Speakerlab Bass Bin

[tigerwoodKhorns]

I am going to look at a Speakerlab "k horn" tonight. It is a factory built unit that has the mids and tweeter in the front of the bass bin (I really can't picture how they did that.

Does anyone here have any experience with these?

What is the bass driver (is it the K33)?

Is the bass bin an exact copy of the K Horn (ie. is it a 400hz horn)?

Is the factory unit very well built?

I am replacing so much in my Tigerwood K Horns (Crossover, tweeter, midrange driver, midragne horn) that I may sell them as it appears that I only need the bass bin. I may wind up selling my K Horns.

What should I look for when I go to see them?

Any input is appreciated.

Thanks,

Chris

[D-MAN]

I am only familiar with the Speakerlab "K" made around 1978-1982 and I have the plans for the "K" purchased in 1980. It is a virtual Khorn knockoff on the bass bin, there are minor cosmetic differences, especially in the top cabinet. The crossover point is 400Hz, exactly what you would expect with a true "Klone".

I've heard that in the mid-to-late 80's, it seems that SL changed the K to a design that closely resembles the early Klipsch version of the 1940's which closely follow the original 1945 patent to PWK. This is a fine design that you can see here:

http://forums.klipsch.com/forums/632368/ShowPost.aspx

The only part that I do not understand is you reference to having the mid and tweeter "on the front" - I have not seen nor heard of this. The "K" had a removable top cabinet that sat flush with the bass bin (ala Khorn). However, there was a riser version that you could make or buy too.

The SL-K bass bin is a pretty close copy of the classic Klipschorn. Internally it is an exact copy right down to the 3" wide slot (only needed for the K33E). Therefore it can use the K33E just fine. However, the original Speakerlab 15" horn driver is a nice little number in its own right (it is 8 Ohms). Frankly, I think that its a better driver than the K33E and certainly outperforms one even with the too-small "slot" for it, but that's my opinion.

If I remember correctly it was a CTS driver, but I'm not sure. It has square magnets.

The part where the Speakerlab K cannot really compete in performance in my opinion is the stock SL crossover, which was a cheap rendition of what a crossover should be.

The top horns and drivers (Atlas mid/ EV35 tweeter) were stock and happened to be the same as Klipsch (well, if you're going to clone something - CLONE IT!). The SK version had an EV T-350 tweeter which is quite a bit better.

I never liked the appearance of the top cabinet of the SL-K, but all of the cosmetic issues could be addressed easily.

I believe that Gil McDermott built a pair or two of the Speakerlab K's - hopefully he'll chime in here, too.

DM

[tigerwoodKhorns]

D-man,

The seller told me that this is a later version where the mid and hf drivers are in the "front" of th espeaker and it is shorter than a K horn.

I can take some pics tonight when I see it.

From the above, it appears that you are giving me the thumbs up to purchase these. My plan is as follows:

Use teh bass bin with my false corners (the ones that look like Jubilee cabinets), use Al's ESN network, Altec 511B's w/ JBL 2470 drivers for mids and Jbl 2404 baby cheeks for tweeters. That being said, teh only thing that I am interested in is the bass bin and the woofer, which you are saying is a good unit.

One question though, doesn't the modern K horn bass bin (post early 60's) use a wider slot and isn't it supposed to have better bass?

Finally, what driver is used in the Speakerlab bass bin?

Thanks,

Chris

Quick edit: Which slot are you referring to? The slot directly in front of the driver or the slot at the back of the cabinet where the sound exits the bass bin?

[D-MAN]

I don't know if I am recommending it!

It doesn't sound like anything that I'm familiar with.

The K I am referring to is a knock off of the Khorn - it is the same exact size as the Khorn. However, if it lacks the top cabinet (which it sounds like, having the mid/tweeter mounted on the front of the "bottom" bass bin), then I suppose that could be what is meant by it being "shorter than a Khorn".

It is just the bass bin, of course, so that makes some sense. It should be around 39-40 inches tall, if that is the case.

However, it is certainly worth a listen and look-see. If you like it, you should get it.

By all means post some pics! It sounds interesting.

