Transmission line speaker build

[oceanobsession]

Well I thought if I could build the cabinets great, if not ive only lost a few quid, my progress

based on the Jensen illuminator but with valve friendly seas drivers seas er kit

http://www.troelsgravesen.dk/Diy_Loudspeaker_Projects.htm

[walpurgis]

Looks interesting. 1/4 wavelength jobbie with a line length of around 5 feet at a guess? I like transmission lines and have built a few in the past. What drivers will you be installing?

[oceanobsession]

Looks interesting. 1/4 wavelength jobbie with a line length of around 5 feet at a guess? I like transmission lines and have built a few in the past. What drivers will you be installing?

CA26RFX alsoT25CF001 and W18NX001, all made by seas

[Reffc]

Neat looking cabinet build. What sort of crossover will you be using, 2nd order series connected?

[oceanobsession]

This is the crossover.

[stupinder]

Well I thought if I could build the cabinets great, if not ive only lost a few quid, my progress

based on the Jensen illuminator but with valve friendly seas drivers seas er kit

http://www.troelsgravesen.dk/Diy_Loudspeaker_Projects.htm
I spotted this earlier, had a quick look at the link but then didn't have time to respond. Looks like a fab project and will be interested to see the outcome. Once again i'm gobsmacked by the skills some folk have to even contemplate this kind of thing....

[Reffc]

This is the crossover.

Can't quite read all the values (old eyes!) but looks like a 2nd order 3 way...perhaps worth checking combined parallel impedance at the crossover points to calculate minimum system impedance? That should give pointers as to how easy/difficult a load they may be. Also, the inductors in the diagrammatic x-over representation look as though they'll be closely spaced and on the same axis...bad idea. If you can maintain around 6 inches minimum between them have have their axis at right angles, this would be a better arrangement for them. I appreciate it's just a diagrammatic arrangement though.

Also, if using different drivers to the ones in the link, you will need to check each of their sensitivities and internal (DC) resistances to ensure that you achieve the correct SPL balance between them which may entail some tweaks to the L-pad resistor values. Their Fas resonance points and range would also need checking to ensure that the same crossover points can be maintained (inductor and cap values).
Apologies in advance if it's a case of granny and eggs.;)

[oceanobsession]

A few more pics

[oceanobsession]

To be honest I know very little about the measerments the designer has taken all that into consideration, he uses various drivers depending on your amplification, I take your point about the inductors, my mate also mentioned this, the mid woofer is placed 19mm in front of the tweeter and also has a shape that must be adhered to, Troels Gravesen is the designer

[oceanobsession]

A few more pics ive build and glued the carcases togeather and now im routing the front panels out which is
harder than you think, ive now ordered all the drivers, and crossovers.

[oceanobsession]

Sorry a few of these are out of focus.

[Spur07]

top notch work Phil

[Reffc]

Yes, very nice indeed :clapclapclap:

[stupinder]

Look great !!!

[Lee Henley]

Looking good mate, nice work

[oceanobsession]

Cheers lee, both carcases now finished, im now on the front panels, lots of work with the router, my eyes are showing the signs of age, which don't help with measerments, hopefully I can cut the holes within a 1mm tolerance, if not a good coat of primer will have to do, ive still got to pick a colour for the front panels, something that would go with the walnut.

catch up soon phil.

[Reffc]

How did you form the driver openings Phil...did you make some templates for the router bush guides?

[Z-A]

Excellent effort, well done..

[oceanobsession]

Hi there reffc, I bought an old elu router 20 years ago for £20 used it a few times for kitchen worktops, you can use it with a 13mm bar and thumb screw lock nut, ill post a few more pics they should explain, I had to make brackets for the smaller holes, all done from a 8mm bolt going throuth my bench worktop, cheers phil.

[oceanobsession]

A few more pics of the front panels, the mid woofer has to be 19mm in front of the tweeter, and also has a 330 degree radius and 45degree shamfer also the tops shamfered, and the sides are 28 degree, I still don't know how to do these at the moment, I fancy a ford copper bronze colour for the front panels which would go with the walnut.1093910940109411094210943

[oceanobsession]

And more

[oceanobsession]

Front panels now finished and ready for gluing of the top, labour intensive for sure.

[walpurgis]

Good work. I hope all your effort is rewarded with fine results.

