I think we're pretty much on the same page. When I do a horn or waveguide, I basically give myself four options:
- Option one : Use a small compression driver, and cover four octaves from 1500hz to 24khz. BMS 4540ND and Celestion CDX1-1425 can do this.
- Option two: Use a large compression driver, and cover four octaves from 1000hz to 16000hz.
- Option three: Bite the bullet and spend two thousand bucks on compression drivers, and cover five octaves, from 500hz to 16khz, with a TAD
Basically my point is that I see a lot of posts here (and also on the car audio forums) where people are trying to eke out five octaves with compression drivers that cost $150. It sounds like a viable goal, but I've never seen it done in the real world, at least not without using a compression driver with a MSRP of $1000
Of course, I should listen to my own advice, and stop trying to do it myself lol (I've tried to pull off this hat trick at least a dozen times, with various horns, waveguides, and compression drivers.)
Great points!! Although I would recommend not running the CDX-1425 below 2KHz, if 1500Hz is needed then use the CDX-1745 instead its a better CD for almost the same cost. There will still be some people that also think the TAD TD-4001 isnt good enough above 10KHz, hence they add supertweeters. Im not one of those people and happy not to spend even more $$$
I have the TAD TD-2001 too and it can go low but not < 500Hz. I need to see what it could do in the SEOS-18 (If I ever get my hands on one).
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There will still be some people that also think the TAD TD-4001 isnt good enough above 10KHz, hence they add supertweeters. Im not one of those people and happy not to spend even more $$$
I have the TAD TD-2001 too and it can go low but not < 500Hz. I need to see what it could do in the SEOS-18 (If I ever get my hands on one).
I am running TD-4001 into Iwata 300 and yes they extend up to 18kHz but somehow those hi freqs may sound odds with some music and OK with other. I switched in/out a tweeter by fostex and I found that on certain occasions/records it was better to cut the 4001 at 5k and let the tweeter take over from there. I am in love with 4001 but I will be using a 2001 to cover the top end from 3-4k on a small 1k JMLC horn.
I have thought about that! There was a sweet looking but very small waveguide in the group buy pictures. I have also thought about a waveguide loaded ribbon recently. See discussions in the geddes waveguide thread about some waveguide loaded ribbons that exist now at madisound.
Of course my horn choices are only for high end home theater. All my critical music listening still comes from my ribbon choices or quality headphones.
Of course my horn choices are only for high end home theater. All my critical music listening still comes from my ribbon choices or quality headphones.
The JBL 2445 does 400 Hz quite easily. I'm running it on a large paper mache horn and it covers 400 Hz to 10 kHz with +-5db. It sounds drop-dead gorgeous too! Effortless, smooth, natural!
http://www.diyaudio.com/forums/multi-way/190326-building-johns-paper-mache-horns.html
http://www.diyaudio.com/forums/multi-way/190326-building-johns-paper-mache-horns.html
I didn't think the JBL 2445 sounded as good as the BMS 4590 or TAD TD-4001 in my tests. It definitely does 400Hz but it drops off drastically up high compared to the other two 2" CDs I have. Its definitely a popular CD with JBL fans and I read comments all the time about their performance but > 8KHz is where they fall behind IMO
Heck, I wish it did sound great considering 2 of them cost me $200 while my BMS and TAD 2" choices each cost > $1K and > $2K per pair.
I still want to get some Wavelet analysis done with all 3 CD models.
Heck, I wish it did sound great considering 2 of them cost me $200 while my BMS and TAD 2" choices each cost > $1K and > $2K per pair.
I still want to get some Wavelet analysis done with all 3 CD models.
Well, extension is not that big of a deal considering any 2" driver is pretty much beaming by the time it hits 8k. If your horn is going to start at 400 Hz, there is no way it can maintain directivity up high. In my opinion, the final choice should be based on how well it can do the 400 Hz - 8 kHz range.
