Originally Posted by jevansoh
First I wish to thank you for responding in a civilized manor and without getting defensive.
I've read a lot of text books in my time, I've spent a lot of time on forums, and I've been involved in different aspects of business for awhile now, but no matter how much one reads and learns, experience counts the most in my opinion.
Based on what you stated in the text above, it seems as though I may have less than 10% of your real world experience at this point in my life and career, however, I do believe strongly in continuing education, gaining more experience both for knowledge sake and in that it means my bottom line continues to grow (I have work).
I'm sure over time my ideals may change a bit as I continue to learn and grow and I hope I never become a crotchety old man stuck in his ways.
But for now, I only have the education and experience I've gained so far to go on and have to respectfully continue to disagree with just a few of your ideals regarding the targets for 2-channel audio expressed previously.
I do respect where you're coming from and hope you understand that while I have some different viewpoints on certain aspects of what you believe, I don't know that either of us could say the other is "wrong" as all it boils down to is what make the customer happy.
For this thread I want to introduce folks to standard ways of doing things that aren't challenged by most and even if certain goals aren't totally met by each person, I know that nothing I'm teaching is going to make their rooms sound worse. There will always be room for improvement, but at least I'm doing no harm.
I'm sure through your experience you have found numerous reasons to come up with your own way of doing things and go down your own path, so to speak. At this point though, with my level of experience and knowledge, I simply feel more comfortable in teaching what I've learned and know works and for the most part is widely undisputed.
So I guess what I'm saying is, welcome. There is room for many different theories on what is "right" but the most important thing in my opinion is for one to decide what that path is going to be and follow it. If goals are set and worked towards to achieve them by passionate audiophiles, they will simply learn a lot along the way and enjoy their systems that much more and that enjoyment and knowledge gained will last a lifetime.
I'm glad to learn there is a typo in your document as quite frankly I mainly took issue with two of your points, one being a +/- 10db window is a "goal" and is acceptable, however, now realizing that is supposed to read +/- 5db I wholeheartedly concur. We are on the same page.
Where we remain opposed however is in regards to reflections. I never once stated all reflections are bad. In fact, I believe they are absolutely necessary.
I do believe that high gain early reflections are absolutely detrimental. I believe they cause smearing and muddiness as I've heard it myself. I also believe that nobody likes to listen in rooms approaching anechoic conditions therefore reflections after a certain termination point are necessary and they create the psychoacoustic effect of making the room seem larger than it is. Therefore, reflections become necessary, after a certain point and to a point, just not random uncontrolled reflections.
When creating a room that has a small period (12-25ms depending on the size of the room, budget, goals regarding focus on 2-channel or HT, etc) of low gain early specular reflections around -20db terminated by a high gain (around -12db or more) specular reflection and followed by a diffuse and infinitely decaying rate of further reflection, the direct sound will be heard, clear, no smearing or muddiness, and the room will sound spacious and live.
There are of course many other factors that if are not addressed will cause this effect to collapse, however, and I believe we are in agreement on most of them.
I don't think the goals for 2-channel and HT are all that different. Yes, there are differences, but let's face it, most rooms are multi-purpose including dedicated rooms as most folks (the folks reading this thread at least) don't have a dedicated 2-channel room and a dedicated HT).
I disagree that a room with an average 200ms decay time will not sound very dry, however. Maybe "dead" was a bit harsh, but 200ms sounds quite dry and you can't just fix it by adding a ton of diffusers and diffusers, by nature, also absorb and will reduce that further, plus too many diffusers, if not placed surgically and strategically in the room will cause other problems such as interfering with the early reflections you worked so hard to tame, lobing issues depending on the design, etc. If the diffusers are broadband then the room has to be large enough, too. So just placing a ton of diffusers all around a room with a 200ms decay time is NOT an answer IMHO.
As for the rest, we're pretty much on the same page.
I like to target +/- 5db with no EQ - full band. +/- 3db with EQ - full band.
Depending on the size of the room I like to target between 300-500ms and quite honestly will accept 250ms in smaller harder to control rooms and seldom reach much over 400ms in all but the largest of rooms. The target is always 10% but I'll be the first to admit I've yet to achieve it. 20% is more reasonable and I cannot disagree with your 25% recommendation fully, however, I do believe that should be the absolute limit.
With those targets, it's not necessary to state that the bass can decay slower than the specular region other than to say it is common for the lower frequency range to be the hardest to tame and it will take the most skill, time, and budget to get in line without affecting the specular region negatively. Why create two different targets then also state you need to keep the full band decay time within 25% relative?
So again, we may belong to some of the same clubs, pay membership dues to some of the same places, and have similar ideals with but a few differences, but one thing is sure and that is our experience differs by a great amount with you simply having more of it.
I hope we can speak again and would like to get to know you better.
I hope you can at least see that there is room for my philosophy and yours, and that the important thing for folks trying to learn is that they understand the differences, pick a model (yours, mine, or other) and start working towards it to accomplish true audio nirvana!
I hope our paths will cross again sometime, Nyal.