(about time I embarked on another project myself)

[oceanobsession]

Thanks , ive still some way to go, the crossovers are designed to go at the bottom , but I would like to place them in the cabinet if poss, also I would like to make some steel threaded rings for the speaker to bolt to goes at the back of the mdf seems better than the t nuts/hurricane nuts that people have trouble with in mdf
as you say theres a big risk with the sound quality, suck it and see, I do rate the seas drivers and a lot of people use them audionote for one, and my present speakers shahinian arcs also have there drivers, im hoping they sound like the tdl monitors I heard recently, which were without dout the best ive heard so far.
cheers phil.

[walpurgis]

I don't know about threaded rings. Myself, I'd weld nuts to steel plates which could be screwed inside and accessed via holes in the back, which could be plugged when not used.

[awkwardbydesign]

I use these quite a lot. Can be fixed front or rear, front if you have bevelled the cut-outs. Available in various thread sizes.
http://www.screwfix.com/p/insert-nut-type-d-m6-pack-of-50/59937
And is this the sort of colour? Frugalhorns.
http://i1134.photobucket.com/albums/m604/awkwardbydesign/17052013815_zps9751dd14.jpg (http://s1134.photobucket.com/user/awkwardbydesign/media/17052013815_zps9751dd14.jpg.html)

[awkwardbydesign]

BTW, what's the approximate cost of drivers and crossover kit? I am thinking of building either these or the Illumina-66 2 way speakers. I have a pair of SEAS 25F-EWX 10" units that might just work with this design. If not, easy to go to the CA 26.

[oceanobsession]

Hi there, I have now found the colour for the front panels kia sportage sand track, The drivers inductors resisters and 2 68uf cross caps also 2 0.68uf cross caps and egg crate for both speakers cost £680 inc vat and pp, I still have to buy 8 caps for the mid woofer obbligato 2 caps for the tweeter jansen silver and 2 caps for the mid woofer jansen silver , total build cost £ 1200 ish

cheers phil.

[awkwardbydesign]

Thanks for that. Still not decided whether this design or the Illumina-66s. Decisions, decisions.

[oceanobsession]

I have just had a look at the illumina- 66s, this is my first speaker build so I cant offer much advice, how large is your room , what amplification do you have, both are a challenge to make, good luck with your choice.

[stupinder]

Sending this to a friend in Aus who is talking about a transmission line build...

[awkwardbydesign]

For a first time build, this is pretty ambitious. Looking good, though. Over the last 40 years I have built 20 or more speakers, from 15" Tannoys to Jordan JX92s in size. The Tannoys I had to sell to fund a house move!
As I am not so hot with computer programs, for design etc, I now want to use someone else's expertise.
One thing I have found is that decoupling the bass cabinets from the upper cabinets, as in the original design, can have a very big influence on the final sound. I hung some HF/MF cabs on cords above the bass cabs, and to my surprise it was the bass that improved the most! This was with a 3 way active system, but my wife wants a simpler system, ie. one she can operate! So it's back to passive.
I have 90w EL34 PP valve, 120w transistor or 12w EL84 PP valve amps to choose from, so speaker sensitivity is optional, and my 5.5 x 4.5m room is heavily treated, so it sounds bigger.
I would love to hear yours when they are finished (hurry up!), but Plymouth is a long way away. From everywhere!

[oceanobsession]

Plenty of choice with amplification, ive done plenty of diving and sea fishing from Plymouth, all the drivers turned up today, and im happywith my routings only the bass is to tight, so ive got to take a wee bit more out. im in a little bit of a dilemma regarding the capacitors for the mid woofer as there all high pass they need to be good but the Jantsen supiorcap is £60 ish for a 22uf and I need 8 so there out, obbligato are cheap £16 for 22uf
but they don't make a 5.6 uf so that puts me off, audyn plus do make all the sizes for the mid woofer and £28 for the 22uf, good reviews. sonicaps
have a good rating and seem cheapish. choices choices.

[Z-A]

You have likely seen this test but if not it's worth a read, and may help your choices..
http://www.humblehomemadehifi.com/Cap.html

Regards,
Paul.

[awkwardbydesign]

You have likely seen this test but if not it's worth a read, and may help your choices..
http://www.humblehomemadehifi.com/Cap.html

Regards,
Paul.
I certainly have. Very useful, except when I wanted some MKP1837s in a higher voltage!

[awkwardbydesign]

I've just emailed Troels to ask his advice on which design to choose, based on my room size and listening habits. It will be interesting to see his reply. Assuming he does. If it's relevant I'll post it here.

