An externally hosted image should be here but it was not working when we last tested it.
THAT is a dipole waveguide.
I hope that JohninCR doesn't mind my posting this pic. He incorporated OB theory along with Geddes waveguide theory in building these.
Let it be clear that I've been super pleased with OB so far and feel that this sort of design will only improve the experience.
The only problem I have is that of a young family and a demanding job. You guys feel what I'm saying? This is part of the reason why I just can't do all the measuring/design thing. I have a block of time and I make sawdust fly and screw a driver in. That's pretty much all I have time for. A pic or two of my baffles coming. I'm a bit bashful about them though.
Erik
Ok, here are some older pics of the baffles. They don't look just like this now but it gives you a general idea. See what I mean about ugly?
I was using the tripath amp just to test a few changes I had made. Those little amps are pretty cool but after a while they drive me nuts. I can't handle the digital nature of the sound and tubes bring me back to equilibrium.
Too many projects....
Erik
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
I was using the tripath amp just to test a few changes I had made. Those little amps are pretty cool but after a while they drive me nuts. I can't handle the digital nature of the sound and tubes bring me back to equilibrium.
Too many projects....
Erik
Hi Erik,
You're right, I spend too much time reading, and not enough time building. On the world of high-end audio, you're right there as well. I think technology completely favours the manufacturer and retailer, while dragging the poor old consumer along while he/she's continually shouting out that the new version isn't as good as the old. Some of these include in my opinion 2/4 track recordings vs 64/126+ multi-track recordings, vinyl records/tape vs cd's, valves/tubes vs transistors, paper cones vs exotic materials (although I do like Markaudio drivers). Then there's the fact that most recording engineers are now mixing music to sound good as MP3's being played on iPods through cheap earplugs. Now that scares the s#%t out of me!
Music is made up of vibrations. These vibrations get their tone from the composition and construction of the instrument that creates them - I think. Therefore, I agree with you that baffle vibrations probably aren't bad, it's just a matter of finding the synergy between the speaker driver and the baffle/soundboard that works the best for each different combination.
Is the dipole waveguide more like the U and H frame type arrangement? Unfortunately, the pic of your 15" drivers doesn't show up. The PE-16M's look very interesting. They also look like they'd weigh more than the 1kg that the data sheet shows!? Yes, the Tone Tubby Alnico San Rafael's appear to demand a closer look as you say. Damn that shipping weight/cost.
Thanks for providing further food for thought on the subject. I'm off to the shed now to find those old Bastanis baffle copies and do a little modifying.
Speak soon, I hope.
regards,
Simon
Erik, I've just seen the JohninCR Waveguides you posted, they look amazing - oh no more to read about 😀
You're right, I spend too much time reading, and not enough time building. On the world of high-end audio, you're right there as well. I think technology completely favours the manufacturer and retailer, while dragging the poor old consumer along while he/she's continually shouting out that the new version isn't as good as the old. Some of these include in my opinion 2/4 track recordings vs 64/126+ multi-track recordings, vinyl records/tape vs cd's, valves/tubes vs transistors, paper cones vs exotic materials (although I do like Markaudio drivers). Then there's the fact that most recording engineers are now mixing music to sound good as MP3's being played on iPods through cheap earplugs. Now that scares the s#%t out of me!
Music is made up of vibrations. These vibrations get their tone from the composition and construction of the instrument that creates them - I think. Therefore, I agree with you that baffle vibrations probably aren't bad, it's just a matter of finding the synergy between the speaker driver and the baffle/soundboard that works the best for each different combination.
Is the dipole waveguide more like the U and H frame type arrangement? Unfortunately, the pic of your 15" drivers doesn't show up. The PE-16M's look very interesting. They also look like they'd weigh more than the 1kg that the data sheet shows!? Yes, the Tone Tubby Alnico San Rafael's appear to demand a closer look as you say. Damn that shipping weight/cost.
Thanks for providing further food for thought on the subject. I'm off to the shed now to find those old Bastanis baffle copies and do a little modifying.
Speak soon, I hope.
regards,
Simon
Erik, I've just seen the JohninCR Waveguides you posted, they look amazing - oh no more to read about 😀
Erik, beauty is in the eye of the beholder, and I see nothing offensive there.
