Amir, I just watched your video (twice). Thank you for an informative and honest tutorial. I have two questions:Per popular demand, I recorded a long (1 hour) video on how to read speaker measurements but also, the underlying research (and physics) that mandate some of those concepts. Also covered is equalization and listening tests (briefly). As usual, my videos are "one take" directly recorded and uploaded (and in this case, with no reharsal). So please take it easy as far as critiquing it in that regard.
A personal note: as you all know, I don't allow advertising in my videos, nor do I pester people to subscribe, give likes, etc. in the video. Alas, it seems some out there are keeping score on popularity of my content as proof point of whether their audio videos are more correct than mine. So let's even the playground and subscribe to my channel if you have not before. Click on this link to go to my youtube channel (youtube.com/@audiosciencereview) and do that. Appreciate it in advance.
Klippel simply computes the far-field model of the speaker. The early reflection is a summary report based on CEA-2034 which gives a formula for half a dozen reflections. This is based on research into a number of listening rooms by Alan Devantier. It is a statistical model and doesn't match any one specific room. I can dig up the AES paper if you are interested in the research.1. What is the far field simulation Klippel is performing to produce early reflections? These are fully dependent on driver height, speaker's distance to walls and room dimensions all of which will vary wildly from room to room. These must be based on a certain room size so treatment based on merely these graphs didn't make sense to me. I also cannot see the first cancellation and the first peak at double that frequency in any of these early reflection graphs.
The volume of my room is very large (open space with 25+ feet ceilings) so my room modes are not severe. But they are surely there and would need correction for best response depending on the speaker. For my main system where I test consumer speakers, I routinely dial a PEQ at 105 Hz for this purpose (I note it in the reviews). I don't usually bother for near-field.2. You correctly EQ for speaker resonances (and btw that 590hz peak is the box reflection IMO, they have not put enough insulation material inside the box) but doesn't correct for any of the room modes which are the causes of the major distortions in frequency magnitude. Is that because your room is so heavily treated that you don't even have peaks (and dips) below 200Hz?
Thank you and no need to go that deep . I guess they show how much a speaker's directivity will contribute to early reflections and one can derive the rest from his own room dimensions.Klippel simply computes the far-field model of the speaker. The early reflection is a summary report based on CEA-2034 which gives a formula for half a dozen reflections. This is based on research into a number of listening rooms by Alan Devantier. It is a statistical model and doesn't match any one specific room. I can dig up the AES paper if you are interested in the research.
I couldn't agree more on mandatory bass EQ and I start understanding your room size from the 105Hz peak! I could get rid of also your 52hz dip by a VBA filter if you're interestedThe volume of my room is very large (open space with 25+ feet ceilings) so my room modes are not severe. But they are surely there and would need correction for best response depending on the speaker. For my main system where I test consumer speakers, I routinely dial a PEQ at 105 Hz for this purpose (I note it in the reviews). I don't usually bother for near-field.
Net, net, EQ for bass is mandatory in all situations. Even rooms that are heavily treated still have modes.
There is a portable Dayton measurement mic and an app called Audiotools that can do similar stuff like REW.Is there any portable tools like this so we can bring it to audio expo such as Axpona?
I for once used the likes/dislikes ratio as the first filter of videosInternet...
Where "popularity" gives you more credibility than the actual truth.
Didn't watch the video yet, but I'm sure it's comprehensive content. Glad to see you back on YT!
The comments come from people typing unfiltered and unreflected what they feel. Most people don't know the difference between thinking and feeling.I forgot that (extremely low) trolling quality in YT comments...
Amir doesn't exactly say step response is useless. He says such a signal doesn't exist in real World and the dynamics of the drivers to recover (in your words) are irrelevant. However, he mentioned the time delay between the tweeter and midbass driver the step response illustrates. Minimizing this delay in speaker design is important for heightened sound stage. Some high-end speakers even come with adjustable tweeter, midbass angles and lots of instructions to set it up correctly for the actual LP distance.Great Video @amirm - if you do decide to do a talk at a future AXpona or similar event - a cut down version of this would surely go down well (with most open minded audiophiles) there
But a quick question, and I know you mentioned you think the step response is useless - but I am still curious as logically it would seem to me that an 'ideal' woofer would have a faster step response to be able to handle very 'fast' music, e.g. play something at 90db @ 200hz followed say 1 millisecond's later by being told to play something a 70db @ 500hz - if the woofer is still 'recovering' in time from playing the 200hz tone surely that would interfer with playing the 500hz tone correctly?