[awkwardbydesign]

Plenty of choice with amplification, ive done plenty of diving and sea fishing from Plymouth, all the drivers turned up today, and im happywith my routings only the bass is to tight, so ive got to take a wee bit more out. im in a little bit of a dilemma regarding the capacitors for the mid woofer as there all high pass they need to be good but the Jantsen supiorcap is £60 ish for a 22uf and I need 8 so there out, obbligato are cheap £16 for 22uf
but they don't make a 5.6 uf so that puts me off, audyn plus do make all the sizes for the mid woofer and £28 for the 22uf, good reviews. sonicaps
have a good rating and seem cheapish. choices choices.
I have several large Russian MBGO caps which I intend to try, bypassed with Russian Teflons.

[YNWaN]

Richard, you realise that you can achieve the value you want by parallelling capacitors together - this is commonly done.

Also, I don't know if you know but Troels has an arrangement with Jantzen.

[awkwardbydesign]

Lol! Yes, I did know both of those. As for caps, if I want 88-99uF then it's definitely parallel time. And for those who didn't realise it, you can halve the capacitance and double the voltage by seriesing. I don't think that's a word, BTW.
I have capacitance and inductance on my meter, so I check values too.

[awkwardbydesign]

Spoke to Troels by email. He advised the Jenzen CA for my room and listening habits. Fortunately I have a pair of 10" SEAS bass units which he thinks may well substitute for his choice. £220 saved already! And I have sockets, egg-crate acoustic foam, cabling, etc. so more savings. I am about to price up the crossover parts I need and see if they would be cheaper from Audio Components UK than from Jantzen. Scary how much some of them cost!
I will almost certainly mount the crossover externally and isolate it from vibrations; easier to reach too, if need be.
Won't be able to start building until next year, as I am having an operation on 23rd December to repair some crash damage. Bloody bikes! Then 6 weeks in plaster.
Merry Christmas, as Troels said. Cheeky beggar.
So hopefully yours will be ready long before mine, Phil.

[oceanobsession]

Good luck with the build,

[awkwardbydesign]

Just ordering tweeters, mids, felt and all the crossover components from Audio Components; £615! :eek:

[alan47]

These are my trannys.11070.Had them for years,but would love to hear yours.

[walpurgis]

These are my trannys.11070.Had them for years,but would love to hear yours.

Nice. Very similar to a couple of pairs I built in the past.

[oceanobsession]

They look like ipl acoustic, down ilfracome way I think , very nice , working out exactly what your going to do right from the start is the way to go, unlike myself working things out on the way, I wanted to put some sort of cover in the bottom vent hole, it looks like you can use open cell foam, so ive
routed the back hole larger than the front, I was going to use four screws and a large rubber o ring to keep the foam pushed up to the recess, this way you can
replace it when the front covers are glued into place, crossovers and speaker connection plug in panel all must be reachable from the drivers holes, now
painted the front panel in ford Cortina brown to dark I think but it will have to do. the rings are for the bass and mid to screw to they fit in the rear of the front panel . 110801108111082

[awkwardbydesign]

Ooh, progress! I like the veneer, and I guess the photos don't do justice to the front paint. I'm not sure how to do mine, but I want to have a (removable) grill of some kind.
I don't understand the details of this bit- "routed the back hole larger than the front, I was going to use four screws and a large rubber o ring to keep the foam pushed up to the recess, this way you can replace it when the front covers are glued into place" but I'm sure it will become clear later!
I intend to put a removable panel in the base of mine to adjust line stuffing; I've found that useful in the past. I spoke to Troels again about some changes I might make, and he feels any change to damping materials (I have loads of long haired wool) means the TL may not work as designed. But he has also said the damping needed changing from the original amounts. TLs are room sensitve, so I feel the ability to alter damping is vital. I spent months on my first pair!
I am waiting for my bits to arrive from Audio Components (I've ordered everything except the bass drivers), and I hope to make them before 23rd December, when I am having an op on my thumb, Otherwise it could be 3 months after.

[oceanobsession]

Thanks for the advice, you have made me think about the transmission line stuffing, im hoping that if the bass compartment needs more/less wool I can access this by removing the bass speaker, and im going to make the rear top panel a screw fixing as this does not do bass as sutch this should be fine. the open cell foam that I was talking about was for the front vent hole at the bottom 75x200mm, ive ordered some 10mm it looks better than just an open hole exposing the
felt . see http://www.aos-lautsprecher.de/deutsch/lautsprecher/classic/classic.html

These are done the same.

