Help - Klipsch KL-650-THX clone project

[Marzen]

Looking for driver suggestions for a DIY version of the Klipsch KL-650-THX LCR speakers.



Thanks,
Ward

[timber_mg]

The compression driver is likely nothing too spectacular. Perhaps something out of the eminence catalog for the MB drivers seeing that they have a high F3? I would guess they don't have much BSC on the units (prob best soffit mounted)

The horn is probably hard to source. If you have the luxury of EQ you could even try a waveguide loaded conventional tweeter. Celestion do a nice 8" for that kind of system. One thing is for sure...amongst the hi-fi usual suspects you're looking for a fairly unusual set of T/S.

[Marzen]

Thanks. I think I'll stick with a threaded compression tweeter and horn vs modding a std dome tweet. I'll look for some Eminence drivers although I haven't had any success at finding online measurements for compression drivers ala Zaph's website. His java page for the 6.5" comparison is a real help.
And yes, these would be wall mounted behind a pj screen if it pans out.

Where's a good site to find a selection of horns?

-Ward

[ThomasW]

Ward,

Have you looked at the B&C compression drivers and wave guides Jon and other's are using?

[Evil Twin]

Check out DDS at Assitance Audio, with BMS drivers; also 18Sound and Beyma.

[Marzen]

Ward,
Have you looked at the B&C compression drivers and wave guides Jon and other's are using?

Only in passing, & that was some time ago. I'd prefer to stay within the constraints of the Klipsch design as I'm really curious to see what this sounds like; what with a shallow tractrix horn & dual mid woofers off to the side. More curiosity than any real desire.

Check out DDS at Assitance Audio, with BMS drivers; also 18Sound and Beyma.

Ah, right on the money. H & V polar plots as well...sweet!
Hey, I even found some THX specs for room decay, etc after surfing a bit. This hobby is an OCD paradise :T

Thanks all,
-Ward

[timber_mg]

You will probably not get that horn, lest you want to actually copy it off the real thing. I would look at the currently popular waveguides as an alternative, with the DDS probably closer to what you want, however something asymmetrical like the 18SOund XT1086 would better match the dispersion of the two woofers. You could even see what happens using a cheap compression driver initially and then go for something like a BMS/18SOund/B&C or other quality 1" driver. The Eminence Alpha 6 looks quite usable (prob cross around 1k5) and probably doesn't cost too much.

Personally I'd just do a 12" 2-way and be done with it.

[Marzen]

Thanks for the suggestions, I'll look those up.
I want to learn to use SoundEasy's horn modeling feature.
I have a pair of 12" two way Peavey speakers.
-Ward

[Tim]

The review I saw of the speakers shows that they have 92dB sensitivity and roll off at about 75Hz. If you want some shielded aluminum cones I would probably look at the Dayton Reference series for about $30 each.

For 1" compression drivers you have several choices and they are all similarly priced. Of the ones I have heard and measured I would recommend the following: BMS 4540ND $95, BMS 4550 $110, BMS 4552ND $145, and B&C DE250 $128. The B&C DE500 $155 also comes recommended but I haven't personally heard this model. Of these the 4540, 4552 and DE500 all have compact neodymium motors, but I'm not sure if that makes them shielded or not, I would guess that they are not shielded based on the location of the magnets.

For horns I would 2nd the recommendation of the 18Sound XT1086 $45. Based on measurments and from experience the DDS CFD 1-70 also sounds good.

The initial investment would be about $200 for the XT1086, 4540nd, and 2 Dayton RS180's. Budget an additional $50 or so for wood and crossover parts, maybe more if you do a 2.5-way.
Tim

[Marzen]

The review I saw of the speakers shows that they have 92dB sensitivity and roll off at about 75Hz. If you want some shielded aluminum cones I would probably look at the Dayton Reference series for about $30 each.

