 |
 | Home | Contact Us | FAQ | Search & Site Map | Link to Us |
 | Sign In | Join | Other 45 Sites in Network |
Car Forum / Driving, Maintenance, Tuning / Car Audio / October 2006Time Alignment Questions
I have been given an Eclipse CD8454 to evaluate. I've never had the opportunity to use time alignment before. Before I ask the questions that makes me sound stupid, I have to pat myself on my back first. Using my ears only, I found that a .9 millesecond delay sounded best for my front soundstage. After getting out the tape measure and doing the math I found the recommended dealy to be .89 milleseconds. Not bad for my first exposure to TA! Not really knowing what I was doing, I added delay to the passenger side speakers and it sounded pretty good. Then I started to think... Common sense tells me that if speaker A (on the driver's side) is only 4 feet from your left ear and speaker B (on the passenger's side) is 6 feet, then you would need to add delay to speaker A since it's closer, correct? So that's what I did. Of course, it did not sound as good as adding delay to the passenger side, which really puzzled me. At this point I decided to get out the head unit's owners manual. It says to select the speaker that is FARTHEST away from you and add the appropriate delay time. I tried this and it sounded much better. But it still puzzled me. 1) Am I correct that, literally, you would have to ADD delay time to the speaker that is CLOSEST to you to make sounds from both speakers reach your ears at the same time? 2) If I'm correct, then the head unit is backwards in it's layout. If I choose the speaker FURTHEST away from me and add delay time, it's actually adding delay time to the CLOSEST speaker? Very confusing! 3) Unrelated question. If I add equal delay times to BOTH front speakers, am I correct in assuming that with the right delay time, whatever that happens to be, the low frequencies from my subwoofers will arrive up front at the same time as my front speakers? I've been messing around with this, and it seems that by adding 2 milleseconds to both front speakers makes the bass sound a lot tighter. I even reversed the subs' polarity which sounds....interesting. I haven't decided whether I like it or not yet. Anyway, any comments about this or any other TA issues would be extremely appreciated!! Tony  SignatureSony CDX C90 Head Unit, Phoenix Gold ZX475ti, ZX450 and ZX500 Amplifiers, Phoenix Gold EQ-232 30-Band EQ, Dynaudio System 360 Tri-Amped In Front and Focal 130HCs For Rear Fill, 2 Soundstream EXACT10s In Aperiodic Enclosure >I have been given an Eclipse CD8454 to evaluate. I've never had the >opportunity to use time alignment before. Before I ask the questions that [quoted text clipped - 36 lines] > > Tony Your thinking sure complies with my own on all accounts, it's the method I used on my alpine, put the delay in the closest speaker.. one of the nicer aspects of time correction I liked was that I could also put a huge delay on my rear fill, with everything faded just right toward the front it stops sounding like a car and more like a nice, big room ;) My method for sorting out the delay in the front was to sit in my usual driving position, put on a good vocal track with it faded all the way to the front so the rear fill doesn't interfere, and I adjust the delay until it sounds like the vocals are coming from a center channel just under my hood, you can hear it drift from the right to left as the delay is increased.. sounds sweet now..nice and centered.. My advice, put away the tape measure, make it sound good to you.... because music is art, not science. Please people!! There are quite a few of you out there that I KNOW have a substantial amount of knowledge about this particular subject. Do share!! Tony SignatureSony CDX C90 Head Unit, Phoenix Gold ZX475ti, ZX450 and ZX500 Amplifiers, Phoenix Gold EQ-232 30-Band EQ, Dynaudio System 360 Tri-Amped In Front and Focal 130HCs For Rear Fill, 2 Soundstream EXACT10s In Aperiodic Enclosure >I have been given an Eclipse CD8454 to evaluate. I've never had the >opportunity to use time alignment before. Before I ask the questions that [quoted text clipped - 36 lines] > > Tony 1) Am I correct that, literally, you would have to ADD delay time to the > speaker that is CLOSEST to you to make sounds from both speakers reach > your ears at the same time? Yes. You normally make whatever driver is the furthest from you the reference. For instance, in my car the sub is the furthest away in one corner of the trunk. That distance is something like 78". You set delay for that driver to 0 ms. then, SUBTRACT the distance from each other driver from that 78" to get the difference in distance that you will compensate for. So, if say the passenger mid is 37 inches from your right ear, subtract that to get a 41" pathlength difference. It is that difference which you convert to ms and that becomes your time delay for the front right mid. Same thing applies to the other drivers. > 2) If I'm correct, then the head unit is backwards in it's layout. If I > choose the speaker FURTHEST away from me and add delay time, it's actually > adding delay time to the CLOSEST speaker? Very confusing! See above, if