[walpurgis]

the open cell foam that I was talking about was for the front vent hole at the bottom 75x200mm, ive ordered some 10mm it looks better than just an open hole exposing the felt.

Definitely a good idea. Spiders seem to like living in speakers!

For damping the length of the line I used teased, long fibre wool. Works very well. Side walls need thick felt underlay or foam.

[Reffc]

Ooh, progress! I like the veneer, and I guess the photos don't do justice to the front paint. I'm not sure how to do mine, but I want to have a (removable) grill of some kind.
I don't understand the details of this bit- "routed the back hole larger than the front, I was going to use four screws and a large rubber o ring to keep the foam pushed up to the recess, this way you can replace it when the front covers are glued into place" but I'm sure it will become clear later!
I intend to put a removable panel in the base of mine to adjust line stuffing; I've found that useful in the past. I spoke to Troels again about some changes I might make, and he feels any change to damping materials (I have loads of long haired wool) means the TL may not work as designed. But he has also said the damping needed changing from the original amounts. TLs are room sensitve, so I feel the ability to alter damping is vital. I spent months on my first pair!
I am waiting for my bits to arrive from Audio Components (I've ordered everything except the bass drivers), and I hope to make them before 23rd December, when I am having an op on my thumb, Otherwise it could be 3 months after.

Have been trying to access the website for Audiocomponentsuk recently for some inductors but keep getting a Trojan Horse warning message plus website down message...does anyone know if it's been hacked or something? Sorry for thread drift.

Great progress by the way Phil and a good looking finish to the veneers. As Geoff suggests, long lambswool teased out is excellent for the internal damping but can easily be overdone. A little at a time and listen to the results would be a good way to go about this if you can get to the whole line from the woofer hole and base. (personally, I'd go with a removable base section to help...rebate the base in and secure with wood screws or bushed inserts and M4 bolts).

[walpurgis]

By the way, the trade name for open cell speaker grille foam is 'Declon'.

A possibly cheaper source is industrial filters which are the same material and often available in pretty large sheet form, plenty on eBay usually.

[awkwardbydesign]

Have been trying to access the website for Audiocomponentsuk recently for some inductors but keep getting a Trojan Horse warning message plus website down message...does anyone know if it's been hacked or something? Sorry for thread drift.

Great progress by the way Phil and a good looking finish to the veneers. As Geoff suggests, long lambswool teased out is excellent for the internal damping but can easily be overdone. A little at a time and listen to the results would be a good way to go about this if you can get to the whole line from the woofer hole and base. (personally, I'd go with a removable base section to help...rebate the base in and secure with wood screws or bushed inserts and M4 bolts).
Yeah, the website varies from day to day. At the moment the links I bookmarked no longer work. If you google the components you want and follow the link to Audio Components, that sometimes does the job. Apparently their web techs are fiddling with the site, I'll ring them again and try to find out. I did all my ordering by phone, John Bryant is the man you want, and he matched Europe Audio's prices.
A removable panel in the base is the only realistic way to reach the middle section, IME, and that might be where you need to alter damping. In theory, 1/3rd and 2/3rd distance are the most important points, but in practice....?
Update; my links work again, and also link to components!
Originally I googled the speakers I wanted, for example SEAS CA26RFX (H1305-08), and followed that to their site. Then went to inductors. That's working again.

[oceanobsession]

Looking at the plans for dampening the bass compartment with wool is only below behind and over the top of the bass and down the back it doesent go around the transmission line bit if you know what I mean, so im hoping to fix the lower back panel into place with glue.

[awkwardbydesign]

Looking at the plans for dampening the bass compartment with wool is only below behind and over the top of the bass and down the back it doesent go around the transmission line bit if you know what I mean, so im hoping to fix the lower back panel into place with glue.
I emailed Troels about the line damping, and he said using different materials (I have a lot of long haired wool left over from previous builds) could affect the bass performance negatively. A fair point, but polyester wadding varies considerably, and BAF (Bonded Acetate Fibre) is normally specified anyway. Besides, he had to modify the damping himself to get it working properly IN HIS ROOM, so I don't intend to leave myself with no options. My room, and yours, are different, so make the extra effort. That's my advice anyway, based on my own experience. After all, if it works perfectly first time, you don't have to use the hatch. It would be a pity to find you can't fix a problem, and it is quite common.
Even the "egg-crate" foam comes in varying densities, and that will affect it too.
Having said all that, it should be fine, if I didn't trust his design abilities I wouldn't be building them myself!
Been looking at veneer today. Decisions, decisions!

