| pekar |
Here's one I've been keeping under wraps, but it's time to share.
Use the Aura NS3-194-8E, on sale for $10.50 from Madisound.
http://www.madisound.com/cgi-bin/in...0.9881&pid=1705
Ignore the fs, it does far better than the numbers indicate.
Especially in my box.
One half sheet of MDF (you might could squeeze it out of a quarter sheet, with no mistakes)
Some padding for the back wall ( felt or carpet pad)
2"dia PVC (you can play with the port size)
1/2"hardwood face, or use 1/2" MDF or birch ply if you have to, but it won't sound as good. Mine is maple.
I developed this for use with the t-amp, and have found it works very well with the higher powered amp6.
I present this as an experimental starting point, and welcome suggestions.
design goals were-
cheap,
simple,
audiophile sound,
no crossover, just a driver (mechanical mods only),
rock the party.
plans at -
http://www.flickr.com/photos/47642593@N00/295706737/
Just build 'em- I think you'll be glad you did.
Pekar |
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| pekar |
| Bottom pic. These are prototypes, I have yet to make the pretty pair. |
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| Scottmoose |
| Reminds me of the Hawaii 5.0 for the defunct RS40-1354. Nice work. |
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| moray james |
| wondering if the pipe section can be replaced with a rectangular section of vent that runs up the inside of the back wall? You might even get away with just a slot in the bottom at the back edge. That way if you place a bottom on the cabinet you can stand mount the speaker and your vent still works. Is there a special interaction going on between the two vent sections in this design? As it stands the vent action will be modified depending on what kind of surface the speaker sits on (ie. smooth floor or carpeted). Comments? Regards Moray James. |
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| Spasticteapot |
Memo to self:
Buy some of these. |
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| GG |
Nice little inexpensive project.
What sort of finish are you planning for the enclosure? |
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| pekar |
I intended that these be set on a hard surface like a desktop or bookshelf, not the floor. It would be easy enough to incorporate a bottom for other uses.
You can do whatever you want with the vent, but
I already tried the slot idea, with inferior results. Vents along walls are generally a bad idea.
I plan to use some birdseye maple for the face, with a painted body.
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| 2020audio |
| Trying these same drivers in small sealed box, what volume and tuning freq are you using and are you happy with the sound? Ref my thread http://www.diyaudio.com/forums/show...threadid=90151. I still think a TL is the solution but haven’t gotten any feed back yet. And to james as long as you know then box tuning freq a rect port should be easy to calculate. |
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| moray james |
provide
a broader BW in terms of load as compared to round or square ducts.
Seemed simpler to construct with all rectangular vents and I can see no advantage to switching to a round tube duct (in keeping with the design goal of ease of build). You could stretch this into two ducts and have a mini Onken design. This would also provide some internal cabinet reinforcment. Regards Moray James. |
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| pekar |
The attached pic. is similar to what I tried, and was unhappy with the result.
Your idea is interesting, reminds me of the Solo-103.
This box is really quite small, and with 3/4" walls needs no bracing, IMO.
Pekar |
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| moray james |
| yes that is what I had thought as it keeps things very simple with now round holes to cut or pipe to buy. What ever the tunning of the pipe you are using it can be matched this way without much effort. Dave Dlugos (PLANET 10) has a design for a mini Onken for a Fostex Fe127e on his site. While the tunning is lower than would be for your design the size is close and retunning the vents could be done to suit your driver. Though given the rather high Fs I am not sure there is really a lot of point to it as a sealed bos of not a lot of volume should attain the similar results but it is a nice design. Regards Moray James. |
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| BAM |
| As built, that lower chamber forms an acoustic lowpass which probably helps stop any upper midrange leakage from the port. Pekar, have you tried listening to these on their side (defeating the slot-loading of the vent)? Do you notice a change in performance? Or, can one be measured? |
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| pekar |
I don't find round ports especially inconvenient. I've done it with a 2" holesaw by butting the pvc to the hole and gluing it in place.
I did use a router to cut the 2 3/8" hole for the enclosure in the picture.
It depends on which tools are at hand.
When tipped on its side bass performance suffers.
I would also like to point out that this driver was designed by Ben Tang, and that it has a neodymium magnet.
