Quote: |
I have heard very few acoustician's and other manufacturers criticize this approach ... Ethan, what do you think about this stuff? |
jetbase wrote on Tue, 29 May 2007 21:07 |
How does the positioning of the monitors (eg. near a boundary) affect the frequency response & treatment in this case? What I mean is, if the room is ok but you need to have the monitors (assuming free standing) near a front or side wall, which I would assume would increase low frequencies, should you flatten the response by eq or by acoustic treatment? |
Quote: |
there are some DSP based systems that can make a marked improvement in performance at the listening position |
Quote: |
The most significant of these in the bottom octaves, which we all know are the most difficult to deal with using mechanical treatment. |
Quote: |
should you flatten the response by eq or by acoustic treatment? |
Quote: |
The problem is that "listening position" IMO needs to encompass both ears at the same time, and in a small room DSP can't do even that. |
jimmyjazz wrote on Wed, 30 May 2007 16:10 |
Mark, how would you describe the effects of DSP correction at room locations OTHER than the one you corrected for? Did the rest of the room get subjectively "worse"? |
Bill Mueller wrote on Wed, 30 May 2007 16:29 |
Mark, I think we might have met many years ago. I was with Sheffield, engineering a remote for the Boston Pops and we bought a couple of reels of Sony Dash 1/2" at Soundmirror. Nice place. |
Quote: |
My argument is that creating linearity in a studio monitoring system by distorting the source signal, instead of correcting the actual problem of acoustics, yields a non linear mix product, when the engineer things he/she is creating a linear mix product. In addition, the engineer no longer knows WHY they are making their mix decisions, on the basis of the actual 2 buss signal or the room acoustics. |
Quote: |
I would also add that I instigated this thread because the issue bothers me. So far, I can find no flaw in Ethan's logic, whether or not he has a product to sell. I have also asked others like yourself to weight in because if the laws of physics (or studio design) have changed lately, I would like to know about it. Best Regards, Bill |
Quote: |
By the looks of it, the Audyssey is nothing more than an an automatic parametric EQ. I agree whole heartedly that static EQ is not a solution for room correction. What I am talking about is active room correction like the Sigtech AEC and TacT RCS. |
Quote: |
These devices apply a time delayed correction signal that can reduce the levels of early reflections at the listening position by as much as 18 dB. Also, rather than reduce the size of the sweet spot, with proper setup, it increases the size of the sweet spot appreciably. |
Quote: |
With any acoustic measurement system, measuring from a single point is space will not give any perspective on the real issues at hand. |
Quote: |
It just worries me when you make blanket statements that there is no such thing as DSP room correction, especially when you have a vested interest in promoting a product. |
Quote: |
So far, I can find no flaw in Ethan's logic, whether or not he has a product to sell. I have also asked others like yourself to weight in because if the laws of physics (or studio design) have changed lately, I would like to know about it. |
Mark Donahue wrote on Wed, 30 May 2007 17:33 | ||
Hey Bill, I remember that. Wasn't that a Pops TV thing? |
Quote: |
I don't follow your logic. The correction systems are part of the monitoring chain. The way that I think about it is that you are trying to remove the variations in acoustics from the equation. It doesn't matter if you are using mechanical acoustic treatment or DSP. If you boost the subwoofer by 10 db, your printed mixes will tend to be bass shy. If you have huge valleys and peaks in room response, your mixes will tend to have the corresponding opposite peaks and valleys. Back when NS-10's were all the rage, I could tell by the mixes that they were mixed on NS-10's by the sound of the master. However, if you create a listening environment that yields consistent and even response, your mixes will translate. |
franman wrote on Thu, 31 May 2007 23:33 |
1. We use room eq fairly regularly... let's face it, a crossover is a series of equaliziers. We often take up three or four bands of eq to 'create' a proper cross over slope for our systems, so technically a factory tested setup on Griffin monitors alreayd is "eq'd"... |
Quote: |
2. We agree whole heartedly that equalizing for comb filtering caused by early reflections is a loosing cause.. |
Quote: |
3. Larger boundary and modal issues that cover a reasonably large range (1-2 feet) around the mix positions are candidates for cut only eq.... You can absolutely lower modal ringing as it is percieved at the mix position by lowering the output from the system (and yes, changing the linearity of the system) with some cut eq// Remember the "System" is comprised of the wire, amplifiers, crossover, loudspeakers AND the room!! |
Quote: |
Sometimes there are valid and practical fixes that can be made to improve a control room's response. Sometimes there are not! this is just a fact of space available, budget, practical construction variables and client resistance... |
Quote: |
4. I am NOT a fan of room equalization, but given the fact that modern DSP controller units like the BSS Soundweb London, DBX Driverack and Lake processors all offer crossover functions, micro delay adjustments, multiple bands of eq and limting, we feel that if we can tweek the system "in place" to make it more linear as a COMPLETE system (and the mix position) with reasonable restraints, then we will do it. The limits of how much eq and how it is applied are all based on experience and common sense with understanding of what is CAUSING some of the non-linearity in the final response. Remember, it is the acoustic response that the engineer hears that he bases his mix decisions on!! |
Quote: |
so, I guess I fall in the middle hear. Ideally I'd prefer to do NO room eq, but the nature of (our) crossover designs includes so much "eq" to make a proper acoustic crossover response, that it's already in there... Lars can speak to this more elegantly that I, but he and I typically agree on what mix position anomolies are candidates for eq and what ones are not. As far as the Auto Adjusting DSP systems from JBL , Genelec and others, we have some limited experience with them. What I can tell you is that the last Genelec 8050D surround system we setup in a room of our design, sounded more 'musical' than any I've setup recently AFTER the autocal... so, subjectively I have to say I like what it did. The autocal does very little above 2K (I think) and it mostly 'corrects' lower octave issues. You can also make multiple measurements at multiple locations and 'average' them if you feel this is valid... |
Quote: |
"accurate respone anywhere"??? no way... not possible IMHO... I just believe there is room for this technology to work hand in hand with proper trapping, reflection control and room design. There is ABSOLUTELY no substitute for proper room proportions, speaker placement and lots of broadband trapping!! that's my soapbox and has been for years!! I'll be talking about this next week at the TOC (I'm covering easy DIY basetrap designs for the masses)... and we believe you can never have too much of it!! |
Quote: |
Anyway, there it is, I've chimed in and probably disagreed with many (on the eq/DSP issue) but this is our real world experience along with the theoretical considerations weighed in there.... I don't know, but I think there is room for the technology... |