[walpurgis]

Loose synthetic fibres and bonded synthetic fibres are not a patch on wool for damping and dispersing energy at lower frequencies. Wool fibres have a microscopically rough surface causing the fibres to abrade against each other and work off energy.

[oceanobsession]

Thanks folks for all your help and advice, I take your point regarding the differences in dampening material, egg crate etc , i was going to use Baltic birch but in the end decided to go with mdf, you can also use reel wood veneer ply but with voids, pity you cant get Baltic birch with reel wood veneers best of both, or you
could spray them all over in 2k car paint, Baltic birch screws togeather better than mdf so maybe better for removable hatches, i never fancied mitering the corners you have to be spot on and there also weak, i can recommend the clark bj 600 biscuit joiner £59 from machine mart, very good for the money. i still cant
make up my mind with the caps for the mid and tweeter, clarity cap esa for the mid maybe and mr for the tweeter.decisions decisions

[oceanobsession]

Hi there, I bought monacor mdm-3 sheeps wool and polyester mix 35mm and monacor mdm-40 egg crate, im getting a bit worried about this bit but his plans tell you how to place everything. thanks for the info

[awkwardbydesign]

Why not Jantzen caps? Get the best cap you can afford for the tweeter. And I'm not mitreing either, I think it's only so Troels could use the birch ply without veneering. I will biscuit, glue AND screw my outer carcass as I will be veneering later. I also intend to put angled corners in the line although Troels said it measures and sounds the same either way. Maybe that's true, but it will brace the panels more at the very least, and I will sand fill the voids to deaden it further; I HATE the sound of cabinets, which is why I have a weakness for electrostatics, but they have their own issues.
I'm sure yours will work really well anyway, it's just that I am a bit obsessive about certain things, as I can hear those things. My ears and brain work one way, others have different priorities.
Hopefully we can both be finished before Christmas, I have to or else wait another 3 months. The race is on!

[awkwardbydesign]

While sat here waiting for the courier (guaranteed to stop him coming today!), I've been looking at the Jenzen designs with other drivers, and the Accuton version mounts the tweeter panel separately on Sorbothane pads. I'm considering doing it that way with the SEAS tweeters, particularly as I intend to suspend the top cabinets completely free of the bass cabinets. And chamfering the edges more. http://www.troelsgravesen.dk/Jenzen-D.htm#CABINET
If I modify my cutting list now it won't be hard to do, and changing tweeters in the future would be easier too. Pity I can't afford the better drivers!

[awkwardbydesign]

Have been trying to access the website for Audiocomponentsuk recently for some inductors but keep getting a Trojan Horse warning message plus website down message...does anyone know if it's been hacked or something?
I spoke to John Bryant today, and he says the site was hacked a while ago. There is no personal or financial info. on the site, so the hackers got nothing useful. They tried to work around it with no success, so a new website is under construction, and should be up in a week or so. If you go here- http://www.audio-components.co.uk/ you should be able to get in to the current site. Then phone them for ordering etc.

[awkwardbydesign]

Hi Phil, are they finished? You haven't posted here for while, so I don't know.
Mine are up and running! Not veneered or anything, but I am listening to them now, and they sound pretty good. Made a few minor alterations to Troel's plans, but kept to crossover design and components. I will be posting a thread over on the WigWam in DIY, so you can have look there if you want.
I got them running at midnight, as I had an operation booked for this morning on my thumb. Six weeks in plaster now, so last night was the deadline. It was pretty intense trying to get them done, but I made it. And typing with my left hand is not easy!

[oceanobsession]

Hi there, its great to hear that you have made a success of your project, I wish I could say the same but mine are now in the local tip, I haven't give up, but some
of the mistakes made early on in the build I could not recover from, basically I was never happy with the front panel flush fit so I made the mistake of putting buiscuits to close to the edge and on gluing they swelled out which split the side. my next attempt will be in Baltic birch separate boxes as the pattern but with
back and front rebated, It will be interesting to see how you have made your speakers , maybe I can nick a few ideas. im sure they will sound better as things
loosen up a bit, anyway get well soon phil.

