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Multi-Way Conventional loudspeakers with crossovers

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Old 15th October 2010, 07:11 AM   #4871
soongsc is offline soongsc  Taiwan
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Quote:
Originally Posted by AllenB View Post
If you're talking about tweaking the damping factor of the cartridge load by adjusting the cable capacitance, yes, a worthwhile endeavour. Since I learned about that one, I wouldn't run without.
No, not exactly that. All interconnects.
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Old 15th October 2010, 01:23 PM   #4872
doug20 is offline doug20  United States
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There are a few companies that do that. Not to turn this into a cable thread, my point is the cause of problem isn't always where you think it is. Only when we improve certain aspects technically will we gradually know what we really solved audibly. There are two ways harsh sounds will go away, one is when they are masked by other sounds, another is when they really go away due to a problem solved.
So is the cable mod a masking or is it solving the problem?

Im not as much interested in a cable debate here Im chasing down the "harsh sound" issue. Im thinking its all about the impedance issues of the horn and CD around the XO so wouldnt a Zobel solve this issue more then the cables or we just adding a "network" to our cables effectively doing the same thing?

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Old 15th October 2010, 01:36 PM   #4873
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Impedance issues also exist in interface between equipment. Zobels solve issues with the speaker. Acoustic impedance issues relate with horn/guide design. Each step of the interface needs to be considered. Cable mod can create masking, this is true if not done to the right characteristics. I find quite a narrow range of optimum performance, and am still trying to figure out why the characteristic changes with time.
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Old 15th October 2010, 01:45 PM   #4874
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Feel free to point me to some solutions, I want to solve this harshness in any way possible.

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Old 15th October 2010, 02:34 PM   #4875
soongsc is offline soongsc  Taiwan
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It's not easy, harshness can be problems in different places, and the description is relative. For example, I sent a pair of interconnects to someone in Australia to get some opinion. At that time, I did not think it was harsh or coarse. But one comment that came back was "it is more harsh and coars compared with what I'm used to", only when I came up with different combination that sounded better did I realise what he was referring to. The cable that sounded better was a tuned RG316 cable. This is about all I can talk about for now. However, another old colleague of mine using one of the early sample speaker that is being developed thinks the "harsh and coarse" cable is better. What can I say.

Note that I did not just jump into this thing originally. But going from speaker, to amp, to interconnect during development of a small active speaker. A few years of work behind all this. So the first place I would look into is still the speakers. Then smooth the speaker impedance (I even do it for the low frequency humps in ported enclosures, but it may not be necessary for most). The cable side I really cannot reveal information on this until, the technology is openly available and applied by others.
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Old 15th October 2010, 04:58 PM   #4876
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But, there are obvious and audible differences to the different formats. I listen to a lot of Pandora lately and it's not bothersome, though compared to CD it's noticeably flatter and fatiguing. LP is still another step up.

But agreed with your point- speakers rule all.
Check this out Badman: http://itunes.apple.com/us/app/abxte...371434492?mt=8 A neat little ABX tester for your iPhone/Pad/Touch. What I found so interesting doing this is how much more I hear compression effects through speakers than through headphones. With headphones, 128kbps AAC was not reliably discernible from an uncompressed WAV. With speakers, 128kbps AAC is easily discernible.

Doug, a polar graph of your speakers would probably be more telling of any harshness. I agree with others that the speaker/room are probably 95% of what you hear. If you use an analog source, those numbers will change.

Dan
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Old 29th October 2010, 12:20 PM   #4877
JLH is offline JLH  United States
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Default New B&C Speakers DE5 compression driver

While looking around at the available compression drivers, I noticed that B&C has released two new smaller format compression drivers. The DE5 and DE7 are 0.5" and 0.75" exit compression drivers. Wouldn't having a smaller throat OS waveguide provide an advantage over the normal 1" that has been used up until now? The DE5 looks like a pretty decent driver.

http://www.bcspeakers.com/BC_ADMIN/p...?id=0000000190
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Old 29th October 2010, 01:16 PM   #4878
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There are pros and cons. A smaller throat pushes the HOMs up in frequency, and also tends to have better HF response, but it also raises the LF point for which the waveguide is useful. The ideal is to match the LF requirements with the need to match the woofer directivity at the crossover point, while pushing the HOMs to dominately above say 10 kHz. whilke having "sufficient" HF capability to allow for only one HF device. The 1" seems to be somewhat ideal in this regard - 1.5 & 2" throats do not have a satisafcatory response above 8-10 kHz, and I suspect that a smaller throat would not have a satisfactory LF capability for my bigger systems the Summa and the Abbey. The thing is that it's so much easier to just stick with one thorat size for all models and 1" becomes the only option under these circumstances.
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Old 29th October 2010, 06:03 PM   #4879
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Earl, I have several times quoted you as suggesting that HOMs are an issue above 10 kHz, primarily, but never found the specific citation.

Do you confirm?

Others here are attributing "Honk" to HOMs, but to me, that's a decade lower in frequency, and while the reflections responsible for it may also generate HOMs, they are an artifact, i.e., not the fundamental source of the distortion we typically recognize as "Honk?"

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Old 29th October 2010, 08:10 PM   #4880
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No, that is not entirely correct. The first axi-symmetric HOM for a 1" throat OS waveguide occurs at about 7 kHz. But the non-axisymetric ones cut-in at much lower frequencies. Clearly the most significant ones in an OS waveguide will be axisymmetric and the majority are above 10 kHz.

In non OS waveguides or horns none of the above is necessarily true and the HOMs would occur at much lower frequencies.

To elliminates the HOMs one has to elliminate the internal reflections as well so the two go hand-in-hand. The point is that to elliminate the "honk" you have to minimize the HOMs as well and it would be a chicken and egg game to figure out which was the primary and which was the secondary cause and effect if such a distinction is even possible.
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