Can I ask what the tubes are on the inside edges of the baffles?
I recognised that little amp immediately. Mine sits under the desk at work, I'm a video editor, and I swear it is more revealing that the multi-thousand dollar systems that the audio I'm dealing with was originally mixed on. I agree, tubes just sound fuller/smoother yet surprisingly lack little of the detail of the t-amps - although for the money t-amps are...
Can I ask what the tubes are on the inside edges of the baffles?
I recognised that little amp immediately. Mine sits under the desk at work, I'm a video editor, and I swear it is more revealing that the multi-thousand dollar systems that the audio I'm dealing with was originally mixed on. I agree, tubes just sound fuller/smoother yet surprisingly lack little of the detail of the t-amps - although for the money t-amps are...
I can see, I can see! and yes, big is beautiful!!!
I've got to look for more Pioneer drivers!
Simon
I've got to look for more Pioneer drivers!
Simon
It appears that the dipole waveguide is lined with soft absorbent material? So it's not designed to work like a horn? Horns are usually built reflective, aren't they? Using the Visaton B200 I guess means that it is fullrange? Hmmm, time to Google JohninCR and Geddes. I gather not the creater of those photos of kids in pumpkins, although a kid in that waveguide could work.
Not that Geddes! Read some of his stuff and it will become clearer. Geddes himself uses a low density foam plug, something like 35 pores per inch. That is to attenuate what he calls HOM's, or High Order Modes. I forget the exact explanation but it is part of the nature of the wave guide that some of the upper frequencies end up with more energy. Others know better how to explain it. So, no it is not a horn as such, but you do get some significant gain. And the way that John built it with the 2" radius round overs to deal with edge diffraction and dipole really makes me want to try. I've been trying to figure out the best way to construct it.
Yes, the tubing. Well, it doesn't work so well at dealing with edge diffraction the way I did it. But it does effectively extend the baffle and therefore the front to back distance. I completely edged that small Hawthorne baffle with that tubing and it pretty dramatically improved the sound.
I think that the ideal baffle would be shaped something like John's but round, like a donut.
Hey Simon, since you seem pretty familiar with cone treatments do you know what might work for refreshing the doping on the surrounds of vintage drivers? Or even repairing? I accidentally punched a screwdriver through the surround of a Calrad Cr-12 12" FR driver and it nearly made me sick. Those Calrads are great drivers. Japanese, of course.
Cheers,
Erik
Yes, the tubing. Well, it doesn't work so well at dealing with edge diffraction the way I did it. But it does effectively extend the baffle and therefore the front to back distance. I completely edged that small Hawthorne baffle with that tubing and it pretty dramatically improved the sound.
I think that the ideal baffle would be shaped something like John's but round, like a donut.
Hey Simon, since you seem pretty familiar with cone treatments do you know what might work for refreshing the doping on the surrounds of vintage drivers? Or even repairing? I accidentally punched a screwdriver through the surround of a Calrad Cr-12 12" FR driver and it nearly made me sick. Those Calrads are great drivers. Japanese, of course.
Cheers,
Erik
Antripodean- The PAX-A25 look to be the bigger brother of the A20, the same six-cell horn and all> I would have thought that they would go low enough without the need for any additional driver. My A20s certainly satisfy my low frequency needs, but they are in big MF back loaded horns.
If its not rude - what sort of $$ are they in aussie?
Erik - the first link did not show up.
I am with you on the pimping of the driver - I toyed with the idea of replacing the caps, and the dammer varnish, but in the end I decided to leave well alone.
I drive my A20s from solid state - until recently a Rait 60-60, now an Acoustic Research A-04 that I recently picked up on TM. Both work well, the A-04 perhaps a little better, being lower powered, I can get the volume dial up a bit further.
Gotta go and deal with a light bulb - SWMBO!
If its not rude - what sort of $$ are they in aussie?
Erik - the first link did not show up.
I am with you on the pimping of the driver - I toyed with the idea of replacing the caps, and the dammer varnish, but in the end I decided to leave well alone.
I drive my A20s from solid state - until recently a Rait 60-60, now an Acoustic Research A-04 that I recently picked up on TM. Both work well, the A-04 perhaps a little better, being lower powered, I can get the volume dial up a bit further.
