Fostex horn - repair, refurb, repurpose! [Archive]

michaelg

02-07-2018, 04:59 PM

hjames started this new thread on fixing up the Fostex horns she just won on eBay.

The thread below starts from post 128 in the old "Mystery Large Format Monitor" -

http://www.audioheritage.org/vbullet...ormat-Monitors (http://www.audioheritage.org/vbulletin/showthread.php?5229-Mystery-Large-Format-Monitors)

Howards orange oilI have no idea what "Howards Orange Oil" is but the horns are TEAK and you should use TEAK OIL! Real teak oil, not the junk that dries like a paste or a varnish.

The wood has to "breathe". I can provide you with some guidance in that area if you have problems locating the good stuff.

Michael.

hjames

02-07-2018, 07:23 PM

I have no idea what "Howards Orange Oil" is but the horns are TEAK and you should use TEAK OIL! Real teak oil, not the junk that dries like a paste or a varnish.

The wood has to "breathe". I can provide you with some guidance in that area if you have problems locating the good stuff.

Michael.No, no, I understand.
The orange oil is safe for walnut and other woods and does not contain wax or clog the pores like that sticky Tung oil or the Watco Danish oil ...
I had JohnW make a beautiful pair of walnut horns for me a few years back -
they were gogeous smith horns in walnut, and seeing how these teak horns were treated is very sad.
I am basically going to wait before I do anything to restore the horns and fix the crack.

I have an early morning - I'll talk to you later!
And thank you for making contact!

gdmoore28

02-08-2018, 05:41 PM

Lee in Montreal

02-08-2018, 06:19 PM

35 years later, I still love everything about these speakers. ;-)

Thanks Michael for your work.

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=6122&stc=1&d=1111622950

hjames

02-08-2018, 06:46 PM

Heather, you are into projects constantly, aren't you? I love watching them.

I know there's an urge to clean them up and make them look nice, but I would not do any more to them until you have them repaired. Any residue of cleaning or restorative chemicals that happen to seep down into those cracks is going to make it unlikely that the resins that will be used to repair them will stick. That would be bad ju-ju.

GeeDeeEmm
Understood, thanks.
I'm only heavy-oiling the one without the cracks.
The split lip will def need to be dry for glue to work.
I'll clean off the tape reside but not much else on that one.
You can see after work today I got a lot of the tape residue cleaned off of the uncracked one on the left -

And yes, its a pretty wooden piece - its TEAK - how could I resist?

The metal adapters have a 4 bolt pattern, and what seems like a 3 bolt pattern for 1 inch JBL drivers.

80054

80053

I did not even notice until now - note the Delos CD in the black box just above the right horn.
Won it in a contest here on the Lansing Hermitage Forum, back in 2007! Thanks again, King James & TiDome.

hjames

02-10-2018, 09:26 AM

BTW - kind of thinking of chasing down a pair of 2420 horn drivers for these - so they would be JBL based.

Had a chance today to gently take out the screws and examine the broken horn better. I believe they were originally machined and glued together -
then someone dropped one of them and slapped it into place with duct tape and sheet-rock screws!!!
Anyway, I have not oiled it, just taken it apart to look. The clamp is just holding 3 pieces together to see how they fit.
Its teak, so its a pretty dense wood.

I'm thinking very minimal use of Gorilla Glue might be the best way to glue the broken pieces back together.
In stages. Glue the plank pieces together for the 2 back sides of the horn.
Glue the 2 parts of the top lip back together.
Clamp well to prevent expansion/distortion of the original shape.
Then after all that has had a day to set up and dry,
Glue the top lip back onto the lower assembly.

Some of you folks are much better with wood than I am -
does that sound like a reasonable approach?

(Its got to be better than duct tape and sheet rock screws, right?)

8006580066

Earl K

02-10-2018, 09:47 AM

Nice pics Heather ( they certainly offer a nice over-view on this horn type ),

My inclination ( after seeing how many broken pieces you have ) would be to completely replace the "slab-like" side-walls with new, solid walnut pieces ( while saving & repairing the teak horn bells ).
- Of course this is easy for me to say from a long-distance perspective.