Pekar |
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| pekar |
| I've modeled Delsol in google sketchup. |
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| pekar |
Bottom view.
If there's any interest I can figure out a way to pass on Delsol's Sketchup file, if you want to give it a spin. I haven't seen many using this program yet, but it's free and pretty powerful.
Pekar |
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| planet10 |
Go to the Google menu & Share the Model
dave |
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| pekar |
Thanks, I've uploaded it. A search for DelSol should locate it.
Pekar |
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| pekar |
Construction tips.*
1. Tune up your tablesaw. http://store.thesawshop.com/catalogue/docs/tune-up.pdf
2. Rip the bottom and backs first at 5"wide.
3. Crosscut them oversize, and label each. Check your parts for square. Square parts fit together much better!
4. Rip the sides at 8 1/4".
5. Crosscut the sides at 9" (you can use the rip fence here). Label them and draw lines on the inside face indicating where the back and bottom meet. Use a square and be precise. Check that these parts are square.
6. Rip the top and face slightly oversize at 6 3/4"
7. Locate and cut the port hole in the bottom. This is either 2" or about 2 3/8" dia.. Round over the bottom of the port with a router only if butting the PVC to the inside of a 2" dia hole (1/4" bit).
8. Draw on the inside of the back where the bottom meets it 1" up.
Test assemble one side, back and bottom. if happy with the dimensions, test clamp these three parts.
Once happy, I like to assemble this much and let it dry overnight, before adding the other side and top. This method is more time consuming, but avoids fasteners like nails, screws or splines.
The lines you drew act as glue lines now. Square assembly is crucial. Jorgenson bar clamps work best. I like to dry clamp a square scrap piece to the face and bottom to make sure that dries square. I'll try to upload a picture ofthis setup next time I build a set, which could be a while. It is a maze of clamps at this point!
9. Remove clamps, test fit the other side and top again. If happy, rip the top to final dimension and glue on the side/top. I leave the speaker on its side with a HEAVY weight on top to hold the side on, and clamp the speaker top.
10. When dry, test fit the face, cut the face to final dimensions, cut the holes. For the bottom slot port, I use a 1" bit to cut the curved sides, then cut across with a high quality jigsaw. Drill in a little from each side to reduce tearout. Round over the slot port.
11. Drill and install speaker wire. Seal with silicone. Use something lighter than lamp cord. Monster cables are not recommended at these power levels. Round the edges of and glue in the PVC port. Install carpet pad damping on inside of box.
12. Chamfer or round over the INSIDE of the speaker hole. Make sure to not remove material required by the speaker screws. Attach face. When dry, round over the right and left sides of the face with a router.
13. Insert tasty beverage.
14. Install speaker. Predrill holes slightly smaller dia than the screws.
I solder the wire to the speaker, leaving enough slack to remove it and set it on top of the speaker for tweaking. Solder connectors or tin ends of wire to connect to amp.
15. Test and tweak! Keep the screwdriver out of the cone!
16. Remove speaker and apply finish if required.
These are not the most efficient instructions, but are designed to ensure the greatest chance of success, especially since many won't be using professional grade equipment.
For quick prototyping, I use a finish nailer, and assemble in one shot, without clamps.
I love PL premium construction adhesive for speaker assembly. It is a no odor, polyurethane construction adhesive that comes in caulk tubes. It expands slightly, like Gorilla glue, but has a lot more body. I buy it at Menards, I don't know if it, or a similar product is available at your local home center or not.
Please let me know of any similar products you've found. So I can recommend them to others. Polyurethane is the key word here.
*I haven't tested these directions. There may be errors and omissions. Be safe! Please check down the thread for possible updates.
Pekar |
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| kristleifur |
| Thanks for the tips! These will be useful for any one of us noobs, whether we're building Delsols or not. |
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| blumenco |
I have an old junky table saw in my kitchen that I use from time to time. It could probably use a tuneup. it would make my projects look better too no doubt.
course, I am usually just aiming for an end sonic result. I have eventually found that selling my experiments to friends at modest prices allows me more feedback, a little cash to cover parts expenses, and keeps the clutter down in my apartment.
so getting a table saw right is important for me right now...
Clark |
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| pekar |
I've done a little research at Home Depot.