Gotta go and deal with a light bulb - SWMBO!
and - Oooooh - I like those big Pioneers! I have a thing for those older Japanese alnico drivers, I have a couple of pair of the coral Kabuki BX series, and love the big sound, but the best driver I have is a Richard Allan CG8t, which is fullrange simplicity at its best IMO.
Love the idea of the dipole setup, how to get them up to listening level tho'?
Great thread.
Love the idea of the dipole setup, how to get them up to listening level tho'?
Great thread.
Hey Papa Hemi,
How's about posting a couple of pics of the drivers you mentioned? I have a single Coral 12" woofer that is just insanely built. I wish it had a mate. For that matter, I wish I had the pair of 15" woofers that are on e*ay for $1000, but that is just insane pricing. I don't know anything about the Richard Allan CG8t, can you fill me in?
How's about posting a couple of pics of the drivers you mentioned? I have a single Coral 12" woofer that is just insanely built. I wish it had a mate. For that matter, I wish I had the pair of 15" woofers that are on e*ay for $1000, but that is just insane pricing. I don't know anything about the Richard Allan CG8t, can you fill me in?
Papa,
As far as getting the waveguides up to listening level, well, you could suspend them from the ceiling if you wanted!
Erik
As far as getting the waveguides up to listening level, well, you could suspend them from the ceiling if you wanted!
Erik
G'day guys,
Eric, most things I've read on speaker treatments have always stated not to treat the surround so I can't really help you there. I did have a look on the web though and found this site, if you're not already aware of it. They seem to sell surround glues and treatments. Oh, and some interesting drivers.
Adhesives and Surround Doping & Dampener | The Speaker Exchange®
Saw these PAX-30J on Ebay. They're not on your brochure Erik, they look older. Sadly, I can't justify the US$210 postage to Australia, but to those in the US they could be a bargain. He said he'd send the drivers and L-Pad without boxes if required. Might be of interest.
Pioneer PAX-30J SPEAKERS NICE SHAPE (eBay item 160499482467 end time 08-Nov-10 10:51:59 AEDST) : Electronics
Now, let me show you ugly. (see below)
Notes to self: Don't buy cameras from supermarkets. Remember to make proper baffle for PAX-25B. Make baffle driver cutout 10" to fit driver diameter.
Enough of the poor jokes. I couldn't wait any longer, it's Friday night and I've just spent 5hrs and the better part of a bottle of red wine listening to the PAX's mounted in my Bastanis ripoff baffles - because that's all I had handy. Despite the MDF, 8" driver cutout, and excess holes the thing didn't sound too bad. There was even some bass there, and I've never heard AC/DC (Bon Scott era) sound better - and I have to say it's never been a favourite of mine to listen to at home. The opening to 'Livewire' (guitar and bass) was just awesome (to steal a phrase from the kids)
Now to let the wine do some talking. (Feel free to ignore the following.)
I've come to a conclusion that may be correct, or could be completely wrong. I believe that the OB speaker suffers more from 'poor' recordings than any other. During my 5hrs listening I heard moments of brilliance, and I heard moments of garbage. I would have put this down to my 'poor' baffles, but, it seemed as always that some recordings sounded better than others, just that this time some sounded much better than normal and some much worse.
This is where my theory comes in. I haven't read about this before, but that doesn't mean that anyone hasn't put up the same theory. I think the reason that I heard some really bad music being reproduced wasn't completely the fault of my OB speakers, but that a lot of recordings contain phase errors. I think 'box' speakers make these errors a little easier to listen too due to the fact that we are only listening to, supposedly, one phase of the music. When we listen to OB we are listening to + and - phase as well as the other phase errors that already exist within the recording in + and - as well.
As audiophiles we have all read how phase errors shouldn't be introduced by our amplifiers, speakers, or their cones and crossovers, but I don't think I've heard anyone talk about the phase errors that already exist in our precious recordings. I shared a studio with a sound engineer for 5years. He was 'classically' trained by the Australian Broadcasting Commission (ABC) and taught me much about technical issues that most A/V editors wouldn't know or learn about these days. He always had a phase meter on his desk sitting between his speaker monitors. He is also the only audio engineer who I've sat with, who's had such a meter visible?! I used to enjoy watching its display go from vertical to horizontal to diagonal to just blobby.
