homemade

What about upgrading the small gauge wire used in the coil? I'm guessing there is something like 50-100ft of 18-20 gauge wiring in there?

Well, how does Klipsch get efficiency's in the high 90's with their Cornwall? I believe the woofer is rated at 96.5db or so but it's a 4ohm speaker so will sound louder with same voltage input. I'm running an 8ohm version in my homemade Khorn and running it with a 99.5db efficiency midrange and it mates pretty close although there is a bump in the 125hz range. So how does Cerwin Vega do it? Are they running a hotter midrange and relying on a higher Q woofer setup that gives a bass boost in the 60hz range and consequently a dip in the upper bass that people won't miss? That's my guess on the Cornwall vs say a La Scala. The La Scala will have perhaps a 5-8db boost in the 125hz range over the Cornwall and less deeper bass-hence a big difference in the way the bass sounds.

I have a Panasonic F87 5 disc dvd player that as built-in dts and prologic 2 decoders. The prologic decoder is much, much better than my Yamaha's older pro logic model. My Yamaha HTR5130 has 6channel input (not built-in dts decoder) and can vary the amt. of subwoofer output but the Panasonic F87 apparently doesn't output anything on the subwoofer channel when in the prologic mode (when playing back surround encoded cd's) although it works great with dvd's. I would assume I would have to set my main speakers as small (Khorn knockoffs) to get output from the subwoofer. Perhaps a better way to hook up the subwoofer is to not use the subwoofer outputs at all but use the high level speaker inputs into the subwoofer amp. This way one is guaranteed output from the sub.

I used to run a 10band eq and than bought a 15band eq and haven't used it lately. Used to reduce the 125hz signal on my homebuilt khorns by 6db and boosted the 30hz band around 10db. Finally built a sub for the khorns and use the sub adjustments to suit my taste and run the rest of the khorn flat. Sure, I get a little boost in the 125hz range but with the sub I boost the lowest octave accordingly. I love the extra punch in the lowest octave and don't notice the 125hz bump anymore. Treble is just fine flat. Without the sub, I would have to run an eq. Just couldn't stand the "thin" sound without the extra lower octave boost.

Where's the review on these badboys? I want to know about the woofer control pot also. Thanks.

My Speakerlab plans talk about a control to adjust the amount of bass response. Is it just a simple L-Pad or more to it? How do they sound compared to the real deal? They look nice to me.

I have the same literature that Klipsch put out. I don't have it in front of me and could hardly read the cycles part of the scale. The top graph is the Khorn and bottom is the La Scala? Doesn't the top graph show -10db dip at 30hz? The Khorn is strong to 40hz (but substantially lower than the 125-250hz band) but response below that falls off like a cliff. One thing I did notice on my speakers is that I was running the woofer straight without any coil to kill the top end and found out that a coil reduces the efficiency of the woofer aprox 1.5db and it sounded much more balanced in my system. The coil probably started to cut out the higher midbass around 250hz and gave a more balanced system but it still sounded "thin" without either a subwoofer or max eq. boost on the lowest octave.

There aint no way a khorn is going to be flat to 30hz. Mine (mine are homemade but same internal dimensions and woofer a good match to khorn) are perhaps 12-15db down at 30hz. A khorn has horn response down to 40-45 at most and below that is just a sealed box with fairly high resonant freq. plus a hump in the 125hz range. A room would have to be designed to actenuate the lowest octave significantly. I've had mine in 2 different sized rooms (not even close dimensions) and the freq. response was about the same. If you listen to mostly symphony without a bass drum, no synth. music or modern music, maybe you can be satisfied without a sub. Organ and home theatre need lower, flatter bass and most other music even pop 40 on radio sounds better. A speaker that is flat to 35hz without any hump higher up would probably satisify most of my music but one that is 12db down at 40 just doesn't cut it.

What a steal! Let us know how you think they sond compared to the real deal.

Picture 3 of my top enclosure with the grillcloth removed.

Picture 2

Here's some crappy pictures I just took using my camcorder in very dim light.

These were the speakerlab plans that I used to build my khorns replicas. I didn't mount the audax and t-35 in front of the enclosure but built separate boxes on top to allow rotating them slightly, etc. One thing I never did find about was the ability to adjust the bass response via the crossover with a potentiometer. By doing away with the tailboard and added sides of the khorn the speaker fills the corner less. I have experimented with sealing the top to the corner and adding a tailboard but didn't really notice any response difference and concluded the khorn had a lot of unnecessary appendages. Perhaps PWK never thought about the savings from this move. My Audax foam surrounds are doing just fine and they are probably about 20 yrs old. but I don't abuse them either with weather extremes, humidity, etc. that a professional PA system would be subjected to. One can move the speakers further toward the corner, away from the corner, etc. and evaluate the response but to measuring the low end, not much happens but differences may appear in the 2-400hz range. If I had to do it again, I would build some LaScalas instead and run a subwoofer. I really like the looks of the LaScala but they would take up more space than the "mini" khorns I have.

One of my favorite LP's (from my LP days) was a Moody Blues album that featured a real low freq. at the end of the song(probably was only in the 35hz range thogh). I took that record over to the Klipsch dealer and had him play it through some LaScalas and didn't hear non of the low bass at all. Very dissappointed. The salesman said that by looking at he grooves he could tell that they weren't really that low or loud! I'll have to dig out that album and record it onto a cd and find out how low it actually was. Can't even remember the song since I haven't listened to it in years. The song came out in the early 70's. There was a lot of music in the 60's that had a low freq. overtone. How about Simon and Gargunkels Bridge over Troubled water (or was it boxer) as an example. Probably lows in the 3-40's.

