Mic and Speaker placement when not measuring the speakers

hey. everybody is talking about how to measure the Control room... but how to measure the live room? my question is where do i put the speaker and mic .. i have a genelec 1029 ... and where the behringer ecm 8000 mic? i thought i would always do the mic 2 meters from the speaker.. and do 8 measurments on diferent spots in the room with that setup.. and then see what happens.. and if i make the helmholtz resonator boxes from floor to the ceeling.. but only 65 cm wide.. will that be ok? i will but 5 of these in the room.. and i will fill out 2 corners.. other question i cant find is.. you can calculate the space for slat with the spreadsheet.. but what should be the pattern.. always same from floor to top.. or change the spcings and stuff.. if i have for instance more intensity on 200 hz.. do more of those and less peak on 150 do less of those on one resonator? please clarify.. should i use just helholtz in the corner and on walls.. or should i combine.. only cloth over wool in corners.. 2 panel absorbers and 3 helmholtz? I have whole ceeling covered with wool and thes thin plastic layer over it.. just like mr sayers sugessts...

Spock, try placing your speaker in a corner (as close to the tri-corner as possible) and your mic in the opposite corner (example - speaker in north-west corner at floor level, mic at south-east corner at ceiling level) - test there and with the mic at other ceiling corners as a comparison - a speaker placed in a tri-corner should excite ALL modes in the room, and a mic in the corner will pick all modes up equally, since ALL modes terminate at corners. So this method should show you all your room's response with as little effect from SBIR and "MBIR" as possible (that's Speaker Boundary Interference REsponse, and same effect with Microphone :wink: Good luck... Steve

Don't use a dipole speaker and use a omni mic. bert

Welcome back, Petar! You'll have to update your project thread one of these days... 8)

hey... i measured the room.. and documented it all with pictures and stuff.. if i do this right i will do a tutorial thread! :)... here some info.. and ETF files... maybe you steve can check it out in your ETF program.. and tell me if my intepretation is right.. LIVE ROOM - i already treated the ceeling with wool and put thin plastic (no fabric yet.. no money :) ) and i did the tricorner thing.. here is the speaker view of the mic... (you can see it in the other oposite tricorner..) - see what the highlights mean at the botom of the page and here is the response.. i think i have the porblem at about 80 Hz or? i did a few measurments ant this belov 56Hz thing only shows up in this measurment.. so maybe it is a flaw? it didn't show up in other corners though.. all other corners show the about 80 HZ peak.. how should i treat the room now? just for 80 hz? in 2 corners with bass traps? i will have altogeather 5 wall sections of resonators (resonators about 65x200 CM ) and 2 corners treated.. and i didn't exactley know how to interpret everything else.. how much reverb does my LR have now? i also did my empty control room.. a lot of reverb there.. and my dead room also.. (both totaly untreated) here so u see the difference here the ETF FIles http://www.octoberlight.net/hws_CR_MSLfull_1_1.zip http://www.octoberlight.net/hws_DR_MSLfull_1_1.zip it is 2:18 AM and i am dead..so i am going to bed.. hope somebody reads this :) one more question.. how big should my basstraps be in the rear of the CR... ? the bigger the better? here pics and the red shows where i planed to build the woll wall and then you know how the inner part goes :) LEFT part of the room and RIGHT part this looks cool with the highlighting in color.. so i thought i would explain what i am planing to do with the LIve room red marks where i thought of doing John's wall unit resonators and green marks where i thought of doing the bass trap unit john explained in the wall units section.. APRECIATE SOME INPUT! :) i hope to have this done by next weekend :) Petar

since everbody is ignoring me :) thought i'd continue with my work.. we treated the control room ceeling and dead room.. here the pics the treated ceeling the CR front wall dead room without cloth dead room with first layer particle stoper my brother after hard work my fiance and me testing the luminosity in the dead room (my pants button exploded cause i am too fat :) ) and here ther measurments for the rooms it shows like the same freequency problems as in the live room dead room should i treat the corners aditionaly in the dead room because of the peak in the low band... or leave it like that.. it is preety much dead :) and here the full spectrum for the live roomm is that normal? for enthusiasts and steve :) the zip file with all three measurments :) http://www.octoberlight.net/measurments_060204.zip would aprecciate a quick response.. on sound treatment input.. i have my first project next week :) PEtar

Petar, I'm sorry you haven't gotten any replies because your posts definitely deserve some attention. Here's my two cents: You need to set the Gate Time longer in ETF for those low frequency waterfall plots in order to get the highest resolution. You do not need to measure again! Just load the files you already have and set the Gate Time to the 200 millisecond maximum, then set the Time to as long as needed to see the complete decay. Also, the real value from such tests is to verify the improvement you got from treatment, and to ensure that the reverb time is relatively uniform at most frequencies. Regardless of what is measured initially, the treatment goal is generally the same: Broadband absorption that works well to as low a frequency as possible. --Ethan

Hey, i will ..thanks for the advice... what i need.. is a concrete suggestion what to do... :) broadband means helmholtz.. or your panel absorbers.. where, how big, what spacing, etc. etc :) of course i will measure again after the treatment to see the difference.. it seemes like my project has delayed for a week... so i have time to finish the treatment ..as i should! if you could jump in with concrete sugestions on what to do.. would be great.. i will build my soffit wall then next week also i think :) now that i have time 7 days.. :) i hope you will help me out here.. now in my last step to get it right :) Petar

Aloha and welcome to the forum Petar! :D Congrats on your studio build!