I heard a TAD 1" CD on a similar horn and the JBL 2" was beating the pants off the TAD driver. But that is understandable probably, given the larger size of the JBL.
I heard a TAD 1" CD on a similar horn and the JBL 2" was beating the pants off the TAD driver. But that is understandable probably, given the larger size of the JBL.
I would not give up on the JBL drivers, especially if price is an issue.
The 2446 is a step up from the 2445 (not necessarily a large step). It has a re-designed phase plug and diaphragm and can reach higher in freq.
The JBL 2450 is even better but it is quite expensive, but so are the TAD drivers. You would be shocked by the cost of replacement TAD diaphragms.
If you go for a used JBL 2446 (a 2 inch throat), make sure the diaphragms are OEM for that particular model, or else you will not get all the benefits. There are many of these on eBay and Craigslist.
There is also the isue of how important is a two-way configuration. Going three-way to get that top octave or so, may not be a bad alternative and it opens up many other alternatives.
The 2446 is a step up from the 2445 (not necessarily a large step). It has a re-designed phase plug and diaphragm and can reach higher in freq.
The JBL 2450 is even better but it is quite expensive, but so are the TAD drivers. You would be shocked by the cost of replacement TAD diaphragms.
If you go for a used JBL 2446 (a 2 inch throat), make sure the diaphragms are OEM for that particular model, or else you will not get all the benefits. There are many of these on eBay and Craigslist.
There is also the isue of how important is a two-way configuration. Going three-way to get that top octave or so, may not be a bad alternative and it opens up many other alternatives.
I just disassembled the ribbon that I waveguide loaded last year, I'll post some pics of why I think it worked. Pics of the guts should help explain it.
Yeah, Replacement cost is $500 or more, I have checked out the sources. I have been reading about the JBL diaphragm upgrades that exist online too. Never had much luck on Craigslist but I search ebay weekly for deals.
Once Im done with the 2-way larger horn design I will consider a 3-way and figure away to blend a very small horn/CD into the design (Not easily done without looking ugly). Remember though the BMS 4590 is a coax design so it has the Full 400Hz to 20KHz performance package in it. Im just not sure yet it matches the TAD but Im still figuring things out.
Yummy looking Mummies
They look great! Mine are white - a bit more conservative, if you will...Yummy looking Mummies
How about a review?
How about a review?
rajacat,
I posted a sort-of review of my Mummies on this thread some pages ago, reflecting my early and immediate reactions. I've since upgraded my D/A-converter and made other subtle changes to the power cabling as well as adding a more resolutely configured star-grounding, and coupled with the time to "mature" impressions I believe a follow-up review could be mandated
Perhaps my recent Audiogon impressions will enlighten a bit:AudiogoN Forums: Auto-Tech speakers
A distinction must be made between my pair of Mummies and the ones illustrated above(in Mercedes silver), apart from the coloring; mine exhibit the Polish STX units, both the compression driver and bass unit, whereas the silver Mummies above feature a BMS compression driver(4524) and a Beyma(12BR70) bass unit. Sensitivity ratings are 98dB and ~94dB respectively, with the latter(BMS/Beyma) said to sport sweeter highs and slightly more extended lows(the mids not yet outlined). I'm vaguely considering a change to the BMS/Beyma Mummies, but this is still in the stages of thinking-it-through in that I have no easy way (other than going to Poland...) to audition them before purchase.
As is I'm very appreciative of my Mummy's outright honesty and sheer level of information. Theirs are not the gaudy or flamboyant sonic imprinting, but rather an exceedingly clean, tight, "fast"/energetic, and of-a-piece sound. Being that they also thrive on complex music and exhibit a marked sense of ease there's very often the sensation of simplicity to the presentation; it may at first lead one to believe something's missing, but on closer scrutiny there's quickly the reverse effect of feeling everything clearly laid bare, and emanating from a very stable and calm background. Unfiltered, you may say, yet musically very engaging.
Hope this helps...
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