| Buschhorn MkII w/ Foster W422, aka Fostex FE103A - Click HERE for Original Thread |
| DRCope |
I know a few of you have used the older Foster driver with alnico magnet in the BHorn II, and since I now have a pair coming my way, I was wondering what tweaks you have found work best with this particular driver. There's next to no specific info on this driver out there, and I do plan to do some experimenting of my own, but I'd love to do so with a base of information to stand on to begin with.
The speakers will be wired with Audio Note SPa silver cable and driven with a 2A3 stereo amp I have yet to build (Quest Silvers applied gently in the mean time), and an Audio Note Kit Pre or M3 Phono at various times. The front end is either an AN CDT Two MkII and DAC 3.1x Balanced or a Voyd Table, AN-1S arm and IQ3 or IO 1 cartridge and AN-S3 mc xfrmr. |
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| chrisb |
If you bought the drivers from Dave Dlugos (Planet10) without the wooden phase plugs, shame on you. :xeye:
If not, order a set of the plugs straight-way.
He and I have used this driver in various enclosures over the past few years, ranging from Bert D's cute little folded TQWP, Fostex's factory recommended ( Nagaoka designed) BLH "type", to the Buschorn. I may have missed a design or 3, but I think it's dafe to say that the best we've heard them is in the BHII.
Since you're reasonably assured the drivers are fully broken in (after only 30 or so years), there's really only a couple of tweaks needed;
1) Did I mention phase plugs? These made a huge difference in my system ( EL84 triode/PF monoblocks); opening up the midrange significantly and dramatically improving the off-axis dispersion, image stability and depth. We experimented with "helper" tweeters above 10K, but with any reasonably decent front end, and a SET as transparent and dynamic as EL84 or 2A3, it was hardly worth the trouble. (300B amps could be another story)
2) Apply a thin layer of Duct Seal ( Ideal Industries 31-601) to the stamped frame, in particularly filling the gap between the rear of the basket and magnet loop. The goal is to make as smooth a transition as possible. Maybe Dave can post a picture of a suitably modified driver.
The enclosures themselves benefit from sand filling of the large internal and lower fold voids - a little harder to install after the boxes are glued up, but where there's a will .... I used "Tru Grit" (really) sand-blasting abrasive.
If you haven't built the boxes yet, don't waste your time with any material other than Baltic Birch. Due to the amount of bracing from the internal folding panels, you could probably get by quite nicely with 15mm (approx 5/8"). A small hardwood or 3/4" brace across the final mouth of the horn doesn't hurt either, and makes for a convenient hand-hold when moving.
The trickiest part of voicing the speaker is damping the compression chamber. Some folks have experimented with blocking it off entirely when using the FE108E Sigmas, which I had myself, until very recently. I didn't care at all for the results, and went back to about 2/3 stuffing with 1/2" acoustic felt (also from the "frugo-phile" audio recycling guru), but YMMV.
As for placement, I have been happiest over the past 5 years or so with a placement diagonal across a room corner; i.e. the line forming the front baffle of the enclosures forming the base of an equilateral triangle, with the corner as the apex.
Due to the rear mouth of the BHII, you'll need to experiment with distance from the side walls ( I'd suggest starting around .5 - .75M) and toe-in.
Enjoy, and smile when your guests ask where the "other" speakers are
:D |
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| DRCope |
Actually, these aren't coming from Dave, but I tripped over his site, and it was in ordering the phase plugs that he informed me that the drivers weren't what I thought they were. Once the drivers get here, I'll measure and order up.
Nope, cabs aren't built yet, and I've read through your site, Dave's and a few others. Baltic birch was a given from the get go. I don't want my music to sound dead, which is what I always hear from MDF.
Sand is in the picture, as will be outrigger spikes since this speaker can't possibly be really stable on carpet.
Yeah, I can see from reading up that fine-tuning the size and damping of the cc will be critical. One side will be screwed on and finishing will have to wait a while. ;-)
Strangely enough, the speakers I sell in "real life" are designed for corner placement as well, which always gets the high end crowd's shorts in a knot.
