maxmercy Posted February 17, 2015 Report Share Posted February 17, 2015 Shred, Given the tools you work with are better than mine, care to run the oppo through its paces with my sinewave WCS tracks? Sounds like it could handle it, going by the above post. JSS Link to comment Share on other sites More sharing options...
Shredhead Posted February 18, 2015 Report Share Posted February 18, 2015 Sure, I'd be happy to Max. Just to show you guys how using the interface/DAW scope thing will sniff out clipping: Here are 2 waveforms of the same scene (HTTYD Dragon Crash) with the Sony AVR's subwoofer out and with the OPPO. On the Sony -MVL at 66 out of a possible 74maximum, 0dB sub trim, 5 speakers to small and x-over at 77Hz. The sub out was at 8.19V peak for this scene. I lined up the Dragon Crash waveforms from the OPPO @91MVL and the Sony at 66MVL. They look a bit different, eh? Imagine how much more strain this Sony's sub out would put on an amplifier and the drivers connected to it instead of the dynamic signal that it should have. Link to comment Share on other sites More sharing options...
maxmercy Posted February 18, 2015 Report Share Posted February 18, 2015 Oh man....that is awful. I wonder how many people bump their sub trim up and are experiencing this kind of thing instead of the whole waveform....and still call it 'awesome'. JSS Link to comment Share on other sites More sharing options...
Shredhead Posted February 18, 2015 Report Share Posted February 18, 2015 Oh man....that is awful. I wonder how many people bump their sub trim up and are experiencing this kind of thing instead of the whole waveform....and still call it 'awesome'. My money is on a shitload. At some point in the past I was probably doing the same thing. When you learn the limits of your equipment, gain structure gets easier. Link to comment Share on other sites More sharing options...
Bossobass Dave Posted February 18, 2015 Report Share Posted February 18, 2015 Sure, I'd be happy to Max. Just to show you guys how using the interface/DAW scope thing will sniff out clipping: Here are 2 waveforms of the same scene (HTTYD Dragon Crash) with the Sony AVR's subwoofer out and with the OPPO. On the Sony -MVL at 66 out of a possible 74maximum, 0dB sub trim, 5 speakers to small and x-over at 77Hz. The sub out was at 8.19V peak for this scene. I lined up the Dragon Crash waveforms from the OPPO @91MVL and the Sony at 66MVL. They look a bit different, eh? Imagine how much more strain this Sony's sub out would put on an amplifier and the drivers connected to it instead of the dynamic signal that it should have. Yeah, imagine that compressed mess hitting the sub amplifier when the sub amplifier has aggressive limiters? {{{SHUDDER}}} This reminds me of way back in Y2K +1 and +2 when I was trying to patent the ReBase Router, which I designed and paid Phil Marchand to build (and which prototype I still have), and seeing the indicator lights that told me when the low end was redirected bass and when it was LFE and seeing the clip lights light up like Christmas. I reported the results in a forum back then and mentioned how many people were most prob getting a severely clipped signal to their subs. Star Wars, AOTC was the first time I saw that most of the low end was actually in the front 3 channels and almost nothing in the LFE channel. That, I learned was encouraged by Dolby so that Pro Logic would have low end because it doesn't have an LFE channel. Most importantly, the clipping. Consumer gear doesn't have clip indicators and sub plate amps were always on the back of the subs... where no one could see them when they did have a clip indicator. Ever since then, I use outboard processor and amp with... indicator lights. Important stuff. Thanks to Max and Shreds for all the hard work on this. Link to comment Share on other sites More sharing options...
chrapladm Posted February 18, 2015 Report Share Posted February 18, 2015 Dave do you know if the sound engineer on the Seventh Son project was any good? Seems like great potential in that film but not very good reviews so far. Just seems like it COULD be a fun bass movie. But maybe another on the Maxmercy EQ list. Link to comment Share on other sites More sharing options...
MemX Posted February 18, 2015 Report Share Posted February 18, 2015 Great research on the clipping levels, all, much appreciated Link to comment Share on other sites More sharing options...
