Fostex flats from madisound

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Offline Paul Joppa

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Reply #15 on: May 19, 2010, 02:33:02 PM
... I still need the BSC schematic. ...
It's documented (just barely!) on teh SEXy Speaker page, under Community.

Paul Joppa


Offline Dyna Saur

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Reply #16 on: June 19, 2010, 05:51:33 AM
I built a pair of the Madisound BK-16 kits (and Fostex  FE165K drivers & T9A supertweeters. Very nice sounding, and surprisingly good bass from a relatively small diameter driver.  I won't attempt to wax poetic about the mystical sound qualities ;-)  They took around 100 hours to start sounding "right" and have improved with subsequent use.   I have not yet finished the cabs, they are still teh natural wood (Baltic Birch plywood).

Here's a shot of the system:

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fpictures.insulators.info%2Fpictures%2F47%2F223744000.jpg&hash=8b81bff553a8f766039025b5929a66dc71de98e4)

The rubber yellow  frog and blue lizard add nothing to the sound quality ;-)

and a close up of the Paramounts and FPIII modified to use 6SN7s, a stepped attenuator, and only one set of inputs.  The CD player (Rotel RCD85 is "hidden" in the cabinet under the amps.

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fpictures.insulators.info%2Fpictures%2F47%2F223743609.jpg&hash=aa4f29ee39baea6ac82c4c68105bd766067b0444)


I am considering purchasing a pair of the BK-20 flats, to use with my FE208Es.  The prices on these cab "flats" has risen considerably over the past couple of  years...    I wonder if the plastic  phase plugs from DecWare may do the 208s any good (not the same as their original phase plugs which were hex  socket wrenches)..

/ed B in NC

« Last Edit: June 19, 2010, 05:58:25 AM by Dyna Saur »

ed brown


Offline kip.duff

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Reply #17 on: November 07, 2015, 02:15:34 PM
Putting together my Paramount 300B's.  My first SET, so the search is on for a more efficient speaker.  At some point, I will get Altec 604 8H speakers with as yet to be determined enclosures using Jeff Markwart's XO design..  At present time I don't have space- and if I did, I'm not sure the Altecs would work well in a smaller sized room.  Other than in the case of the Altecs, I'm a believer in smaller full range speakers- my current set and by far best speakers I've ever had are a knock off of the Bowers & Wilkins 805 SD tear-drop shaped speakers.  But not efficient enough- I wanna try something new anyway.

So: I almost ordered some BK-16 flats and Fostex FE168E Sigma's from Madisound- but in reading up, I noticed that not a lot of people were ecstatic about these- some were somewhat underwhelmed.  The BLH design is very interesting, and I'd love to try them- but I've never heard them.  I don't have the time or workspace to play carpenter at this time, so the flats are attractive because of ease of assembly.  My vinyl system is already a little aggressive in the mids and upper mids (seems to be a common complaint), so I gotta be careful.  Internet streaming off Spotify thru my Mac Mini and DAC (no preamp) is well equalized and sounds great.  I am aware of the BSC options (saw a lot about this in some big DIY threads about the Tang Band 8W-1772 full range speakers).  Sounds like a BSC might be helpful with the BK-16/Sigma set up.  I'm looking at the 6.5" design because I believe may be better in a small room.  Also looking at BIBs and simple bass reflex box Godzilla built.

You guys that have them, what do you think?  Advice from anyone welcome.  Of course, I'm also searching AA High Efficiency forums.  Much thanks, Kip................

Dr. Feickert Blackbird II w Reed 2A tonearm and Lyra Skala cartridge.  Eros 2.  Audio Note DAC 2.1 Signature.  BeePre with BeeQuiet and Paramount 1.1 monoblocs into A7 VOTTs or Nagoaka folded horns.


Offline Paul Joppa

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Reply #18 on: November 07, 2015, 02:44:59 PM
Before the SEXy Speaker, I made a 1.0 cubic foot reflex box with FE167s. We thought there was too much excursion demanded, causing an overload congestion whenever there was a lot of deep bass, so the SEXy put the same driver in a smaller 0.25cf sealed box and specified a subwoofer per channel crossed pretty high. So I have my doubts about 6.5" Fostex drivers in ported boxes, unless you are listening to music without heavy bass, i.e. small jazz ensembles and chamber music.

Back-loaded horns usually have very small mouths relative to the wavelength at low frequencies, so they have uneven response. Of course most rooms also have uneven response due to room modes, so that is not always perceived as an issue. On the plus side, the horn load on the back of the diaphragm can be more efficient than the direct radiation from the front, producing the BSC effect naturally. I have not tried a detailed design, not do I have more than a very little experience listening to these, but I expect that they can be capable of excellent sound if well designed.

My two cents.