You might want to reach out to some of our talented wood-workers here at LHF for some more repair opinions ( maybe even start a new thread ?? ).

:)

Lee in Montreal

02-10-2018, 10:03 AM

Thanks for sharing the pictures. If it were me, I would look for a fresh slab of teak and replace the broken parts instead of just glueing them back. I understand that teak might be expensive on this side of the Pacific, but in Asia, it is extremely common and cheap. Back in the early 1970s, my parents were importing stuff from Vietnam and it was crated in teak 4'x4' boxes which were disgarded once the content was unpacked. Teak is dense, hard and doesn't rot as easy as common wood. Great fro making crates. And horns. ;-)

hjames

02-10-2018, 10:58 AM

Yep - it DOES make sense to make a new thread for this and not squat on the older "Mystery Large Format Monitors" thread.
(http://www.audioheritage.org/vbulletin/showthread.php?5229-Mystery-Large-Format-Monitors)

Anyway, I found a pair of wooden horns on the auction site. They reminded me of the gorgeous walnut horns JohnW made for me a few years back for my L200 project.
But the auction horns looked abused. faded like they'd been let out in the weather. One had an obvious crack and someone had run Sheet rock screws in to hold it together.
Duct tape residue across the lips of both of them. Butcher work!
But the price wasn't too bad, I thought I could improve them, and after the sale the seller offered the original metal adapters with them - for 1 inch drivers.

Anyway - they arrived mid week and I wiped down the horns with "Oops" to get rid of the tape residue, and wiped down the intact horn with Howards Orange oil to see if that would refresh the wood ...

Update - Michael Gillespie from Fostex wrote in the other thread and said the horns are made of TEAK! I'll get some Teak oil today
8007680077
8007880080

80079

hjames

02-10-2018, 10:59 AM

Done - it DOES make sense to do a new thread on these Fostex horns I'm fixing rather than "squat" on the older discussion here.

http://www.audioheritage.org/vbulletin/showthread.php?40573-Fostex-horn-repair-refurb-repurpose!

Thanks for sharing the pictures. If it were me, I would look for a fresh slab of teak and replace the broken parts instead of just glueing them back. I understand that teak might be expensive on this side of the Pacific, but in Asia, it is extremely common and cheap. Back in the early 1970s, my parents were importing stuff from Vietnam and it was crated in teak 4'x4' boxes which were disgarded once the content was unpacked. Teak is dense, hard and doesn't rot as easy as common wood. Great fro making crates. And horns. ;-)

macaroonie

02-10-2018, 11:00 AM

[QUOTE=hjames;412696]BTW - kind of thinking of chasing down a pair of 2420 horn drivers for these - so they would be JBL based.

Had a chance today to gently take out the screws and examine the broken horn better. I believe they were originally machined and glued together -
then someone dropped one of them and slapped it into place with duct tape and sheet-rock screws!!!
Anyway, I have not oiled it, just taken it apart to look. The clamp is just holding 3 pieces together to see how they fit.
Its teak, so its a pretty dense wood.

I'm thinking very minimal use of Gorilla Glue might be the best way to glue the broken pieces back together.
In stages. Glue the plank pieces together for the 2 back sides of the horn.
Glue the 2 parts of the top lip back together.
Clamp well to prevent expansion/distortion of the original shape.
Then after all that has had a day to set up and dry,
Glue the top lip back onto the lower assembly.

Some of you folks are much better with wood than I am -
does that sound like a reasonable approach?

(Its got to be better than duct tape and sheet rock screws, right?)

You called ? Always happy to help a Lady in distress . See next post. M

hjames

02-10-2018, 11:17 AM

Anyway - they arrived mid week and I wiped down the horns with "Oops" to get rid of the tape residue, and wiped down the intact horn with Howards Orange oil to see if that would refresh the wood ...
BTW - kind of thinking of chasing down a pair of 2420 horn drivers for these - so they would be JBL based.

So - its the weekend. Today, Saturday, I had a chance to gently take out the screws and examine the broken horn better.
I believe they were originally machined and glued together - then someone dropped one of them and slapped it into place with duct tape and sheet-rock screws!!!
Anyway, I have not oiled it, just taken it apart to look. The clamp is just holding 3 pieces together to see how they fit.
Its teak, so its a pretty dense wood.