These speakers will probably go with me to the Great Plains Audio Fest April 29 - May 1 in Tulsa OK. By tomorrow the beginnings of the site for the show will be up at www.greatplainsaudiofest.com |
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| planet10 |
Welcome o the forum Dave.
| quote: | Originally posted by DRCope
Strangely enough, the speakers I sell in "real life" are designed for corner placement as well, which always gets the high end crowd's shorts in a knot. |
More later... gotta go fix a set of isophone coaxes...
It is syncronystic that the local hifi dealer is a big AN fan/seller... Chris has built up a couple of the boxes for the kits.
dave
Cal's 10F3s with the major teaks....
dave |
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| planet10 |
And speaking of Cal's FE103As.... here is a pic of them in his new "Jimmy Buffet" 4-ways (or maybe 3.5 way). They are actually just place holdng for a pair of Coral 103As which -- unmodified & with a bit of "stiff surround syndrome" -- he liked better than the tweaked Fosters. His Corals are over here for surround resurrection and tweaks including phase plugs.
Dave's 103As, to my best guess, are also Corals and very similar to Cal's, the prime difference being the baskets.
Also of note in Cal's JBs are the Foster inverted dme tweeters. These are the only ones i have ever seen and look really nice (and Cal says they sound really good too)
dave |
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| planet10 |
Here is a pic of the Corals (i'm going to call them that, but still have some suspicions they may actually be Panasonic/Matsushita -- note that these were the guys that pushed FR tech the furthest of any of the big 3 OEMS)... note what looks like may be the points of ribs sticking out from under the dust cap)
dave |
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| planet10 |
Here is a pic of a larger driver with clearer ribs... if after removal of the dustcap there are ribs in Dave's 103As that is a very good thing and makes them very special...
dave |
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| planet10 |
And here for comparison are some known Coral 103As -- these are 8 ohm Sony labled ones, Cal's are 16 ohm Monarch labeled ones.
dave |
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| planet10 |
And Chris' B-Horns (before finishing) with Foster FE103As
dave |
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| planet10 |
And while showing variations, an Akai labeled Panasonic OEM.
dave |
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| planet10 |
and a group photo... mostly Foster FE103As ... of special note are the set on the lower right, these are a Canadian made Radio Speakers of Canada variant found i a set of the trendy Electrohome speakers -- unfortunately foam surrounds that are now dust. Since this pic was taken i've gotten at least 3 more flacvours of Corals (2 of those are singles), 2 more flavours of Foster, and the Panasonics above. Dave's are another i haven't seen. I mention numbers because this is probably fairly representative of the population distribution.
dave |
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| planet10 |
FE103As in BK101s -- for anyone tempted to build these, you might as well just put them in a sealed box (except these are cooler looking) -- that said, these speakers in my lab are one of the most useful speakers i've ever owned... the jacks on the front are very useful.
dave |
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| planet10 |
And we tried them in an aperiodic box (with a RS 40-1197 on the back for baffle-step compensation).
dave |
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| planet10 |
and here they are in the Fostex FE103 recommended horn... these need work. They have a "closed-in" character in the mid-range that makes them hard to listen too. 1st thing we are going to try is apacer plate on the front to make the compression chamber larger (Chris B-Horns with FE108ES developed a similar charachter when he decreased the compresion chamber). The Tim Forman-style ML-Voigts with 40-1197s easily out perform them. (the vintage iMac is intended to become a digital music server, and the black box has the Peerless 8s -- the ones with the really low Fs).
dave |
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| planet10 |
So when we say that the B-Horns are the best we've tried, we have tried a few others.
Once Fuzzmeasure gets T/S capability (or the weather gets better) i will get a sample set of parameters and i have a bipole 103 horn bouncing around in my head that will get out sometime.
