Thank you for your effort! And for the advice to not screw with mother nature. I do recall now, the need to center the tweeter above the woofer.
You know... I'll figure on using the 2.7 cu ft box. And I will go ahead and pick up some MDF and get the 4 drivers ordered tomorrow. This ought to be entertaining.
Thanks!
You know... I'll figure on using the 2.7 cu ft box. And I will go ahead and pick up some MDF and get the 4 drivers ordered tomorrow. This ought to be entertaining.
Thanks!
Hi Norman - What did you decide on for a tweeter? If I was doing this with off the shelf stuff I would be looking at the B&G Neo 3 - BUT it has limited dispersion in the vertical plane so it really needs to be placed near listening height.
Attached is the response for the Pioneer plotted in WinISD beta. I loaded the values shown from Parts Express and not the ones that came with WinISD for the graphs. The green plot shows the Pio with a 4 inch dia. by 9 inch long port and the yellow plot is for a sealed enclosure - you should be somewhere in-between the two.
BTW - do use a subwoofer in a separate enclosure to fill out the bottom end and for HT
Attached is the response for the Pioneer plotted in WinISD beta. I loaded the values shown from Parts Express and not the ones that came with WinISD for the graphs. The green plot shows the Pio with a 4 inch dia. by 9 inch long port and the yellow plot is for a sealed enclosure - you should be somewhere in-between the two.
BTW - do use a subwoofer in a separate enclosure to fill out the bottom end and for HT
Attachments
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thanks Thomas for the graphs. I did get WinISD and I want to duplicate what you have done to help with further changes.
I looked at a previous post of yours that showed a piece of felt over a vent hole in the back of the Pioneer. So evidently, there is a hole through the magnet...?
Also, you mentioned not to use a subwoofer. I don't have one, but, I guess you say that because this speaker could end up going down to about 30 Hz at the 3 db point? If so, I imagine in order to use a subwoofer, you would have to roll the bass over a little higher on the Walsh?
I should probably just use the tweeter you guys mentioned in this thread. When I went looking for that one. I found others. (oh no) I was looking at a Morel DMS 30. The only reason would be to allow handling of higher power. Is there a reason for that? It is a lot more expensive. I really just want it to have a wide horizontal dispersion and to be flat like the original Walsh's. Don't know what else to look for without hearing it. Probably should have the magnetic shielding the original tweeter has.
I looked for your B&G, but didn't find it. Does Parts Express have it?
Thanks for the help Thomas. I am trying to fight off other priorities to progress this. It's very interesting and timely for me.
I looked at a previous post of yours that showed a piece of felt over a vent hole in the back of the Pioneer. So evidently, there is a hole through the magnet...?
Also, you mentioned not to use a subwoofer. I don't have one, but, I guess you say that because this speaker could end up going down to about 30 Hz at the 3 db point? If so, I imagine in order to use a subwoofer, you would have to roll the bass over a little higher on the Walsh?
I should probably just use the tweeter you guys mentioned in this thread. When I went looking for that one. I found others. (oh no) I was looking at a Morel DMS 30. The only reason would be to allow handling of higher power. Is there a reason for that? It is a lot more expensive. I really just want it to have a wide horizontal dispersion and to be flat like the original Walsh's. Don't know what else to look for without hearing it. Probably should have the magnetic shielding the original tweeter has.
I looked for your B&G, but didn't find it. Does Parts Express have it?
Thanks for the help Thomas. I am trying to fight off other priorities to progress this. It's very interesting and timely for me.
There is a vent hole through the Pioneer magnet - combined with cutting the hole in the dust cap that is how the speaker is getting vented. I covered the rear hole because stuff tends to fall into it and took off one of the 3 felt pads mounted to the dust cap to compensate.
I did not mention to NOT use a sub-woofer. I DO use a sub-woofer!!
Choice of tweeters is up to you - I do believe that Mamboni wound up using a second rear firing tweeter to fill out the "omni sound" but I forget if he actually did it or was thinking about it. I used a dipole tweeter in order to keep things as "omni" as I could and I'm happy with the very large listening area. The trade off is sensitivity but these things still go loud enough for my needs.
B&G at
Parts Express = Parts-Express.com:*Bohlender Graebener Neo3-PDRW Planar Tweeter w/Back Cup | neo3pdr planar tweeter ribbon tweeter planar transducer not a bad little tweet for $44 each
I did not mention to NOT use a sub-woofer. I DO use a sub-woofer!!
