homemade

BTW: Zenith produced stereoes in the late 70's that had nondefeatable loudness controls. My brother sold his Zenith "wedge" to a friend and I sold the friend some speakers I had (12inch alnico woofers that went flat to 30hz in a big ported enclosure) and were fairly efficient and the bass these put out were great with just 12 watts per channel. I've got one of these "wedges" for our shop and some day will hook it up when the old admiral stereo gives up. If anyone remembers these "wedges"-it was one of the first major electronics companies that started to produce a decent stereo setup. This one had a built-in 8 track recorder (possible with dolby-can't remember for sure), tuner knob that had some flywheel effect and decent 10inch ported speakers. Didn't sound bad compared to the other store bought all in one units at that time.

I always enjoyed using the loudness control on my old JVC reciever but Yamaha no longer employs it and I'm pretty sure most other receivers don't have it now either. What a perfect way to get some bass from the bass shy Klipsch Heritage speakers. The only problem is that the efficiency is so high on these models that the built-in loudness compensation ends up boosting too much at the higher volumes. Most loudness controls were designed to have no effect once the volume passes the half way point but my homebuilt khorns seldom need volume above the 1/4th way and 1/2 way up I'm looking at 120db in the middle of the room with a 60watt amp!

Perhaps the Audax PR17 is available in a 4ohm version and only one per speaker would be needed. I've seen another manufacturer offer a similiar driver for around $50 I believe (perhaps Eminence?) What's the opinion of a midrange cone driver like this compared to a horn loaded one? No resonance problems, etc. BTW: I've used my PR17 with a 12db crossover at 400hz with 200 watt amps without any problems but than again I don't keep it turned up for any length of time-only as long as my ears can take it! I suspect my ears go into overload before the driver does in a smallish room.

I'd be curious how a pair (to increase efficiency by running them at 4ohm) of Audax 7inch high efficiency cone driver (99.6 efficiency) would compare. I'm using one in my homebuilt khorn and it mates up efficiency wise pretty close because I'm using an 8ohm bass driver. I think they are a suberb midrange driver but I have no experience with the khorn midrange horn sound.

djk, how did you work out the efficiency difference between the Motorola piezo (92db ) and the khorn? It looks like the tweeter (from Radio Shack though) I used with some homemade Bose 901's to sweeten up the top end.

I built an original 901 from the patent papers that speakerlab had in the mid 70's. I never did have the proper eq. (there was an eq. schematic in the patent papers) but used a 10band eq. which worked fine. You had to increase the lowest 2 octaves 12db (I also had to eq. the lowest octave on the mighty khorn also) and upped the highest band eq. by 12db (15khz). They were ok but the bass still lacked for me. Nowadays one would just add a subwoofer to fix the lower end problem. The early models (before the plastic housing models) were touted as low effeciency but really the midrange was very effecient (I would put it into the 95 db range-all the coupled drivers helped I guess). For a small speaker they were ok. Most bass at the lower octaves weren't that powerful anyway and most of the music energy falls into the 100hz range which is were they were very efficient. I think I finally added a piezo horn tweeter to sweeten the highs and like I said earlier-a good subwoofer would work wonders for the low end. No eq. would be needed if one added the sub and tweeter. The midrange wasn't as articulate and detailed though as a horn would be. I would think the current 901's would work great in a theatre setup. Bose used to market some recievers with built-in eqs for the newer series. Specs on the recievers were ok and power output in the 40wpc range. Not enough for the older series but probably ok for the newer ones.

I would assume that a preamp turned up that high (3:00 o'clock) would run the amp into clipping and the Khorn would be extremely loud at that point! I'm sure I would hear turntable hum also at that volume level on my cheapo Yamaha reciever if I still had the turntable hooked up!

The "woody" sound is likely the exagerated response in the 125hz range. I used to use an eq. to tame that range aprox. 4-6 db. I wasn't using an inductor on the woofer to limit the high end and added one (I have homemade Khorns) and that helped by lowering the effeciency of the woofer aprox. 1.5 db. Another great improvement is adding a subwoofer to reincorce the low end to balance it more with the 125hz range. This allowed me to forget the eq. I believe that either adding a sub or an eq. are the answers to your "woody" sound. It's probably next to impossible to build a bass horn without some extra response in the 125 hz range. At least every response graph I've seen they all had the extra "punch" in that range. Probably due to wood resonances and design.

If you're saying that your old Technics reciever had better bass and treble I bet that you activated the loudness control on it and the Yamaha is lacking that feature. Also, the bass turnover freq. could be different. I know on my Yamaha the bass control goes into the higher bass too much which I don't prefer to increase. I don't know why the newer models eliminated the loudness control.

Ahh, the power of the mind!