The SL woofer that I'm familiar with was a WP1505 (from memory-don't hold me to it). I think that it was originally from CTS; square magnet, very heavy. It is a nice horn driver, I've heard more than one. It is 8 Ohms, so your current crossovers will need some tweaking. It will flap your pant legs, guaranteed. So if the drivers are in good condition, that is a bonus.

DM

[D-MAN]

Waitaminute! I HAVE seen one of these on EBAY once. It had a tweeter mounted through the front panel.

I didn't realize that it was a later Speakerlab model, and it might have been. I thought it was a modified Khorn bass bin.

I have one reservation about it, providing we are talking about the same thing (which I am still not entirely sure about). There is not enough room to mount both of your horns through the front panel as far as I can see.

Here is the design of the Khorn, and you can see the limitations on horn size and placement if you are going to mount the mid and high frequency horns through the front panel from the back chamber. This presumes the same internal design as the Khorn...

The problems I see are:

==================

(1) the tweeter/mid horns would be too low to the ground for "best" dispersion when mounted as described above (i.e., halfway up the cabinet). Also there would be one on each side of the cabinet.

(2) If mounted in the upper throat channel (i.e., a better choice for dispersion characteristics) then there would be an obstruction in the upper throat channel. Granted MANY speaker designs do this very thing at the mouth, BUT not in the throat!

The EXCEPTION to this would be that the design in question is NOT the same as the Khorn - if it folds HORIZONTALLY rather than vertically like the Khorn, it certainly would have room for the horns and drivers in the back chamber. For instance, that approach would work fine in a horn like the Jubilee or mine. I personally don't like fixed high frequency horn angles, though.

DM

[tigerwoodKhorns]

How many ohms is the K33?

What has to be done to an ESN to accomodate an 8 ohm load on the woofer?

Chris

[D-MAN]

{Edit}: the K33E is 3.2 Ohms (figure 4 Ohms). The standard ESN is configured for the 1 mH VC inductance (Le) at 6 Ohms (due to horn loading). An 8 Ohm driver will have a different Le and be anywhere from 10-14 Ohms when horn loaded.

More thoughts on flush mounting drivers in the bass bin....

For instance, if it looks like this, it is entirely possible to mount all drivers into the bass bin at a reasonable height to have pretty good coverage at average listening distances...

This drawing is a hack-job of the Khorn patent making it a unitary throat that bifurcates at the tailboard. It retains the vertical throat only in one direction. It would also be set-back from the front panel further than the drawing shows (6" vs. the standard 3" when bifurcated at the throat).

DM

[tigerwoodKhorns]

I'll just build a top enclosure like the K Horn for the ALtec and JBL stuff.

Is this horn a 400hz model?

Chris

[D-MAN]

I don't know - I'd have to see it to be sure.

It sounds like it might be a different design than the Khorn "Klone" that I am familiar with.

If its a "Klone", then yes, it is a copy of the Khorn bass bin and everything is the same as the Khorn (operationally speaking). All stock Klipsch components would work fine in it.

One more question - if you build a top cab, what about the hole in the front panel for the tweeter (which you won't need).

It is not a good idea to have the horns and drivers widely separated due to comb-filter distortion, so I assume you would remove the driver from the front panel?

DM

[Duke Spinner]

more than likely, it has a Speakerlab OEM driver made by CTS....

hey, ifn' thier reasonable ...how can you go wrong ...

some of the S.L stuf was great for the price ,....

[WMcD]

Since DM invited me to comment, I am pleased to. The below rambles a bit.

Actually I built some using 3/4 inch ply, pretty much from scratch. I made the midrange horns from plywood. I'm planning on donating them to my high school but expect the shipping costs will be very high. OTOH the young geeks like I was might enjoy playing with them.

But about the SK's. I have three friends who built the kits. I can give some thoughts based on that.

The tweeter in the SK fits at the side of the midrange, rather than on top. So the top is not as tall.

There were at least two tweeters available. A T-35 (extra cost option) and a smaller unit which was not as sophisticated.

The early ones came with a fiberglass mid. Later there were metal ones.

The woofer in the one I've seen open looked like a very small magnet, in memory. Other people describe something different. So there may have been various woofers used over the years. Bruce Edgar had unkind things to say about the woofer.

I recall that some SK bass bin kits used particle board, others used fir ply. Assembly instructions show the use of nails rather than screws.