An early concept sketch attached -- it has evolved from this sketch.
dave |
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| planet10 |
I'll try to get some pics up tomorrow of the very cute FE83A :)
dave |
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| Ropie |
| quote: | Originally posted by planet10
the vintage iMac is intended to become a digital music server |
A bit off topic, but I was thinking of doing the same with mine. I wish I was proficient enough to work out a way to strip it down, get rid of the screen and fit all the remaining circuitry, HD and CD/DVD player into a 'hi-fi box' with an lcd display and proper audio in/out connections :scratch1: |
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| planet10 |
| quote: | Originally posted by Ropie
A bit off topic, but I was thinking of doing the same with mine. I wish I was proficient enough to work out a way to strip it down, get rid of the screen and fit all the remaining circuitry, HD and CD/DVD player into a 'hi-fi box' with an lcd display and proper audio in/out connections :scratch1 |
There is a chassis/kit you can get that stuffs it into a 1U rack-space...
dave |
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| DRCope |
Dave,
I see the ribs in the cone in the larger driver, but I don't see anything in the pix of mine either in the cone or the dustcap. I assume, if they're there, that they stiffen the cone with little weight penalty, which would make the wave launch more uniform. What about the resulting sound makes them "special"?
Geez, it's nice to have such a wealth of information and experience at hand as I dip my big toe in the FR pond!
Yes, Sound Hounds is a great hifi shop. Terry and crew are a class act and know whereof they speak. Careful, though. The E kits will spoil ya! ;-) |
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| Cal Weldon |
I was wondering when dave was going to get involved with this thread.
Hey dave, you posted pics of my unfinished Jimmy Buffett speakers. I haven't done the top grille yet. I will post when it's complete.
Cal |
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| planet10 |
| quote: | Originally posted by DRCope
but I don't see anything in the pix of mine either in the cone or the dustcap. I assume, if they're there, that they stiffen the cone with little weight penalty, which would make the wave launch more uniform. What about the resulting sound makes them "special"? |
There is just a hint that they maybe exist under the dustcap... these would be akin to the ridges in the cone on the Fostex ESigma drivers. Those 5" & some 8" drivers with similar ridges are pretty special sounding.
Geez, it's nice to have such a wealth of information and experience at hand as I dip my big toe in the FR pond!
| quote: | | Careful, though. The E kits will spoil ya! |
Been listening to them and their bigger brethern for nigh on a year now -- no temptation at all (we have a Friday afternoon coffee klatch at Sound Hounds every week -- BTW it was Don, Terry, & myself that "launched" Sound Hounds in the latter half of the '70s)
dave |
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| planet10 |
| quote: | Originally posted by Cal Weldon
Hey dave, you posted pics of my unfinished Jimmy Buffett speakers. |
Do you want me to post construction pics & make it a series :^)
Unfinished they look pretty nice (i prefer them with no grills)
dave |
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| chrisb |
| quote: | Originally posted by planet10
Been listening to them ( the E-Kits) and their bigger brethern for nigh on a year now -- no temptation at all (we have a Friday afternoon coffee klatch at Sound Hounds every week -- BTW it was Don, Terry, & myself that "launched" Sound Hounds in the latter half of the '70s)
dave |
Nothing particularly exotic about the cabinet construction, or that matter the fairly normal looking SAES drivers (untreated paper cone mid/soft dome tweeter) and handmade XO.
As Dave said, we've had occassion to hear various combos of almost every AN (single box) speaker models, including silver wired specials etc, on comple AN systems ranging to over $120,00
Wonderful sound yes, "spoil" me for my own system, I don't think so. At the high end the pricing is (let's be charitable) - more than I would consider spending, regardless of my financial situation.
FWIW, I've been a customer, and regular of the Friday afternoon &"smoky" evening /afterhours club there for most of the past 30 years myself. If I've learned only one thing from the experience, it's that I have to trust my own ears, and not have to justify my opinions to anyone. |
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| DRCope |
I may be wrong, but you seem rather upset and I have no idea why.
Perhaps I should have included a little smiley face after the "spoil" remark. By and large it was supposed to be humorous - tonue in cheek. On the other hand, I chucked a perfectly good job to do what I do now because I capped a used AN system with a pair of E's. Stood my life on its ear. :hot:
I'm setting in to build a set of FR speakers, so obviously I think it's worth doing.
