Quote:
Originally Posted by
amirm /forum/post/21952006
Yes, I completely ignore it.
So does Dr. Toole. What on earth are you going to do after you find out you have cabinet diffraction? Cry or take a file and start rounding the corners?
As I said, buy good speakers. If you start with bad ones, you are on the wrong course already.
so you believe the only sources of edge diffraction within an acoustical space are from the cabinet? what about mounting surfaces if soffit mounting? or other nearby objects within the room/living room?
oh, and toole does discuss the ETC as he has with Nyal Mellor and Jeff Hedback --- you can view their paper here: Nyal Mellor, Acoustic Frontiers LLC & Jeff Hedback,
http://blog.acousticfrontiers.com/st...ist.%20Rms.pdf
you'll also notice some example rooms at the bottom - eg, a "typical living room" that has been treated without simply relying on existing furniture within the room to achieve the desired acoustical response.
they both have pretty extensive backgrounds in room design and acoustics. curious how many rooms you've designed for your customers?
and while we're on the subject, do you have any issues with how the Erskine Group designs their rooms and the treatment they place at sidewalls? kromkamp does the same (currently absorption; soon to be absorption+diffuser combo). they seem to prefer treatments at the sidewalls. erskine's has quite a portfolio and documentation of highly pleased customers. hmm, why would *he* treat the sidewalls?
Quote:
Originally Posted by amirm /forum/post/21952006
I have provided that reference multiple times. It even includes the answer to your question above which I have quoted here and in the other thread. here it is again. AES paper, A New Reference Listening Room For Consumer, Professional and Automotive Audio Research", Sean E. Olive (2009)
no, i asked YOU how YOU utilize the rt60 to decide how much, what types, and where to place measurements. why do you keep referring to other people's work? why can't you speak for yourself based on your past experiences? it should be a relatively easy solution and workflow for you to put forth. why must you constantly rely on the work of others?
Quote:
Originally Posted by amirm /forum/post/21952006
Sure. It is very easy to do. I have been in that room a number of times and it is very easy to duplicate. All is extremely well documented and logical.
i think that harman room is too much of a padded cell to be honest. there are some good % of surfaces coated with thick broadband absorption. padded-cell variety. no thanks. and why such sparse utilization of RPG diffusers in the harman room? why not coat more of the flat surfaces with diffusers? if harman is designing a custom room, why wouldn't they design their own diffusers based on their own bandwidth and sq area requirements? why rely on conventional off the shelf products for a custom room? are your company's reference room diffusers designed from scratch - custom for the room? or are they purchased/off-the-shelf products? i see some auralex and RPG products there - care to elaborate?
Quote:
Originally Posted by amirm /forum/post/21952006
I explained it in my summary post and Dr. Toole is your ultimate reference.
ultimate reference? nah, no where near enough meat in his publications, book, etc to be considered an ultimate reference. i do think you have a man-crush on him, though...
Quote:
Originally Posted by amirm /forum/post/21952006
As I said, no. You made such wrong commentary in the first response that the rest did not merit a read. Anyone who sees those measurements and thinks that the room impact is not in low frequencies and that we must fix that first, is honestly barking at the wrong tree. While you go after figuring out the diffraction in speaker cabinets, the rest of us are after fixing 40 db frequency response variations with simple yet powerful techniques such as multiple subs, SFM, EQ, appropriate speaker selection.
no one has ever contested that LF issues is not a priority. and what does the modal region have to do with other important factors like: localization, imaging, spaciousness, envelopment? you insist it is all based on speaker selection. are good room and good speaker mutually exclusive? can a good speaker cure the inherent issues in ANY room?
tell me, how many more subs can the OP fit in his living room? does he have the capability to place them in the ideal locations? or does furniture arrangement dictate sub placement (eg, typical living room design constraints).
Quote:
Originally Posted by
amirm /forum/post/21952006
Wouldn't be my first worry. I would first try to fix the bass. He is a movie guy with multi-channel sound so by your own statement, your NE, etc. room models don't apply. And I am pretty sure he is not putting 4 foot diffusers on the walls
.
sidestepping the question. i dont care what "priority" order you assign tasks - the window at the left sidewall reflection point is going to alter the spectral content and break symmetry with the right wall. are you saying this isn't a priority? where would you put solving this issue in the priority chain? once he has LF addressed, how would YOU then go about addressing this?
and you can mock 4ft diffusers all you want - that's your ignorance.
sound has size and my recommendations do not change physics. if you want an object to be 'seen' by a particular wavelength (frequency), then the object (reflector, absorber, diffuser) needs to be large with respect to wavelength in order to be effective. this is physics 101. don't tell me you didn't learn such information in your 'two-day become-an-expert-in-acoustics' training class?
Quote:
Originally Posted by amirm /forum/post/21952006
I would ask him to orient his speakers toward the couch so that he is hearing more of the on-axis response.
so that will eliminate the colored reflection due to the window? what's the off-axis response of his speaker? turning the speakers is going to solve this problem you say?
Quote:
Originally Posted by amirm /forum/post/21952006
I would ask him to run the tests I suggested for how reflective his room is. If it is too reflective, then he should put more furniture and such in his room to tame that.
what tests would you use for this? how do you determine which surfaces are too reflective and which are not? what is YOUR work flow?
Quote:
Originally Posted by amirm /forum/post/21952006
And that is the aim in an anechoic chamber. We want to measure a speaker with a mic. If an NE room provides only the direct sound from its speaker, then it can be a replacement for an anechoic chamber. Why is it not that? Why do anechoic chambers have floors that are that way as with front wall? Why not stick a table there and put the mic above it?
it is not a replacement for an anechoic chamber unless the listener-room response is anechoic as well --- which it is not. didn't i just explain this to you? have you already slipped back into misunderstanding what 'perspective' means?
anechoic chambers don't have a design requirement to have an anechoic response at one location (listening position) like with NER. the requirement is to be anechoic from any source-receiver location. do you not understand customer design requirements?
Quote:
Originally Posted by amirm /forum/post/21952006
From your statements per above. If the ear is only hearing the speaker and no reflections, then I can replace it with a mic and perform anechoic measurements of the speaker.
sidestepping again --- do you or do you not have any experience tracking vocals? building vocal booths? working with singers and what THEY prefer? any experience at all?