Paul Joppa


Offline Bill Epstein

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Reply #19 on: November 08, 2015, 10:42:57 AM
I owned and them.  Great mid range and imaging that a single driver can give but that's about it.  The 166's with the whizzer cones hurt my ears.  I had better results with the 165 drivers in near field.  I couldn't get any lower than 50 Hz out of them and it was way down dB.  I wasn't running tweeters with them and they rolled pretty heavily after 9 or 10k Hz (memory slipping).  Replaced them with Altec Model 19's and haven't looked back.  As a note, the cabs are not as easy to glue together as they may seems.  If you don't have plenty of extra clamps, you may want to consider having a carpenter glue them up for you. 

The experience with them has inspired me to try a higher quailty single driver full range or even a two way OB set up with active crossovers, someday....  Good luck and enjoy!

Back when a Foreplay 2 was $149 and Paramours had just come out the Fostex 104E was enthusiastically endorsed here and elsewhere as a great value in the Fostex recommended enclosure. I built it and thought, like Johnson, that the mid-range was superb, the imaging other-worldly but the treble made it overall sound like an AM radio.

I know that newer 6" and 8" Fostex drivers sound quite a bit better and have heard Bob Brine's speakers, with BSC crossovers, sound very good. In addition, the Fostex cabinets are far easier to build than they look, even to a Tyro. I came up with a construction method that others have found easy to use for their labyrinth horn projects.

First, forget about how many pieces there are to cut; they're all the exact same width. One rip fence setting does them all. In fact, you MUST cut them all in one session or somehow not let the fence move in between cuttings so that they're all exactly the same width. Once you rip all your plywood a chop saw with a stop makes quick work of each set of the various sizes.

 After I cut all the pieces to size I  placed them on one cabinet side piece and traced the positions with a soft lead pencil. Then I shot beads of construction adhesive from a tube, Liquid Nails, PL400, whatever, inside the lines , took a piece of plywood larger than the actual side piece, laid it on top and weighted it with 2 -25 lb. bags of lead shot. After an hour, with the glue sufficiently set up so the pieces wouldn't move, I shot beads of glue on the tops of the baffle pieces, laid the remaining side on top and weighted that. Finally, I nailed #4 finish nails, just a few, around the perimeter, countersunk them, then flipped the cabinet over and nailed that side. This last probably wasn't necessary but made me feel better ;-} I also glued on thin strips of Mahogany to cover the exposed plys.

This will of course work equally well with the Madisound Flat Packs. Also, before there were Home Depots and Lowes every neighborhood had a lumber yard and many still do. Provide one with a cut list from the Fostex plans and for a fee, they'll cut your plywood to size and sell you the glue and nails. Then it's off to the Hunting Supply for Lead Shot. 


VPI Traveler/ZYX R50
Cinemag 3440 AH
Steve Brown Caravaggio Phono
Foreplay 2.1
The Twins: 55 Watt Mullard 5-20 KT-88 mono-Blocks
4 Pi Speakers


Offline kip.duff

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Reply #20 on: November 11, 2015, 09:26:31 PM
Paul:

"On the plus side, the horn load on the back of the diaphragm can be more efficient than the direct radiation from the front, producing the BSC effect naturally."

So, in theory, a BLH design would not need BSC. 

What are you happy with for your system?  I think you mentioned you had JBL's?  I've seen a lot of positive opinions about Altec 604 series setups- but little about JBL setups.  Because I don't have large listening area, I've ruled out large speaker diameters and/or enclosures for now.  That will change soon when I move.  I don't listen to "jazz ensembles, chamber music" usually- I'm not against fat juicy, colored, bass- as longs as it's separate, clear, and "in the air".

Thanks so much for taking time to respond, Kip...........

Dr. Feickert Blackbird II w Reed 2A tonearm and Lyra Skala cartridge.  Eros 2.  Audio Note DAC 2.1 Signature.  BeePre with BeeQuiet and Paramount 1.1 monoblocs into A7 VOTTs or Nagoaka folded horns.


Offline kip.duff

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Reply #21 on: November 11, 2015, 10:10:31 PM
Bill:

I was gonna build (or have built for me) a Tang Band W8-1772 based BLH enclosure using Tang Band's BLH design from their site.  110 lb enclosure using 25mm Baltic Birch!  They also called for 1/4" felt for all of the interior surfaces except side walls.  Too big of a project in effort and $ considering that it's a unknown and has a whizzer cone.  Then I noticed the Fostex stuff.  The Fostex BK-16 is also an unknown, but cheaper and easier.  I don't know if you noticed, but they have grooves on the interior walls for precise assembly of  baffles.  I also liked that the throat was gradually tapered throughout by angling the baffles.  Pair of enclosures plus shipping about $360.  Not the end of the world if I don't like them.  Could use the drivers in other enclosures.  The Madisound BK-16 enclosure is not like the Fostex recommended enclosure for either the FE168En or FE168E Sigma.  I'm curious to know who designs and produces these.   I had already thought of an assembly method similar to yours- two very flat boards with the speaker enclosures sandwiched between.  Several cinder blocks on top.  This technique would apply even pressure- not localized like with clamps.