I'm thinking very minimal use of Gorilla Glue might be the best way to glue the broken pieces back together.
In stages. Glue the plank pieces together for the 2 back sides of the horn.
Glue the 2 parts of the top lip back together.
Clamp well to prevent expansion/distortion of the original shape.
Then after all that has had a day to set up and dry,
Glue the top lip back onto the lower assembly.

Some of you folks are much better with wood than I am -
does that sound like a reasonable approach?

(Its got to be better than duct tape and sheet rock screws, right?)
Picture of the Fostex adapter next to a JBL 2327 adapter -
- the 3-hole pattern is the same as the 1 inch JBL drivers!
- and the 4 hole pattern lines up with the Altec 2 hole pattern!

8008380084

Earl K

02-10-2018, 03:55 PM

Westlake Audio has used a somewhat similarly ( inspired ) horn in some of their monitors .

80093

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=59341&stc=1&d=1372596594
http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=80096&d=1518302982

Although, there are some significant differences when comparing the throat entry areas.

:)

macaroonie

02-10-2018, 04:11 PM

Hi Heather < I thought I'd drop in and lend a hand.

Gorilla is not really suited to this task as it tends to expand slightly. My go to here would be Titebond Original. It has great bonding properties with open wood , is easy to clean up excess and is not unpleasant to work with.

Joining Teak , as it is an oily wood it is a good idea to get any latent oil off the surfaces you are trying to join. Q Tip and acetone or MEK dab all over and discard as needed. Allow time for that to flash off before using Titebond.

Next you have the problem lf creating secure tight joints. In the first instance I would do a dry fit by hand to see if the surfaces mate properly. You may find the odd splinter will stop a good tight fit so these need to be located and removed. If you can post pics of the mating faces I'll have a looky.

80094

I would have a go at pieces 1 and 2 ( above ) test for a dry fit using the flat surface face down on a piece of MDF or ply. Next prob you have is clamping. Because you have curves and angles everywhere it will be tricky to get a good grab on anything, I would look at securing the mouth (1) by using a couple of bits of ply about 12" x 3" reaching towards the driver exit. Outside the periphery of the horn mouth fashion a block support such that the ply plates are sitting nicely on the inside surface. Put a couple of screws in between the block and the lip. This will create a down force hopefully holding the part steady, You could use double stick tape but then you have a battle to release it.

For the throat part (2 ) you will need to affix blocks in such a way that with the part in place you will be able to insert little wedges to create the pressure on (1)

I'll see if I can sketch up a diagram. Better still if you can post a pic of parts 1 and 2 on their flat surfaces with the mating faces about 10mm apart , I'll edit the pic to show you whats needed.

hjames

02-10-2018, 04:55 PM

Okay - I used a small chisel to clean up dried glue from the original assembly process.
I dry fitted the pieces to see how everything fit - it went together brilliantly - no apparent problems
(Other than the slightly spread places where some dummy used sheetrock screws and slightly split the back panels).

So - here are pictures from the 3 gluing processes I did ...

8009880099

I clamped across the back to pull the pieces tightly together, then used small clamps to clamp downward
to hold the small parts against the inside of the curved lower lip.

80100
The front edge of the top lip had been knocked off, which gave me a flat edge to set the clamp against.
It appears these 2 pieces were assembled this way at the factory - the 2 pieces of wood have a different color and grain.
It may not look flat from this photo, but I had a straight edge and it is.

80101
The top is glued down to the top of the back planks and there is a thin glue bead on the back of the upper curved lip.

hjames

02-10-2018, 05:15 PM

Just for comparison, this is the other horn. It was not dropped and was not "broken."
You can see on the first picture where it looks like 2 different pieces (difference in color and grain)
were glued together at the factory.
The black paint is from a nylon block that was on the bottom of the horns.
(I managed to get that black paint off with gentle use of the chisel and a sanding block.)

8010280103

hjames

02-11-2018, 05:11 AM

Got a few gashes on the front lip, but they are basically healed and ready to use!