I'm just using the cheapest Yamaha HTR 5130 reciever of 4 yrs ago and it sounds just fine to me although the dolby pro logic has a lot to be desired (distortion, noise, etc.). Plenty of bass with my khorn although it needs a subwoofer too. It sounds just as good as my older Yamaha 200watt amp and Soundcraftsman preamp I had running. Can someone explain why the RXV series has better bass? Probably has the same electronics inside!

Quote "Also, the damping factor of a solid state amp is also greatly affected by the gauge of external and internal speaker wire. " If you want max damping factor, etc. one would have to throw out the coils in the crossover network. There are many feet of extemely small gauge wire in there. Two-five feet of internal wiring is nothing compared to the coil wire length.

See my post on adding a subwoofer to the khorn. A simple 12inch good xmax subwoofer should fill the bill. I think I paid $30 for mine plus $149 for the 250watt plate amp and put them into a box I had laying around. I originally built the box for an Eminence 12inch subwoofer and the foam rotted away a few yrs ago and emailed Eminence about the specs and they told me it was made for an M&K subwoofer but it was very, very easy to overload at low freq. from a 25watt amp. It just wasn't useable. I then spotted this car subwoofer on ebay (MAaudio) for $30 and it kicks. It just has an xmax of 10mm but I haven't been able to get it to bottom at 120db, etc. It probably does suffer from some compression of sound at higher volumes though. Compliments my khorns nicely and would work great for your Heresy's. I can get you the model number if you are interested.

Let's see, the coils in the crossover are what gauge? Probably very thin 20gauge or less! Wire that is beefier than the coil winding wire is useless. Fresh 16-18gauge zipcord will be just fine but if the old stuff looks good don't bother. I got a kick out of the post about 10gauge wiring!

I bought a 12inch car subwoofer for $30 on ebay and in roughly a 3.5 cu ft box tuned right it has an f3 of 27hz. It will easily blow away the khorn below 40hz. The low, low freq. just aren't there in my homebuilt khorns. I cross the subwoofer over at 40hz and power it with a 250 watt plante amp from parts express. If listening to exteme sound levels 2 subwoofers would probably be better. I probably get some compression at high levels with low bass but have never bottomed out the cheap $30 car subwoofer. No more need to boost the low end of the khorns 12db with an eq. anymore.

I always had better luck setting the tracking weight near the heaviest that the cartridge said worked well. Less distortion particularly in the inner grooves. Record wear from a heavier weight was probably negligable. I found this out with several cartridges and was fighting distortion when set at the lightest suggested tracking weight. Increased the weight and distortion went away for the most part except some pressings still had some innter distortion. My Mobile Fidelity pressing was perhaps the best for distortion free inner grooves. FYI I don't even have my turntable hooked up right now. Can't stand the pops and clicks, etc. and yes I do clean them (discwasher) before I play them.

You're dealing with a 70hz horn. You need a sub. You don't need to spend a large amt. of money if diy. Sticking it into a corner won't change the flare rate.

How many db down is the LaScala at 40hz? Probably 10-15db. It definitely needs some kind of bass reinforcement! My homebuilt khorns were always lacking in bass and had to use eq. to bring up the bottom octave to decent levels to be happy with them and finally bought a $50 Maaudio 12inch car subwoofer that fit perfectly into a 3.7 cu ft. enclosure I had-added a 250 watt parts express plate amp and can't believe the bass extension! The speaker specs out as -3db at 27hz. I cross it over at 40hz and with the LaScalla probably would want to bump that up slightly. 35hz - 40hz sounds pretty low to me but you've got to get the level up to midrange levels to enjoy that. I couldn't imagine living with a LaScala without a sub! Theoreticallly an eq. with max boost in the 30-50hz range might give acceptable results and should be your first and cheapest remedy and if that doesn't do it add a sub. Most of the music I listen to (from classical, organ, country, pop, rock, etc. all beneifits from a sub that gives the 40hz range a boost. Perhaps I just like the 40hz bump a little!

Did you see my thread a couple weeks ago on a car sub for home use! I bought an MAaudio MX121Q driver or something like that for $50 with shipping on ebay. I put it in a 3.6 cuft. box I had and used 2 3.5 inch (inside dia.) ports aprox 13.5 inches long to tune it to 27hz or so. It models out to something like f3 of 27 hz and can put out 120db at that freq. or so. Used a parts express 250watt plate amp and it sounds great. It only has an xmax of 10mm but I haven't been able to get it to bottom out! Compliments my homebuilt khorns greatly. You really have to model each speaker individually but will agree with previous post that mose car subs are designed for a smaller box and consequently higher f3. I downloaded some free box programs to model them.

