Home Theater Forum and Systems banner

1 - 20 of 66 Posts

·
Registered
Joined
·
348 Posts
Discussion Starter #1
After now close to 10 hours of tweaking (from getting it last Wed.) and playing with the pro eq and reverb 3d features I started to really explore the difference MCACC was providing when measuring my bi-polar high freq drivers. I noticed a little something on the 3d graph and started thinking maybe mcacc was really having a hayday with those highs. I will qualify: After constant calibrations and re-measuring using the 30-50ms vs. 20-40ms schemes my listening experiences were obvious but nothing drastic per se', but now when I removed the rear firing matched tweets the whole deal changed and high freqs were very different and measured better after viewing the eq sliders. The 20-40ms calibration was very encompassing and really thick and dimensional but I seemed to lack width. Again, the only thing I tried here was same 20-40ms calibration just minus the rear firing tweet. So, I re-did it this time with the suggested 30-50ms calibration and stage width was as big as my room, still had crazy depth, and just bigger. So, according to my surround reverb graphs I get that efficiency peak around 90ms and measure almost 5ft from listening position with mains almost 13ft. So my fellow room correction smart ones, can my rear firing tweet that I no longer use have made that much of a difference with all else the same? :nerd:


Brian in Bakersfield...
 

·
Premium Member
Joined
·
8,367 Posts
MCACC is very sensitive to any changes in speaker position and presumably any changes in the number of drivers..
Even moving the surrounds a few inches forward or back can change things quite dramatically..particularly in respect of reverberation settings..
I presume the bi-polar's you're speaking about are the surrounds? That being the case, How close to the back wall are the surrounds? Obviously if they are fairly close then removing the rear firing tweeter is going to make a significant difference, which MCACC will pick up..
I also have my delay set at 30-50ms. and found that to be the best setting..
 

·
Registered
Joined
·
348 Posts
Discussion Starter #3
Thanks for your response, the rear firing matched tweets were on my front towers. With my Yamaha YPAO it seemed to work and gave a super deep soundstage but, with a more advanced calibration setup in the mcacc i could really see some things it was trying to correct and the difference after removing rear tweets was very clear and better with a more exact and correct 3D response graph. The clarity which was always awesome just got a whole lot better with still a very deep sound stage after removing them. I have over 20 hours of advanced MCACC time now and enjoy the parameters at my finger tips. I've consulted other Audio Engineers with my data from adv mcacc and my chosen calibration time is now the 0-20ms setting using the ProEQ per some book knowledge and also some critical listening sessions. I honestly could spend all day messing with it!


Brian in Bakersfield...
 

·
Premium Member
Joined
·
8,367 Posts
To use 0-20ms. you must have a very flat graph on the Reverb View, with virtually no slope at the beginning!.Is this what you're seeing?
Even though my slope is quite rapid and could easily use 10-20ms in compliance with MCACC recommendations, but I've found that I get better overall 3D type sound if I select the longer delay..30-50ms..
Of course all this depends on the size of your room and the acoustics of the room..

I know what you mean about messing with it all day! I've lost count the number of times I've tweaked with the settings..just to get that bit more out of the system! :D
 

·
Registered
Joined
·
348 Posts
Discussion Starter #5
Yep its a rapid curve: 1K and 2K flatline at 10ms. 125hz and 16K at 20ms very specifically and the rest right close to 20ms and maybe a little after. It sounds very sharp, clear with surround effects being awesome and the 30-50ms did completely surround me with a very 3D experience. Just interesting how differently the width and depth can be messed with and still have surround signal strength.
 

·
Premium Member
Joined
·
8,367 Posts
Yep its a rapid curve: 1K and 2K flatline at 10ms.
That is very good! My flat line doesn't begin until about 20ms., but all the frequencies are tightly bunched together..
What I found when using the shorter delay times was that the front sound (whilst being quite clear) didn't have much projection and the surrounds seemed more subdued..But of course each situation is different..
 

·
Registered
Joined
·
348 Posts
Discussion Starter #7
I will probably re-set it for the next choice up on the scale and listen for a while. I just wish I could post a graph. Thanks for your interest and I know sometimes my excitement gets in the way and I may not always be clear. I have it set up also as THX but have to reduce the crossover from 80hz to 50hz because of my first standing wave of 74hz. We need to create an advanced mcacc support group :nerd:
 

·
Premium Member
Joined
·
8,367 Posts
I have it set up also as THX but have to reduce the crossover from 80hz to 50hz because of my first standing wave of 74hz.
Likewise..I have THX selected on mine also, but have crossover at 80hz. My first standing wave is at about 45hz.!

We need to create an advanced mcacc support group :nerd:
Yes..It has surprised me that there has been very few postings on MCACC here! Over on the unnamed forum there 75 pages on the subject! :scratch:
 

·
Registered
Joined
·
348 Posts
Discussion Starter #9
45hz???? hmmm, my minds a wondering what kind of room it takes to read that. I'm trying to reverse engineer that in my head, i'm trying to figure why i need boost at 4K currently. Tomorrow morning I will be running it again with the expert version only and listen, I will have the house to myself for a few before I go to work. It's funny how I will tweak on it thinking its awesome then re-run auto mcacc with "keep sp" and it sounds just as great or better. Guess I'm not nailing it as much as I think but for me that's the fun.
 