[awkwardbydesign]

I was really gutted to hear about that. I went for 18mm birch plus 6mm MDF to get the thickness, glued with cheap PVA. Used the good stuff for construction though! Do yourself a big favour and put hatches in the base for restuffing. Seriously. Although Troels may have got it right in his room, we aren't there! I am definitely going to change the bass drivers, as mine don't have the control needed for the TL design. Bigger magnets for higher QES and lower QMS suspension. More control for the cone from the amp.
I will also reshape the tweeter panel like the diamond Jenzens, and fit it the same way. Ordered a 60 degree router cutter to bevel the edge of the bass cabinets too, a bit like the Jenzen Illuminator cabs.
On my previous 3 way active speakers, I suspended the MF/HF cabs above the bass cabs with no contact at all between them. To my surprise it was the bass that cleaned up the most! I was expecting it to affect the midrange more, but no, it cleaned the bass. Go figure, as they say.
Also I think I will stick the Seismic Sink platforms under them and see what they do for these speakers. At the moment they are sat on felt pads so I can slide them around on the solid oak floor.
Let me know if there is anything I can do to help, us Jenzen builders should stick together. :)
Just escaped from the daughter's after Christmas lunch. Pleaded injury!

[oceanobsession]

Hi there again don't know your name, yes I think putting the ca26rfx bass drivers in place may correct some of your problems, theres a guy on ebay that will cut
Baltic birch to within 0.2mm and can guarantee no voids that's all they do, there in Nottingham I sent him this list to see what the price was like,


Dear farmwoodproducts,

750x407x4 off
407x274x4 off
750x324x4 off
800x457x4 off
457x324x4 off
800x374x2 off

Baltic birch 18mm I would collect from Nottingham cheers phil.

£132 inc vat

[oceanobsession]

Im not keen on the flush fitting front panel of the bass cab,I would like to add 25mm to the depth and fit a 50mm front panel half inside half outside this is possible to do, but when you come to the mid cab you get problems, either way even if its only 5mm im having the front panel fit inside slightly, I need to buy some f cramps for gluing, ive got some scrap steel batteries etc im hoping will pay for the birch ply, the whole thing has to be right in my head before I start work
this time, another idea I was considering was to use 10mm steel rod 2mm short of the depth with 6mm thread in each end, use 6 for the bass cab pulling the back and front to the box 25x25 glued wood in the corners as stops, I wood rather glue all panels than use screws but I take your point about your room etc,
have you ordered the bass drivers.

[awkwardbydesign]

I haven't ordered yet; it's Boxing Day. I screw AND glue, it seems to work, but the fronts are only glued for now until I finalise everything. As for cutting, I am happy to do my own, as I can easily shave a mm or less off if I need to. The veneering will be done last, so I can smooth and fill the cabs before then. The tweeter panel will change shape before then anyway.
The speaker position is pretty much set, so I can't move them for best bass; restuffing will be my only option. If you look at designs like the PRO-9TL, it gives some helpful hints. I made a pair of them many years ago, and the bass was pretty tight, as I recall. http://p10hifi.net/planet10/TLS/downloads/Pro9TL-Mk2.pdf
Dick.

[oceanobsession]

Well folks after my first attempt at making speakers went pair shaped, ive had another go this time using Baltic birch, ive finished the mid cabs and
just need to glue up the bass cabs, then ive the crossovers to do , I have spent lots of hours on these, and cant wait to hear them, ive posted a few pics . phil.

[oceanobsession]

And a few more.

[Reffc]

Nicely done Phil.

[awkwardbydesign]

Looking good. Not sure about your midrange stands though! :)
I'm still fiddling around with mine, just started veneering the curved side panels. I always seem to make life hard for myself!
But I've discovered they are sensitive to cabling, so I intend to rewire with some homemade Litz wire, and as few connections as possible; straight from the crossover box to the drivers.
I've also changed the midrange drivers to the Nextel version, so have a pair of the ER18RNX drivers spare if anyone else wants to start a build!

[oceanobsession]

Well I have now finished the speakers apart from painting them which I will do another time in the future, only the crossovers to build now, and which capacitors to choose for the mid and tweeter. I was going to paint them in a citroen gun metal metallic which ive seen on a c3, I think it will look nice with the black drivers, also I may have to play with the stuffing in the line , a few more pics cheers phil.