following that approach doesn't resolve your problem, perhaps the HU mfr. has "inverted" the operating logic somehow. > 3) Unrelated question. If I add equal delay times to BOTH front speakers, > am I correct in assuming that with the right delay time, whatever that [quoted text clipped - 5 lines] > yet. Anyway, any comments about this or any other TA issues would be > extremely appreciated!! Get the time alignment dialed first, then crossover settings and levels. Once you get all that stuff set right, then try playing with all the various phase combinations. I find that inverting the phase to my sub makes its output more obvious up front, but putting it back to normal sounds more musical i.e. in-phase with the front end. Fortunately, my car does not have much if any mid-bass suckout to speak of so I have been able to set up all the drivers in phase and get a nice flat front stage and good localization for vocals etc. Different drivers or driver locations or impact from in-car acoustic problems can screw with that of course. I hadn't tuned one of these Sony Mobile ES DSP systems for a few years but having gone through the drill again after finally installing the necessary components on my current ride reminds me all over again how good a car can sound when you get all the basics right. Other than fabbing a permanent sub box, the install is complete and I am really loving having a real audio system again. This one is considerably more powerful than the last system I built, and damn is it fun being able to jam the volume control all the way into the stops without a hitn of clipping or driver distress. Makes me get goosebumps all over when I'm driving and a good song comes on and the system's cranked, and reminds me ll over again why I have stayed in this industry for 27 years. JD >Please people!! There are quite a few of you out there that I KNOW have a >substantial amount of knowledge about this particular subject. [quoted text clipped - 4 lines] > > > I hadn't tuned one of these Sony Mobile ES DSP systems for a few years but having gone through the drill again after finally installing the necessary components on my current ride reminds me all over again how good a car can sound when you get all the basics right. Other than fabbing a permanent sub box, the install is complete and I am really loving having a real audio system again. This one is considerably more powerful than the last system I built, and damn is it fun being able to jam the volume control all the way into the stops without a hitn of clipping or driver distress. Makes me get goosebumps all over when I'm driving and a good song comes on and the system's cranked, and reminds me ll over again why I have stayed in this industry for 27 years. It's great having loads of power. Feeling the snare drum shake your pants leg tells you you're there. But it's not so good if your speakers can't quite handle it. :( (blew my second a/d/s/ 4" driver in about six months time) I am running this for power/drivers: a/d/s/ 346cs components up front PPI PCX 280 driving the tweeters PPI PCX 4125 driving the 6.5" mids, and rear fill PPI DCX 690C for rear fill (off most of the time) PPI DCX 124 in a sealed enclosure for bass PPI PCX 1500 to drive the sub. So, I have a little over 100 watts per channel for the tweeters, about 160 watts per mid or rear fill channel, and 1,000 watts of sub power. Can you say, DAMN! Interesting you mentioning the snare drum, one of the discs I've played with in tuning this thing is the Sheffield Drum and Track CD, and I have never heard it reproduced tighter, more realistically, or at such bigger than life levels in my 27 years in the business... JD like our PPI ads say, "if power corrupts, Precision Power corrupts... Absolutely" P.S. Drop me your address again, I think I have a few of those 4 replacement drivers left >>I hadn't tuned one of these Sony Mobile ES DSP systems for a few years but >> [quoted text clipped - 17 lines] > > > I am running this for power/drivers: > [quoted text clipped - 8 lines] > 160 watts per mid or rear fill channel, and 1,000 watts of sub power. > Can you say, DAMN! That's pretty impressive. I have 3-way component set of the older 3-series a/d/s/ drivers being run by two channels from the a/d/s/ P840 (tweeters), four channels from the P840 (4" mids), and two channels from the Orion XTR8004 (6" woofers). So that's about 40 wpc for the tweeters, maybe close to 100 for mids, and 125 for the woofers. I've got Morel woofers in the back being driven by the remaining channels from the Orion and dome mids being driven by the remaining two channels from the P840. So in total, something like 265 per channel for the fronts and 165 for the rears. The first driver didn't really blow - the dustcap just shot off. I think I told you about that. The second one really did blow. One of the problems is that I tend to like to crossover my mids a bit lower than recommended. For example, when I had my 3-way set of Morels, I tried to get that little dome mid down to about 500Hz, but it wasn't very happy there. Reluctantly, I had to put it back up to the recommended 700Hz and let the woofer handle the rest. These a/d/s/ 4's are quite a bit