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John W
05-21-2005, 11:46 AM
I am putting together a driver lineup for a 3-way.

Here is what I have:

E145 15in Woofer

1200hz Smith Horn

076 like tweeter



The 1200hz horn is from this thread:

http://audioheritage.org/vbulletin/showthread.php?t=5454 (http://audioheritage.org/vbulletin/showthread.php?t=5454)



The 076 horn is something I have been working on. I have a 076 in my 222 disco and like the sound of them. I wanted something to mate nicely with the walnut smith horn, so I decided to copy these in walnut. I doubted my ability to match the oval, so I carefully measured and copied the inside and outside curves from my 076. I then reproduced these two profiles and mitered together a rectangular horn of the same dimensions.

This is built on a 2402 driver so I also had to turn out a phase plug and housing on the lathe.

I was fairly careful in my measurements of the original.

I have tested them out on top of the L222, and they sound the same from what I can tell.



I have located a place where I can take these and the smith horns and have them measured in a professional facility. But it is a little bit of a drive so I want to get a crossover together and test everything at once.

John W
05-21-2005, 11:47 AM
I am currently planning to bi-amp the speakers, with a charge-coupled n333 for just the mid and tweeter. I have a variable active crossover for the woofer, and plan on cutting this in an 850hz. The crossover also has a high pass section that consists of a switchable bank of 4 .027uf capacitors that together with the impedance of the amplifier give a nice low-noise cutoff.



The box design is around 4.25 ft3 with curved sides, roughly 20 x 40.



I am just getting started on the box and the passive crossover.

Does anyone have any recommendations, or see any problems in the design. Critical comments would be greatly appreciated.

John W
05-21-2005, 11:49 AM
Also, should the tweeter go vertical or horizontal? I have made it square just in case I need to experiment.

Zilch
05-21-2005, 12:04 PM
Also, should the tweeter go vertical or horizontal? I have made it square just in case I need to experiment.Not sure, probably vertical. What I DO know is that it is very beautiful. :applaud:

You could run some measurements with an SPL meter to see what the polar dispersion pattern is....

yggdrasil
05-21-2005, 12:07 PM
John that is a fantastic work you have done. :jawdrop:

Just a comment on placing the Smith horns. I had mine lying on top, for some days. At that time my wife and I had an understanding that this would last a while. After 6 days that while was over (my plan was 2-3 months) and I immediately had to rebuild the baffle on my speakers to make place for the Smith horns. I have not had the time to make it look at all presentable, but I have been listening. They sound even better when mounted inside the cabinet. Probably less vibrations.

pmakres1
05-21-2005, 12:11 PM
IMHO, the tweeter should go vertical to mimic the dispersion pattern of the 076.

This is extremely beautiful work!!!!!!! :applaud: :applaud:

Very best regards,

Peter

spkrman57
05-21-2005, 01:59 PM
Can't wait to see the finished product and hear your evaluations on it.

Ron

John W
05-22-2005, 07:24 AM
Thanks for all the input. I will get busy on the cabinets and crossovers and keep you posted.

paragon
05-22-2005, 09:13 AM
Fantastic good looking wood horns and phase plug !!
Excellent drivers !! Very good work.:D



Eckhard

K145 (black)+ E145(red) in 150 L Reflex with same duct.

MatthiasA
05-22-2005, 09:29 AM
very good :applaud:
very good :applaud: :applaud:
very good :applaud: :applaud: :applaud:

what kind of wood is it ?

walnut oder something else ?

greeting Matthias

4313B
05-22-2005, 10:08 AM
Outstanding! :yes:

John W
05-22-2005, 09:06 PM
Yes, the horns are walnut.

I am still considering different ways to make the box. I want to curve the sides. Has anyone kerf bent mdf (a bunch of vertical kerfs all but about 3/16 of the way thru), then back filled the kerfs with bondo, like for cars, perhaps reinforced with fiberglass cloth?

Steve Gonzales
05-22-2005, 10:20 PM
That is some beautiful work, WELL DONE!!!!!:applaud:

bbrown
05-23-2005, 06:23 AM
Have a look at this thread:

http://audioheritage.org/vbulletin/showthread.php?t=4229

He is making an S2600, and is kerfing a bunch of mdf for the horn.