Shredhead Posted February 18, 2015 Report Share Posted February 18, 2015 I jumped the gun in post #627 with the pic of clipping. I forgot to attenuate the sub out of the Sony with a voltage divider so I wouldn't clip my soundcard's input. My soundcard has a self protecting limiter on it's input that puts a perfect looking square top on anything above ~3.2V peak. Here is a diagram of how to hook up a 10k or 20k linear or log pot on your sub output (you should do this with anything over ~2V) to attenuate the signal of your sub out for your interface or SC's input. This is the same thing as a voltage divider, only it's adjustable. Here is the real deal comparison of the OPPO and Sony. Same settings and scene as in post #627. In one of these I've circled some bizarre artifacts that seem to pop up randomly that resemble square waves with a sloped top. The pic with the rectangles points out a couple more artifacts and a few spots where the waveform seems to be offset from where it should be. I showed a part of the scene that had lower levels to point out that the scenes are lined up properly and there is even a good amount of distortion in the low level signals. I used REW's levels meter to see the difference in dB from the max peak from the dragon crash scene vs. the peak level it uses for a test tone. The sub test tone was about 25dB lower in level than the crash. I looked at SL's waterfall and tried to guess about where in the waveform it was 25dB down from reference and circled it. -My point in doing this is: If you used this AVR and set your levels with that -25dB test tone with an SPL meter, when playing a movie you would be missing all of the peak output that an unclipped preamp like the OPPO would deliver. I think most people's natural reaction to this would be to compensate by turning up the level on their sub trim (to make matters worse) or on the amp. That would feed the amp with a higher average level of compressed/clipped waveforms full of weird artifacts. I think this is dangerous to amps and drivers. Bosso makes a good point about amps with aggressive signal limiting too, squaring up the square waves and jacking the average level up even more... recipe for disaster. For anyone out there cooking drivers or popping amp fuses, it's probably worth checking your small signal stuff starting with your first analog out. Link to comment Share on other sites More sharing options...
Ricci Posted February 18, 2015 Report Share Posted February 18, 2015 One thing that escapes most people though is what amplifier is not going to be deep into clipping its outputs when sent 8+ volts? Some pro amps will handle that much voltage without clipping the input stage, but you'd have to set the input attenuators to almost minimum to get the output stage to not be heavily clipping itself. Yet some of the guys out there can't seem to get enough voltage to get their amps to work?...If you can't get everything out of your amplifiers with a clean 4 volts, which every legit AVR test I've seen indicates is available from the SW jack on nearly any AVR, I don't know what to tell you. The problem with plate amps gets much worse. The gain on most of those I've seen is so hot it is ridiculous. Most of them seem to only need 1 volt or so at midway on the dial or even less. I watched WOTW at REF with the subs +12dB and it sounded stellar! No clipping or bad noises or anything! Yeah right... Thanks for the information Shred...Your post popped up when I posted mine. Are you sure that the settings for the Oppo and the Sony were similar? Something seems off. The waveforms don't appear to be close at all. Not even the general shape in some of the pics. It almost seems as if one or the other has extra channels mixed in or content that the other one is not seeing also. Since the low level signals also seem to have evidence of artifacts or clipping this indicates that the issue is not in the analog output stage or due to a voltage limitation most likely. Link to comment Share on other sites More sharing options...
Shredhead Posted February 18, 2015 Report Share Posted February 18, 2015 The Sony's x-over was at 77Hz (the only choice) not 100Hz like the OPPO was. Everything else was set the same. Receiver's are extremely complicated beasts and there is a lot going on in one of those boxes. Who knows how it is processing the digital side of things compared to the OPPO or if the design of that side of things is flawed in the first place. All I can do is give it the same source material and record what comes out. My main focus was on the integrity of the waveform and the voltage level. Link to comment Share on other sites More sharing options...
MKtheater Posted February 19, 2015 Report Share Posted February 19, 2015 What sony is that? Link to comment Share on other sites More sharing options...
Shredhead Posted February 19, 2015 Report Share Posted February 19, 2015 STR-DE597 Link to comment Share on other sites More sharing options...
BeastAudio Posted February 20, 2015 Report Share Posted February 20, 2015 Great info since the last time I checked in. I worked a bit with Wayne Pflughapft or however it is spelled when working with his most recent doc involving gain structure. While you didn't test a D&M project, my findings are that the voltage out on most Denon and Marantz units are somewhere between the onk and the sony. Just through my own measurements and tests, a decent area to start out with the SW trims was between -10 and -7-8 and go from there. It gave a healthy voltage out on my 4311, where you wouldn't be at extremes on any amp gain pot, but usually around the midpoint, to get to a "somewhat" hot subwoofer chain, that kept gains in decent check with no clipping. I never kept one component long enough in the chain to really get it perfectly dialed in, but this was a good point to start from as amps and processors changed. I am still right around the same area actually. Link to comment Share on other sites More sharing options...