Ordered a can of Teak oil from Amazon yesterday and I'll try and get the faded places rejuvenated with that.
Home Depot did not have any ...
I also need to get a pair of horn drivers to see how they sound ...

80112

And I confirmed, the Fostex adapters will fit either Altec or JBL 1 inch driver mounting patterns. Very cool!

80113

So, maybe I should plan to build some 2 ways with those Altec Model 15 cabinets I still have,
and the JBL 2214H drivers I still have ... all I need is a pair of 1 inch horn drivers and build a crossover.
I could sure do worse (Note: I no longer own the Altec horn drivers shown)

80114

macaroonie

02-11-2018, 05:36 AM

Result , looks like you got the wood gods on side.

Show me some close ups of the front lip damage , there are some neat tricks for this kind of thing.

You will need some teak offcuts,

hjames

02-11-2018, 07:24 AM

Result , looks like you got the wood gods on side.

Show me some close ups of the front lip damage , there are some neat tricks for this kind of thing.

You will need some teak offcuts,

Okay - top view, front view, bottom view of the bad Lip that has the outer edge knocked off it.

Off to church soon - if you need anything closer or a different angle, let me know!

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rusty jefferson

02-11-2018, 07:30 AM

Heather,

Very nice, another interesting project. I've got a minty pair of 2425h drivers sitting idle I'd like to see go to good use.

There's nothing special in Teak oil. It's something marketed primarily to the marine marketplace because of the prevalent use of Teak on boats/yachts. Use whatever Tung oil products/blends you like.

rusty jefferson

02-11-2018, 07:39 AM

I've also got a few scrap pieces of Teak in the basement you're welcome to for making a "Dutchman" repair on that edge.

macaroonie

02-11-2018, 08:14 AM

80121

Good stuff. If you can get some offcuts from Rusty that would be great.

For the wee ding try this , take a scrap of lighter coloured wood and sand it so that you have a nice pile of dust. mask off other than the general area you are working on.
Multi stage process here , make a little pile of your dust in the ding and tamp it down. Wick some thin CA ( superglue ) into the dust and leave to harden. Do this as many times as it takes to build it up. Sand back to conform to the correct shape.
It will appear a little darker due to the wetting of the CA , thats why I said get some lighter looking dust,

For your front lip you will need to plane that nice and flat. Too big for the CA treatment If you are lucky Rusty will have a piece where the grain has a similar pattern to your damaged lip. Basically make mating surfaces , dont try to shape that patch exactly , near is good , glue up and then conform to shape.

Without a plane a nice flat sanding block will get you there. Stick 60-80 grit in to a piece of MDF. Patience will get you there.

hjames

02-11-2018, 01:33 PM

Very cool Rusty and Mac! Thanks for the assists.
I know I roared through the work yesterday - but I'm alternating between projects,
so it may take me a while to get back to this project!

hjames

02-11-2018, 08:09 PM

And I just won the rest of the seller's kit on eBay - should have them by the end of the month ...

801248012580126

And what the stacks looked like when new ...

Lee in Montreal

02-11-2018, 08:30 PM

Oh that's nice. I can see a complete Fostex clone w/ 15" woofer in the future. ;-)

Mr. Widget

02-11-2018, 11:45 PM

And I just won the rest of the seller's kit on eBay - should have them by the end of the month ...
Awesome! Keep us posted... very exciting.

Widget

macaroonie

02-12-2018, 08:06 AM

Footnote , on the front lip I would be wary of planing unless you have a very sharp plane and can make minimal cuts. You have rising grain at both ends and there will be a high chance of catching or tearing.
Prob best to stick to the sanding method. If you place the lip just protruding over a straight edge of ply or MDF ( clamp it down ) and use a longish block of nice square 2x2 as your sanding tool. This will stay nice and square and if you take nice long strokes you should get a good result. :)

https://www.youtube.com/watch?v=XycqnPGcbvM

From 3.0 on. You are using a dressed 2x2 with abrasive but the principle is the same

Earl K

02-12-2018, 08:25 AM

And I just won the rest of the seller's kit on eBay - should have them by the end of the month ...

