Have a good look at the LessLoss hookup cable (and coax and triax cable for that matter). Truly unique self-inductance cancelling properties due to the very complex geometery. I use the coax as interconnects in my main system and it is great stuff (I actually have the Boenicke Audio branded cables that use the Lessloss but he uses the outer layer as the conductor and the inner as the ground...because it sounds better so he says).
For you horn guys: What kind of compression driver are you using for high frequencies? Why that choice (if you know...)
- Thread starter morricab
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Can you take a picture of the backside of the compression driver? I might be able to figure out the brand if not the model from the photo.
Yes in their other models Ked but in the horn they have a proprietary CD, it Resembles some BMS drivers. This is a pic Brad.
I think this is not a BMS driver as it looks like nothing in their catalog. Also, on the PAP page for this speaker they don't actually state the crossover frequency. The 450hz seems to be with the full-range drivers (Tang Band and Voxativ).
The closest I have found is from Beyma:
https://www.beyma.com/en/products/c/compression-driver/1CD1114FE8/motor-cd-1114fe-8-oh/
https://www.beyma.com/speakers/Fich...s-data-sheet-compression-driver-CD-1114Fe.pdf
The back cover is nearly identical to yours but there are not push buttons and the Beyma is a ferrite magnet and yours looks to be Nd.
This one is even closer in design except it is a 1 inch exit, not 1.4 inch
https://www.beyma.com/en/products/c/compression-driver/1CD11ND8/motor-cd-11nd-8-oh/
https://www.beyma.com/speakers/Fich...ers-data-sheet-compression-driver-CD-11Nd.pdf
Maybe they got a custom driver from Beyma that is a mix of these two? I looked at a lot of other brands and no other are similar for the back cover to yours.
It also fits because PAP says the 1.4 inch compression driver uses polymer and both of these Beymas use PM4, which is a proprietary polymer of Beyma (probably a kind of polyamide).
The good news is that Beyma makes excellent drivers (really excellent).
I am still doubting that my Radian 475pbBe will actually beat my trusty old Beyma CP-350Ti
The CP755Ti is also ridiculously good (if in fact your driver is a Beyma, this would be an upgrade path as they should have similar exit angles, so matching with the horn would be easier).
https://www.beyma.com/speakers/Fich...ers-data-sheet-compression-driver-CP755Ti.pdf
However, it looks like the Re is different so it might impact the crossover somewhat.
Thanks Brad,
It does sound really good, I will try and discover more. The comment on crossover point for the horn was in an online review I read quite a while back. But I’ll try and get something more concrete out of Pureaudioproject. Still looking forward to you getting the radians in and what you find with them.
It does sound really good, I will try and discover more. The comment on crossover point for the horn was in an online review I read quite a while back. But I’ll try and get something more concrete out of Pureaudioproject. Still looking forward to you getting the radians in and what you find with them.
I think the cheapest default is the Tang Band full range driver...which is surprisingly good for low money. I would be interested in the Beyma AMT driver but I think they cross it over too low (1Khz). Based on what I read on DIY forums, it really only shines when used above 2Khz, then it is about the most linear driver in existence right up through 20Khz.
I tried to swap out the CP350Tis for the Radians only to find out that the Radian bolt holes are M6 and the Beymas are M5! So, I need to buy a couple of M6 bolts to mount the damn things!
Well, the funny thing I tried with my own DIY horn system is taking the CD down as low as 650Hz, which at the levels I listen it has no problems whatsoever, but I kept bumping it up. When I got to 1Khz it clicked into place. Going higher (even as little as 1100 or 1200 Hz) didn't sound as good, nor did crossing quite high like 3-4Khz. This was true whether I used the larger horn with larger CD or smaller horn/smaller CD (it is still rated down to 900hz (Iwata 600)). Perhaps this is just a good blending point for the dispersion patterns?
It depends on the driver, the Fc of your horn, and what design you want. You are doing TQWT. I don't know about that.
For dual woofer FLH, I can do anywhere between 200 to 700 for a three way depending on the driver. If I go below 500-550, size of JMLC increases too much, but can be done with other horns like tractrix. For a two way instead of a three way I just need to change the JMLC to a CD or to Markus klug's Altec multicell or to some wooden radial (which for me has highest WAF)
For dual woofer FLH, I can do anywhere between 200 to 700 for a three way depending on the driver. If I go below 500-550, size of JMLC increases too much, but can be done with other horns like tractrix. For a two way instead of a three way I just need to change the JMLC to a CD or to Markus klug's Altec multicell or to some wooden radial (which for me has highest WAF)
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TQWT. It's some kind of transmission line tapered bass, and apparently those who use it do use a high cut off
Have a look at the Voigt pipe. This design has been around since the 1930s and very popular indeed with the diy scene.
It is a TQWT, which stands for Tapered Quarter Wave Tube and was invented by Voigt a long time ago. It is a type of horn with mass loading (ie. resistance) at the mouth. This gives it characteristics like a horn but gets deeper bass from a shorter horn than a typical exponential horn. It is also based on standing waves, which a normal horn is not. What is interesting is that the depth of the bass is derived from the horn length and not from the resonance frequency of the driver (within reason). This means I can get 40Hz bass with a driver that has 65Hz resonance frequency.
What I have noted is that the bass power and punch is far greater for this type of horn than the more traditional folded (or straight) horn with the same frequency cutoff. Not sure why that is but most back loaded horns of the exponential type sound lightweight to me even though the length was suffcient to get to 35-40Hz. The bass power from my Odeons (TQWT) and my DIY based on Supravox (also TQWT) have superb punch, timing, speed and surprising bass depth (especially the Supravox box). It has become my box loading of choice, especially given how well it works with high sensitivity, low Qts drivers like the Supravox 215-2000 (99db and Qts of only 0.21). This driver shouldn't make any bass (it also has almost no excursion capability) but loaded into TQWT it is transformed...even thunderous bass sees no movement from the cone. The acceleration of this driver is impressive for an 8 inch cone.
Yes and no. It is a horn of conical proportions but it is a standing wave horn excitation rather than a compression chamber Throat/mouth type. There is some mass loading as well to give some characteristics of vented designs as well. A true transmission line is like a stuffed horn in reverse.
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