lot. He recommends some simple treatments. The first is to put a little zig-glue on the back of the cone near the surround and on the back edge of the whizzer. I assume it is the viscoelestic properties of the glue that is important (it's a kind of glue that never dries). I don't have any of this glue in my neighbourhood so I smeared a little silicone on instead - it stays flexible and viscoelastic. I have noticed that the lower treble is not smoother and better tamed without any detrimental affects anywhere I can hear.
So I took the back panel off the speaker. The sound has returned to something that sounds much nicer, more open, the bass has returned to what it was. Now it may be an uneven bass response with some mid-bass peaks, but it's quite clearly a better sound at the present time.
There are two things going on here.
With the back on it is a sealed cabinet (with some leaks perhaps) where I would expect to hear a flat frequency response with tight bass. But it sounds like a small desktop radio. This is much more than a missing mid-bass peakiness.
With the back off it also sounds more open and airy - this I assume, is the 'classic' open baffle sound. And it's nice. Would I design differently if intending it to be an open baffle from the start ? well the box shape is non-idea for open baffle but it provides a superbly stiff and stable platform for the driver, the top of the box is great for use as a hi-fi rack if your equipment is non-microphonic. In fact, there is a commercial speaker that has the same shape as the Big'un and is intended for use as an open baffle: http://www.6moons.com/audioreviews/yamamoto9/speaker_2.html
What's next ? - I think I need to get some materials to explore more of the Boffle concept with this enclosure.
On a separate note I have been reading Bud Purvine's thoughts about the AN15 driver. He loves it a lot. He recommends some simple treatments. The first is to put a little zig-glue on the back of the cone near the surround and on the back edge of the whizzer. I assume it is the viscoelestic properties of the glue that is important (it's a kind of glue that never dries). I don't have any of this glue in my neighbourhood so I smeared a little silicone on instead - it stays flexible and viscoelastic. I have noticed that the lower treble is not smoother and better tamed without any detrimental affects anywhere I can hear.
Last edited:
Member
Joined 2009
Paid Member
correction: "I have noticed that the lower treble is smoother and better tamed without any detrimental affects anywhere I can hear."
Norman,
I did make a completely open, Open Baffle once which had the same size baffle as the Big'un and also a 15" driver: http://www.diyaudio.com/forums/full-range/174632-apollo-ob.html
But the Big'un has significantly better bass, so it seems that the sides of the box are helping out a lot with the sound - no doubt the longer path length for sound is the key factor.
Norman,
I did make a completely open, Open Baffle once which had the same size baffle as the Big'un and also a 15" driver: http://www.diyaudio.com/forums/full-range/174632-apollo-ob.html
But the Big'un has significantly better bass, so it seems that the sides of the box are helping out a lot with the sound - no doubt the longer path length for sound is the key factor.
yea, I can't believe the amount of people that can tolerate the "no bass" that a tiny baffle provides (not counting a floppy qts either).
Nice looking "apollo" project.
I'd prefer something looking that size but know I'd be bass disappointed (trying to run the driver down to 100hz).
2' from driver's edge to back of the any baffle, that's my minimum distance.
That's a +3 to +6db Feq hump around 140hz, really pleasurable compared to a sealed speaker without baffle step.
Then I can also cross at 100hz (about as high as my ears like).
I don't care what simulations say.
It will short circuit the shortest distance to the back side.
In your case, a deeper box may make some resonances you don't want. But trying stuffing like you are, you may get a nice compromise.
You can make a rectangle and snug it up against the back of your box. That way you don't have to rebuild a box. I like the box idea, it really prevents having a large "sound board" launching who knows what. That's why I'm going the sand filled sandwich route.
Norman
Nice looking "apollo" project.
I'd prefer something looking that size but know I'd be bass disappointed (trying to run the driver down to 100hz).
2' from driver's edge to back of the any baffle, that's my minimum distance.
That's a +3 to +6db Feq hump around 140hz, really pleasurable compared to a sealed speaker without baffle step.
Then I can also cross at 100hz (about as high as my ears like).
I don't care what simulations say.
It will short circuit the shortest distance to the back side.
In your case, a deeper box may make some resonances you don't want. But trying stuffing like you are, you may get a nice compromise.
You can make a rectangle and snug it up against the back of your box. That way you don't have to rebuild a box. I like the box idea, it really prevents having a large "sound board" launching who knows what. That's why I'm going the sand filled sandwich route.
Norman
Last edited:
I think standard rule of thumb for open backed boxes, is it should be no more than 1/4 deep as it is wide. Might be 1/3, I can't remember.