801248012580126

And what the stacks looked like when new ...

Very exciting stuff Heather!

:)

bldozier

02-13-2018, 04:16 AM

hjames

02-13-2018, 05:37 AM

i had bid against you, nice win heather. i swore my auto bid was going to win.
apparently NOT. ultimately i was allowed to bid.
they look ok cleant up as well,
an im sure the sound will equal their looks.
Ah, I have not had the best luck with Sniping software - I was logged in at 6:55 PM or whenever that one scheduled to end.
I had figured the maximum I was willing to pay, added 10% to that, and bid directly at 0:30 seconds before it ended.
Then once I won the horns and had done the initial repairs on them by Saturday evening, it sorta made sense to buy the rest of the stack on Sunday for another $xxx (shipped).
Pretty much wiped out my "play" funds - hope I have a Tax refund coming this year!

hjames

02-15-2018, 02:55 PM

The rest of the Fostex parts have arrived. I assembled the stack (sans horns, for now) -
I have some minor fixes left to do on the horns, and I'll need to build a crossover
before I can feed signal to the super-rare drivers.
God, the drivers are SUPER heavy!!

80147

Yes, they are sitting on top of one of the recently new-to-me Heath "Valencias" -
thats another project for another time. I figure I'll pair the Fostex stack on top of
an ALTEC Model 15 Cabinet I have with a JBL 2214H for the woofer.

hjames

02-21-2018, 12:01 PM

Minor updates - I've had a busy week with many OTHER things - tires on Emma car, wee snowstorm, and a birthday too ...
"Will you still need me, will you still feed me ...?"

But I got time to assemble all the parts and mock them up on top of the Altec Model 15 cabinets.

I know how nice the JBL 2214H sounded when I had them in the cabinets with the Altec horns drivers & crossovers in Dec,
and since no one seemed to want the empty cabinets when I tried to give them away after I sold the Model 15 parts,
it seemed like a no-brainer to use cabinets for the woofers ... tho I'll need to cover the hole where the horn mounted,
and make a plate for the old crossover holes to mount the Lpads for the mids and tweeters.

And one of the Fostex guys sent me a crossover schematic to pair the JBL woofer with the Fostex mid and tweeters -
tho I have not ordered parts to build them yet ...
At least the cabs have the Altec velcro dots I can use when I make grills for them (later)

80209

hjames

02-21-2018, 03:00 PM

Dropped by Home Despot after work to see what they had in the way of small piece of plywood to cover the horn-hole.
I saw all kinds of pieces of 2' x 4' plywood from $8 or so for chipboard to well over $20 for pieces with nicely veneer on 1 side.
But I only need 2 pieces of 18" x 8" or so - so their stock was overkill - till I saw a decent piece of ply in a 2' x 2' size - over 3/8 but just under 1/2 thick - is there a 7/16ply?
It had sticker with a bar code, but no idea what it sold for. Decided to buy it anyway. Got up front and the cashier rang it in - $0.01 - thats it!
Perfect for my project and what a great price!

Now I just need to haul my table saw out of the shed, set it up on the shopmate, and make a couple cuts!

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SEAWOLF97

02-22-2018, 07:43 AM

Have no doubt that your horn project will turn out great (as always).

Our HD just puts out the wood scraps in an open front dumpster with a FREE sign, usually a lot to choose from. (and it's close to the side doors)

FOSTEX ?? My only real exposure to that company has been their headphones, which I really enjoy. They seem to be an innovative, quality oriented company.

TEAK ? The woods beauty was what initially drew me to the JBL "Ti" series. Now I have 18Ti's,
120Ti's and the 250Ti's. :)

hjames

02-25-2018, 02:53 PM

Cut planks out of that plywood - painted the ugly side black and put a piece inside the cabinet up against the horn hole.
Decided I did not like the look, so I got some Minwax stain, brushed it on the nicely grain side and tried that in the horn hole - not perfect, but better.
Go some wood adhesive and my caulking gun - ran a bead around the edge of te stained panel, and mounted it inside the cabinet.
Probably needs another coat to better match the pateina of the golden oak finsh Altec used - but it looks nicer than the black did.
Took one of the JBL 2214H woofers and mounted it back in the cabinet - Not bad so far.
Now I need to order parts and assemble the 3-way crossover, and see how it all plays together.