[awkwardbydesign]

Looks like you might be finished before me after all! It would be interesting to get them both together one day, but that could be tricky: they're big buggers. Transmission line surround sound!:lol:
I am having problems with the veneering of the add-on sand filled side cheeks. Taking more time than I thought, and I've had to run the grain vertically instead of horizontally. I just hope the black leather fronts are easier!
http://i1134.photobucket.com/albums/m604/awkwardbydesign/JENZEN%20SEAS%20ER/20140511_115849_zpspq8aeq4a.jpg

[oceanobsession]

Hi dick, looks nice the side cheeks, how does the new mid sound, im now looking at putting the crossovers in a box , mind blowing trying to understand it all, cheers phil.

[awkwardbydesign]

The NEXT mid has more detail, but sounds a little forward. And I still have sibilance issues, so I emailed Troels with a couple of questions. The NEXT crossover has a couple of LCR circuits across the tweeter, to reduce sibilance and boost HF above 10kHz, so I will try adding those to the existing crossover. And the mid level can be reduced by changing the two 5.6 ohm resistors for two 6.8 ohm, for example. And the NEXT circuit doesn't have the resistors in series with the inductor C2051, which should steepen the cut off.
I'll try these changes and see how they go. I'll report back when I do. Also going to make a bigger crossover box to allow for changes, and hang it on rubber vacuum cleaner drive belts on the back of the bass cabinet; ugly, but won't show from the front.
It's all taking more time and effort than I wanted, this was supposed to be easier than the active system I had before. :doh:

[YNWaN]

Looks like you might be finished before me after all! It would be interesting to get them both together one day, but that could be tricky: they're big buggers. Transmission line surround sound!:lol:
I am having problems with the veneering of the add-on sand filled side cheeks. Taking more time than I thought, and I've had to run the grain vertically instead of horizontally. I just hope the black leather fronts are easier!
http://i1134.photobucket.com/albums/m604/awkwardbydesign/JENZEN%20SEAS%20ER/20140511_115849_zpspq8aeq4a.jpg

Hi, yes, you would have to run the veneer vertically (but you know that now :)). The best way I have found to veneer curved surfaces (or to create curved laminates which is more often what I do) is to use a vac-bag. Not much help I'm afraid as you need an air pump etc. - does work well though.

Nice work by the way :).

[oceanobsession]

You must have good hearing, im doing the same putting the crossovers at the back of the bass cabinet, 300x300 type size

[awkwardbydesign]

Hi, yes, you would have to run the veneer vertically (but you know that now :)).
It's quite feasible to bend across the grain, http://www.troelsgravesen.dk/Jenzen-Accu-Bjorn.htm but my veneer is raw (not paper backed) and dry, being quite old. Too much work for me in the end, though! My test pieces demonstrated the problems (and solutions), but I decided life was too short! The crossover and front panel profiling is more important, and I had started to lose the will to live. Besides, the weather is improving and I want to get the bike out.
http://www.troelsgravesen.dk/Jenzen-Accu-Bjorn/jenzen-accu-bjorn-11.jpg
http://www.troelsgravesen.dk/Jenzen-Accu-Bjorn/jenzen-accu-bjorn-13.jpg
http://www.troelsgravesen.dk/Jenzen-Accu-Bjorn/jenzen-accu-bjorn-14.jpg

[YNWaN]

I've not tried that, but if you soak it etc. It does seem like a lot of work to try to get the veneer to do something it doesn't want to though.

[awkwardbydesign]

You must have good hearing, im doing the same putting the crossovers at the back of the bass cabinet, 300x300 type size
Make sure the box is big enough for future mods. I had 340 x 230, and it's not big enough now; I'm going for 400 x 250, with the bass wiring going in near the top of the back panel, and the mid/tweeter wires straight up the outside of the back panel until they enter the top cab. The 2 binding posts on the crossover box will be on the top edge along with a pot for tweeter level. http://cpc.farnell.com/1/1/93478-switch-3pole-4-pos-ck1026-lorlin.html I will parallel all 3 poles to get enough current handling. And the box lid will be quick release so I can get at it all quickly; I feel that may be happening a bit!

[awkwardbydesign]

I've not tried that, but if you soak it etc. It does seem like a lot of work to try to get the veneer to do something it doesn't want to though.
My feelings exactly, but it is a way of mimicking solid wood. It would be worth it with small speakers, but too time consuming with the Jenzens.
http://www.hi-end.lv/1136-large_default/sonus-faber-oplympica-i.jpg

[oceanobsession]

Crossovers now built, still a little bit to do but ive had a listen today.