They sell PL premium construction adhesive, my favorite glue. It is $3.89 in the glue section. It comes in a caulk gun tube.
They also sell removable weatherstripping called "Seal and Peel" made by DOW it's $4.29 and is in the same section. I use this both for speaker gasket, and to temporarily put a face on a cabinet for testing that I'd like to disassemble later.
2" PVC is available in 2' lengths for only $2.69 |
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| doggy |
Very interesting,
I wonder how this driver would preform in a linear array of 3 or 4 units per side?[grouped in the same cab.] parts are priced right. Any opinions? and can it be modeled? :D |
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| Spasticteapot |
| Does anyone know how well this speaker would work if built out of, say, acrylic? |
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| chrisb |
| quote: | Originally posted by Spasticteapot
Does anyone know how well this speaker would work if built out of, say, acrylic? |
Acrylic sheet as is "plexiglass", or the acrylic based mineral filler laden solid surface materials ( i.e. Corian, Avonite, etc.) ?
Due to the cost and fabrication intricacies, I've yet to hear any DIY speaker made from the latter, My only audition of a commerical (Full range) product was quite underwhelming . |
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| pekar |
| Corian has been successfully used in a similar design. I think thick acrylic could work, but I don't think it would outperform 3/4" MDF. |
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| fusion |
pekar. I am actually going to constuct these speakers.
any chance of a parts list such as wood sizes n stuff, much appreciated. |
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| planet10 |
| quote: | Originally posted by pekar
but I don't think it would outperform 3/4" MDF |
I don't know about that... IMHO MDF is not a great speaker building material (unless you are a speaker manufaturer trying to keep costs down)
dave |
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| Harderror |
| quote: | Originally posted by planet10
I don't know about that... IMHO MDF is not a great speaker building material (unless you are a speaker manufaturer trying to keep costs down)
dave |
I don't know about that. Some of the most expensive speakers in the world use MDF. I believe the Wilson Watt Puppys are partialy MDF. I agree with you that MDF is generally hard to design with and I have not gotten good results with MDF but many extremely high end speaker designers are using it. In the end, these guys are not worried about an extra hundred bux for wood in a 40,000 dollar speaker.
Tom |
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| doggy |
| Another reason mdf is used is because of dimensionl stability and milling qualities. :) |
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| GG |
For a sub, I prefer to use MDF.
Plywood seems to work better for fullrange units.
However, I have not noticed anything ugly with MDF. |
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| LaserL |
Hi Pekar
What is the internal volume of the box?
And what is the tuning frequency?
I live in the part of the World were we use the metric system, so inches is not my strong side.
Thanks. |
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| Spasticteapot |
| Actually, I was hoping to use acrylic because it's easy to work with - I'm no good with wood, but it's not hard to bend a single sheet into the right shape. |
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| gychang |
can I have hands up on how many people have built this?, looks interesting and some seem enthusiastic.
gychang |
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| Spasticteapot |
The NS3-194-8E has a nasty treble roll-off.
Perhaps this could be corrected with one of the Dayton Neo tweeters ($5) and a capacitor? |
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| gychang |
are we all talking about actually a speaker only one person has built?
gychang |
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| toolkit |
| Well I'm planning to try a pair - trying to find a source for the drivers in Europe before I order from madisound. They have quoted $30 shipping on one pair or $40 for three pairs if anyone in the UK is interested in a pair we could combine. |
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| gofar99 |
Hi, great looking project. I am about to do something similar with Fostex126e drivers. I like the front treatment of the boxes. Along with a K-12, I use Sonic Impact Super T amps for driving my subs and when the K-12 is out of service on my main speakers. I have both regular T amps and the Supers. The difference is huge. Better bass, cleaner mid and top bout doesn't lose that detail and almost tube like sound. I understand that Sonic Impact is bust, but places like Parts Express still list the amps. $US139 isn't real cheap, but they are hard to beat at the price.