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hjames

02-26-2018, 07:45 PM

I did take some time today, connected the horn and tweeter together so I could test them, and fed some music to them, just to be sure the parts were working.
I know, the seller told me they were working, but before I ordered parts to build the 3 way crossovers for them, I wanted to be sure.
Connected them to the Jolida amp, turned the volume WAY down, and played bits of Joni Mitchell's Hejira - Coyote ...
Brought the volume up a little bit and - they sounded good - nice voicing from the duck lips - and the proper sizzle from the slot tweeters ...
I even connected the JBL 2214H woofers in parallel, just as a test - the combo sounds pretty reasonable -
Time to order parts!

80266

dkalsi

02-27-2018, 08:54 AM

Looks like an interesting build. Are you designing your own crossovers?

hjames

02-27-2018, 10:16 AM

Looks like an interesting build. Are you designing your own crossovers?

I asked one of the Fostex engineers and he designed and sent a crossover schematic that blended the JBL 2214H woofer
in with the FOSTEX Horn Drivers D252 (on the teak horn) and the FOSTEX Super Tweeters T825 ...

I tested the drivers yesterday to confirm they did indeed work (ebay seller said they worked, but, you know how that can be) -
so now I just need to order parts and some perf. board and a week or so later, assemble the bits!

hjames

02-27-2018, 02:58 PM

So, after being nagged by a member in another forum (Why haven't you hooked the Fostex horn up in place of the horn in those Heath speakers?)
and had that thought nagging me overnight, well, after I got home tonight, I went for it!. Pulled the Heaths out and laid them down, pulled 20 screws from the back of each to open the cavity,
marked the black lead on the original horns, pulled the hipass leads from the original crossover, and fed them out under the back cover before closing them up.
Stood them upright, hooked up the Fostex teak "Duck lips" horns with the FOSTEX D252 drivers, and again, turned on the tubes with low volume.
Started through my demo playlist - Joni Mitchell and Hejira again - first Amelia, then Hejira

OMG, these are some sweet horns and drivers!!

(Oh, I had mentioned at one point I emptied a pillow of Polyfill into each cabinet and extened the bass response of the "Valencias" - here's the pic)

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Earl K

03-04-2018, 07:18 PM

RWO/Fostex ( maybe? ) inspired by:

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:)

gibber

03-16-2018, 07:07 PM

RWO/Fostex ( maybe? ) inspired by:

80363

:)

Well, seeing them today, it's hard to believe these are mid '70s. But, there's nothing as strong as an idea whose time has come (thus (https://en.wikiversity.org/wiki/Talk:Victor_Hugo_quote) quoz (https://en.wikiversity.org/wiki/Talk:Victor_Hugo_quote)*they*, not Hugo (https://en.wikiversity.org/wiki/Talk:Victor_Hugo_quote))

From my re-collection, the Matsushita units, designed helping to launch the "Technics" brand were themselves strongly informed by the series Richard Heyser had started to publish in the AES journal year '73 onwards. Same happened on the amplifier front where the Japanese brands came up lightning-fast with fantastic designs strongly influenced by Matti Ottala's late '70s work on speed-limited mechanisms of distortion.
The Kenwood KA amps and KT series tuners, the Pioneer "SA" amps and "Exclusive" speakers, Yamaha CT-7000 and NS-1000, were other examples of this extreme dedication to follow up on latest research in materials and topologies. So Fostex, founded in 1973, was in good company and the quality of the Japanese work of the 1972-1982 period is still getting more and more appreciated after all these years... so many classics, such a small basement :banghead:

The US brands DCS and Dahlquist picked up on the time-of-arrival topic in multi-way speakers pretty early as well. In Europe, Dynaudio, B&W and later KEF did the same -- Ralph

Kreativlos

01-05-2019, 08:57 AM

Lee in Montreal

01-05-2019, 10:55 AM

The user Earl K mentioned that someone here might be able to help me out so I will repeat my question here, thanks in advance!

can anyone provide Crossover schematics for one of the monitor models? I just bought a near NOS pair of T825 and FD600 and would like to try the original crossovers from the monitors.:)

best regards from germany

Hi there.