Choice of tweeters is up to you - I do believe that Mamboni wound up using a second rear firing tweeter to fill out the "omni sound" but I forget if he actually did it or was thinking about it. I used a dipole tweeter in order to keep things as "omni" as I could and I'm happy with the very large listening area. The trade off is sensitivity but these things still go loud enough for my needs.
B&G at
Parts Express = Parts-Express.com:*Bohlender Graebener Neo3-PDRW Planar Tweeter w/Back Cup | neo3pdr planar tweeter ribbon tweeter planar transducer not a bad little tweet for $44 each
Ahhh... Use a sub-woofer. I've cleaned my glasses. Good idea you had about moving one piece of felt to the rear. Makes sense.
I didn't realize what B&G stood for. With your giving me the part number for it, I'll see if I can find those. thanks for looking that up. They are currently out of stock at PE. What about the spec that states they are good for 20 watts RMS. Would that indicate that they could be burnt up? It says 50 watts peak. Are you careful with yours?
It would seem that the dipole arrangement would be a good idea since the Walshes are supposed to be omnis. Have you played with blocking the rear to determine the difference?
I didn't realize what B&G stood for. With your giving me the part number for it, I'll see if I can find those. thanks for looking that up. They are currently out of stock at PE. What about the spec that states they are good for 20 watts RMS. Would that indicate that they could be burnt up? It says 50 watts peak. Are you careful with yours?
It would seem that the dipole arrangement would be a good idea since the Walshes are supposed to be omnis. Have you played with blocking the rear to determine the difference?
In the reviews some folks complain about blowing up the Ne03's - but Mamboni puts a 4 ohm 10 watt resistor in series to trim his tweets back a bit to match the 10 inch Pioneers.
I'm using ESS AMT1's Parts-Express.com: ESS Great Heil Air-Motion Transformer | ESS Great Heil Air-Motion Transformer amt amt-1 ribbon dipole tweeter walsh tweeter ess labs npa00511 with my units and would up putting in 16 ohm 10 watt resistors in series to get them to match the Pioneers.
The B&G Neo 8 Parts-Express.com: Bohlender Graebener Neo8-PDR Planar Transducer | neo8pdr planar tweeter ribbon tweeter planar transducer should be a better match - but it cost more $$$$ (ooooof course!)
I have not blocked off the rear of my AMT's - I like the dipole mode - and seeing as how the Pioneers are doing most of the work up to 7kHz it would not make much sense (to my thinking) to do that. YMMV and it's what YOU are after that counts anyway!
Wow... your AMT's are worth more than my car. But they must sound very nice. I have no way to know how to compare their sound with the sound of the original tweeter. All I can figure is that the AMT has to be the best tweeter available and therefore must sound better than the rest or no one would buy them. I guess you haven't really experimented with different ones to compare the sound.
And the series resistor sounds as though it would be a must.
My goal here is to attempt to come as close as I can in duplicating the imaging and sound quality I remember hearing from my friend's Ohm F's back in '74.
Thank you Thomas for your continued support.
Norm
But they must sound very nice. I have no way to know how to compare their sound with the sound of the original tweeter. All I can figure is that the AMT has to be the best tweeter available and therefore must sound better than the rest or no one would buy them. I guess you haven't really experimented with different ones to compare the sound.And the series resistor sounds as though it would be a must.
My goal here is to attempt to come as close as I can in duplicating the imaging and sound quality I remember hearing from my friend's Ohm F's back in '74.
Thank you Thomas for your continued support.
Norm
The ESS AMT's are pretty hard to beat - but everyone has their different needs and taste and some folks prefer other tweeters.
Take a look here for some good input on tested tweets Zaph|Audio - perhaps one that is a better budget fit for you. However - if you need 4 of them (2 front firing and 2 rear firing) then the B&G Neo 8's might be your best value.
The one thing I do know for sure - once I listened to AMT's I couldn't go back to conventional domes - just not the same. That being said - not all AMT's are created equal - just like all domes are not created equal.
Take a look here for some good input on tested tweets Zaph|Audio - perhaps one that is a better budget fit for you. However - if you need 4 of them (2 front firing and 2 rear firing) then the B&G Neo 8's might be your best value.
The one thing I do know for sure - once I listened to AMT's I couldn't go back to conventional domes - just not the same. That being said - not all AMT's are created equal - just like all domes are not created equal.
I don't suppose you could try to put into words what it was about the AMTs that stole you away from domes.