Good listening
gofar99 |
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| planet10 |
| quote: | Originally posted by gofar99
I understand that Sonic Impact is bust, |
I don't know that that is the case, but with tripath dying or dead, they will be scrambling to scare up power-amp chips where they can and looking at designing a new amp.
dave |
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| Fast1one |
| How do you think these would fair with about 3-5 watts? Just curious as I have such an amp laying around (nothing special). |
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| gofar99 |
Greetings,
Probably fairly well. Th K-12 I use has been rewired to ultralinear and probably only delivers that and I find it quite adequate for the much less efficient speakers I use (87 dbw). My sense is that for most listening we only actually need about a watt and the rest is for headroom (peaks). IMO as long as the amp can handle the peaks Ok the sound will be fine. That is part of the reason a K-12 is my main amp.
Have a great day
gofar99 |
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| Fast1one |
| Yeah its only for my computer speakers for a small room...awesome maybe Ill go ahead and try this project! |
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| pekar |
The latest Delsol evolution.
amp6 , custom NIMH pack, 10 lbs. Loud, efficient, small, more to come.
I'll have a tutorial up within a month, I hope. |
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| Fast1one |
| Does the front baffle HAVE to be 1/2 inch or can it be 3/4 inch? |
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| pekar |
I know this is going to cause difficulties for some.
3/4" material is going to need some relief on the backside.
If you have trouble sourcing 3/8" to 1/2" hardwood, I guess I'd have to recommend trying dense 1/2" ply, or MDF for the face. |
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| planet10 |
I'd expect for something portable like this, 1/2" BB would be the choice because it is light, yet still better than 3/4" mdf.
dave |
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| Fast1one |
| One more thing before I finally build these things...Does the front have to be curved like that or is it just for aesthetics? Can it be like your boom box is? Just asking for simplicity of build... |
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| bjorno |
| quote: | | Ignore the fs, it does far better than the numbers indicate. |
Hi,
I just looked at this implementation with the Aura 3 inch driver and came to the conclusion that with the information given, no one but the designer of this speaker can be sure if it’s a good design regardless of what is said here above.
I’ve designed with more than 100 of those drivers in many different enclosures but I never came up with a dimensioning that is even close the suggested one.
There is a spread in sample data that should make difference if used, but I believe not as severe to be a coincidence and fitting this Delsol-box.
This box suffers from a huge peak close to 90-100 Hz with my T/S data and is under dampened with no control from the port back to the driver, thus the driver is as in IB condition.
I’ve tried both port lengths it makes no difference.
When tested in a ported box simulator, MJK: s ‘of course’ and only the box volume, driver position and the inner port were simulated, I immediately saw that the box must ’?’ be defined in a sort of very simple reflex box simulator because now the port was controlled as should be, but still severely peaking at about 110 Hz.
By the way, there is no way to use programs like WinISD or similar to predict the Delsol speaker other than what I just commented in my reflex box simulation test.
As no simulations or measured performance is shown anywhere ‘?’ for this speaker project other than hearsay.
| quote: | | One more thing before I finally build these things...Does the front have to be curved like that or is it just for aesthetics? Can it be like your boom box is? |
This question, I think is quite superfluous and I recommend; don’t build this box until measured FR data or a simulation with all simulation data is available.
Is there any possible rescue to implement?
Yes, by either use driver acoustic dampening or by the use of derived closed or reflex box methods like: closed box leakage dampening or dampened box/dampened vent and even the use of a BBC method, the double cavity vented box where if an acoustic resistance is the box divider, no notch will occur on the FR curve.
b |
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| Fast1one |
I wouldn't jump to conclusions with the T/s parameters alone. After all, the manufacture states that there is a tolerance of +/- 25 percent...or atleast that is what has been discussed in this thread. I dont like using graphs for all my conclusions. I rather go off someone who has actually built the enclosure and go off of his opinions....A simulation can only go as far as the accuracy of the parameters...
Im still going to ahead and build them, pending the question is answered by the original designer. It seems like a fun project to have at the office... |
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| pekar |
Fast1one-
The front is curved for aesthetics. Use 1/2" BB ply for the front baffle, planet10 is right MDF is inferior here.
Bjorno, thanks for your input.
From the first post in this thread -"I present this as an experimental starting point, and welcome suggestions."
I don't design by simulation. I build and test.
In designing this driver, I reduced box size as much as possible, while maintaining a good sound. Using larger boxes can give better results with this driver.
While far from a severe problem, You are correct this box may benefit from more damping. I'll let everyone know when I find an improvement that doesn't kill the life that the sound in this box currently has.
