Peerless HDT 100 tweeter for Karlson party speaker project

[bikehorn]

I'm presently gathering ideas for a pair of K15s i will be building in a few months. I found a woofer i wanted to use, however, an appropriate HF solution appears to be the more difficult aspect of the design. I thought up a bunch of off-the-wall schemes to get full-range from a Karlson, including a built-in line array of 8 2" tang band drivers but eventually settled down and got real. i decided that since the classic Karlson is built around a point source(i.e coaxial or triaxial) i wanted some similar solution. unfortunately no low-Qts 15" coaxial woofers exist which are also easily available and cheap. the coax idea would have been scrapped right there, and as a matter of fact it was until i looked at some pictures of vintage coaxials...with a regular tweeter suspended in front of the woofer as opposed to coming from the back of the speaker. i also wanted to keep it two-way. up until that point i had planned on using a compression driver mounted in a horn lens or a Karlson tube waveguide.

mounting a smallish tweeter coaxially over the woof seemed like a good solution but i couldn't find any tweeters that could match the 99 dB sensitivity of the woofer, best i could do was about 93 dB or so until i came across the Peerless HDT 100 on Madisound. Peerless' own website doesn't list it, although i know it did in the past...not to mention Tymphany seems to suffer from clunky web design.

http://www.madisound.com/pdf/peerless/811647.pdf

this tweeter claims 99 dB sensitivity from a rigid horn loaded dome, and high power handling to boot! and it's pretty cheap too. everything looks good, going by the graph, some stuff i've read and my own lack of experience, i was thinking of crossing at 2500ish hz at 24 dB/octave because the woofer runs out of gas at 4000.

my design goals for this speaker are few, and not too too rigid either.

1) high output through high sensitivity and high power handling. can give up some sensitivity if need be.
2) i'm in university and i plan to be throwing some major keg parties. need lots of midbass punch and slam as a 15" Karlson tends to roll off around 50 hz.
3) i don't, and won't own any high-end audio equipment for a long, long time. the power source of choice is probably going to be a vintage Technics or Sansui reciever of some sort packing ~70 wpc. this is about as good as the source is going to get...potential upgrade to gainclone type stuff later, but that's far off. an EQ is not out of the question
4) wide dispersion, mostly will be handled by karlson's aperture
5) these are not going to be speakers for parking in a listening room and listening to jazz on a pair of 3 watt SET amps while experimenting with toe-in and finding a sweet spot. I have nothing against any of that, but i have to be realistic...i just don't have any illusions of doing that myself in the forseeable future. aside from myself and a friend of mine, i'm really not surrounded by audiophiles so nobody will know what a transient is, the point of coaxially mounting a tweeter, what room acoustics are, the reason a Karlson looks funny, or really anything other than the fact that it will sound different/better than their "gold standard"...Bose.
6) i dabble in DJing as a hobby. the speakers will have a pair of 1/4" jacks on the back so that in a pinch, i could pull these speakers out of reserve for DJing use, although for the sake of the finish i'm going ot put on them, that's not going to happen very often. i know it's no problem for the woofer because it's a pro sound type with a heavy duty surround and beefy voice coil. i hope the tweeter is able to handle occasional DJ use...seems like it should if it's rated for high SPL and power handling. plus a similar dome mid by Peerless is used in a bass cabinet design by Len Moskowitz.

has anyone had any experience with this tweeter? thanks.

[moray james]

Why not have a look at the motorola piezo compression drivers (they are very small) and fit one to a Karlson tube (Freddy has all the data). You can lift your woofer's dust cap and mount the whole assembly directly to the woofers pole piece. About as coaxial as it gets. Regards moray james.

[bikehorn]

but....piezo? won't that sound terrible?

[moray james]

That depends on which unit you choose and how you use them. Plenty do sound bad but if used properly Piezo tweeters can sound wonderful. Like I said Freddyi has most all the info you will need. Regards Moray James.

[bikehorn]

thanks, i'll mention it on the K forum. the only concern i have is that the sensitivity will be mismatched...the ones on parts express' site are all down in the low 90's. there's one exception, but it's 4" in diameter so i doubt it would fit where the dust cap once did.

what of the original plan, the Peerless dome? want to keep my options open and sensitivities similar.

[moray james]

Your idea is a good enough one. Perhaps you should go with that one and see what you can make of it. Don't forget the the k-tube will give you some gain. You could even try the k-tube on the Peerless just to see what happens. What you do is up to you. The more that you try the more you will figure out. Regards Moray James.

[moray james]

Here is a very small tweeter that has high efficiency and might fit nicely inside of your voicecoil fitted with a k-tube. Regards moray James. http://www.leson.com.br/tlm1_180w.htm