MatthiasA
05-23-2005, 06:56 AM
Have a look at this thread:

http://audioheritage.org/vbulletin/showthread.php?t=4229

He is making an S2600, and is kerfing a bunch of mdf for the horn.


yes that's me!
you get it on better selected wood stores!
in Germany "geschlitzes MDF"

i do every round things with it!


then back filled the kerfs with bondo, like for cars, perhaps reinforced with fiberglass cloth?

what is bondo ?
is it like 2 component putty mass?
i prefer without fiberglass because you can better sharp it

fiberglass in putty mass is :bs: you cannot good sharp


greetings Matthias Asselborn

MatthiasA
05-23-2005, 07:09 AM
to get rid of the berks !

you can glue the berk sides !
then you have on both sides no berks !!!!

look at my picture
i made this for you !

bbrown
05-23-2005, 07:17 AM
Matthias,
Yes, Bondo is used in auto repair and for MANY other things here in the U.S. It uses a catalyst (i.e. a two part material).

http://www.bondo.com

They have fillers, glass clothe, tons of stuff.

btw, nice job on the cabinets. The Everests will be cool.

Bruce

John W
05-23-2005, 07:25 AM
Thanks for the good info, I thought I remembered seeing something similar here, but couldnít recall where.

MatthiasA
05-23-2005, 07:44 AM
did you mean this link?
http://www.audioheritage.org/vbulletin/showthread.php?t=4229

ive post a lot of pics during the S2600 rebuild
if you need any information about DIY and how to do - ask me!

you wooden Horns looks very very good!
i could not make it better than you!


greetings Matthias

Uncle Paul
05-23-2005, 09:45 AM
I am still considering different ways to make the box. I want to curve the sides. Has anyone kerf bent mdf (a bunch of vertical kerfs all but about 3/16 of the way thru), then back filled the kerfs with bondo, like for cars, perhaps reinforced with fiberglass cloth?
Kerfing the MDF will work, but you might want to consider using bending stock to make the curved sides. Bending stock is a type of plywood where the grain all runs in the same direction. Almost any building supply outlet can order it for you.

Mr. Widget
05-23-2005, 10:25 AM
I want to curve the sides. Has anyone kerf bent mdf (a bunch of vertical kerfs all but about 3/16 of the way thru),...

I am in the process of building a pair of curved walled three-ways myself... ironically even though I have made several wooden horns, this project will not feature any wooden horns.:(

I know of several types of bending woods used for curved laminations. There is bending poplar, which comes in thin sheets with all of the grain oriented for easy bending. There is wiggle wood, which is two plys of luan on either side of a flexible membrane, and then there are the pre-kerf'd MDF panels. You could always kerf your own, but what a pain that would be...

For speakers I would suggest the pre kerf'd MDF. Here are two sources.

http://www.neatconcepts.com/neatform.htm

http://www.outwater.com/

(Page 83 of their Architectural Products catalog)

Widget

macaroonie
05-24-2005, 12:32 AM
give these guys a try http://www.aitwood.com/index.htmlthey have lots of ready formed birch ply components :)

Datubie
05-24-2005, 04:32 AM
Very pretty! You should make & sell them!:applaud:

John W
06-06-2005, 09:21 PM
A quick progress update:



The boxes are coming right along. I cut the kerfs myself with the thinnest blade I had. It didnít really take too long since there are four sides and you can flip the sides around. So it is 8 cuts before you have to reset the fence.

I did some trials and determined I could get bye with kerfs each inch.

I bent and screwed them onto the bracing, top and bottom. Then I used fiberglass reinforcing that is sold for drywall taping. This worked really well. It is sticky on one side, and is porous enough to let the bondo through and into the cracks.

I am almost ready for paint and veneer.

I have a sheet of paperbacked quartered, walnut veneer on the way.

Here are a couple pictures of the boxes in progress:

John W
06-06-2005, 09:22 PM
I have also assembled the crossovers. These are using the charge-coupled n333 schematic. The caps are Axon. This is just the tweeter and mid. I am bi-amping so the woofer will be runing flat-out.

Mr. Widget
06-06-2005, 09:56 PM
Your speakers are looking very nice... I can smell the Bondo from here!

Pretty funny, we are running a race and didn't even know it. I hope to have mine playable late tonight or tomorrow... they are further along than this photo from a couple of days ago. I won't be veneering mine for a while. I want to make sure they're keepers first.