This projects' cost is extremely low. My hope is that it will give potential enthusiasts something simple to start and learn with, possibly sparking in interest in more advanced projects.
I think this project fills a need that isn't addressed. Namely a simple bookshelf size fullrange speaker that isn't compromised by crossovers and filters, and is a good match for t-amp, and low watt enthusiasts.
Audio systems are getting smaller. The high end hasn't really recognized this yet.
Pekar |
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| okmrbh |
Quick question:
Would .5" solid oak work for the front instead of maple? I'm having a hard time sourcing that size maple but the oak is around and on sale!
Thanks |
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| gychang |
I have TangBand W3-871S laying around, can this be used?
what adjustment will I need?
thanks,
gychang |
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| pekar |
Oak should work fine.
I did extensive testing and comparison with the TangBand W3-871S, and found that they never worked in the same cabinets. I generally preferred this Aura to the W3-871S.
I did really like Cyburg's needles with the W3-871S. That's the most impressive 3" I've built to date. |
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| okmrbh |
| Well I just finished making the cabinets! Just waiting for the speakers to arrive now, hopefully they wont take too long. |
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| shallbehealed |
Finished mine this afternoon. The speakers are wicked bright, but I left them on when I went out to dinner and I can already hear them chilling out a little bit.
I'll post a full review when I feel that the drivers are broken in. |
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| okmrbh |
| I just put mine together and I'm really impressed with them! Thanks very much to "pekar" for providing the instructions and going through all the R&D in putting these together. |
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| shallbehealed |
| quote: | Originally posted by shallbehealed
Finished mine this afternoon. The speakers are wicked bright, but I left them on when I went out to dinner and I can already hear them chilling out a little bit.
I'll post a full review when I feel that the drivers are broken in. |
decent sound, but not nearly as good as i was hoping for. maybe for use as a desktop speaker, but certainly not useful as a small room bookshelf. |
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| pekar |
Hi Shallbehealed,
Can you be more specific?
Posting pictures of your speakers and setup might help us to suggest things that will improve the sound.
Of course, there's only so much you can expect from a 3" driver!
Hi okmrbh,
I'm glad you like this design.
We'd love to see pictures of your build, and details on how you're using this speaker as well.
Pekar |
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| okmrbh |
Hi Pekar, I'm happy with the way they turned out & sound, especially considering these speakers along with the tube amp I built to go with them was my first attempt at building this type of gear and I rushed it abit in my excitment to get everything done!
I'm using the stereo as a portable system that I hook up my small am/fm & shortwave eton e-5 reciever, it's has a line out jack that goes right into the inputs on the amp. Another use is to hook it up to my computer, or the kids for their ipods, cd players etc.
I still have to work out a few more details for the amp like making a better one piece ventilated lexan cover for it as the current two piece is a temporary fix.
I hope the picture shows up as I'm new to this posting stuff. |
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| gmilitano |
| quote: | Originally posted by shallbehealed
Finished mine this afternoon. The speakers are wicked bright, but I left them on when I went out to dinner and I can already hear them chilling out a little bit.
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| quote: | Originally posted by shallbehealed
decent sound, but not nearly as good as i was hoping for. maybe for use as a desktop speaker, but certainly not useful as a small room bookshelf. |
Sounds like you need a BSC. |
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| gmilitano |
| quote: | Originally posted by okmrbh
Ok let me try again.
 |
Posted for okmrbh.
What you need to do is use "Attach file" located above the "Submit Reply" and Preview Reply" buttons.
These look great!!! |
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| gychang |
| quote: | Originally posted by gmilitano
Posted for okmrbh.
What you need to do is use "Attach file" located above the "Submit Reply" and Preview Reply" buttons.
These look great!!! |
I don't care how it sounds, it LOOKS good. gychang |
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| okmrbh |
Thanks guys, I tried attaching the picture in that way but it still wouldn't work? Anyways thank you gmilitano for posting it up for me. I'll try again and see if I can get it to work as it seems to have accepted it now...
Great now i get a message that the file is too big! |
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| Cal Weldon |
| Try reducing your pic to 100K or less. |
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| gofar99 |
Hi OKMRBH, Very nice construction. You are a craftsman after my own heart. Half of my stuff looks like crate wood. A question, the amp is clearly a K-12. Is the cover screen material? If so what kind? Great wood working.