It would probably be like me trying to explain why I thought the Ohm F's were perfect. Another concern I have now is that I have grown different internal ear components than I had before. (49 - for the 12th time)
It would probably be like me trying to explain why I thought the Ohm F's were perfect. Another concern I have now is that I have grown different internal ear components than I had before. (49 - for the 12th time)
I can still hear 17kHz but there are other things that I listen for besides Frequency. I suppose that I would call it "coloration" - in that given two speaker drivers of the same size and frequency range some will (subjectively) seem to be "cold" - "neutral" - "warm" etc. Additionally some drivers will seem to have a bit of an edge to them while others seem a bit slow and bloated. You can spot some of this with the waterfall diagrams but that only tells the story for the raw speaker and not for how it sounds in it's end application (box - open baffle - line array etc.) and associated components such as crossovers and baffles. The ESS AMT1's work one way - mount them at ear height and let 'em rip.
Properly driven and crossed over they have very low distortion and don't color the reproduced sound and thus have a "clean and open" presentation that once heard is hard to give back.
The real acid test is how long can I listen to a speaker without getting listener fatigue or just plain getting tired of listening. If I'm still dialing up tunes three or four hours after I start and SWMBO is telling me that it's late and time to go to bed - that's when I start believing I have a pretty good speaker going. If I can't enjoy listening to it for three or four hours - something ain't right.
Interesting. I can probably hear 17 kHz as well as long as it is being driven by 17 kW. (not actually positive, but I'm afraid I can no longer hear that high).
How important do you think the amplifier is? I listened to some nice speakers the other day in a specialty shop. Their cost was $6500. The amp was a SimAudio 150 watt 2 channel system that cost thousands. The guy couldn't believe I was planning to use an Onkyo 100watt/channel 7.2 receiver to drive speakers for music. He explained that was ok for HT, but not music. I'm in a situation where I just don't know how guilty I should feel for not using a "good" 1 or 2 channel amp.
How important do you think the amplifier is? I listened to some nice speakers the other day in a specialty shop. Their cost was $6500. The amp was a SimAudio 150 watt 2 channel system that cost thousands. The guy couldn't believe I was planning to use an Onkyo 100watt/channel 7.2 receiver to drive speakers for music. He explained that was ok for HT, but not music. I'm in a situation where I just don't know how guilty I should feel for not using a "good" 1 or 2 channel amp.
IMO - a good amp is a good amp and Onkyo makes some nice stuff. My previous amp was a 5.1 Onkyo and for everyday use it was fine. I upgraded to a Harmon Kardon AVR354 which at the time was the only unit I could find that had pre-amp outputs. It has worked fine for me with no problems except that it runs hot as a pistol.
One of our highly renowned speaker designers here has used a Pioneer to demo his speakers with and makes no apologizes for it.
A "premo" amp is one component of a "premo" system and ALL of the components should be of like quality or else you are just *issing up a rope.
To get appreciably better sound usually will result in a very large penalty in terms of $$$$ spent. I have chased that shadow of "best (whatever)" before and have learned to accept "good enough is good enough". That's what got me back into DIY audio - being able to make some pretty darn good stuff for reasonable bucks. A set of speakers such as these should be a pretty good start to having a system that will reward you with many hours of enjoyment without spending the bulk of your 401K fund. Plus - for me - there is simply the pleasure of having a [fill in the blank] that sounds as good or better than something that cost 10 times more.
Keeps the hands and mind busy too. IF you want a really great amp there are plenty of designs available here - take a look at the Pass threads for really top end stuff that can be built for not that much and it will perform every bit as well as any amp over $5000.
The real question is - do you really want a system that plays at that level? Remember - the rest of the parts will need to match because at that level even minor things can make a difference. Chasing that shadow can be a long and winding road. The excursion can be a wonderful pleasure with great rewards. It can also be expensive, time consuming, and frustrating. It can be done - but plan ahead. In the meantime your Onkyo will be just fine.
Above all - enjoy the journey 'cause that's what DIY is all about.
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Wow. Nicely said.
I do have a specific question regarding amplifier power supplies. BTW, I've worked with electronics since I was 10, I would guess. My career was in telecommunications, but can you explain what bad things you actually would hear when a receiver with a switching power supply is used rather than a more expensive transformer based power supply? I imagine you could hear some very low level hash.... Actually maybe not. But, is there an issue with the switching supply not being able to maintain as constant of a DC output and that that would or does result in you hearing....... [some defect] in the music?
The guy at the stereo place explained that the SimAudio used torridial transformers and that, for music, you wouldn't want to use a receiver with a switching supply. Of course, I asked why, but his explanation left me unconvinced.