Nobody asked you to justify anything.
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| chrisb |
That does read a little ****y doesn't it? :xeye:
All I was trying to say is that I've heard good DIY or "sub-cultre" systems ( Bottlehead, Decware, Cain & Cain , Horneshoppe Horns, Omega, several DIY amps & speakers) that achieve 95% of the musical smiles, which cost less than one of the sales taxes (7%) on the interconnects and speaker wires in the dealer's "salon" demo rig.
Regardless of the nameplate on the gear, I just find that kind of pricing , if not obscene, at least not excusable.
Rant off :cannotbe: |
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| Cal Weldon |
| quote: | Originally posted by planet10
Do you want me to post construction pics & make it a series :^)
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Sure, I'll forward the rest to you. The grilles are being made today. |
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| DRCope |
Dave - I've downloaded the fuzzmeasure, and there's much esoteric discussion about it, but what I can't find is an explanation as to how it actually gets USED! How do I get the test signal out to the system - surely not through the headphone jack! What should I use for a mic, and how does it get back into the Mac? The notion that no additional hardware is required, but I don't see how that's possible. . . . :confused:
Help! |
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| planet10 |
| quote: | Originally posted by DRCope
I've downloaded the fuzzmeasure, and there's much esoteric discussion about it, but what I can't find is an explanation as to how it actually gets USED! How do I get the test signal out to the system - surely not through the headphone jack! What should I use for a mic, and how does it get back into the Mac? The notion that no additional hardware is required, but I don't see how that's possible. . . . |
What Mac do you have? By no additional hardware i think Chris really means "no additional computer hardware". If your Mac has a mic input you can at least use the Apple PlainTalk mic (ie on my old PowerBook i used this with mac-the-scope). But my G4 only has a line-level input so i need a mic pre... the Griffin iMic is an option, a more serious mic pre can be bought from a number of vendors, BrianGT & Vikash are putting together a mic pre group buy (boards at least) based on the Neal/Wallin design (my V1 board from Neal attached -- assembled, not tested).
To do impedance you need a jig... a simple jig requires a 1k R, a stereo miniPhone cable, and a calibration R (ideally a similar R to what you are measuring (ie typically 8 ohms).
dave |
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| planet10 |
I built up a more elaborate jig... a DUT connection (with wire & alligator clips), a pluggable space for the nominal 1K R, RCA I/O,. the calibration R mounted in an easy to get to place (installed after these pics -- also doubles as an alligator clip dock), all mounted in an old Apple 400k floppy disk drive enclosure.
I plan an even more elaborate one with a switch and additional miniPhone jack so i can hook my 'puter speakers to the jig and switch between them and the jig.
dave |
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| planet10 |
and i promised a pic of the "FE83A" -- an 8F3 in this case...
dave |
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| DRCope |
Interesting. The whole thing looks really cool and useful.
However, I have a Titanium Power Book which has no audio input and only headphone jack out, so I suspect I'll have to add a USB sound card and mic. No huge deal I guess, but not an area I know anything about. Guess I'm gonna find out now though!
Thanks!
Dave C. |
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| planet10 |
| quote: | Originally posted by DRCope
I have a Titanium Power Book which has no audio input and only headphone jack out, so I suspect I'll have to add a USB sound card and mic. No huge deal I guess, but not an area I know anything about. Guess I'm gonna find out now though! |
You could always try using the built-in mic -- kind of awkward thou... this is where the iMoc is usually the 1st device -- it gives you a line/mic input (switchable) and a line out.
dave |
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| CrisTUFR |
Hi Dave,
| quote: | Originally posted by DRCope
Interesting. The whole thing looks really cool and useful.
However, I have a Titanium Power Book which has no audio input and only headphone jack out, so I suspect I'll have to add a USB sound card and mic. No huge deal I guess, but not an area I know anything about. Guess I'm gonna find out now though!
Thanks!