I just couldn't stand it! I just wasn't happy with the low end of my homebuilt khorns and I had this 3.6 cubic ft. oak enclosure in my storage room with a rotted out Eminence 12inch subwoofer. I knew that my khorns blew away that Eminence speaker. Heck, the speaker couldn't handle 25 watt/channel amp at lower freq. I started to search for a suitable 12inch subwoofer for the enclosure and came a cross a car sub that is an MA Audio 121XQ dual 4ohm 12incher that modeled out to a 100liter enclosure. It has an f3 of 27hz and can output 120db from 30hz on up and 105db at 25hz. I found one on ebay for $50 with shipping included. I wasn't expecting a whole lot but went ahead and put it into the enclosure and wow! Couldn't get the cone to bottom out with the same old JVC 25watt/channel reciever! Finally finished the cabinet by staining and varnishing to match my khorn and bought the 250watt plate amp from parts express and hooked them up tonight. I ended up with 2 3.5 inch (inside dia.) ports aprox 13.5 inches long. This thing will rattle the windows in the other room easily! The khorn just won't compete in the under 40hz range with this budget speaker! The only problem is keeping everything from rattling in the room and the back of the speaker has a rubber cap and steel mesh grille that vibrates (only noticable when khorns are turned off). This speaker only as an xmax of 10mm but doesn't bottom (probably distorts though) and puts out way more than enough to augment the khorns. Organ music and special effect music come through great! No need to run an eq. on the khorns again! This speaker was putting out over 115db of bass at my listening position in my smallish room (13x14ft with 9 ft ceiling and couch against the back wall). I thought the khorn was suppose to have the most bass output!Anyway, I have perhaps $200 invested. Maybe I should have bought a better driver like the Dayton dvc or Shiva but I was too skeptical about spending that kind of money. I have seen these MA speakers go on ebay for around $35 a week or so ago also. A must have for the final touch. If I had to do it again (build the khorns or such) I would build something like the Heresey (or smaller high efficiency speaker capable of going down to the 70hz range) and run some subs instead of taking the time to build some khorns.

What's wrong with you dvd Dayton sub? I assume it's the 12inch model? Sealed or vented cabinet? Perhaps you just need to make a vented cab. instead of sealed? I'm in the process of putting together a cheap sub with a MA 121XQ 12inch with 10mm xmax in a 3.6ft. cab. I had sitting around and will see what it will do to accompany my khorns. Should produce 120db at 30hz with enough power but only 105 at 25hz and 95 at 20hz. Paid $50 shipped for the speaker. The Dayton DVC sub interested me but the parameters weren't right for my cabinet. This MA sub should be 28hz -3db.

One could add a box to the side that the woofer cover is on. One could also cut into the baffle "voids" and even open them up to the front and add space out front but I wonder if the small openings into the voids would act like a port instead of extra space. I haven't figured out how some of the early khorns actually opened the chamber into the upper and lower boxes. Do you have any diagrams of this?

The early style 901's that I built had very effecient midrange but one had to run 12db of boost in the bass and treble to make it sound balanced. I would imagine though that one could run them unequalized as a pa speaker and not sound too bad for voice with good efficiency. I ran mine with a 200watt/channel Yamaha power amp. The bass could be overdriven though. The small speakers just didn't allow much cone movement for good bass. One will notice my posts on eqing the Khorn replica I have too. Sure, the khorn will blow it away but the idea of the 901 was unique! Bose maketed thei own power amp with 2 pairs of 901's. I bet it sounded pretty good in it's own right! Surround sound in the early 70's! Come to think of it, there was surround sound in the 70's! If one didn't hang them from the ceiling and used the pedestal one might as well have had a cabinet that went to the floor with a subwoofer or woofer built in to help the low end. Oh, and a good tweeter wouldn't hurt either! I finally stuck on a horn piezo tweeter to help the highs.

Internally, my horn is the same as the Khorn. I saw what you were talking about it (L.E.E Catenoid) and it's totally different. I consider this a "stripped" Khorn and looks a lot smaller but actually has the same flare rate, horn throat design, etc. If you look at the Khorn tailboard you will come to the conclusion that it's really not necessary. I don't think that the waves hitting a flat panel is any better than hitting the side walls and being directed to the other wall, etc. Anyway, the Khorn and Speakerlab are compromised designs. I would venture that any gains are going to be in the flare rates in the throat, etc. and back volume chamber, not the exit points of the horn. Maybe I could design a way enlarged back chamber with ports like the La Scalla thread?

My bass bins are 39" high and the side horns are about 3.5inches at the back to the sidewall and in the front they are about 5.5 inches from the sidewall. My front panel is 24inches across. Speakerlab said to move them 8inches from the back corner and I have found that is a good compromise. If I move them closer to the wall I do pick up some lower bass but sacrifice some topend, etc. I believe the dimensions are the same as the Klipschorn but mine doesn't have the side panels, tailboard, and topplate. I did notice that the Klipschorn top board is open to the midrange, tweeter housing for some reason at least on some models. I can easily move mine by myself for a short distance, they don't look so big in the room either. There appears to be a lot of needless wood on the Klipschorn that won't help sound but does give it a different look.