·
Premium Member
Joined
·
8,367 Posts
The 45hz. standing wave is below the MCACC EQ range of adjustments and also below the acoustic absorbers ability to have any affect in the room..Hence the peak..
The second harmonic of 90hz. is still outside the EQ's range but does get some dampening from the absorbers..and the third harmonic is absorbed completely..giving a relatively flat response from about 60hz. on..

i'm trying to figure why i need boost at 4K currently.
With my room set up I find I have to do the opposite..ie cut the 4K. level for the fronts, but I have to boost the 4K. level for the surrounds! :dontknow: :scratch:

One problem I'm having with MCACC is that it always sets my front speakers about 4dB too high and I have to check levels with an SPL metre every time I do a calibration ..
 

·
Registered
Joined
·
348 Posts
Discussion Starter #11
Prof, I was playing today with the standing wave multi-point measurement and did 2 of the 3 spots right next to the listening position on either side and my standing waves are now as follows: 63hz, 74hz, and 96hz (before it was 74, 96, and 136hz i think). So doing all 3 positions made a dramatic quality difference in my lower response and I can explain it like listening to the lower octaves in digital vs. analog. The qualities are very different sounding and extremely defined and transformed once again the sound quality of the bass. In fact doing the 3 position standing wave measurement completely changed the sound of the 30-50ms pro eq settings as well as the 20-40ms settings. It really changed everything all over again. Man, should have done the 3 measurement locations from the start! I'm also thinking that things are breaking in well, drivers and receiver. Just seems to have loosened up and opened up. :scratch:

For those reading, this measurement is different from the multi listening location settings and deals with great detail the filters and Q used to correct standing waves in the room. :nerd:
 

·
Premium Member
Joined
·
8,367 Posts
Dr. Brian,

I did a 3 point measurement test awhile ago, with the mic placed in the left, centre and right seats..
It did make a significant difference to the sound overall..and particularly improved the sound for the left and right seats, but I didn't quite like the sound from the centre seat (where I sit) so I re ran just the centre point only again..

The 3 point measurement..for me..is worthwhile if you have people regularly sitting in the side seats..which I don't..

That's interesting that you took your measurements just a bit to the left and the right of your centre seat..I will have to try that myself..particularly since it changed your low end standing wave frequencies..

What I have found is that the placement of the mic. in the centre seat is very critical in respect of height and closeness to the back of the chair..
I can hear a difference in the reproduced sound from having the mic. a little forward from the back of the chair, to moving it slightly back closer to the back of the chair..
This changes the surround sound spread quite noticeably..That, along with the various delay adjustments makes for a lot of experimenting! :D

At the moment I have the best sound yet! I set the mic. near the back of the seat and raised just above it..I also changed the delay to 40-60ms. This seems to give the smoothest sound field from fronts to surrounds in my room..
I'll be interested to see how the 3 point measurement sounds now, following your positioning..

At the same time of all this, I'm doing some tuning on the ports of my front speakers (now that they've loosened up)..trying different densities of materials in the ports..
What fun! At least it keeps me off the streets!! :bigsmile:
 

·
Registered
Joined
·
348 Posts
Discussion Starter #13
I first made the mistake of not reading my manual :eek:lddude: because I didn't realize that the first measuring location is #2 spot, then 3, then listening location which makes total sense now. The last should be the main listening location, duh! I just am amazed at the difference with all else the same. My 30-50ms setting before 3point measurement was really thick and 3D but now the same 30-50ms is still thick but more deep and behind enclosures and more invisible. Effects from surrounds are still strong but now the soundstage is more deep than forward as before. All of this stuff is why I love and searched this product. I really stand firm with 2 technologies that cannot be argued by others, Full Frequency Phase Control and the multi point Standing Wave measuring. I have to fully agree and I too have messed with mic locations in relation to my ears. There are many variables at "ear" location and I have messed with mic angled slightly (very little) to going to extremes to make sure mic is flat at ear level/location. :nerd:

We seem to share some experiments, I have been messing with my fronts as well (TWW's tuned to low C) and have decoupled my top of the 2 woofers from the baffle and really stuffed with polyfill then, making sure bottom woofer is coupled to the thick baffle and re-arranged my ceiling tile placement piece for closer proximity to driver to more match internal placement in my dual sub setup. The net result was almost a 3-way sound using a 2-way crossover. I achieved more bass and removed all the polyfill from bottom woofer location too. The ceiling tile placement is also angled inside but vertical and the goal there is to control the impedance of that bottom driver to be more efficient in the lows. Crazy how ceiling tile placement for top "W" cleans the midrange being heavily stuffed, and the bottom "W" is acting more like a bass driver. Now I would like to try the fronts as "Large" with my subs at "Plus" now with all the lower octave cleaning and increased definition of a already great sound the 3 point measurement has provided.
 