Then again, with foam around the backside (of the driver) of my ob screen, I heard no bad effects of having the wings straight back (parallel to each other). I can't figure it out.
Norman
Then again, with foam around the backside (of the driver) of my ob screen, I heard no bad effects of having the wings straight back (parallel to each other). I can't figure it out.
Norman
Last edited:
Member
Joined 2009
Paid Member
I think the usual guideline is not to have the two 'wings' of the baffle the same length so that the path length for sound between backside and frontside is different around the two sides and this reduces the peakiness in the bass response. Otherwise, your suggestion that a 2' box depth is about right appears consistent with my experience, although in my case the 2' sizing for OB was not intentional in this case - just happened to give the right volume for a sealed box and it matches the size of birch plywood that I can buy locally (and fit into my car). But even with my fully braced double skinned box it struggles to be perfectly 'dead' - a surf-board baffle would appear to stand no chance whatsoever in being sufficiently motionless. I have seen others struggle with this; some gave up and dangle their drivers on rope without a baffle, others have persevered and perhaps the sand filled approach is the best compromise.
Having the OB wings parallel is supposed to be bad - risk of 'box modes' or something. I can't test that out as my box is rigid and can't be changed but it's encouraging that you didn't observe an issue here. I suspect it's the room placement that makes the dominant impact here, I have my box pulled out from a corner so that the surfaces behind the box are not symmetrical to the box and I think this helps the overall sound. However, a big peak at 140Hz from the OB effect might be something I will try to moderate at line-level - another experiment to try.
I can't simply wedge a rectangle of foam in the back of my box due to the braces that stiffen the structure but it isn't a big stretch to figure out something that I can try. For example, I put some of my kids old clothes back inside the box - a bit like putting a block of foam on the back - and this reduces the amount of treble escaping out the back. I find this works well.
Subjectively, it appears that it's better to have the treble come from the front of the driver and not bouncing all over the walls behind as this creates a bit of smear and confusion in the sound. But having it open for the mids and the bass works wonders. This is just a thought - I may back-track on that later if further experiments show otherwise.
Having the OB wings parallel is supposed to be bad - risk of 'box modes' or something. I can't test that out as my box is rigid and can't be changed but it's encouraging that you didn't observe an issue here. I suspect it's the room placement that makes the dominant impact here, I have my box pulled out from a corner so that the surfaces behind the box are not symmetrical to the box and I think this helps the overall sound. However, a big peak at 140Hz from the OB effect might be something I will try to moderate at line-level - another experiment to try.
I can't simply wedge a rectangle of foam in the back of my box due to the braces that stiffen the structure but it isn't a big stretch to figure out something that I can try. For example, I put some of my kids old clothes back inside the box - a bit like putting a block of foam on the back - and this reduces the amount of treble escaping out the back. I find this works well.
Subjectively, it appears that it's better to have the treble come from the front of the driver and not bouncing all over the walls behind as this creates a bit of smear and confusion in the sound. But having it open for the mids and the bass works wonders. This is just a thought - I may back-track on that later if further experiments show otherwise.
Last edited:
maybe I had luck because of the distance from the driver to the floor and the top open.
An open backed box would be way different than a hinged open baffle.
I think a peak at 140hz is fine (even desired), so long as you are rolling into a subwoofer also (at least for most of my music).
either way, great and informative posts !!!!!!!!!!
If AN hadn't raised the price back when this thread was rolling along and measurements were posted, I'd have ordered a pair !!!!! That's ok, 12" works fne for me.
Norman
An open backed box would be way different than a hinged open baffle.
I think a peak at 140hz is fine (even desired), so long as you are rolling into a subwoofer also (at least for most of my music).
either way, great and informative posts !!!!!!!!!!
If AN hadn't raised the price back when this thread was rolling along and measurements were posted, I'd have ordered a pair !!!!! That's ok, 12" works fne for me.
Norman
Member
Joined 2009
Paid Member
You know, I don't think the pricing is off base. These are BIG drivers, you get a very nicely made cast frame along with a big cone and a good phase plug. I looked around and I don't see much that can compete with it. Actually I didn't find anything that can compete with it. You may have to buy two drivers and a cross over to equal what it can do and that may cost you more. Of course, very nice results, even better perhaps, can be obtained with other drivers but that's another question. The main problem is that it's a real commitment to put a cabinet this size into your house. At least us 'mono' guys only have the one to make, until of course we get the need to build something new 
lol
yup we get to try twice the stuff !!!!!!!!!!!
