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Post by Talley on Jan 31, 2016 19:46:01 GMT -5
Carpet only offers a -2 to -3db at most for reduction of first waves. If I can ever build a dedicated room my entire floor space will be a sunk in design to house acoustics and the floor will be of a perferated type to allow everytying to pass t hrough. Talk about a vacuming hell though. |
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Post by lionear on Feb 1, 2016 1:46:16 GMT -5
I believe the math involved in room correction is very complex and you have to apply the math iteratively - each time you run it, you feed the previous result into it, and you'll get a solution that's closer and closer to the "right answer". I believe the first generation of room correction equipment did it four times and called it good. May be that number is more now. But no matter what, it's going to be a finite number, and the result will always be an approximation. How many iterations are enough? I don't know the answer to this.
In addition, I believe REG (musician, audiophile and math professor at UCLA) said that the room correction software can only take on the first echo into account. So good room acoustics will still be important. One may need to suit the room's acoustics to what the software can solve easily.... May be the room has to be over-damped. And may be one needs to use speakers that have a narrow dispersion to minimize the echo - but that will mean there will only be on sweet spot.
And finally, the aim of digital room correction programs seems to be to get a flat frequency response. But at what cost? I believe there are other factors that need to be taken into account. For example, one way to get very flat response from speakers is to use a lot of drivers and crossovers with very steep slopes. But steep slopes require use of 3rd or 4th order crossovers, and you're going to affect the phase fidelity.
And I've been a bit puzzled by the adjustment process with Dirac. The idea seems to be: get a microphone, play a test signal so that Dirac can calibrate the mic, then calibrate the room. But using Dirac to calibrate the mic, then using the mic + Dirac to correct the room... is circular. Shouldn't one be using a mic that has been calibrated via an independent process - such as in an anechoic chamber, and adjusted via hardware adjustments to it? And then you upload the numbers for that mic (from the testing in the anechoic chamber for that specific mic) into Dirac? (I'm no expert on Dirac so I'll say "Sorry" in advance, if this is incorrect.)
I think the emphasis on HT comes from the fact that the audio from movies is less complex than a full-blown stereo soundstage - especially when it comes to phase info. With HT, all the dialog, incidental sounds and music soundtrack are mixed in individually. So the sound just involves panning and volume. But when it comes to full-blown stereo soundstage, all the info has to be recorded "at once", and then played back "in full". I believe this will present more of a challenge to room correction software.
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klinemj
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Post by klinemj on Feb 1, 2016 6:18:42 GMT -5
I believe the math involved in room correction is very complex and you have to apply the math iteratively - each time you run it, you feed the previous result into it, and you'll get a solution that's closer and closer to the "right answer". I believe the first generation of room correction equipment did it four times and called it good. May be that number is more now. But no matter what, it's going to be a finite number, and the result will always be an approximation. How many iterations are enough? I don't know the answer to this. In addition, I believe REG (musician, audiophile and math professor at UCLA) said that the room correction software can only take on the first echo into account. So good room acoustics will still be important. One may need to suit the room's acoustics to what the software can solve easily.... May be the room has to be over-damped. And may be one needs to use speakers that have a narrow dispersion to minimize the echo - but that will mean there will only be on sweet spot. And finally, the aim of digital room correction programs seems to be to get a flat frequency response. But at what cost? I believe there are other factors that need to be taken into account. For example, one way to get very flat response from speakers is to use a lot of drivers and crossovers with very steep slopes. But steep slopes require use of 3rd or 4th order crossovers, and you're going to affect the phase fidelity. And I've been a bit puzzled by the adjustment process with Dirac. The idea seems to be: get a microphone, play a test signal so that Dirac can calibrate the mic, then calibrate the room. But using Dirac to calibrate the mic, then using the mic + Dirac to correct the room... is circular. Shouldn't one be using a mic that has been calibrated via an independent process - such as in an anechoic chamber, and adjusted via hardware adjustments to it? And then you upload the numbers for that mic (from the testing in the anechoic chamber for that specific mic) into Dirac? (I'm no expert on Dirac so I'll say "Sorry" in advance, if this is incorrect.) I think the emphasis on HT comes from the fact that the audio from movies is less complex than a full-blown stereo soundstage - especially when it comes to phase info. With HT, all the dialog, incidental sounds and music soundtrack are mixed in individually. So the sound just involves panning and volume. But when it comes to full-blown stereo soundstage, all the info has to be recorded "at once", and then played back "in full". I believe this will present more of a challenge to room correction software. DIRAC uses a calibrated mic. When using it, you do set levels to make sure the test tone is not too loud and noit too quiet, but that is it. Mark |
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Post by Talley on Feb 1, 2016 7:22:01 GMT -5
