Tweeters for 1k hz XO?

[Digeridoo]

Hi -- Looking for recomendations/experiences w/ tweeters that don't mind being xo'd low, such as 1K (or even 900) hz. I'm thinking dome but open to other ideas of course; low efficiency OK too, for the moment.

I'm aware of the many trade-offs and likely limits of physics here, so before I go off and fry my tweeter collection in pursuit of a whacked idea I thought I'dpick the collective grey matter of the group.

FYI, I'd happily go into more of what I'm thinking, but in the interests of focus I'd like to focus on the specific question at hand for the moment and minimize the amount of time taken up from all of the things we should be doing instead
J

[Cal Weldon]

Look for a tweeter with an Fs of about 500Hz. That will allow for an XO of about 1K. Just remember you are likely to need a steep slope XO as the power rating goes down when you lower the XO point.

[ScottG]

two other suggestions (in addition to the steep crossover)..

1. you can "horn" load the lower end response (..but try and match directivity at crossover with midbass driver). A waveguide is typically suggested here.

2. you can also use multiple tweeters as long as the spacing between the drivers is fairly small (to minimize the effects of combing).

Addtionally - you could use a "fullrange" driver here instead, particularly one thats about 2 inches. Note that to do this however will result in greater sound pressure loss off-axis.

There are 2 inch drivers from
Aurasound
Bandor
HiVi Research (Swans)
Jordan
Tangband

(..the "premium" drivers in this listing are from Bandor and Jordan.)

There are also a few smaller mid-tweeters (around an inch and a half) that could also be considered (perhaps utilizing a super tweeter to support them):
Accuton
Aurasound
LPG
etc.

For the tweeters look at Zaph's tweeter "mishmash" tested group:

http://www.zaphaudio.com/tweetermishmash/

When you look at some of the "flat'er" tweeters to 1 kHz, also look at the harmonic distortion levels at these lower freq.s. In addition look at the manufacuter's spec sheets for information on x-max. The CSD also suggests subjective clarity.

My "pick" would prob. be the Vifa DX25 despite having higher levels of 2nd order distortion at lower freq.s and a slight dip at higher freq.s. The 2nd order distortion is consant in sound - 3rd (+) is dissonant, and it has pretty low distortion for 3rd (+) at these lower freq.s. Of course it also has a VERY extended passband.


Remember however that these measurements were effectivly taken with an "infinite" baffle. IF your intended baffle isn't very wide then you'll likely see some sound pressure loss at lower freq.s.

For more information on baffle "losses" have some fun modeling with the Edge at a *1 meter* distance:

http://www.tolvan.com/edge/

[keyser]

Conventional tweeters will have a very hard time coping with full power signals at 1 kHz. Some 1" domes can do pretty amazing thing things these days, but a crossover this low is asking for troubles.
As Scott already pointed out, you'll need a bigger unit. The B&G neo8 may be your ticket.

[Jonasz]

Maybe you can try the Dayton RS52 (2" dome) crossed at 800-900hz and if you think it's necessary use a supertweeter for the last octave. It will easily cope with the low crossover but you will have to notch the peak around 13khz for optimum performance.

http://www.partsexpress.com/pe/pshow...number=285-020

[sreten]

http://www.madisound.com/cgi-bin/ind...16010&pid=1810

/sreten.

[stuck.wilson]

to go that low, you could go with a 1.75-2" comp. driver and a horn.. klipsch did it lots of times-- i use an altec 414 and a BMS 4055nd on a 90x40 horn. my crossover is 1100, but first order.

but horn crossovers are tricky-- not impossible.. to get mine just so took 6 months... there's not a lot of good resources on dealing with horn loading that you can find on the 'net- and getting your compensation network (dealing with the natural rolloff of any horn after around 3k) can be a bitch.. but in the end, it can be pretty rewarding!

d.

[Digeridoo]

Many thanks for all of the thoughtful replies -- some very helpful thinking here, including the lateral thinking -- much appreciated.
If you hear a pop! followed by a burning smell, you know what I've been up to....