I'm sorry I'm rambling but I've got no one else to talk to about this at 1:00am in the morning. Besides, we're all friends here, aren't we?
Think of all those older/live recordings that just sound right. Is the reason they sound more natural because they have less phase errors and less tracks with over production that only increases these errors? Surely it's easier to keep phase errors under control with simple production, that's assuming you are even checking for phase errors in the recording process.
Is this the reason so many dismiss the OB speaker without giving it a chance, when those who do more often than not fall in-love with it? Is it that they unfortunately started listening to OB with a 'bad' recording? It's also interesting to me that some of the people who deal with OB speakers commercially get involved recording there own music or test tracks. I mainly refer to JELabs and Siegfried Linkwitz, there may be more. Is this because they know good recordings sound great on OB and that lesser recordings can sound awful?.
If you made it this far, thanks for letting me ramble, and if you did I'm interested in any thoughts you may have on the above.
Simon
Eric, most things I've read on speaker treatments have always stated not to treat the surround so I can't really help you there. I did have a look on the web though and found this site, if you're not already aware of it. They seem to sell surround glues and treatments. Oh, and some interesting drivers.
Adhesives and Surround Doping & Dampener | The Speaker Exchange®
Saw these PAX-30J on Ebay. They're not on your brochure Erik, they look older. Sadly, I can't justify the US$210 postage to Australia, but to those in the US they could be a bargain. He said he'd send the drivers and L-Pad without boxes if required. Might be of interest.
Pioneer PAX-30J SPEAKERS NICE SHAPE (eBay item 160499482467 end time 08-Nov-10 10:51:59 AEDST) : Electronics
Now, let me show you ugly. (see below)
Notes to self: Don't buy cameras from supermarkets. Remember to make proper baffle for PAX-25B. Make baffle driver cutout 10" to fit driver diameter.
Enough of the poor jokes. I couldn't wait any longer, it's Friday night and I've just spent 5hrs and the better part of a bottle of red wine listening to the PAX's mounted in my Bastanis ripoff baffles - because that's all I had handy. Despite the MDF, 8" driver cutout, and excess holes the thing didn't sound too bad. There was even some bass there, and I've never heard AC/DC (Bon Scott era) sound better - and I have to say it's never been a favourite of mine to listen to at home. The opening to 'Livewire' (guitar and bass) was just awesome (to steal a phrase from the kids)
Now to let the wine do some talking. (Feel free to ignore the following.)
I've come to a conclusion that may be correct, or could be completely wrong. I believe that the OB speaker suffers more from 'poor' recordings than any other. During my 5hrs listening I heard moments of brilliance, and I heard moments of garbage. I would have put this down to my 'poor' baffles, but, it seemed as always that some recordings sounded better than others, just that this time some sounded much better than normal and some much worse.
This is where my theory comes in. I haven't read about this before, but that doesn't mean that anyone hasn't put up the same theory. I think the reason that I heard some really bad music being reproduced wasn't completely the fault of my OB speakers, but that a lot of recordings contain phase errors. I think 'box' speakers make these errors a little easier to listen too due to the fact that we are only listening to, supposedly, one phase of the music. When we listen to OB we are listening to + and - phase as well as the other phase errors that already exist within the recording in + and - as well.
As audiophiles we have all read how phase errors shouldn't be introduced by our amplifiers, speakers, or their cones and crossovers, but I don't think I've heard anyone talk about the phase errors that already exist in our precious recordings. I shared a studio with a sound engineer for 5years. He was 'classically' trained by the Australian Broadcasting Commission (ABC) and taught me much about technical issues that most A/V editors wouldn't know or learn about these days. He always had a phase meter on his desk sitting between his speaker monitors. He is also the only audio engineer who I've sat with, who's had such a meter visible?! I used to enjoy watching its display go from vertical to horizontal to diagonal to just blobby.
I'm sorry I'm rambling but I've got no one else to talk to about this at 1:00am in the morning. Besides, we're all friends here, aren't we?
