The problem with controlling reflections with damping is that it damps all reflections, not just the very early ones. This is wrong. It's only the first one that you don't want, the rest are positive. Only a narrow directivity does this.
Absorption very near and around the loudspeaker would solve that "problem".
Best, Markus
Yes but in my mind I never understood all the hoop-la over them. The long pole in my system is the Room/Speaker interface or the speakers themselves. That's where you get the most improvement and bang for your buck. Cables are way down there in what really matters for good sound in my livingroom. I quess once your satisfied you can always go deeper but there comes a point where it just doesn't matter all that much and the changes are just that changes. If you can't say for sure which changes are for better or worse you are just wasting your time. As far as I am concerend the little deversion to speakers is what really matters anyway amd a much more important topic of conversation.
Rob🙂
Markus
I half agree. I believe in heavy absorption "back" of the speakers, but nothing forward of the speakers. If this is what you meant by "very near and arround" then I agree. Forward of the speakers should be almost as live as possible as long as the speakers can be set such that the Very early reflections are surpressed. Usually this does require floor and ceiling treatment since these are seldom far enough away. But perceptually we don't like vertical reflections anyways - the two ears are in the horizontal plane.
Well i'm pleased to see that someone has managed to explain the problem in a simple way & you are beginning to understand, cheers Cliff 😉 Yes unfortunately the test was sighted as it was myself the swapped the cables. However i didn't expect a lapped screen 3mm thick balanced cable costing £2.50 to outperform what would have been a homemade cable with £3.50 of wire & 2 x £5 connectors. It was a simple experiment & quite enlightening. I think the big difference was the fact that the MIDI cable was a steady 110 ohm impedance unlike phono cables which are all over the place impedance wise.
The beers are going down my neck as i type
Heard the same thing myself from the same CD manufacturer stamped in Germany 🙄
Well it looks like you hit the nail on the head JD, spot on! I compared some original recordings of Fax records CDs to the Ambient World re-issues (same master i assume) & the original LTD editions sounded different & better 😀
Thanks for clearing that up..
Back to cables 🙂
Behind, all around and to some extend in front of the loudspeaker without obstructing the direct wave.
Here's some data with a sheet of open cell foam lying on top of the speaker:
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Without absorber:
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Absorber:
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There's some reduction of reflections at other points in time too:
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Best, Markus
The one that you show the major reduction is was clearly the back wall. Otherwise I don't think that data contradicts what I said at all.
No Sir. The only thing that changed between measurements was the absorber on top of the speaker! The peak is after 6.44 ms (2.22 m).
It wasn't my intention to contradict anything you said. Just wanted to make sure that we speak of the same thing and that absorption very near to a speaker has its merits.
Best, Markus
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I'm not quite sure what you are saying. Those "phono" cables have varying impedance? How does that work? If they were just normal cables the impedance will not vary with audio signals.
I have one word for those that think digital cables need to be so special: MADI
If digital cables for 2 channels of audio sent 6 feet need to be special how can they send 64 channels of 48 khz/24 bit audio 2km (yes 2000 meters) down a single nothing special coaxial cable? And MADI is used by the best pro manufacturers in the world. (Studer, AMS Neve, SSL, Euphonix, Fairlight)
If digital cables for 2 channels of audio sent 6 feet need to be special how can they send 64 channels of 48 khz/24 bit audio 2km (yes 2000 meters) down a single nothing special coaxial cable? And MADI is used by the best pro manufacturers in the world. (Studer, AMS Neve, SSL, Euphonix, Fairlight)
My mistake. That is impressive. Not my preference for "how" to fix the ceiling refdlection, but it works for you I guess.
Phono cables are not designed with any specific impedance, they are just interconnects. When you are dealing with high frequencies or should i say square waves at a pretty high frequency you need to have a cable & connectors designed to run at a specific impedance. Effectively you are dealing with RF & no longer audio, if all cables, connectors & the receiving impedance match then things get along fine.
Anything with a phono connector in this instance must be pretty dubious, why do you think all the manufacturers of digital audio came up with AES-EBU to get round this problem? It's an international standard that supercedes the standard SPDIF standard using phono connectors as they aren't a constant impedance.
I'm sure they didn't develop it for any reason than to be an improvement over phono interconnects between transports & DACs. My ears say the same 😉
lol... Some people use RG58 for cables, some use 75 ohm cable instead of RG58 which is 50 ohm. Now go around & look for specific impedance of phono connectors.
I don't need to do a damn thing in this respect. If you can find manufacturers quoting specific impedance of there phonos you are doing much better than me 😀 Remember that BNC connectors are available with different impedances, wouldn't want to get the wrong ones would we 😉 Phonos have no specific impedance simply because they were never designed to be used to carry RF 🙂 Hense they don't work as well as something that has a specific impedance & is designed for a certain job, like AES-EBU balanced interconnects.
I havent read this whole thread 😀 but have read the last few pages about room reflections and am kinda (but not completely) surprised that no one has mentioned one of the best ways to deal with nasty reflections: diffusion. (Or has there been some new acoustics Ive missed?)
Theres usually a range of RT60 (room reverb time) that is optimal for music listening (anechoic sucks) and this is what determines the amount of absorbtion in the room. (and a lot of domestic rooms are already in that range from the furnishings) after that use diffusion to fix the unwanted reflections.
Theres usually a range of RT60 (room reverb time) that is optimal for music listening (anechoic sucks) and this is what determines the amount of absorbtion in the room. (and a lot of domestic rooms are already in that range from the furnishings) after that use diffusion to fix the unwanted reflections.
While this is correct let's not take things too far. It all depends on the data rate, or the frequency of the sample rate. RCA cables, if they are not totally junk, are just fine for 44.1 kHz data, and if you use RCA video cables (like I used to) then there is simply no problem. They can't do higher data rates than that, agreed. As long as the data is received by the DAC in halfway decent condition, it is going to get decoded and clocked out without a problem. Your thinking that you can hear problems is not likely unless your cable was so bad that it was simply not allowing the data to get to the DAC.
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