I've said it many times on this forum but my homebuilt khorns benefit greatly from a 12inch subwoofer. The khorn is way down at 35hz and needs some help there. My subwoofer models at 27hz at f3. I do believe though that if a speaker is flat to the 35-40hz range the bass will be pretty good and deep and if I had a Cornwall it might be sufficient for most 2 channel music but you can't have a horn speaker that is -10db at 40hz to not sound bass shy!! I was getting by with eq.ing it 12db at 30hz or so but one day ran across this 12inch subwoofer (car model) on ebay for cheap and I had the cabinet already so I bit. Purchased a 250watt plate amp and couldn't be happier. It doesn't really take much for the 12inch to keep up with the khorns at a little less than ear splitting levels. I probably have it overboosted at 40hz but that's the way I like it. FM radio even sounds better with it. Organ music-no contest.

Your new cornerhorn speaker looks like my Speakerlab cornerhorns. Same internal dimensions of a khorn but without the unnecessary appendages. What I can't figure out is the woofer cutout in the "beginning" picture. Why the big circle above the throat? Nice job.

Quote: Do you have the T/S parameters for the driver? Or at least the make and model number? Unless it's got extreme power handling and excursion capabilities with powerful motors, I have a hard time believing a car sub can keep up with khorns. I know the klipsch ultra 2 subwoofers implement 12" drivers, but their motors are very powerful (in fact, same motor as the RSW-15) and they are being powered by a very nice amp tweaked to enhance the sound. For the sake of mdbrien (the starter of the thread) I have to put up a DIY syndrome flag (where things sound different because we built it ourselves). Yes, the specs on the carsubwoofer is: Manufacturer: MA Audio Model: MA121XQ Fo: 29.58 QMS: 2.56 QES: .58 QTS: .47 VAS: 99.98 liters SPL: 88.36db\watt\meter XMAX: 10mm I speced it out in my roughtly 3.5cu ft enclosure and the f3 is roughly 27hz. Running a 250watt plate amp into 4ohms (one voice coil on the subwoofer) I haven't been able to bottom out the subwoofer but I'm sure there is compression at higher power levels. I wouldn't say that it would keep up with a khorn at full volume but at less than ear splitting levels it's just fine. I think I paid $30 for the subwoofer on ebay and already had the cabinet. I previously used an Eminence 12inch subwoofer (15yrs ago) that was oem for M&K but that subwoofer was a joke. 25 watts at 20hz would bottom the subwoofer out! I'm sure a 12inch subwoofer with an xmax of 14-20 would outperform my elcheapo but I'm happily surprised at what it can do.

I would say that most components with loudness comp. circuits are always variable. Even cheap car stereos that had a loudness control were variable-just not adjustable. Most of them were calibrated to cancel out any bass and treble boost past 1/2 volume or so. If I remember correctly, look at a Radio Shack catalog and many volume controls have a loudness tap built onto them.

I can tell you that a simple 12inch subwoofer in a proper ported enclosure will beat the pants off of a pair of khorns in the 20-35hz range. 40hz probably would be low enough for most music if it was flat to that frequency which a khorn isn't. At least mine needed a 12db boost at 32hz and cut of 4-6db at 125hz to smooth out the bass reasonably. Finally built the sub out of a cheap carsubwoofer of proper specs to balance things out nicely without the need of an eq.

I'll bet the boomy bass is actually too much bass in the 125hz range. By adding a subwoofer to my system it has become more balanced and I notice the effect less. One could use an eq. to reduce that part of the sound spectrum too. 4-6db cut in the 125hz band will do wonders. Too many design compromises and resonances in the speaker and perhaps room to keep that band tamed down.

That 8m driver looks great for a midrange. It could even do duty as a center channel or front side channels in a home theatre setup! I thought my Audax PRM17's were the hot ticket but these look even better. Try them without a horn first and let us know how they sound compared to the K400 horn setup.

I have my sub hooked up the sub output of my Yamaha too but there's one catch with my system. My Panasonic F87 dvd changer has a much better prologic II decoder but apparently it won't send any bass to the reciever when the main speakers on set on large (I'm running homemade khorns). When playing back a dolby digital dvd it works fine. The prologic decoder built into the Yamaha reciever (model HTR-5130) has a terrible decoder. It creates noise and distortion and the Panasonic decoder exhibits non of these characteristics. I bought the Pana because of the built-in dvd decoders which my Yamaha is lacking. Otherwise my Yamaha works great-no complaints.

My el Cheapo 12inch carsub in a ported 3.5 box performs nicely with my homebuilt khorns. Plenty of output at ear splitting levels with a 250 watt plate amp. Could the cheapo sub keep up with 2-300watt input to my khorns-no way but neither could my ears. In a modest size room it's more than enough. A good 12inch sub should be plenty for the Heresy.

Here's a freq. plot with my homemade khorns with the Audax 6.5inch midrange, T-35 EV treble horn and Eminence 15inch woofer (8 ohm) and 12inch subwoofer. This freq. response is with 10band 1 octave noise and Radio Shack meter (uncalibrated). 32.5hz +1db 63hz +5db 125hz +8db 250 +3db 500 -1db 1k 0db 2k -1db 4k +1db 8k +3db 16k -8db As you can see, the midrange has a very flat response (from 500hz to 4k). The peak in the 125hz range is part speaker and part room (I had the meter sitting on an arm of a loveseat that was against the back wall). The midrange could stand to have a couple more db output but it might sound too bright.

I have an Audax PRM17 6.5inch (model number something like this) without the horn. You will probably find a less "horn" sound by eliminating the horn altogther. These run about 99.6 db efficient and if you get a 4ohm version you would be in the ballpark efficiency wise. I cross mine over at 400hz with a 12db crossover. Have run it with 200 watt amps without any problems but don't expect 120db for extended periods either.