Widget

John W
06-07-2005, 07:21 AM
Very nice.:applaud:

I like your bracing.
Is the tweeter going to be sealed within it's own box above the woofer, or is it all sharing the same space? Its hard to tell from the photo.

Mr. Widget
06-07-2005, 10:14 AM
Actually in their unfinished forms I like yours better! I did get mine wired, fiberglass lined, and loaded with drivers last night. I knocked off about 1:00. I'll power them up tonight!!!

The tweeter is not in a separate chamber. The vertical bracing runs through the center of the bass cabinet. If I had continued it at the top of the bass cabinet it would run into the back of the tweeter so I split it and ran one brace on either side of the tweeter. I plan on popping in different tweeters. At this point it is still a test bed.

Widget

GarMan
06-07-2005, 01:52 PM
John, you said that the woofer and mid will be crossed at 850Hz. I may be taking this too literally, but can a 1200Hz Smith Horn go down that low?

Gar.

John W
06-07-2005, 02:20 PM
I am no expert at this by any means. But my understanding is you tune a horn for a given frequency and then you have some roll-off on either end.

My driver is certainly good to below 850hz and I am hoping the horn wonít drop off too much either. If anyone has any solid information on this I am anxious to hear it.

My active crossover has some variable low pass levels so I can tune it up some if I have a midbass hole.

Iíll let you know once I do some measuring.

yggdrasil
06-07-2005, 03:04 PM
The 1200Hz Smith horns should do well. On an LE-85 with phenolics or titanium dia's the rolloff starts at 5-600Hz.

Mr. Widget
06-07-2005, 04:00 PM
Have you measured that? Here is a curve of a stock JBL 2397 "800Hz" horn. It is decidedly rolled off below 1200Hz. I expect you will get the smaller horn to "work", but I am not sure how well.

Widget

Robh3606
06-07-2005, 04:45 PM
I would be concerned because of the smaller mouth area. You need good loading at least 1/2 octave below your crossover point. If you are using steeper filters you may be able to get it a bit lower. There simply may not be enough horn to load the driver and support a crossover point that low. Only one way to find out!

Rob:)

yggdrasil
06-08-2005, 12:33 AM
Have you measured that?
Measuring on a vocal mic, and a Klark RTA with a calibrated mic. Behringer measurement mic on the way. Still a couple of weeks i think. Got a little sidetracked by a vacation and a pair of Sovereigns...


I expect you will get the smaller horn to "work", but I am not sure how well.

Widget
I second that. Somewhere in the area 800-1200Hz you should hit 2 x fc (cutoff frequency) which could be troublesome.

GarMan
06-08-2005, 07:26 AM
Widget, what driver was used for the plot above? I see the 2328 throat was used, so I'm assuming a 2" exit driver (2440, 2441?)

If that's the case, I'm shocked (and dissappointed) that it drops off so early. I always assumed that a 2397+2" driver can go down below 1000Hz.

Mr. Widget
06-08-2005, 09:27 AM
In those particular plots I was using a TAD 4001. I have also measured JBL 2441s and they are identical in the lower portion of the curve. The TAD's larger magnet and Beryllium diaphragm gives it a slightly flatter and more extended top end. The two plots were comparing a stock 2328 with a custom adapter.

Yes, I too was disappointed.

Realize the scale is relatively expanded, with 5 dB per major vertical division. The response between 1200Hz and 12KHz, which is where I was using the driver horn combo is +/- 2.5 dB... not to shabby really.

Widget

John W
06-13-2005, 07:12 PM
Finished assembly, let the tweaking begin.

John W
06-13-2005, 07:20 PM
So far the sound is fabulous, but I need a little more insight. I am sure twiddling the knobs alot. I hear one track and tune it one way and then say that sounds right, and then on the next track I change my mind and put it somewhere else. I am working on some actual measurements to see what the response is across the bandwidth.
I have found that they can really handle high volume without distortion. This is something I have not experienced at home before

johnaec
06-13-2005, 07:27 PM
Beautiful! What type of wood veneer is that?

John

Mr. Widget
06-13-2005, 07:30 PM
Looks like walnut to me... very nice! You beat me by weeks. Glad to hear you like them.

I have been listening to my project for a couple of days now and am also quite pleased.