Good listening
gofar99 |
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| okmrbh |
Hi gofar99, The amp is actually an aes K-502 model I think it's essentially the same as a k-12. The cover is made from lexan ( a type of plexiglass) i mentioned earlier it's a temporary two piece as I'd like to make a ventilated one piece next week some time. When i first built the case the front portion was rounded too keep the lexan away from the heated tubes but i had a hard time getting the lexan to have a flush fit with that rounded shape so I cut it on an angle.
Incase your wondering thin lexan is fairly flexible when heated with a heat gun you just have to be careful not to overheat it as it well bubble on the surface and spoil the appearance. I ran out of time trying to make the new cover so just made a quick two piece (top & front) for now.
Thanks for the kind words about my woodworking, It's amazing how an angled, low resolution picture can make almost anything look perfectly acceptable! |
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| shallbehealed |
| quote: | Originally posted by gmilitano
Sounds like you need a BSC. |
Grabbed the MJK pdf from your sig, but anyone know what the Lvc is for this speaker? |
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| gofar99 |
Hi okmrbh, You are correct. The 502 and 12 are clones. They change the name when you get it from some companies. On the Lexan face, have you considered having a lexan front and a screen top. I have covered a few things with metal screen such as hardware stores sell for kick plates on the lower part of screen doors. It is usually light guage metal and comes in many patterns. On piece is good for several projects. It is paintable also. IMO If you made a flexible fabric hinge at the top of the lexan and a painted metal cover over the top of the amp it would look kind of neet. A different possibility might be to use a fan from a computer and force cooling air into the case. Perhaps from the bottom with small vents near the top. It might allow you to still use a clear top and not have a melt down. Beware however of the possibility that some fans generate electronic noise that could crud up the sound. Keep posting the photos, it's good to see quality work.
Good listening
gofar99 |
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| okmrbh |
Hello gofar99, thank you for the good ideas.
Yes I was thinking of something like that and actually checked a few hardware stores to see if there was anything but I didn't see anything at the time too bad I didn't know about your kick plate material earlier.
My initial idea was just to build the kit on the supplied pine board to see if it would actually work, then build a fancier case for it later. I was uncomfortable with the idea of leaving the kit open like that so I picked up a few pieces of cheap pine board just to sort of box it in. Then I thought about putting a Plexiglas cover over it because I like the look of the tubes. So what started out as a temporary case looked better than I expected when the stain was applied.
I plan on drilling and or milling vent slots on my permanent cover for ventilation I have vent holes on the side and bottom of the case as well, it's still a bit experimental, right now my priorities are/were
1: will it work?
2: will it sound good?
3: will it melt down or catch fire!
4: what can I do for improvements?
So right now I'm hovering around # 3 & 4. Funny you mention fans I was thinking about it for my fancier case but being new to the audio diy I thought I should stick to the basics for now. |
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| gofar99 |
Hi okmrbh,
My K-12 runs pretty hot. I'm sure that if I covered mine with lexan, it would only be about half an hour and I would have a melted goo pile followed, shortly by a fire or such. I originally built a cover for mine with the kick plate material and it looked good. (unfortunately I didn't take a photo of it) I eventually broke down and bought the case from S5.
Good listening
gofar99 |
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| okmrbh |
Hi gofar99, I hope to finish up my new and improved cover tonight. Yeah I'm a little concerned about the heat but hopefully my cover will work, if not I already have a few ideas...
You said you have a k-12 do you like it? Are you going to build the delsol speakers I'm really impressed with them and did not find them that difficult to build at all. If you want I could send you some tips that I found helpful, especially if your like me and lack some T.T.S ( tools, time and skills)!
It's a shame you didn't get a picture of what you had I would have liked to have seen it. |
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| gmilitano |
Hi Barry,
The K-12 / K-502 amps run hot. Suspecting DC in the AC mains, I tried the DaBlok, but it did not help with temperature. The tubes simply put out a lot of heat and the transformer is very near rated capacity so it also adds some heat.
The K-12 kit sound is very impressive, even more so when you consider the low cost.