The only review I've read so far was over at Audioholics . They gave it a good rating; which really whet my appetite after having put my Peavey SP2 horn pa's up front for a sample run. Reference grade? Hardly. But they were very intelligible, extremely dynamic and really give you a good pounding during a movie. Now I wanna take a crack at making my own.

For 1" compression drivers you have several choices and they are all similarly priced. Of the ones I have heard and measured I would recommend the following: BMS 4540ND $95, BMS 4550 $110, BMS 4552ND $145, and B&C DE250 $128. The B&C DE500 $155 also comes recommended but I haven't personally heard this model. Of these the 4540, 4552 and DE500 all have compact neodymium motors, but I'm not sure if that makes them shielded or not, I would guess that they are not shielded based on the location of the magnets.

Could I talk you into sharing some of those files?

For horns I would 2nd the recommendation of the 18Sound XT1086 $45. Based on measurments and from experience the DDS CFD 1-70 also sounds good.

Thanks for the recommendations; both 1st and 2nd. I'm not very knowledgeable with horn technology so this will hopefully get me in the mix.

The initial investment would be about $200 for the XT1086, 4540nd, and 2 Dayton RS180's. Budget an additional $50 or so for wood and crossover parts, maybe more if you do a 2.5-way.
Tim

I won't need shielded drivers as I run a front projector. I already have RS180's but was really thinking about max spl. Low distortion isn't topping my design list on this one - max dB's are, what with a 28' x 40' room. I think the 180's might be excursion limited and I'd like to get away from the RS line for a bit. I have quite a few now, in fact it's pretty much all I have from tweets to subs.
I have a short list of potential ~7" drivers I've culled from Jon & Zaph's test results. The horn tweeter will probably take some time to really figure out the hows and whys. I was kinda hoping someone could just point out a suitable compression tweeter that would be very similar to the Klipsch model, if not a flat out DIY version of a potential OEM driver. I should probably just write Klipsch and see what a replacement tweet and horn would cost, but that seems a bit like fudging & I'm in no immediate hurry with another current project in the final measure and tweak stage (which is not as much fun as I thought it would be... :Z ).
Regards,
-Ward

[timber_mg]

They use a cheap 1" diaphragm driver which is potentially something not too expensive.
Just use the Eminence Alpha 6 if you want something with a bit of thwack that's not horrible sounding and mate it up to the XT. Looking at the flare it doesn't seem very tractrix at all, more likely conical.

Where was it measured 92dB? That is waay under spec. If you want a cheap comp that fares alright but needs to be crossed say 2kHz min and has a bit of a dip around 13kHz unmodified I would look at the P.Audio PA-D25 or the 18Sound driver they usually put on the back of the XT-120 horn, but DON'T use the XT120 horn if you want a hint.

[timber_mg]

Audioholics use a 120dB! scale on the FR plot on the KL-650...but it seems it seems to be an eye-ball around 103.5-104dB sensitive which is nothing to be scoffed at.

[Tim]

104dB from 2 6.5" midbass drivers that aren't horn loaded? They must be taking measurements at 2.54 inches from the speaker. I got my 92dB rating from the review below.

Here is the link to the review from Home Theater magazine

http://www.klipsch.com/media/news-center/reviews-press-pdfs/home-theater-thx-ultra2.pdf

If you want bass to 60-70Hz the most you are going to get is 90-93dB with 6.5" woofers, because you have to consider baffle step loss, unless you are going to soffit mount them. If you go with some pro 6.5in dedicated midranges you get higher efficiency but you would have to crossover closer to 250-350Hz. If you are thinking that you want an honest 95dB at 75Hz you are going to be looking at a pair of 8" woofers minimum, or a single 10-12" driver. Look at the response on Zaph's waveguide TMM for an example of what you can get with some light weight 6.5" paper cones. I read somewhere that the Klipsch also are a 2.5 way design.