I believe the math involved in room correction is very complex and you have to apply the math iteratively - each time you run it, you feed the previous result into it, and you'll get a solution that's closer and closer to the "right answer". I believe the first generation of room correction equipment did it four times and called it good. May be that number is more now. But no matter what, it's going to be a finite number, and the result will always be an approximation. How many iterations are enough? I don't know the answer to this. In addition, I believe REG (musician, audiophile and math professor at UCLA) said that the room correction software can only take on the first echo into account. So good room acoustics will still be important. One may need to suit the room's acoustics to what the software can solve easily.... May be the room has to be over-damped. And may be one needs to use speakers that have a narrow dispersion to minimize the echo - but that will mean there will only be on sweet spot. And finally, the aim of digital room correction programs seems to be to get a flat frequency response. But at what cost? I believe there are other factors that need to be taken into account. For example, one way to get very flat response from speakers is to use a lot of drivers and crossovers with very steep slopes. But steep slopes require use of 3rd or 4th order crossovers, and you're going to affect the phase fidelity. And I've been a bit puzzled by the adjustment process with Dirac. The idea seems to be: get a microphone, play a test signal so that Dirac can calibrate the mic, then calibrate the room. But using Dirac to calibrate the mic, then using the mic + Dirac to correct the room... is circular. Shouldn't one be using a mic that has been calibrated via an independent process - such as in an anechoic chamber, and adjusted via hardware adjustments to it? And then you upload the numbers for that mic (from the testing in the anechoic chamber for that specific mic) into Dirac? (I'm no expert on Dirac so I'll say "Sorry" in advance, if this is incorrect.) I think the emphasis on HT comes from the fact that the audio from movies is less complex than a full-blown stereo soundstage - especially when it comes to phase info. With HT, all the dialog, incidental sounds and music soundtrack are mixed in individually. So the sound just involves panning and volume. But when it comes to full-blown stereo soundstage, all the info has to be recorded "at once", and then played back "in full". I believe this will present more of a challenge to room correction software. Man there is so much recording out there that are done on multiple passes and are finalized in the studio my mixing engineers. It's hardly ever recorded "at once" even excellent recordings. |
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Post by vneal on Feb 1, 2016 7:30:02 GMT -5
As long as there are four walls, a ceiling and a floor we will need some room correction
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Post by Talley on Feb 1, 2016 8:39:49 GMT -5
As long as there are four walls, a ceiling and a floor we will need some room correction Right... Acoustical treatment = room correction lol |
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Post by pedrocols on Feb 1, 2016 9:08:54 GMT -5
I wonder if recording studios use any room treatment....? Of course this is a rethorical question...
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Post by lionear on Feb 1, 2016 10:47:29 GMT -5
Talley Yes, I think that's something that the whole hobby has lost sight of. At the highest end of hi-fi, we need the best recordings that justify the best gear. In the old days (the 80's and 90's) reviewers in magazines like The Absolute Sound would list the LP's that they used, and exactly what they heard on what track. We could never afford the equipment, but we could get those LP's. And we'd see if we could hear whatever they described, too - and to what extent. And we can thank the reviewers for discovering the astounding sound of old LP's (like the Mercury Living Presence LP's, and RCA Living Stereo LP's). I was listening to "Music for Bang, Baaroom and Harp" (RCA LSP-1866) last night - it was on HP's Super Disk list. The LP was recorded in 1958 at Orchestra Hall, Chicago - not a studio, most probably via all tube gear, no Dolby noise reduction on the tape (not invented yet), and it might have all been done in one take. I ran it through my VPI record cleaner even though it didn't look like it needed it. It's not totally silent. But the sound is absolutely astounding. Now THAT is soundstage. From a 58 year old LP! (Probably the best $4 I've ever spent.)
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Post by monkumonku on Feb 1, 2016 10:59:04 GMT -5
Talley Yes, I think that's something that the whole hobby has lost sight of. At the highest end of hi-fi, we need the best recordings that justify the best gear. In the old days (the 80's and 90's) reviewers in magazines like The Absolute Sound would list the LP's that they used, and exactly what they heard on what track. We could never afford the equipment, but we could get those LP's. And we'd see if we could hear whatever they described, too - and to what extent. And we can thank the reviewers for discovering the astounding sound of old LP's (like the Mercury Living Presence LP's, and RCA Living Stereo LP's). I was listening to "Music for Bang, Baaroom and Harp" (RCA LSP-1866) last night - it was on HP's Super Disk list. The LP was recorded in 1958 at Orchestra Hall, Chicago - not a studio, most probably via all tube gear, no Dolby noise reduction on the tape (not invented yet), and it might have all been done in one take. I ran it through my VPI record cleaner even though it didn't look like it needed it. It's not totally silent. But the sound is absolutely astounding. Now THAT is soundstage. From a 58 year old LP! (Probably the best $4 I've ever spent.) Those old Mercury and RCA recordings are amazingly good. Tape hiss is a distraction but otherwise they are clean, have excellent dynamics, imaging, etc. and are just plain good reproductions of the performances back then. |