Dave C. |
Sorry the webpage for FuzzMeasure didn't help you out as much as it should have. I'm planning to put up a really detailed page on what you'll need for certain measurements once 1.2 is almost done. I've been working so much on adding features to 1.2 that I've had nearly no time to actually put some helpful pages like this up. :P
If you're looking to pick up a USB sound device, first make sure that you figure out how serious you want to get with FuzzMeasure. Also, determine if you want to concentrate more on acoustical measurements, or electrical measurements (although I'm sure the majority just wants to do both).
If money is no object, try to seek out a device called the USBPre. It's really spendy. You can probably get great results out of the Edirol UA-25, and it includes a microphone preamp as well.
Whatever you do -- don't buy an iMic for measurements. I will be posting something on my main weblog page in the next day or so about why it sucks pretty badly.
If I had the cash, I'd buy a handful of USB audio devices and run tests on them. Unfortunately I only have 3 at my disposal, so I will be sure to post every last dirty detail I can get out of all the devices I have here.
I hope that getting up and running for measurements isn't too painful for you. I have a lot of work to do in order to get the state of affairs with MLS software on the Mac sorted out! :)
Cheers,
Chris |
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| DRCope |
It won't be painful, and I'm thrilled that such a tool is available for OSX ! I'm just getting acclimated in a new area.
I'll be using it on Audio Note speakers, DIY projects, as well as taking it to the Great Plains Audio Fest in Tulsa, OK April 29-May1, and offering its services at a New England Bottlehead/Valve Club meeting later in May. It'll be interesting to see what kind of results I get! ;) |
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| DRCope |
So I start looking into the various USB mike preamps and realize fairly soon that with one more mic than I would need for measuring, I could record my church choir and who knows what all, which of course escalates the quality of the mic I "need". Oh dear, oh dear oh dear.
I fear another hobby (live digital recording) has just snuck up on me! :D |
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| DRCope |
Here it is only two months later and I'm baaaaacck. Since the last installment, I've taken up digital recording, (Presonus Firebox mic-pre,A/D, Firewire), Groove Tubes GT55 large condensor mikes, CuBase LE. I've recorded a couple choir concerts, and it now occurs to me that I haven't done the FuzzMeasure thing. Duh.
Meanwhile, the 103A's do appear to be identical or nearly so to the Panasonics Dave shows a way back upstream. They do have the ribs, too.
I FINALLY put them in pair of (borrowed) Fostex back horns (with the stair step effect in the mouth and on the face). They previously had a pair of Fostex 103E's in them, which sounded okay, but a looong way from great. The Pana103A's sound FAAARRR better, although still not great. Mind you, I don't have phase plugs or damping done, and the internal wiring is magnet wire. Since I have it on hand, the magnet wire is coming out in favor of 1 leg Audio Note SPe, one SPx per speaker.
The damping is a no-brainer, I just have to do it. I'm reluctant to peel the dust caps off to measure for Dave's phase plugs, however.
Oh yeah, I dismembered a pair of Soliloquy speaker stands to get the adjustable spike platform. The space between spikes allows a half inch on either side of the cabinets. Looks like it was made for it, and man, it is STABLE. I've never understood skinny cabinets wobbling around on carpet. Just can't be helpin' matters . . . .
Oh yeah - almost forgot - the amp I'm using is the Yamamoto A08 - 717A (little mushroom) pentode driver into 45 power tubes, 5U4 rectifier. 2 wacking big watts. Sounds flippin' incredible. Check out the review on 6moons, or at Venus HiFi, the U.S. importer.
Disclosure: Brian B at Venus Hifi is an Audio Note dealer and a friend of mine, but that has nothing to do with my mentioning this amp. It's superb, and a huge bargain. |
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| planet10 |
| quote: | Originally posted by DRCope
Meanwhile, the 103A's do appear to be identical or nearly so to the Panasonics Dave shows a way back upstream. They do have the ribs, too. |
I've since seen these with an Everlite brand name & had correspondence with a Japanese gentlemen eho bought some new, and says they are made by Atomix (they supposedly were one of the smaller OEMs building a lot of the drivers for Sansui -- which i've previously attributed to Coral or Panasonic)
dave |
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