more resilient of course, so I've been running them down to about 400 Hz I think. They seem to be distorting well before the other speakers though, and that Orion amp that's running the 6" drivers seems to be more powerful than the 25 watt difference that the ratings imply, so I'll probably raise the crossover point a bit. I'm just not very impressed with the power handling capabilities of these 4" mids, though the woofers seem to be more than adequate in that respect. Speaking of time alignment, I've been toying with the idea myself. Not sure how I would implement it though. I have no idea what's around these days. I'd need something with an optical input to go right before my DAC. Ideally I'd stick with a Zapco piece just to match my DAC (the real reason is that I have extra unused outputs on the power supply for the DAC), but I don't think they make one. Does Directed have anything like this? > P.S. Drop me your address again, I think I have a few of those 4 > replacement drivers left zarellam at twcny dot rr dot com. Much appreciated. > Speaking of time alignment, I've been toying with the idea myself. Not sure > how I would implement it though. I have no idea what's around these days. > I'd need something with an optical input to go right before my DAC. Ideally > I'd stick with a Zapco piece just to match my DAC (the real reason is that I > have extra unused outputs on the power supply for the DAC), but I don't > think they make one. Does Directed have anything like this? Duh, brainfart. Obviously, it can't go before the DAC. Anyway, it would have to go after the DAC which essentially renders the DAC useless. So it would be nice if there was a time alignment/DAC piece all in one. John Durbin wrote: "See above, if following that approach doesn't resolve your problem, perhaps the HU mfr. has "inverted" the operating logic somehow." That was my guess. It's obviously a big typo that the manual editors didn't catch. It sure was hell for someone that knows nothing about time alignment. I figured it out on my own after a few cussing sessions because not only did it defy logic, but it just didn't sound right either. My imaging has HUGELY improved with the addition of T.A. Sounds are more distinctly heard at the far right and left of the soundstage where before they lacked presence. The depth has also improved greatly...everything sounds like it's coming from just above dash level up front near the windshield. I also assume there's some sort of relationship to relative phase between different speakers and T.A.? I got out my IASCA setup CD and was listening to the vocal and polarity tracks. Before, when they demonstrated polarity with a human voice there was a doubt in my mind as to what exactly sounded "in phase" and "out of phase". Now, the difference is night and day. Also, the location of the vocals are extremely well defined. In reading the booklet that comes with the setup CD, things are making MUCH more sense now that I can hear and pinpoint the differences. It's an amazing experience. "This one is considerably more powerful than the last system I built, and damn is it fun being able to jam the volume control all the way into the stops without a hitn of clipping or driver distress. Makes me get goosebumps all over when I'm driving and a good song comes on and the system's cranked, and reminds me ll over again why I have stayed in this industry for 27 years." Oh god yes. I've got my Dynaudio 3-ways tri-amped. I have dedicated amp channels delivering somewhere in the range of 75w to each speaker...conservatively. The 8-inch midwoofers in the doors are heavily damped. They absolutely pound. My system at full volume scares me. I literally turn down the volume because I know I'm damaging my ears at times. The subs in the back blend in perfectly with my front soundstage...it sounds as if they're not in the trunk at all but in my front doors. Sweet. P.S. I bought the Eclipse. Tony SignatureEclipse CD8454 Head Unit, Phoenix Gold ZX475ti, ZX450 and ZX500 Amplifiers, Phoenix Gold EQ-232 30-Band EQ, Dynaudio System 360 Tri-Amped In Front and Focal 130HCs For Rear Fill, 2 Soundstream EXACT10s In Aperiodic Enclosure nice... rock on! JD >John Durbin wrote: "See above, if following that approach doesn't resolve >your problem, perhaps the HU mfr. has "inverted" the operating logic [quoted text clipped - 39 lines] > > I have an Eclipse av8533 with time alignment and I believe it came with s conversion chart, x amount of feet = x amount of delay. Well I lost it and can't seem to get from Eclipse (go figure) Is the conversion a standard type of measurement? Wouls anyone know where I could get one??????? I have an Eclipse av8533 with time alignment and I believe it came with a conversion chart: x amount of feet = x amount of delay. Well I lost it and can't seem to get from Eclipse (go figure) Is the conversion a standard type of measurement? Wouls anyone know where I could get one??????? |
Reply to this Message |
 Sign In
 Join
 My Latest Posts My Monitored Threads My Blog My Photo Gallery My Profile My Homepage Start New Thread Enable EMail Alerts Rate this Thread
|
©2008 Advenet LLC Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.