Widget

pelly3s
06-13-2005, 07:54 PM
those are absolutely amazing looking. i want a pair lol. now if i only had the talent to work with wood like that

John W
06-13-2005, 08:20 PM
Yes it's quartered walnut veneer from Oakwood Veneer: http://www.oakwoodveneer.com/This was a good supplier, it came right away and was reasonably priced.

Mr. Widget
06-13-2005, 10:22 PM
Very nice sense of proportion and balance. I really appreciate your attention to detail. Very well done!


I am sure twiddling the knobs alot. I hear one track and tune it one way and then say that sounds right, and then on the next track I change my mind and put it somewhere else.

I have found that without an RTA I could spend weeks twiddling knobs before becoming satisfied with a new system's balance. Even now with the help of Clio I can spend several hours tweaking. I find it is best to tweak... listen for a bit and then leave for a few hours before coming back to it... the breaks are really necessary. If you do not have an RTA, I'd strongly urge you to consider getting one or at least borrowing one. There are several units available for under $300... sometimes way under.

Congratulations on a very nice looking pair of speakers!

Widget

Michael Smith
06-13-2005, 11:51 PM
John
They look fabulous!
I'm curious about the placement of the Smith horns on top of the HF units ( the motor is still in the front of my of my car and the rear wheels push it along ) to that end are the highs distinct enough to give you the feeling of height or has this got alot to do with your knob twiddling?
I ask this because I'm about to do my system using the Smith horns and I had intended to mount them in the box with 077 above.
Please keep us posted
Regards
Michael

yggdrasil
06-14-2005, 05:10 AM
Beautiful. Have fun. :D

John W
06-14-2005, 07:10 AM
I'm curious about the placement of the Smith horns on top of the HF units ( the motor is still in the front of my of my car and the rear wheels push it along ) to that end are the highs distinct enough to give you the feeling of height or has this got alot to do with your knob twiddling?
It is a little too early to tell. My current standard for imaging and soundstage are a pair of L222s, which perform this task very well indeed. I need to move the new pair to a more permanent listening space and I will let you know.

MatthiasA
06-14-2005, 07:12 AM
you did a great job! iam very impressed !!

:applaud: :-) greetings Matthias

grumpy
06-14-2005, 08:39 AM
I've found well recorded piano and voice (or other in-situ captured events...
acoustic bass ,kick drum, etc...) can be helpful 'auditioning' tools for balance/weight
in addition to RTA's which can keep you from optimizing for a particular recording -too-
far (can be loads of fun to do that too, but as you mention, it can make the next recording sound like crap).
Helps to know something about the recording (mic location) and have a reference system
(such as your L222's) and/or a great set of headphones.

Projects like these are an inspiration. :applaud:

-grumpy

Mr. Widget
06-14-2005, 09:18 AM
I'm curious about the placement of the Smith horns on top of the HF units ...to that end are the highs distinct enough to give you the feeling of height or has this got alot to do with your knob twiddling?
I ask this because I'm about to do my system using the Smith horns and I had intended to mount them in the box with 077 above.


I have done a fair amount of experimentation with Smith horns and others and John's layout looks just fine. They will image well if he got the horns right and gets the crossovers right. They certainly look great, and with some dialing in I would imagine will sound great to. I have to admit, I haven't yet played around with any of these 1" versions... so that part is a bit of a mystery.

Widget

Earl K
06-16-2005, 03:49 PM
Wow John , Beautiful !

- I'm a little late to this oggling party / seems that I missed at least half the most recent posts . :blink:

- I love everything that you've done with that Walnut exterior .

- Good show . :applaud:

bbrown
06-16-2005, 05:58 PM
John,
Very beautiful work. Are you planning on grills of some kind?

Bruce

aust-ted
06-17-2005, 04:21 AM
John, My belated congratulations on a beautiful piece of work.

It is a pleasure to see the work of a true craftsman as indeed you are.

Regards
Ted

PS Widget's are also looking great.

Jakob
06-22-2005, 01:49 AM
Wow!:applaud:

I'm very impressed with your work. If it sounds half the way it looks, it will be a killer system!

I'm thinking of building a simular system: a 15" driver, a compression driver and maybe a 2405 at top. I could see u are using a E145 and 076 but what are you loading the Smith horn with?

Widget: You are also building a simular speaker. What drivers are You using?