And you are right, it is brand new (an15) compared to $100 used for a single driver (my targets). No hunting on fleabay and hope you don't get a box of rocks. I forgot the an15 were cast frame. I know, know, a phase plug is better, but the dust cap in mine seems to work fine.
My usual setup (single speaker for music and movies) makes any full range sound garbled, necessitating a crossover. I'm still a bass head, from Sade and Rihanna, to Wreck It Ralph and Saving Private Ryan. Tron Legacy and Fight Club soundtrack are played often also.
What are the exact dimensions of your open backed box ?
Norman
yup we get to try twice the stuff !!!!!!!!!!!
And you are right, it is brand new (an15) compared to $100 used for a single driver (my targets). No hunting on fleabay and hope you don't get a box of rocks. I forgot the an15 were cast frame. I know, know, a phase plug is better, but the dust cap in mine seems to work fine.
My usual setup (single speaker for music and movies) makes any full range sound garbled, necessitating a crossover. I'm still a bass head, from Sade and Rihanna, to Wreck It Ralph and Saving Private Ryan. Tron Legacy and Fight Club soundtrack are played often also.
What are the exact dimensions of your open backed box ?
Norman
Member
Joined 2009
Paid Member
I suspect there are a few folk that don't like phase plugs or whizzer cones and a well designed dust cap is much preferred. I suspect the latest Mark Audio drivers do very well indeed with a dust cap. The bigger objection is usually the whizzer because it is really a mechanical cross-over and some may feel this is a compromise. But I remember what Bud Purvine had to say about this driver:
"Audio Nirvana Super 15 is the only one I have any experience with. The whizzer is THE BEST implementation of a whizzer I have encountered. It is a smooth horn attached to the voice coil, rather than the more abrupt whizzers in lesser AN models and everywhere else." "Easily the best large format full range driver ever and once EnABL'd easily one of the best drivers of any kind ever. Seriously, these things are better than the best flat panel drivers."
But there is that initial painful moment of looking at the price, when your credit card just won't wiggle free of your wallet and you think twice...
Good choice in movies - I tend to like to watch the movie more than listen to the soundtrack although I have got good mileage out of the soundtrack from Pulp Fiction. I don't use full range for movies - I tried with smaller full range drivers and now they're all gone, replaced with multiway units. The Big'un is for music though. Can't imagine having a 5 channel set up of Big'un speakers !
Dimensions? - The box is simple, it's made of 2' x 4' panels of Russian Birch. Now there are some adjustments to be made for panel thickness etc but I think the formula you use to calculate response are not accurate enough to care about these small differences.
"Audio Nirvana Super 15 is the only one I have any experience with. The whizzer is THE BEST implementation of a whizzer I have encountered. It is a smooth horn attached to the voice coil, rather than the more abrupt whizzers in lesser AN models and everywhere else." "Easily the best large format full range driver ever and once EnABL'd easily one of the best drivers of any kind ever. Seriously, these things are better than the best flat panel drivers."
But there is that initial painful moment of looking at the price, when your credit card just won't wiggle free of your wallet and you think twice...
Good choice in movies - I tend to like to watch the movie more than listen to the soundtrack although I have got good mileage out of the soundtrack from Pulp Fiction. I don't use full range for movies - I tried with smaller full range drivers and now they're all gone, replaced with multiway units. The Big'un is for music though. Can't imagine having a 5 channel set up of Big'un speakers !
Dimensions? - The box is simple, it's made of 2' x 4' panels of Russian Birch. Now there are some adjustments to be made for panel thickness etc but I think the formula you use to calculate response are not accurate enough to care about these small differences.
I love the sound of open voice coils and phase plugs over conventional dust cap.
I'm curious to try out those new drivers without the whizzer cone though.
jbl le8t ?
Google Translate
http://www.jblpro.com/pub/obsolete/le8t.pdf
Wasn't there a fostex 8" with a metal dustcap ?
It will be tough to get a 12" to do it (like the phy).
That isn't even a dustcap, granted it's falling just b4 10khz .............
But a 1 to 1.5" voice coil, copper cap, maybe shorting ring, and a strong magnet but not too strong (yucky climbing responses).
Google Translate
http://www.jblpro.com/pub/obsolete/le8t.pdf
Wasn't there a fostex 8" with a metal dustcap ?
It will be tough to get a 12" to do it (like the phy).
That isn't even a dustcap, granted it's falling just b4 10khz .............
But a 1 to 1.5" voice coil, copper cap, maybe shorting ring, and a strong magnet but not too strong (yucky climbing responses).
Last edited:
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.