"....but the treble made it overall sound like an AM radio."

Sigmas now have high tech-looking phase plugs and strange star-shaped ridges on cones- hopefully mitigates this issue.

Based on the review you quoted by Johnson and some other reviews, I'm gonna do more research before jumping in with the BK-16.

Dr. Feickert Blackbird II w Reed 2A tonearm and Lyra Skala cartridge.  Eros 2.  Audio Note DAC 2.1 Signature.  BeePre with BeeQuiet and Paramount 1.1 monoblocs into A7 VOTTs or Nagoaka folded horns.


Offline kip.duff

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Reply #22 on: November 11, 2015, 10:17:24 PM
Bill:

Also noticed the the enclosure in the lower of the two images you posted is not the same as the current BK-16, or any of the current Fostex designs for the FE168E's.

The upper image is not like any enclosure I've seen.

What speakers are you liking for your (I'm assuming you have SET amp) current setup?

Thanks, Kip............

Dr. Feickert Blackbird II w Reed 2A tonearm and Lyra Skala cartridge.  Eros 2.  Audio Note DAC 2.1 Signature.  BeePre with BeeQuiet and Paramount 1.1 monoblocs into A7 VOTTs or Nagoaka folded horns.


Offline Kris

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Reply #23 on: November 12, 2015, 03:49:43 AM
How about Frugel-horns flat packs from Planet 10 with their modified Fostex based drivers?
I don't own them personally, but I read really good reviews here and there online about them.
I was eyeing both Madisound and Planet 10 designs for a while and both look really tempting. Leaning towards Frugel-horns at the moment though.

Just my 2c.
« Last Edit: November 12, 2015, 03:52:12 AM by Kris »



Offline kip.duff

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Reply #24 on: November 12, 2015, 04:05:19 AM
How about Frugel-horns flat packs from Planet 10 with their modified Fostex based drivers?
I don't own them personally, but I read really good reviews here and there online about them.
I was eyeing both Madisound and Planet 10 designs for a while and both look really tempting. Leaning towards Frugel-horns at the moment though.

Just my 2c.

Thanks..... I'll look into that- didn't know about kits. 

Dr. Feickert Blackbird II w Reed 2A tonearm and Lyra Skala cartridge.  Eros 2.  Audio Note DAC 2.1 Signature.  BeePre with BeeQuiet and Paramount 1.1 monoblocs into A7 VOTTs or Nagoaka folded horns.


Offline kip.duff

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Reply #25 on: November 12, 2015, 06:25:59 AM
How about Frugel-horns flat packs from Planet 10 with their modified Fostex based drivers?
I don't own them personally, but I read really good reviews here and there online about them.
I was eyeing both Madisound and Planet 10 designs for a while and both look really tempting. Leaning towards Frugel-horns at the moment though.

Just my 2c.

Wow...  Been wandering thru various Frugal Horn, DIY, Palnet 10 threads for about an hour.  Couple of important things (for me anyway) I'm still not clear on with regards to Frugal Horns- maybe you know answers.

*are the modified Fostex drivers efficient enough for Paramounts (8w)?
*do they need to be placed back-to-the-wall? 

This is kinda off-topic, but thought I'd post it anyway- relates to Frugal Horns if they need to be placed near wall.  Every time I place speakers in conventional manner (close to rear wall, spaced somewhat far apart, firing-line perpendicular to rear wall), I don't like the sound.  Seems sound waves are getting jammed up somehow.  My technique for as long as I can remember is: speakers close together, currently about 3.5' and 6' away from rear wall/corner (depending on room size), towed in, firing line about 14 (?) degrees off the diagonal of the room (usually have been smaller, rectangular rooms- firing-line hitting shorter of the room's rectangular walls about 2-3' from opposite corner), and firing-line at ear level, parallel to floor (speakers not tilted).  Some sort of sound wave dispersion/relief effect for me.   I'll shut up now.......

Dr. Feickert Blackbird II w Reed 2A tonearm and Lyra Skala cartridge.  Eros 2.  Audio Note DAC 2.1 Signature.  BeePre with BeeQuiet and Paramount 1.1 monoblocs into A7 VOTTs or Nagoaka folded horns.


Offline Kris

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Reply #26 on: November 12, 2015, 06:55:29 AM
Why don't you just contact Dave from Planet 10 and ask him all your questions and concerns. It's always good to go straight to the source first.