Thanks Thomas
I do have a specific question regarding amplifier power supplies. BTW, I've worked with electronics since I was 10, I would guess. My career was in telecommunications, but can you explain what bad things you actually would hear when a receiver with a switching power supply is used rather than a more expensive transformer based power supply? I imagine you could hear some very low level hash.... Actually maybe not. But, is there an issue with the switching supply not being able to maintain as constant of a DC output and that that would or does result in you hearing....... [some defect] in the music?
The guy at the stereo place explained that the SimAudio used torridial transformers and that, for music, you wouldn't want to use a receiver with a switching supply. Of course, I asked why, but his explanation left me unconvinced.
Thanks Thomas
I worked Space Base Telecom in my younger days and then move up to some really fun stuff - Meteorological Systems - transportable, fixed, and space based. Real science! Cooool stuff!
SMPS - Switch Mode Power Supplies - a veeeeery long and deep topic discussed on other threads here - as well a power supply design and regulation per se. Seeing as how this is a thread about knocking together some Walsh type speakers a discussion about those little toys should be taken over to one of those threads or attempted via PM's. I don't have a short answer on the topic other than Power supply rejection ratio - Wikipedia, the free encyclopedia and Switched-mode power supply - Wikipedia, the free encyclopedia.
I repaired a bunch of very precise electronics gear that used SMPS - as long as you can filter out the hash things should be good. Regulation for sure can be better than a simple transformer based PS - but you can make some pretty darn good supplies with transformers and regulation circuits. Of course any power supply needs to be properly rated for the job at hand (and sometimes bigger is not always better).
A properly designed and used SMPS will normally provide BETTER regulation than your run of the mill transformer based supply. When they start acting up tho they will drive you NUTS!!
They add a lot of complexity to what should be a simple design. If properly filtered and shielded (not easy) SMPS can be a good choice - but it's gonna cost ya.Toroid transformers are nice things - but they aren't a magic bullet that will solve all sins of a bad power supply design. They just take up less space and look neat. Well - ok - they really do work better for PS design than the regular xformers - heck I use 'em all the time with my stuff - but I wouldn't turn up my nose at something that didn't have one in it.
I received the following response to a PM I sent regarding the use of a square enclosure for the Walsh-work-alike.
Sure, a square cabinet will work fine. That specific 10" Pioneer woofer I
used had TS parameters suitable for acoustic suspension or aperiodic
(resistive vent) enclosure.
Good luck. Please post you work at DIYaudio.
Bob
Sure, a square cabinet will work fine. That specific 10" Pioneer woofer I
used had TS parameters suitable for acoustic suspension or aperiodic
(resistive vent) enclosure.
Good luck. Please post you work at DIYaudio.
Bob
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Cooooool! That's good news!!
BTW - the reason that most (but not all) audiophiles get a little picky about HT amps is that they object to some of the enhanced "music modes" as being to "colored" to be considered "unadulterated" reproduction. Also some of the digital conversion methods are compromised when compared to the real thing i.e. a good turntable and cart or a lossless music server or a audiophile rated CD/SCAD player (with modifications and cryo treated - silver plated solid core interconnects etc.).
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I received the following response from a PM I sent to BudP regarding the purpose and advantages of EnABL.
There are a couple of characteristics that EnABL tackles. As a cone is struck by the voice coil two different waves are emitted. One is the theoretically perfect compression wave that is emitted by the portion of the cone that remains in minimum phase with the voice coil. This is called the pistonic region and response. Another wave front is unleashed within the body of the cone and is called a transverse wave. This wave rigs within the cone until the surround finally turns it into heat. The transverse waves are what cause the cone to only have a central region of pistonic action, with the rest of the cone exhibiting "breakup".
EnABL disperses the transverse wave emergence and consequent feedback through the air to the voice coil. This is just a postulated mechanism as we have no way to actually view the events. Once applied, the EnABL pattern appears to force the energy provided at the resonance node to either not arise, or arise with such a narrow Q that it cannot propagate or become a coherent addition to the passing compression wave , or perhaps, all three of these. In any event, the transverse wave is travelling through the cone at approximataly 3 times the speed of the compression wave through air, so it has time to do all of those things that make speakers sound like speakers, rather than the music they are supposed to be portraying.
You can look here for a simulation of how energy arises in resonance from a an emitting surface. It is not a direct correlation but will give you a guide in thinking about this stuff.