Cheers,
Gio. |
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| gofar99 |
Howdy again, A number of us have K-12s and love them. With certain modifications they have an aluring sound quality. How far you wish to modify the amp is up to you. It is not a complicated process. There are a number of variations on the same theme for the mods. I suggest you visit the www.diyaudioprojects.com site for some examples. There are at least three different variations of mods there. I have one, the host (who has also replied to this thred ) has at least one as does another contributor to the site. There are several links to variations not shown on the site. Any of us will be glad to assist. Email me direct if you chose. I also suggest that we shift the posts to the tube amplifier section as we have wandered away from full range speaker systems.
Good listening,
gofar99 |
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| pekar |
That is a very handsome setup, okmrbh, congrats.
My personal goal is to optimize the sound via mechanical, rather than electrical modifications, but feel free to post any modifications you guys come up with.
I'm still playing around with the damping. My original speakers have thick felt padding on the back wall of the speaker only. I have
found this is too bright, especially for close proximity listening. I
have since added the same padding on one side wall as well. The
response is flatter, but the bass is now somewhat reduced.
I have not had any success with box stuffing. |
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| okmrbh |
Hi pekar thanks for the nice words, I'm new to this so I'm going to rely on others for tweaking ideas. One thing I was thinking about would be puttig duct seal on the speakers back frame, looked like a quick & easy to do, do you think it would make a difference?
I dont really find the speakers overly bright ( I think this means stronger on the higher freqs?). For me, I'm just judging them by how well they reproduce the sound of the instruments. My ear tells me that these do it quite well as long as the original recording was done well. Drums, guitar and piano all sound quite good.
For back dampening I used a piece of industrial "rough top" conveyor belting basically it's a piece of rubber conveyor belt smooth on one side & rough on the over sort of looking like a 1/4" thick floor mat.
Thanks again for sharing your plans with us & keep us posted on any tweaks you come up with. |
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| magurer |
Hi guys,
getting back to the DelSol fullrange speakers, I've build the cabinets but now I am trying to get some information on where to put damping? Back, front, everywhere or non even? What type is suggested? Does anyone have some input on this topic?
Thanks,
Mag |
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| planet10 |
| quote: | Originally posted by okmrbh
One thing I was thinking about would be puttig duct seal on the speakers back frame, looked like a quick & easy to do, do you think it would make a difference? |
Duct seal usually makes a difference. What does the back of this driver look like?
dave |
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| planet10 |
The baskets look pretty flimsy and the magnet assembly looks the same as the lower efficiency Aura i've had. If you take the approach of building up the back of th driver to streamline it, the damping will be a side effect. The basket legs won't support all that much ductseal and i wouldn't bother ther. Some of the latex paint-on damping might be a good bet here (used in boat building, i have some called SR-2000).
Now with these we have to consider the gotcha... neo motors do not tolerate heat well... so you probably don't want to impede the cooling of the motor assembly. This means leaving the motor assembly open to the air (ie duct seal in this case has a big negative). So you would need to get creative.
dave |
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| okmrbh |
| Thanks for the reply Dave. I think I'm going to just leave it be for the time being as I find they sound good right now. |
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| bjorno |
| quote: | | The baskets look pretty flimsy |
Yes and I also don’t think there is any need for reinforcing the basket, colouring effects from vibration is negligible if the driver is glued hard to the baffle, but worse and detectable near x-max if only secured with screws caused from the ‘flimsy’ small flange.
b
1(1) |
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| planet10 |
| quote: | Originally posted by bjorno
colouring effects from vibration is negligible if the driver is glued hard to the baffle |
Not in my experience....
You can achieve better coupling of this basket to the baffle by rear mounting them... it complicates things somewhat, but at least with the concave Auras i have is worthwhile.
dave |
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| bjorno |
Hi Dave,
Yes, also the Aura NS3-194-8E drivers are meant to be rear baffle mounted and are easily bent if applying too much of torque.
I have only measured one a 25 driver square besselarray with an accelerometer attached to the driver frames, one by one, which had this problem; all were front-mounted in separate sealed compartments with a 2 mm polyurethane gasket.