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Post by lionear on Feb 1, 2016 11:01:52 GMT -5
Talley Yes, I think that's something that the whole hobby has lost sight of. At the highest end of hi-fi, we need the best recordings that justify the best gear. In the old days (the 80's and 90's) reviewers in magazines like The Absolute Sound would list the LP's that they used, and exactly what they heard on what track. We could never afford the equipment, but we could get those LP's. And we'd see if we could hear whatever they described, too - and to what extent. And we can thank the reviewers for discovering the astounding sound of old LP's (like the Mercury Living Presence LP's, and RCA Living Stereo LP's). I was listening to "Music for Bang, Baaroom and Harp" (RCA LSP-1866) last night - it was on HP's Super Disk list. The LP was recorded in 1958 at Orchestra Hall, Chicago - not a studio, most probably via all tube gear, no Dolby noise reduction on the tape (not invented yet), and it might have all been done in one take. I ran it through my VPI record cleaner even though it didn't look like it needed it. It's not totally silent. But the sound is absolutely astounding. Now THAT is soundstage. From a 58 year old LP! (Probably the best $4 I've ever spent.) Those old Mercury and RCA recordings are amazingly good. Tape hiss is a distraction but otherwise they are clean, have excellent dynamics, imaging, etc. and are just plain good reproductions of the performances back then. You hear hiss? |
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Post by monkumonku on Feb 1, 2016 11:17:55 GMT -5
Those old Mercury and RCA recordings are amazingly good. Tape hiss is a distraction but otherwise they are clean, have excellent dynamics, imaging, etc. and are just plain good reproductions of the performances back then. You hear hiss? I have many of the CD's, not the vinyl, and I can hear hiss on the silent or very quiet passages. It's not real loud but it is there. Doesn't really bother me but I do notice it. |
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Post by Talley on Feb 1, 2016 16:57:48 GMT -5
I find the old 50s-70s direct to disc recordings to be the best recorded music ever. No mistakes... just play and a microphone to the cutter. This album is what turned me into jazz/audiophile wants/desires and got me started on acoustics and such. I was 15 when I first heard it: www.amazon.com/King-James-Version-Harry/dp/B000025RKX/ref=tmm_acd_swatch_0?_encoding=UTF8&qid=&sr=shortly after I bought the master handbook of acoustics and was overwhelmed but understood the basics. Wasn't until a couple years ago I could afford much, spent all that time from now till then building my career, starting a family, purchased a home... etc. Now I can enjoy  |
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klinemj
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Post by klinemj on Feb 1, 2016 17:27:59 GMT -5
I have many of the CD's, not the vinyl, and I can hear hiss on the silent or very quiet passages. It's not real loud but it is there. Doesn't really bother me but I do notice it. Miles Davis Kind of Blue has a fair amount of tape hiss, but the overall sound is great even with the hiss. Mark |
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Post by DavidR on Feb 1, 2016 22:30:14 GMT -5
I have many of the CD's, not the vinyl, and I can hear hiss on the silent or very quiet passages. It's not real loud but it is there. Doesn't really bother me but I do notice it. Miles Davis Kind of Blue has a fair amount of tape hiss, but the overall sound is great even with the hiss. Mark I have it on vinyl. No hisssss. Great album. The XSP-1 G2 has a great phono section. |
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Post by novisnick on Feb 1, 2016 22:34:02 GMT -5
Miles Davis Kind of Blue has a fair amount of tape hiss, but the overall sound is great even with the hiss. Mark I have it on vinyl. No hisssss. Great album. The XSP-1 G2 has a great phono section.
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Post by JKCashin on Feb 1, 2016 22:54:40 GMT -5
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Post by Boomzilla on Feb 1, 2016 23:20:05 GMT -5
My audio amigo, Mr. novisnick, has generously agreed to bring his XSP-1 down with him the next time he visits. We'll fire up the DIRAC & see what changes result. Impress me sufficiently, & Emo may have yet another sale... |
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Post by Gary Cook on Feb 2, 2016 1:27:12 GMT -5
I have a UMC-200 for 5.1 movies which I have PEQ'd and a USP-1 for 2.1 stereo music. The room is pretty good acoustically, W2W carpet with acoustic insulation underneath, double heavy curtains, some treatment, cathedral ceilings with the L&R and sub facing out towards the dining room and the upper split level. It doesn't need a lot of correction which is a good thing as my PEQ'ing is far from expertise.
Cheers
Gary
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Post by monkumonku on Feb 2, 2016 10:10:15 GMT -5
Miles Davis Kind of Blue has a fair amount of tape hiss, but the overall sound is great even with the hiss. Mark I have it on vinyl. No hisssss. Great album. The XSP-1 G2 has a great phono section. There's hiss on the recording from the original master tape. Are you saying that the recording was processed to remove the hiss before being put on vinyl? |
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Post by DavidR on Feb 2, 2016 10:31:01 GMT -5
I have it on vinyl. No hisssss. Great album. The XSP-1 G2 has a great phono section. There's hiss on the recording from the original master tape. Are you saying that the recording was processed to remove the hiss before being put on vinyl? I'll listen to it today and listen for hiss. I've never detected it before. |
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