Bossobass Dave Posted February 21, 2015 Report Share Posted February 21, 2015 One thing that escapes most people though is what amplifier is not going to be deep into clipping its outputs when sent 8+ volts? Some pro amps will handle that much voltage without clipping the input stage, but you'd have to set the input attenuators to almost minimum to get the output stage to not be heavily clipping itself. Yet some of the guys out there can't seem to get enough voltage to get their amps to work?...If you can't get everything out of your amplifiers with a clean 4 volts, which every legit AVR test I've seen indicates is available from the SW jack on nearly any AVR, I don't know what to tell you. The problem with plate amps gets much worse. The gain on most of those I've seen is so hot it is ridiculous. Most of them seem to only need 1 volt or so at midway on the dial or even less. I watched WOTW at REF with the subs +12dB and it sounded stellar! No clipping or bad noises or anything! Yeah right... I loved this post. Over the years, this is my #1 peeve. You clip the shit out of the input signal by setting the SW trim at +12dB, filter out 3 octaves with an oppressive limiter scheme that squashes the reality out of your response because your amplifier is woefully underpowered for the task and your driver is about 40 liters short on displacement capability and then proudly report how your sub handled WOTW with no problems. It's gone on for so long that nothing is gonna stop it. It's maddening that people who design and build a system that's a minimum required to accurately reproduce the content with some headroom are called bassheads, bass maniacs, crazies, etc. It's like saying Oswald obviously didn't act alone and being called a conspiracy nut. Link to comment Share on other sites More sharing options...
Madaeel Posted February 23, 2015 Author Report Share Posted February 23, 2015 Gotcha. I actually listen at night after the wife is asleep with just the nearfield on as the farfield 8 travel right up the exterior wall and shake her out of bed...two floors up. I have full intentions of messing around a good bit this weekend, along with EQing the nearfield a little more as well as tweaking the LT on the fronts. I will do new measurements of the effect of the nearfield vs farfield and everything in between. FWIW, here was my old EQ setup, looking at the green close mic response and the EQ to bring that to flat which is the gold trace. This was with the mic about 12 inches from the cone of one of the front SI 18's And then this was what that EQ looked like measured at the MLP. Whoa, nice house curve.... The other flatter trace is the close mic EQ'd response, so you see the gain from the room as the mic gets further from the sub. My attempts will be to get the response of the nearfields to similar, we shall see how it goes. Dude, anytime you want to check it out, I would love to host. Perhaps you, Dave, and Paul can all come up this way for one day, and I come down there for the other would make for pretty fun weekend to say the least! Hey Brandon just wanted to say I'll def take you up on this offer when I head down to see Dave whenever it warms up some. Also I'm gonna try the entire Raptor system nearfield and see what difference it makes. I just need to be careful with the boost. I already ordered some 10awg wire so I just need Ethan to help me move them behind the couch then. I'm curious to try some scenes I know have ULF in them that I can barely feel now. I'll be sure to post the FR and some Speclab graphs. Link to comment Share on other sites More sharing options...
BeastAudio Posted February 24, 2015 Report Share Posted February 24, 2015 Man, an entire Raptor system nearfield is outlandish! I love it! That will be interesting to see, but if nearfield is in the middle of the room, you won't see a response similar to what you are getting now. It will be more tactile for sure, but different. Will be interested to hear your impressions, but I wouldn't be surprised if you moved them back to their current spot and looked towards some crowsons or additional subs to satisfy your nearfield/tactile needs. Even then, nearfield can very easily overtake your other sub's response, so finesse is the name of the game here... Link to comment Share on other sites More sharing options...
Madaeel Posted February 24, 2015 Author Report Share Posted February 24, 2015 Yah this is strictly for experiment sakes. No way I'm keeping those beasts in the middle of the room. I'm just curious on known scenes that are strictly below 10hz can I feel the ULF. It wont take but a couple minutes to move them with two people it's just adjusting the FR with eq I need to be careful with. I also need a MiniDSP... I will say IF I can feel the ULF I will go your route and do some high displacement drivers near field. Since Dave doesn't make the Raptors in white idk what I'll use. Maybe four 24's in white cabs. Btw I think buttkickers or whatever people call them are the devil. No way I'm replacing actual bass waves with those. After experiencing true ULF in Dave's room I know it's possible. Plus it's against my religion to do so. Link to comment Share on other sites More sharing options...