·
Premium Member
Joined
·
8,367 Posts
A few set ups have found that setting speakers to LARGE and sub to PLUS has given the best results, whereas for most it's the SMALL setting with 80hz. crossover that seems to work the best..
SMALL or LARGE having no bearing of course on the actual size of the speakers..

I ran the multi point set up yesterday, with the mic. either side of the centre seat for positions 2 and 3..
The end result was very disappointing..:thumbsdown:
I checked the EQ after calibration and found that MCACC had set everything the opposite of what I had previously set!!
The frequencies from 125-500hz. were all reduced in level ( quite significantly on some frequencies) and everything above was raised in level!! Go figure! :scratchhead:
Voices sounded terrible with over emphasis on sibilance and with no body to the overall mid range..
I consequently returned everything to my previous memory..
 

·
Registered
Joined
·
348 Posts
Discussion Starter #15
I'll bring the pizza, looks like its gonna be a fun day of measuring! Interesting with the results and with your awesome room (my photos) our rooms are so way different. I'll be over in the morning...:D
 

·
Premium Member
Joined
·
8,367 Posts
Thanks Dr.Brian for the compliment on my room..

It's not a large room as you can see, but it's tuned to the best of my abilities and does a pretty good job..
With all the different size rooms and with all the inherent variations in acoustics, it's no wonder results can differ so much when tuning with MCACC!
To obtain reference levels across the fronts, I have my LCR levels at +2.5dB. and my Tripole surrounds (very inefficient speakers) at +6.5 dB.!!..That will give you some idea of how acoustically dead the room is..:D

Don't worry about bringing pizza..I make my own! See you tomorrow! :bigsmile:
 

·
Registered
Joined
·
1,208 Posts
After now close to 10 hours of tweaking (from getting it last Wed.) and playing with the pro eq and reverb 3d features I started to really explore the difference MCACC was providing when measuring my bi-polar high freq drivers. I noticed a little something on the 3d graph and started thinking maybe mcacc was really having a hayday with those highs. I will qualify: After constant calibrations and re-measuring using the 30-50ms vs. 20-40ms schemes my listening experiences were obvious but nothing drastic per se', but now when I removed the rear firing matched tweets the whole deal changed and high freqs were very different and measured better after viewing the eq sliders. The 20-40ms calibration was very encompassing and really thick and dimensional but I seemed to lack width. Again, the only thing I tried here was same 20-40ms calibration just minus the rear firing tweet. So, I re-did it this time with the suggested 30-50ms calibration and stage width was as big as my room, still had crazy depth, and just bigger. So, according to my surround reverb graphs I get that efficiency peak around 90ms and measure almost 5ft from listening position with mains almost 13ft. So my fellow room correction smart ones, can my rear firing tweet that I no longer use have made that much of a difference with all else the same? :nerd:


Brian in Bakersfield...
Have you tried rewiring your surrounds in a DIPOLE configuration ?
 

·
Registered
Joined
·
348 Posts
Discussion Starter #18 (Edited)
No, because of the way they are placed in the room. But, I have taken my "Front Alignment" calibration moved it to another saved program and copied the "All Channel Adjust" which is a "Flat" setting and applied to my side surrounds. So, I have the unique audio signature of my mains with a flat response for the side surrounds. With careful adjustment of the Trim controls, I think just 1db, I now have a super heightened sound field and the resolution is crazy solid. I'm still using the 40-60ms setting and all other measurements were left alone i.e, distance, levels, full freq phase control.
 

·
Premium Member
Joined
·
8,367 Posts
I've been doing some more tweaking of late and it just showed me that using the different modes can change how the system performs..
I've been using "All CH. Adjust" for all of my tweaking, just about since I first bought the unit..I did initially try all three modes but preferred the all ch.adjust setting..as a lot of people do..

The other night I decided to run "Symmetry" again to see what difference there is between the two..
I started from scratch using Full Auto to start, then "Keep SP Settings followed by "Auto"..I set EQ Pro. to 40-60 ms. and then checked my EQ bands..
The first thing I noticed was that 125hz. had been lowered several dB. over the All CH. Adjust setting.. Other frequencies looked to be about the same except for the surrounds which MCACC always lowers the 4Khz. band to ridiculous levels, so I put them up a bit..

I decided to try it how MCACC had set the EQ..without making any further adjustments..
The overall frequency range was very smooth with good voice definition in the centre channel..but two things stood out immediately..The mid to upper bass definition was much improved and with even better lower extension than All CH.Adjust..and the front to side surround projections were very precise..particularly with crowd scenes, which were more enveloping than previous..

Looks like I'll be staying with Symmetry for awhile! :T
 

·
Registered
Joined
·
348 Posts
Discussion Starter #20
I also like the Symmetry and the "thinking" behind it. In comparing eq levels for me the symmetry was like a "boosted" all channel adjust. It does provide a very dynamic sound and I too also enjoy the more aggressive surround effects it provides. I have all 4 programs using the 40-60ms setup. I still really enjoy re-doing everything using the Expert setup, just seems to be pretty smart in itself, but do notice a lack of high freq resolution in comparison to the Pro. I am constantly re-running while trying something different, fun, fun, fun!
 
1 - 20 of 66 Posts
Top