Regards: Jakob

John W
06-22-2005, 07:02 AM
I am using a 2470 driver. This is a one inch driver with a phenolic diaphram. I want to try an LE85 driver also, this is what the crossover is really designed for. Regardless, I am enjoying the speakers very much as is.
I downloaded a 30 day trial of some RTA software and have adjusted the levels of the crossover and L-Pads to give a more or less flat response.

aerohead
06-22-2005, 07:59 AM
Bravo! What beautiful work!
We just moved into a new home so, sadly, I have a huge chore list ahead of me.
Someday I'll be able to set up again to work for the pure pleasure of it without
guilt.

Michael Smith
06-23-2005, 11:19 PM
Hi John
Have just finished my first pair of Smith horns and they are for a good mate,he is using K145-Le85 Smith Horn-077 I will be having a listen early next week,so I will tell you what the!
I think he's using LX10 / N7000 or the Pro variants can't remember,too many wines for lunch, I also think he has your compression driver as well so we can have a good play,his Smith horns are free standing as are yours,only difference is so are his 077,so a playing we will go and I will tell you how it went.
After seeing yours he's keen make a descision one way or the other, ontop or underneath,sounds like a dirty movie
Will keep you posted
Regards
Michael
Ps Have you moved your new babies into the better listening position yet?

John W
07-15-2005, 07:46 AM
Here are the measurements I took off the 076 horn.

John W
07-15-2005, 07:51 AM
I am still enjoying the new speakers. I replaced the phenolic diaphragms on my 2470 horns with 2420 aluminum ones and like the sound somewhat better.

John W
10-19-2005, 06:27 PM
I have since swapped out the 1200hz smith horns on this project with full scale 2397 replicas built from heavy beach-wood driven by 2440s. The 2397 were constructed in the workshop in much the same way as the smaller horns. These mate very well with the E145s, and actually sound much better overall.

I built some grills for the fronts to make the wife happy. Since a nice curve doesn't hold its shape when stretched, the wooden frame was first faced with a fine wire mesh and then covered with the grill cloth.

I have also switched to using an 5234 active crossover with an 18db slope at 800hz to the E145 and a shallower slope to the N333 for the mid and tweeter section, sort of like the 4430 card.

johnaec
10-19-2005, 06:38 PM
Very Nice!! :applaud:

John

Mr. Widget
10-19-2005, 07:12 PM
I have since swapped out the 1200hz smith horns on this project with full scale 2397 replicas built from heavy beach-wood driven by 2440s. The 2397 were constructed in the workshop in much the same way as the smaller horns. These mate very well with the E145s, and actually sound much better overall.I am glad you tried that... I was afraid that might be the case with the 1200Hz horns and 1" drivers... still beautiful looking if not quite the same aesthetic.:bouncy:

Grilles look nice too!


Widget

Earl K
10-20-2005, 04:47 PM
:thmbsup:

- That Beech-Wood Horn looks gorgeous.

- Thanks John for posting your updated pictures . :)

- I love the aesthetics, with or without the grill ( nice fit BTW ) .


:p

Regis
10-20-2005, 08:41 PM
I caught this thread on the fly and I am flat-out impressed as hell! Those are a magnificent pair of speakers. Very beautiful in appearance and I'd like to add, very "JBL" like.

Jakob
10-21-2005, 02:34 AM
John,

thank you for your response to my post reg. an E145/2441 crossover. I did found the n333 schematic but not the biased one, that You seem to use.

What volume and tuning do your woofer enclosures have.

Thanks: Jakob

John W
10-21-2005, 07:48 AM
Thanks for the kind words.
Here is the link to the n333 schematic that I used for the tweeter and mid.

http://audioheritage.org/vbulletin/showthread.php?t=166&page=1&pp=15&highlight=l300+charge

The boxes are approximately 4 - 4.25 ft3, and I stuck with the JBL recommended tuning of 40 Hz. Two 4" diameter ports each having a 6.5" duct.

yggdrasil
10-21-2005, 08:40 AM
Beautiful work John.


Enjoy.

spkrman57
10-23-2005, 07:14 AM
What if JBL could come out with this as a available product. They could make a limited production and list it as a retro-vintage special design with a bi-amp or fully passive crossover.

I'm sure there would be a lot of folks coming out of the woodwork to buy them up!

Ron