Hello everybody!
As mentioned aready in the "Introductions" subforum - I'ts my 9th year here, but without writing anything... and the time has finally come 😉
I was always more into car audio. Where from one point of view active systems are even more common, but from the other I never got so deep into it as I need now.
I'm a Scan-Speak fan. Used Revelators in a few of my cars (still using in current one). Have a DIY Revelator 15W (+HDS tweeter) monitors as "PC speakers" wich I built myself based on this project from user @gornir
https://www.audioexcite.com/?page_id=59
Lately I came across nice floorstanders built on D2905/990000 + 15M/8631G00 (10l ported) and Seas CA25RE4X/DC (~60l ported) as a woofer, all ran from Hypex FA253 amps.
As they were in a bit of "unfinished project" state - no veneer (just painted plywood) and also no really properly designed/tuned x-over - the price was an absolute steal.... I just needed to have them.... 😉
I did some listening sessions. Did some (room?) measurements with REW and UMIK. Did some tuning. I'm even starting to be a bit happy with them but I know that all of it it's just wandering in the dark
I know how to use active crossover systems, I know a bit about measurements (not much but at least how to run/start them)
Once I had the Behringer 8000 mic and some phantom power XLR usb interface from M-Audio but I did sell it a long time ago.... Currently I have the UMIK1 USB microphone and access to some software but will it be enough?
In addition... I moved to a new house some time ago and my room is still untreated I'm working on it now) but even after the treatment....
I'd like to get into it as properly as possible... My main questions are.... Where should I begin (to read/learn)? Which way to go? Can I try to design a 3way crossover in a livingroom? Is my equipment enough? (If not) What should I buy? Or maybe I should try to design it in Virtuix CAD? I'm so so confused...
Thanks for any help
As mentioned aready in the "Introductions" subforum - I'ts my 9th year here, but without writing anything... and the time has finally come 😉
I was always more into car audio. Where from one point of view active systems are even more common, but from the other I never got so deep into it as I need now.
I'm a Scan-Speak fan. Used Revelators in a few of my cars (still using in current one). Have a DIY Revelator 15W (+HDS tweeter) monitors as "PC speakers" wich I built myself based on this project from user @gornir
https://www.audioexcite.com/?page_id=59
Lately I came across nice floorstanders built on D2905/990000 + 15M/8631G00 (10l ported) and Seas CA25RE4X/DC (~60l ported) as a woofer, all ran from Hypex FA253 amps.
As they were in a bit of "unfinished project" state - no veneer (just painted plywood) and also no really properly designed/tuned x-over - the price was an absolute steal.... I just needed to have them.... 😉
I did some listening sessions. Did some (room?) measurements with REW and UMIK. Did some tuning. I'm even starting to be a bit happy with them but I know that all of it it's just wandering in the dark
I know how to use active crossover systems, I know a bit about measurements (not much but at least how to run/start them)
Once I had the Behringer 8000 mic and some phantom power XLR usb interface from M-Audio but I did sell it a long time ago.... Currently I have the UMIK1 USB microphone and access to some software but will it be enough?
In addition... I moved to a new house some time ago and my room is still untreated I'm working on it now) but even after the treatment....
I'd like to get into it as properly as possible... My main questions are.... Where should I begin (to read/learn)? Which way to go? Can I try to design a 3way crossover in a livingroom? Is my equipment enough? (If not) What should I buy? Or maybe I should try to design it in Virtuix CAD? I'm so so confused...
Thanks for any help
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I don't understand the vertical labels on the three bottom charts. 250 m 500 m etc. Meters? I would expect charts to be labeled in decibels. The top charts does have decibels, and shows three room mode peaks, IMHO. Divide speed of sound by room dimensions to get frequencies. Peaks at 30, 60 120 hz. Must be a really big room. I have a 10 db peak at 200 hz in my room, the long dimension.
I break up standing waves in my room with furniture. Urethane stuffed couches and chairs, book record and CD shelves along the walls filled with product, pianos organs & organ speakers. Carpet on the floor and acoustic tile ceiling. At least buy a big rug.
You are gating your measurement with the software, don't you? Makes indoor measurement possible. See REW etc software tips on software thread. You'll get a better measurement with the speaker under test on a stand from the floor, like a stool. Freestanding from wall. You did have the omni mike on a stand didn't you?
Humps at 500 and 5000 hz, you can do something with crossover. First cut, 3 amp channels on one speaker, one for each driver, and some kind of active filter into the amps. I use graphic equalizer appliances because I don't like the feature of digital DSPs that the software goes obsolete when the cell phones update. You'd need 2 stereo equalizers or a 4 channel DSP. and some RCA cables. Warning, the 500 hump may be box dimension resonance, which might be damped down with internal wall treatment or stuffing. I liked the idea of Mr Clean magic pads on the speaker walls, available generic from ebay or someplace. Non flammable, no phosgene gas if your room catches fire.
I break up standing waves in my room with furniture. Urethane stuffed couches and chairs, book record and CD shelves along the walls filled with product, pianos organs & organ speakers. Carpet on the floor and acoustic tile ceiling. At least buy a big rug.