Think of all those older/live recordings that just sound right. Is the reason they sound more natural because they have less phase errors and less tracks with over production that only increases these errors? Surely it's easier to keep phase errors under control with simple production, that's assuming you are even checking for phase errors in the recording process.
Is this the reason so many dismiss the OB speaker without giving it a chance, when those who do more often than not fall in-love with it? Is it that they unfortunately started listening to OB with a 'bad' recording? It's also interesting to me that some of the people who deal with OB speakers commercially get involved recording there own music or test tracks. I mainly refer to JELabs and Siegfried Linkwitz, there may be more. Is this because they know good recordings sound great on OB and that lesser recordings can sound awful?.
If you made it this far, thanks for letting me ramble, and if you did I'm interested in any thoughts you may have on the above.
Simon
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Hey Simon,
Thanks for the link. I'll check that out. The supposed PAX30J looks to me like a reworked 30A or B.
Frankly, I don't know much about about phase angles with regards to music. I'm a high voltage electrician and phase angles to me relate to protective relaying and fault currents. I don't know enough to discern when things are "out of phase". Can you educate me? I was a classical musician but simply try to discern the tone of instruments.
However, (speaking from a void of ignorance here) I think one reason that some recordings sound crap is because they simply are. OB is very revealing. Read some more Linkwitz. Do you know Fequal and Fpeak? I find that the OB sound is less placement dependent in a room, not independent but less dependant. Again, the room becomes the box. There are peaks and nulls that are difficult to design out of OB. JoshK sells a spreadsheet that is helpful(for modern drivers) in designing OB shapes. It's called ABCbaffle or something like that. I bought it and used it for a while.
Dunno what you are talking about. UGLY? looks fine to me. But you won't be getting any satisfying bass from that(as I'm sure you know).
I gotta go, but yes, I feel the fraternity of the OB brotherhood is thick here. You are strong in the Force.
Cheers,
Erik
Thanks for the link. I'll check that out. The supposed PAX30J looks to me like a reworked 30A or B.
Frankly, I don't know much about about phase angles with regards to music. I'm a high voltage electrician and phase angles to me relate to protective relaying and fault currents. I don't know enough to discern when things are "out of phase". Can you educate me? I was a classical musician but simply try to discern the tone of instruments.
However, (speaking from a void of ignorance here) I think one reason that some recordings sound crap is because they simply are. OB is very revealing. Read some more Linkwitz. Do you know Fequal and Fpeak? I find that the OB sound is less placement dependent in a room, not independent but less dependant. Again, the room becomes the box. There are peaks and nulls that are difficult to design out of OB. JoshK sells a spreadsheet that is helpful(for modern drivers) in designing OB shapes. It's called ABCbaffle or something like that. I bought it and used it for a while.
Dunno what you are talking about. UGLY? looks fine to me. But you won't be getting any satisfying bass from that(as I'm sure you know).
I gotta go, but yes, I feel the fraternity of the OB brotherhood is thick here. You are strong in the Force.
Cheers,
Erik
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Oh, and let me tell you, these would be worth what this guy is asking. They've been relisted at least once. I have a pair that are older. The tweeter horns, as I've said repeatedly, are absolute gold. By far better than any coaxial with cone tweeters that I've had. The only thing they need is an LPad. These are PRO drivers that look like industrial tooling, as DMason says.
Erik
Erik
Simon, another thought. Older recordings were, I think, true stereo. Most modern recordings are not. Could that contribute to what you are experiencing as well?
I find that the bitrate of my files makes a huge difference. Shoot, even the USB cable to the DAC makes a difference to the sound. So very many things seem to affect the sound, but the main ingredients, once sorted out seem to get you most of the way there, whether you are using solid 18AWG silver wire to your speakers or not.
I find that the bitrate of my files makes a huge difference. Shoot, even the USB cable to the DAC makes a difference to the sound. So very many things seem to affect the sound, but the main ingredients, once sorted out seem to get you most of the way there, whether you are using solid 18AWG silver wire to your speakers or not.
Ok, I uploaded some old pics just for fun:
This is that Coral woofer I was talking about. AMAZING build quality.
Check this out. Quad Alnico slugs!
This was the first JELabs baffle. MDF. Yuck.