A guitarist user, who discovered this when testing, mentioned that a weird sound was appearing only at higher levels when playing chords. I first thought this could be anything but…
Borrowing his guitar-amp I found 2 of the malfunctioning driver’s spectral vibration signature differed a higher volume levels, I dismounted both and replaced with new ones.
For one driver the problem was gone but it remained for the other.
There were no air leaks but measuring from screw hole to screw hole the frame flatness with a vernier caliper, I found at most flatness differences of 3/10 of an mm for the drivers tested as faulty that were mounted in the same hole
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When disassembling more drivers all had slightly bent frames, a 1/10 mm or so.
Later I used an adjustable torque screwdriver to avoid bending the very soft steel of the frame and by epoxy gluing the frame rim.
So far I’ve been mounting a hundred of these drivers with success and have still more than a hundred left over for future projects that I consider only mounting to the rear of any baffle and to avoid the gluing.
b |
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| planet10 |
That is a way cool application... can you post a bigger picture?
dave |
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| bjorno |
The 25-element besselarray again, before cabinet corners, handles and aluminium profiles were attached.
Box made of 12mm and 7 mm void free heartwood veneer of pine, harder(no splint-wood) and stiffer than of birch and the baffle is 12 mm HDF (not MDF).
b |
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| okmrbh |
Hi bjorno, that speaker obviously goes up to eleven!
Is it part of a set? How does it sound? It looks VERY impressive, how did you cut the holes for the speakers and stay that consistent? |
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| pekar |
I've been front mounting, back mounting sounded awful.
You'd need a very thin faceplate for it to sit properly.
I seal the frame with removable weatherstripping mentioned earlier, screw it down, and trim the excess when it dries. Don't use too much!
I haven't done anything to beef up the basket yet. it may look flimsy, but relative to driver size and watts, it's pretty strong. |
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| cfurrow |
Pekar,
Maybe I missed in your directions these details, but exactly where do the holes need to be cut for the speakers and for the port? Attached is a pic. Thanks! |
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| gofar99 |
Greetings, Nice work and clever thinking. Living out here in the desert, the sun is intense and a similar solar array I have delivers an amp at over 16 volts. A cheap fix to potential over voltage problem is to use either a 12 volt zener diode or any of several three terminal regulators to keep the voltage in check. A modest 12 volt gell cell across the solar array's terminals will also do the job and provide power when the sun goes behind the clouds. Again good project.
Good listening
gofar99 |
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| ped |
| quote: | Originally posted by pekar
For those who may have missed it, DelSol has morphed into a solar powered boombox.
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Any chance that you can post more details on your boombox, especially the cabinet? |
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| gychang |
| quote: | Originally posted by pekar
Oak should work fine.
I did extensive testing and comparison with the TangBand W3-871S, and found that they never worked in the same cabinets. I generally preferred this Aura to the W3-871S.
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Do u think it will work with W3-593S? (on sale at PE).
gychang |
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| pekar |
| quote: | Originally posted by ped
Any chance that you can post more details on your boombox, especially the cabinet? |
This cabinet is essentially two DelSol's turned bottom to bottom with a plate in between. Cabinet volume has been increased to accomodate the amplifier.
I might get around to providing cabinet plans eventually, but I have too much on my plate at the moment.
| quote: | Originally posted by gychang
Do u think it will work with W3-593S? (on sale at PE).
gychang |
Probably not, but the Aura 299-015 (also on sale at PE) might! |
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| ped |
| quote: | Originally posted by pekar
This cabinet is essentially two DelSol's turned bottom to bottom with a plate in between. Cabinet volume has been increased to accomodate the amplifier.
I might get around to providing cabinet plans eventually, but I have too much on my plate at the moment.
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Thanks, I may just use standard DelSols and then a thin box hinged across the top to act as a flip down cover/electronics housing. In your picture gallery is a speaker using two drivers per side, could you please provide basic dimensions/porting for those? Looks like a way to squeeze a bit more bass/efficiency out of these things :cool: |
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| pekar |
That was an unsuccessful experiment that eventually led to the Delsol design.
Here is what led to that two driver design-
http://www.timn8er.com/css_elf_1.htm
In the end, I decided I preferred a single driver solution.
The only application I found that got enough bass out of the W3-871 for me was Cyburg's needle which didn't lend itself to a boombox format.
Pekar |
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