Perhaps being specific about which one of the Fostex LS serie monitor models could help increase the chances to get a reply. Also, one of the people responsible for the design and production of these monitors is a Canadian living in Winnipeg and a member here. Michael Gillespie....

http://www.preservationsound.com/?p=7156

hjames

01-05-2019, 12:46 PM

While I do enjoy the Lansing Forum folks and tech, you may have better luck asking at the Audiokarma forum.
Tho Fostex gear is not Lansing related - the only reason I mentioned it here was that I'd paired my Mid horn and tweeter with a JBL 2214 woofer in an Altec Cabinet -
My thread over there is at - http://www.audiokarma.org/forums/index.php?threads/fostex-horns-and-compression-drivers.809024/

And, Fostex Monitor guru Michael Gillespie wrote me from that thread! (very nice guy!)

But he does have a Pro Monitors thread on the Lansing site here -
http://www.audioheritage.org/vbulletin/showthread.php?5229-Mystery-Large-Format-Monitors&p=170945&viewfull=1#post170945

The user Earl K mentioned that someone here might be able to help me out so I will repeat my question here, thanks in advance!

can anyone provide Crossover schematics for one of the monitor models? I just bought a near NOS pair of T825 and FD600 and would like to try the original crossovers from the monitors.:)

best regards from germany

badman

01-07-2019, 09:20 AM

(Oh, I had mentioned at one point I emptied a pillow of Polyfill into each cabinet and extened the bass response of the "Valencias" - here's the pic)

Old post BUT!

If you're still using these, or anyone else will be, the polyfill situation should be adjusted. You definitely don't want the batting between frame and cone, and even moreso between cone and leadwires. This will lead to extraneous noise and distortion and even driver damage. A mesh or "net" around the back of the driver will keep the poly from getting where it doesn't belong (or use a different material that is more cohesive).

hjames

01-07-2019, 12:12 PM

Indeed - I made a fiberglass screen "shield" around the 2 woofers to keep the fill from getting into the speaker proper.
Actually, I switched from polyfill to a measured amount of raw lambswool, based on feedback from my audio guru,
who explained he'd had significantly better luck with lambswool.

83139 83140

Old post BUT!

If you're still using these, or anyone else will be, the polyfill situation should be adjusted. You definitely don't want the batting between frame and cone, and even moreso between cone and leadwires. This will lead to extraneous noise and distortion and even driver damage. A mesh or "net" around the back of the driver will keep the poly from getting where it doesn't belong (or use a different material that is more cohesive).

badman

01-08-2019, 08:55 AM

Indeed - I made a fiberglass screen "shield" around the 2 woofers to keep the fill from getting into the speaker proper.
Actually, I switched from polyfill to a measured amount of raw lambswool, based on feedback from my audio guru,
who explained he'd had significantly better luck with lambswool.

Good deal- I know you're experienced but we all make mistakes and it'd be a shame for such a simple thing to be overlooked. I've heard similar reccs re: lambswool. I really like ultratouch recycled denim batting- easy to work with, holds itself together, etc, and performs similarly to itchy fiberglass.

Dr.db

02-01-2019, 01:16 PM

80254

Just as an idea, but how about rotating the enclosure upsidedown. That way the 2214 would be much closer to the horn.
Right know these two sources are spread far apart and might not match up well...

vita

06-25-2019, 10:01 PM

Hello,
If it helps, the original filter of my LS3, it is not complicated.
Best regards

robertg

08-07-2019, 02:34 PM

Kreativlos

12-10-2020, 04:11 PM

Are Fostex diaphragms available any more? I can't seem to find anything with a Google search. I'm dealing on a pair of D252 drivers, but if I ever blow one they become pretty worthless if I can't get a diaphragm. I have a pair of pine H425 horns.

Nope no diaphragms available, so be careful. Pictures of your Horns and drivers would be great!

Best regards