Any chance you could please: Edit your profile to include your location. This is very important, because this is a worldwide resource, and as such, material costs and availability vary widely. For example, masonry is cheaper than gypsum in some parts of the globe, whereas it's the exact opposite in other regions.

This will really come in handy two or three posts down the road. It's also part of the forum guidelines: http://www.johnlsayers.com/phpBB2/viewtopic.php?t=3231 Thanks! :wink: Looking forward to your build! Aloha 8)

hey.. im a while longer in this forum.. for almost year and a half now :)

Aloha Petar, Oops! sorry about that! :lol: Hey, that's great that you've been here that long. Your studio is looking great, but...you still might want to edit your profile. :wink: Aloha 8)

Ethan, thanks for the helping hand; been running on 4 hrs sleep for so long now it seems normal... :cry: I've not even had time to look at the zip files yet, hope to tonite at work if things are half-assed reasonable for a change. Petar, broadband is NOT a helmholtz or tuned panel, it's just more absorption like you've been doing. The next thing I'd do is heavy diagonal fill in room corners; I've seen quite a bit worse dips in rooms, so you're already gaining on it. It takes a LOT of volume to see marked changes in a room, I'd try to make the faces of your corner absorption at least a meter wide, more if you can, and at least 100mm thick (200 is better). Saw one comment about the "dead room with first layer particle stoper" - that's all you want, otherwise too much HF reflection most likely... Steve

LETS DO THE CONTROL ROOM FIRST! :) here is my proposal! but first... check out my KNIGHTFLY TM DIY MONITOR STANDS! :) with some patents of my own check it out.. good thing my fathers cousain has a wood shop i did it for the borrowed Dynaudios.. but they will work for my KRK v8 when i buy them someday :) here is my patent.. i put in this special screws wher i can drive in my spikes.. that are not made yet.. my neighbour is making them on his machine :) OK NOW TO THE CONTROL ROOM here the plan of the control room that i measured the other day 1. BACK WALL from my seat to the back it is about 3 m to the wool and 3,30 to the hard wall.. but knightfly says at least 3,80m so there is no sense in making a difusor in the back... correct me if i am wrong! :) although i would like to make one if neccesary so i can spend some time in the wood shop again :) RED COLOR IS for bass traps.. they are 170 cm wide and at least 80 cm deep PURPLE is wher this part of the wall sticks out in the back (the left side only) but to make it symetrical.. i draw it like that.. ..my idea was to put just wool on the right side and then cover it all with cloth from left to right :) GREEN is where i would put the wool from top to bottom in stead of the difusor :) here the detail for the green part. steve mentioned that it is good to move the wool away from the wall.. so that is what i plan to do :), it is so far away from the wall so it ends up in line with the wall part sticking out... but maybe i will do the green part 20 cm from the back.. and then do this 2 purpel parts 34 cm from the back wall so it stays symetrical 2. FRONT WALL since i will have free standing monitoring.. i will put wool all over the front wall.. again with the wool apart from the wall now if i should put slats and wood in the back or in the front.. please advise... but this is now not the issue i think.. and that i can start building the frames for that what i planned :) OFCOURSE.. INPUT IS AGAIN WELCOME! :) p.s steve.. the particle stoper i used in the dead room.. is what they use for the garden.. to cover it up in the winter i think.. it is 100% air transparent.. you don't feel any resistence while blowing trough it .. but watter can not go trough.. so i think it is not affecting the HF area :) or?

TODAY WAS A LONG DAY! here the results :) we started with the back wall.. and we made the front part (wool & wood) only temporary.. so we can remove if it is wrong :) here it goes.. THE BACK WALL Here is how i thought to do the back wall... with space behind the wool 100 mm and the bass traps.. here again when we put all the wool.. it was so DEAD that we decided not to do the front wall for now :) until i get some advice from you guys :) we put thin plastic on the ceeling.. and it became not so dead again :) and we where so eager that we put in the table and stands and the back couch :) check out the results :) see the right wooden part.. that is hollow.. we put some wool rests in it.. but it was meant so that the room would look symetrical.. (and be symetrical :) ) this is the table i will use.. for now.. it was for free.. so hey :) and it goes perfectly with the knightfly TM stands :) tomorrow i will do some measurements :) and then we will see how we managed the job what should i do with the front wall now... i thought if i put it in wool also.. the CR would be to dead.. or? Petar

It's 5 am here so gotta get some sleep, I'd hook up your speakers and play some commercial CD's, see how it sounds. Theory and tests are OK, but if it sounds good it IS good... (and if not, more rockwool across under window and wide across front corners... Steve

hey.. i did what you said.. and now i know what IMAGING means :) you can hear clearly in every song what is going on.. where everything is from speaker to speaker :) did you ever listen to SKATER BOI from avril lavigne.. on the first VERSE it has a super ultra low SYNTH (40 or 30 HZ) on every first beat the musical sentence (every 4 bars) check it out! you can feel it clearly in my room.. because the bass isn't muddy. :) one other thing.. i never was in a super good studio so i cannot compare it to anything.. but it is the best i have heard so far :).. if i hear a small reflection from the front.. that is not ok?. or :) but again i don't want the room to be to dead :) .. i will measure next week then i will know.. and we put bass traps in the live room.. sounds much better :) Petar p.s. anybody who reads.. check out the AVRIL LAVIGNE SKATER BOY.. and comment if you hear the ultra low synth on the first verse :)