I have a schematic for a crossover, someplace. I could find it. It shows the use of two L-pads. The crossover I've seen in the flesh has two switches with resistors. The schematic shows a first order bandpass for the mid. I also have the cutting and assembly plan if someone wants it. My suggestion, though, is to build a Jubilee.

The SK, is mentioned in a Dope from Hope, but not by name. You can search the forum for the words free and dope and hope. The collection I posted willl show up.

- - - - -

PWKs best argument was that kits had no QC and even the factory built didn't have the same frequency response as his. He even commented unfavorably on licensed units.

I believe the major appeal of the SK kit was that people wanted to build them, themselves. PWK at one time encouraged that. Later he changed his mind, apparently. He didn't like his name being used on other's commercial projects.

Back then, places like Heathkit and Eico had electronic kits. Those products were a decent value or advanced in features. Of course some people would have paid extra for the experience. You really learn about electronics. I built a dozen at least. That is a bit OT, but you should know the zeitgeist back then. There were licensed kits of other Klipsch products.

I don't have bad things to say about the SK technically. It shares so much with the K-Horn that it is must have many of the same merits. On the other hand, it does look home make. The Klipsch products are works of art.

One part of the SK assembly instructions says "there is no problem (sealing and gaps) so bad that it can't be filled with RTV." That could be taken as admission that problems are likely to occur. OTOH, it shows that sealing is known to be important and must be remedied. On that subject, the EV Georgian instructions describe a test for back chamber seal using a water and tube manomometer (OT again).

Another issue is that the SK cutting instructions show that it backed away from using the top and bottom wedges as a an extra volume for the back chamber. More than I can explain here. PWK had commented on SL following Klipsch mistakes. But I think the Klipsch unit does continue to use that feature. Maybe not using it was the mistake.

You may have seen a picture of PWK standing with the Plexiglass KHorn. There is a notch cut-out to be seen so that there is communication between the back chamber and the wedges. You'll recognize the picture by the fact that PWK is wearing socks and sandals. He was never a slave to the fashion demands of Arkansas. Smile. This issue (not footwear) is related to driving down system resonance. SL may have been correct to not use this. Sealing and glueing is bear with it.

As far as the wisdom of a purchase of an SK, I myself would stay with Klipsch in view of its enduring value and quality of construction.

OTOH, you might want to buy an SK if the price is right. Also, if you want to tinker and not compromise the value of the Real McCoy, it would be worthwhile.

I don't know about squeezing K-400 mid horns into the bass bin. I looked at it and concluded that there just was not the space. People may be talking about "front mounting" to mean how, rather than where they are placed.

I'll be happy to answer any questions, of course.

Best,

Gil

[ajsons]

This is the Speakerlab khorn clone later model, or the "New K".

[ajsons]

I'm sorry for the size of the picture.

A sub-assembly, or additional enclosure 3" deep is attached to the front of the bass bin, and houses a 7" cone midrange driver (Audax???) and a t-35-like tweeter. The crossover is at the lower half of this subassembly. The bass bin is the same as the first clone Speakerlab made except the sides are chopped off making the bass bin only 23" wide. Also it has no tailboard. The bass response, as one might expect, is a little disappointing. (I built a pair of the bass section, with EV components (EVM-15L, 1824 mid, SM120 horn and T-35. My University Classic performs much better in the low end!!).

I'll post the sub-assembly plans and driver info when I figure out how to reduce the size. Somebody please tell me how.

[tigerwoodKhorns]

Here are some pics. They are teh same as Armando's.

Duke, is this the driver that you referred to?

If so, is it 8 ohms? (I can go measure it).

I am considering using an active crossover for this and tri-amping. What do you reccomend.

I am considering teh Behringer (not likely) a Rane unit and an ashley unit. What do you guys think?

Chris

[D-MAN]

Guys, there are no pics!

(.jpg seems to upload ok and .bmp won't).

DM

[tigerwoodKhorns]

[tigerwoodKhorns]

[tigerwoodKhorns]

[tigerwoodKhorns]

[tigerwoodKhorns]

I still need some info on active crossovers. I want to get an Ashley unit. What do you guys think?

Is a digital unit superior to an analog unit? The Behringer unit is about $250 but I feel that the Ashley unit is probably a much better unit.

Chris