This is where it all started with vintage drivers. One of my other hobbies in the background(coffee).
Some mounting details of the Calrad CX12's. These were rated 103dB. I just couldn't stand the bass after a while. Qts was too high I believe and the bass was just too flabby, regardless of the amplifier.
Baffles are getting smaller! These put the drivers a bit too low. But the boundary gain from the floor really helped that "low" end.
I've hit my limit on uploading files into the forum here. I guess I'll have to put more in my picasa album.
Cheers,
Erik
This is that Coral woofer I was talking about. AMAZING build quality.
Check this out. Quad Alnico slugs!
This was the first JELabs baffle. MDF. Yuck.
This is where it all started with vintage drivers. One of my other hobbies in the background(coffee).
Some mounting details of the Calrad CX12's. These were rated 103dB. I just couldn't stand the bass after a while. Qts was too high I believe and the bass was just too flabby, regardless of the amplifier.
Baffles are getting smaller! These put the drivers a bit too low. But the boundary gain from the floor really helped that "low" end.
I've hit my limit on uploading files into the forum here. I guess I'll have to put more in my picasa album.
Cheers,
Erik
Wow! I was going to start another thread on the CG8Ts, but seeing Viridian load all that fancy stuff here - I thought why not do it too. I have to say the Coral 12" woofer in the BX series is nothing like that giant you have - engineered to the max! The alnicos in the BX are more like this:
Stamped frame, otherwise all OK - accordian suspension, paper cone, alnico magnet.
I mostly enjoy a fullrange speaker, but they do have their limitations, particularly when I want to rock out, that is when the Corals come into their own, a loud wall of sound, tho' it is hard to get them into the house, they do not suit SWMBO, particularly on their stands 😱:
The wee speakers on top are akai SW30, they are a 4" fullranger - a Radio Shack 40-1197 clone (I think) in a labyrinth cabinet.
As for my favourite, the Richard Allan CG8T. I have them in a folded TQWL cabinet the same as the Pioneer A20, only somewhat smaller:
here is their construction thread:
TQWP Richard Allan - AudioEnz Forums
and some other threads on them:
Richard Allan CG8T
Richard Allan Drivers - AudioKarma.org Home Audio Stereo Discussion Forums
They were a quite common driver in their day, but seem to be quite rare now. I would recommend them to anyone.
Open baffles - I have used these when trialling drivers and really do like the openness and natural sounding quality, it will be an avenue for exploration, buy once again I can see that SWMBO will not be impressed.
Gapmedia, I feel that you have hit the nail on the head in the quality of recorded music and phase alignment. This is the reason that I prefer a single fullrange speaker, there is no crossover and no need for any phase correction in the output (however this will not address any error in source material). KISS.
Stamped frame, otherwise all OK - accordian suspension, paper cone, alnico magnet.
I mostly enjoy a fullrange speaker, but they do have their limitations, particularly when I want to rock out, that is when the Corals come into their own, a loud wall of sound, tho' it is hard to get them into the house, they do not suit SWMBO, particularly on their stands 😱:
The wee speakers on top are akai SW30, they are a 4" fullranger - a Radio Shack 40-1197 clone (I think) in a labyrinth cabinet.
As for my favourite, the Richard Allan CG8T. I have them in a folded TQWL cabinet the same as the Pioneer A20, only somewhat smaller:
here is their construction thread:
TQWP Richard Allan - AudioEnz Forums
and some other threads on them:
Richard Allan CG8T
Richard Allan Drivers - AudioKarma.org Home Audio Stereo Discussion Forums
They were a quite common driver in their day, but seem to be quite rare now. I would recommend them to anyone.
Open baffles - I have used these when trialling drivers and really do like the openness and natural sounding quality, it will be an avenue for exploration, buy once again I can see that SWMBO will not be impressed.
Gapmedia, I feel that you have hit the nail on the head in the quality of recorded music and phase alignment. This is the reason that I prefer a single fullrange speaker, there is no crossover and no need for any phase correction in the output (however this will not address any error in source material). KISS.
Viridian - You may be interested in this site, lots of old Coral catalogues:
* Michael Otto's Archiv * - Home > CORAL
* Michael Otto's Archiv * - Home > CORAL
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