In addition to the Alpha 6A here is an example of another Eminence midbass that has decent efficiency, but less xmax than the Dayton, so it would have less displacement limited maximum output. http://www.partsexpress.com/pe/pshow...Number=290-540
If you want really high output levels from a 6.5" I would look at the Usher 8945A, you will just need plenty of power to drive it,

http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=296-600

that is currenlty on sale for $75 each, although it is back ordered. It has xmax of 10mm from Klippel testing.
You can get higher efficiency with something like this B&C

http://www.partsexpress.com/pe/pshowdetl.cfm?Partnumber=294-651

but it is a dedicated midrange and will not make it down to 80Hz for the subwoofer crossover without losing all of its efficiency.
Tim

[Marzen]

Thanks Tim for some more good reading for this Saturday. I'm going to move my screen and pj this weekend to take advantage of the long wall so I can move my speakers out and just about meet the results of the Caradas placement calculator. I did this once before when I initially finished the Modula MTM's. Using this placement even my PA speakers threw a pretty decent image, the MTM's sounded great.
I stopped at BB on the way home and raided their BluRay section. I want to have some of the guys over and use the horn pa's for mains and see what their response is since they've all heard the MTM's before. 'Apples & oranges' comparisons aside, I think the sheer sonic impact will win out over finesse and accuracy; at least for movies.
I'll be back after the weekend with some more (intelligent?) questions after I read up on the above as well as some THX theater specs.
Thanks again,
-Ward

[timber_mg]

Less 10 dB...whoops (been measuring too many compression driver horns lately that I unlearn sensitivities below 100)

[timber_mg]

And I would doubt that Klipsch would make it a 2.5 way. Tee whole idea is to get greater vertical directivity and the directivity would also match much better that way to the horn than with a .5 filter in there. 1.4kHz cross would make sense and is easily achieved with most 34/44mm diaphragm drivers but for the lower sensitivities a 1" diaphragm might well do the trick regarding output.

[Marzen]

Personally I'd just do a 12" 2-way and be done with it.

I would have to agree. I moved the fp screen to the long wall, spread the speakers out to 12ft c2c - waaay better imaging than the short wall. We watched Crank & Kingdom of Heaven & some HD basketball while A/B'ing between the Peavey (15" + horn) and the Modula MTM's (6.5" mid woofers).
Trying both full range & 80hz xo it was unanimous in favor of the Peavey's running full range.
All of which has me leaning towards something more like the 18sound 12" 2 Way Kit. This uses the XT1086 horn (80° H x 60° V) compared to the Peavey SP2 which lists:
"Radiation angle measured at -6dB point of polar response:
90° horizontal by 40° vertical.
The vertical main polar lobe is
angled down 10° with respect to
straight ahead being +10, -30°"
I didn't realize there was a 10° downward tilt until now, I'll have to raise them up a bit and see how they sound.

[timber_mg]

I can highly recommend an OS waveguide. Works well with most compression drivers.

The B&C DE-25 is a perennial favourite and the BMS 4550/52ND are other good options. Perhaps I should start making fiber-glass copies of my OS profiles. The 12W700 looks like a good value (seems better behaved around crossover). For hifi use cross the 12 closer to 1k2-1k4.

[looneybomber]

Did anything ever happen with this idea? I'm looking to build a 5.1 system that will not only sound phenominal, but also be capable of fairly high SPL numbers. I was looking at the 3way Dayton RS TMWW and WT/MW mains but see that it has a low sensitivity in the mid 80's. Horns will likely be the route I'll have to take.

[Marzen]

I ended up putting this on the back burner for now. I moved my DIY Dayton speakers upstairs and am using two way pro horn speakers for my front three.
If you're on the fence regarding horns I'd suggest picking up three at your local music store for a weekend demo.
They are certainly loud, FULL range, and quite dynamic. I'm tempted to rent some 3 ways and see how they sound in comparison.
If you find anything Looney, send me a link. I'd like to get back on this after the summer.
-Ward