You are gating your measurement with the software, don't you? Makes indoor measurement possible. See REW etc software tips on software thread. You'll get a better measurement with the speaker under test on a stand from the floor, like a stool. Freestanding from wall. You did have the omni mike on a stand didn't you?
Humps at 500 and 5000 hz, you can do something with crossover. First cut, 3 amp channels on one speaker, one for each driver, and some kind of active filter into the amps. I use graphic equalizer appliances because I don't like the feature of digital DSPs that the software goes obsolete when the cell phones update. You'd need 2 stereo equalizers or a 4 channel DSP. and some RCA cables. Warning, the 500 hump may be box dimension resonance, which might be damped down with internal wall treatment or stuffing. I liked the idea of Mr Clean magic pads on the speaker walls, available generic from ebay or someplace. Non flammable, no phosgene gas if your room catches fire.
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They're miliseconds. Room is 489cm x 537cm x 253cm.
https://amcoustics.com/tools/amroc?l=489&w=537&h=253&r60=0.6
I have pretty lot of furniture and I'm currently building 12 sound absorbing panels to help... Anyway room acoustics is not the main topic of this thread... Most probably I will post another one in the proper sub-forum in a few days to talk about it and maybe post some measurements.
I have a delay with room treatment as I changed my mind about the panel fill material. Swapped rockwool for sheep wool due to health concerns and I'm waiting for supplies
https://amcoustics.com/tools/amroc?l=489&w=537&h=253&r60=0.6
I have pretty lot of furniture and I'm currently building 12 sound absorbing panels to help... Anyway room acoustics is not the main topic of this thread... Most probably I will post another one in the proper sub-forum in a few days to talk about it and maybe post some measurements.
I have a delay with room treatment as I changed my mind about the panel fill material. Swapped rockwool for sheep wool due to health concerns and I'm waiting for supplies
I only make Diy sealed sub thats very simple, also fan of scanspeak have 4X12'' discovery and 1X13'' revelator subwoofer drivers with 2000w@4ohm hypex plate amps.
I think measure only the tweeter 1m away with the mic aimed at the acoustic centre between the midrange/tweeter
do that also for the midrange and look where the best place is for the crossover.
set filter for tweeter and midrange en measure now with tweeter and midrange on and look for flat response.
do that also for the base driver ik think the mic can be in the same position on the acoustic centre.
I dont know if this is correct its my first tought about it
Use the normal calibration file for the umik1 not the 90 one thats for surround measurments as far i know.
I think measure only the tweeter 1m away with the mic aimed at the acoustic centre between the midrange/tweeter
do that also for the midrange and look where the best place is for the crossover.
set filter for tweeter and midrange en measure now with tweeter and midrange on and look for flat response.
do that also for the base driver ik think the mic can be in the same position on the acoustic centre.
I dont know if this is correct its my first tought about it
Use the normal calibration file for the umik1 not the 90 one thats for surround measurments as far i know.
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Quasi-anechoic measurement techniques are where you should focus your time initially. Without being able to do that properly, you'll get wagged around by measurement error and room response instead of what the speaker is actually doing on its own.
In-room response can also be used, but typically later in the process for final voicing, position optimization, etc. If your starting point is long-windowed in-room response and you adjust your DSP wholly or heavily on that, you are optimizing your design for one listening position and one speaker location, which is much more likely to sound wrong in other listening positions or if you change rooms or speaker locations. It's a straitjacket.
Nearly flat anechoic response should be the starting point for most designs, so understanding how to measure a close approximation of that in a non-professional environment is very useful. It's not difficult, but it does involve a number of details that often aren't obvious to those just starting out.
In-room response can also be used, but typically later in the process for final voicing, position optimization, etc. If your starting point is long-windowed in-room response and you adjust your DSP wholly or heavily on that, you are optimizing your design for one listening position and one speaker location, which is much more likely to sound wrong in other listening positions or if you change rooms or speaker locations. It's a straitjacket.
Nearly flat anechoic response should be the starting point for most designs, so understanding how to measure a close approximation of that in a non-professional environment is very useful. It's not difficult, but it does involve a number of details that often aren't obvious to those just starting out.
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Read this https://kimmosaunisto.net/Software/VituixCAD/VituixCAD_Measurement_REW.pdf
Once you have your measurements you can design your speaker in Vituixcad and then input all the filter values in Hypex Filter design
Yesssssss... @mattstat, "quasi anechoic" was the term I needed. Thanks... Did some studying till 2AM yesterday.... Soon will start to have some fun with the toys... or (most probably) discover that I'm in a deeper sh*t than I thought before 😉
Also I didn't know that I can simulate active crossovers in VirtuixCAD @shadowplay62 thank you
Also I didn't know that I can simulate active crossovers in VirtuixCAD @shadowplay62 thank you
This is written for MiniDSP & UMIK, but should apply to Hypex:
https://www.minidsp.com/applications/rew/measuring-time-delay