(Note: The links must be copied and pasted to work)
http://www.youtube.com/watch?v=sY6z2hLgYuY
http://www.youtube.com/watch?v=kWadDtIFPNs
http://www.youtube.com/watch?v=_bAmjRK9wBA
http://www.youtube.com/watch?v=3csi-2Hrzhg
There has been a great deal of argument about the exact method with which EnABL goes about it's business and to date only a few actual tests that show anything is altered. Here is one from John K that shows what an EnABL pattern at the boundaries of a cone does for the sound involved. He did not apply a pattern to specifically disperse the major resonance node. Look carefully at the blink comparison of that resonant node and notice the depiction of ringing that shows up in the treated driver.
http://planet10-hifi.com/johnK-test/
This is the other thing EnABL provides, a significant coherence to signals some 50 to 60 dB down from the usual point where all drivers seem to loose coherent portrayal of the information, about 40 dB below maximum signal level. This means you can actually make sense out of signal some 90 dB down from maximum signal level, just as you can in real space with live players and instruments you can touch.
Here is a tutorial on EnABL treatment of speakers that you should read.
http://www.diyaudio.com/forums/showthread.php?postid=1460272#post1460272
Dr Mamboni's triangles will perform some of these activities by controlling those transverse waves that emit on both sides of the cone, which is a great help to clarity in a large format cone driver. He and I have speculated about what a fully EnABL'd and Mambonied cone driver would sound like, but neither of us has actually done the work yet.
Hope this helps some.
Bud
There are a couple of characteristics that EnABL tackles. As a cone is struck by the voice coil two different waves are emitted. One is the theoretically perfect compression wave that is emitted by the portion of the cone that remains in minimum phase with the voice coil. This is called the pistonic region and response. Another wave front is unleashed within the body of the cone and is called a transverse wave. This wave rigs within the cone until the surround finally turns it into heat. The transverse waves are what cause the cone to only have a central region of pistonic action, with the rest of the cone exhibiting "breakup".
EnABL disperses the transverse wave emergence and consequent feedback through the air to the voice coil. This is just a postulated mechanism as we have no way to actually view the events. Once applied, the EnABL pattern appears to force the energy provided at the resonance node to either not arise, or arise with such a narrow Q that it cannot propagate or become a coherent addition to the passing compression wave , or perhaps, all three of these. In any event, the transverse wave is travelling through the cone at approximataly 3 times the speed of the compression wave through air, so it has time to do all of those things that make speakers sound like speakers, rather than the music they are supposed to be portraying.
You can look here for a simulation of how energy arises in resonance from a an emitting surface. It is not a direct correlation but will give you a guide in thinking about this stuff.
(Note: The links must be copied and pasted to work)
http://www.youtube.com/watch?v=sY6z2hLgYuY
http://www.youtube.com/watch?v=kWadDtIFPNs
http://www.youtube.com/watch?v=_bAmjRK9wBA
http://www.youtube.com/watch?v=3csi-2Hrzhg
There has been a great deal of argument about the exact method with which EnABL goes about it's business and to date only a few actual tests that show anything is altered. Here is one from John K that shows what an EnABL pattern at the boundaries of a cone does for the sound involved. He did not apply a pattern to specifically disperse the major resonance node. Look carefully at the blink comparison of that resonant node and notice the depiction of ringing that shows up in the treated driver.
http://planet10-hifi.com/johnK-test/
This is the other thing EnABL provides, a significant coherence to signals some 50 to 60 dB down from the usual point where all drivers seem to loose coherent portrayal of the information, about 40 dB below maximum signal level. This means you can actually make sense out of signal some 90 dB down from maximum signal level, just as you can in real space with live players and instruments you can touch.
Here is a tutorial on EnABL treatment of speakers that you should read.
http://www.diyaudio.com/forums/showthread.php?postid=1460272#post1460272
Dr Mamboni's triangles will perform some of these activities by controlling those transverse waves that emit on both sides of the cone, which is a great help to clarity in a large format cone driver. He and I have speculated about what a fully EnABL'd and Mambonied cone driver would sound like, but neither of us has actually done the work yet.
Hope this helps some.
Bud
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Between my wife's recent heart surgery (mitral valve repair) and having our 16 YO granddaughter move in with us (Sept. 09) and the assorted teen-age boyfriends - gal buddies etc. my life is little else but constant distractions. I'd hate to think what it would be like if I was still work'n for a living!!
I'm interested in your progress!!! Please keep us posted - even if there are some hic-up's along the way it's nice to share the info for others that might travel this path someday in the future.
Well Thomas, most importantly, I hope your wife is doing fine. And it sounds like you do have your hands full with a young teenage girl living there. I had two of those, who are now both married.
Somehow the links in my EnABL posting above have extra info attached to them, rendering them non-functional. Not sure how to fix them.
Somehow the links in my EnABL posting above have extra info attached to them, rendering them non-functional. Not sure how to fix them.