Bossobass Dave Posted February 25, 2015 Report Share Posted February 25, 2015 As I said before, it's common sense. I can replicate a GP measurement by placing the mic within an inch or so, or... near field to the dust cap. The closer you get, the closer the response reverts to the GP response. Room gain gets masked. It's like the old days when I stood in front of the PA stack at a large venue concert. More tactile, yes, more accurate, no. Here's a 1/2 dozen caps from FURY. As Max noted, VERY clean production on this soundtrack. Sound design/Mix and Supervisor for this one by Paul N.J. Ottosson. His credits include Hurt Locker and Battle:LA. You should pick up a copy because clean is better appreciated when you're up close. Link to comment Share on other sites More sharing options...
Madaeel Posted February 25, 2015 Author Report Share Posted February 25, 2015 Huh Fury actually digs deep in some of those scenes. I def gotta watch that. Yah I had a friend from work stop by and I had the SEQSS on 6db boost and 8db hot instead of my normal 10-15. It sounded great and still shook the hell outta the couch. Honestly I couldn't tell the difference between that and with it set to 10db boost and the level hotter. I'll definitely check out some more movies and lower the sub level. Right now I have it set to 5db hot. To go lower I'll have to turn down the gain on the amp. I'm just curious if I can feel the lows from the Raptors up close but I won't keep them there. Any chance of making white BB's? Sure would be pretty. Link to comment Share on other sites More sharing options...
Shredhead Posted February 25, 2015 Report Share Posted February 25, 2015 finesse is the name of the game here... No doubt B, that seems to always be the game. What are you using for EQ on your near-field? And when we hang again, we will have to crank a little metal. Link to comment Share on other sites More sharing options...
BeastAudio Posted February 25, 2015 Report Share Posted February 25, 2015 No doubt B, that seems to always be the game. What are you using for EQ on your near-field? And when we hang again, we will have to crank a little metal. Always down for that man Currently I have no EQ on my nearfield. It looks like a snow-day might be upon us tomorrow, so hopefully I can get in the theater for some much needed work. I honestly keep the level of the near field low enough it doesn't affect the overall FR, just simply adds a nice tactile effect to what the main subs are doing. They are properly time aligned and all that, but I still have much more experimenting to do with it. Link to comment Share on other sites More sharing options...
Bossobass Dave Posted February 25, 2015 Report Share Posted February 25, 2015 No white BBs in the works, sorry. We could always build a white box for a one-off. Actually, if I ever get a response from the manufacturer, we plan to look into the whole sound pressure vs acoustic particle velocity phenom. If there is sufficient evidence and good results, I'll def design a near field sub accordingly. IMO, it won't have to be DO 15s or 18s, though, and there will be a formula for level vs distance for matching output with far field. Link to comment Share on other sites More sharing options...
Madaeel Posted February 25, 2015 Author Report Share Posted February 25, 2015 Don't tease me man! A white BB would be.....gorgeous! I'm thinking white cabs with the glass top would be perfect. I was seriously thinking two BB's behind the couch would look amazing and give me the added tactile feeling I crave like a fiend. I would just need to buy another 14k. I can make space in my rack. Actually now that I think of it I could always take the Minka downstairs.....I'll have to wait for her to leave or else that'd be a beating. Hold on she literally just told me "don't touch my fucking subwoofer". Wow. Ok Raptors near field it is. Link to comment Share on other sites More sharing options...
Madaeel Posted February 25, 2015 Author Report Share Posted February 25, 2015 Actually, if I ever get a response from the manufacturer, we plan to look into the whole sound pressure vs acoustic particle velocity phenom. If there is sufficient evidence and good results, I'll def design a near field sub accordingly. IMO, it won't have to be DO 15s or 18s, though, and there will be a formula for level vs distance for matching output with far field. That would be amazing. If you build em put me down for two so I can do 15db hot near field. Link to comment Share on other sites More sharing options...
Bossobass Dave Posted February 25, 2015 Report Share Posted February 25, 2015 Don't tease me man! A white BB would be.....gorgeous! I'm thinking white cabs with the glass top would be perfect. I was seriously thinking two BB's behind the couch would look amazing and give me the added tactile feeling I crave like a fiend. I would just need to buy another 14k. I can make space in my rack. Actually now that I think of it I could always take the Minka downstairs.....I'll have to wait for her to leave or else that'd be a beating. Hold on she literally just told me "don't touch my fucking subwoofer". Wow. Ok Raptors near field it is. Man, I didn't think of that either. That would be the easy move to see what's what with near field, no? Link to comment Share on other sites More sharing options...
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