@strappo are you hollis over at ASR? That would make sense to me. I haven't visited there in ages since I got kicked out by their boss man for quite a silly reason really.
Would love to read more about your multi channel setup. I kind of regret not being in a position to do something similar myself. It should have the potential to be awesome but one heck of a puzzle to get right! 😀
Would love to read more about your multi channel setup. I kind of regret not being in a position to do something similar myself. It should have the potential to be awesome but one heck of a puzzle to get right! 😀
Yep! That’s me 🙂
I’ve been transitioning to real name but some servers have Hollis already taken. Now that l think of it l did reach out to you on ASR, makes perfect sense why l didnt hear back.
My plan over here is to post the final product, photos + measurements, then dive into the build history as time permits.
I’ve been putting the finishing touches on the center ch + placement. Its horizontal so, I’m gonna get some flak. Right now I’m not experiencing the expected “horrible combfiltering” as l move left to right on the couch, but man o man is it beaming in the upper highs and l gotta nail that angle to couch just right. You can only do so much with 3.25” driver spacing.
I’ve been transitioning to real name but some servers have Hollis already taken. Now that l think of it l did reach out to you on ASR, makes perfect sense why l didnt hear back.
My plan over here is to post the final product, photos + measurements, then dive into the build history as time permits.
I’ve been putting the finishing touches on the center ch + placement. Its horizontal so, I’m gonna get some flak. Right now I’m not experiencing the expected “horrible combfiltering” as l move left to right on the couch, but man o man is it beaming in the upper highs and l gotta nail that angle to couch just right. You can only do so much with 3.25” driver spacing.
I see your profile is still there at ASR? I read you last entries there and it seems you stepped out? (or was you account banned for some time?)
It seems really hard these days to stay in any group when you have one once of reasoning.
I've just been kicked out of yet another FB group, this time called Open Baffle only..., for telling a guy I wouldn't like his speakers much myself based on the FR he shared, and he went on a rant saying the proverbial "measurements don't tell everything" and that his speakers sounded marvelous and I was completely wrong to think otherwise. He then complained to the admins, who told me I was disrespectful and the admin booted me out!
I wish I could get the picture of the FR, but it seems the admin put my name on a black list and won't let me view the group at all.
Basically, it was a big spike at 30Hz, they a 12dBs chasm from 40Hz to 300Hz, a sudden rise of +12dBs and a jagged response all the way up.
Life will go on, but it seems the ones who know very little and are easily offended are winning the world over.
I miss the days when a member like Sreten could call someone's manure, and he would not get kicked out for not liking it!
Full story is here: https://www.diyaudio.com/community/...range-line-array.242171/page-395#post-7378292
He did ban me after that message even though my profile never showed it and it still looks like I'm just an (in)active member. I guess he expected me to ask to be re-instated or something? I dunno. Never had the intention to return. Overall a too fanatical bunch for me and not open minded enough to be able to see our world isn't black and white.
That I can agree with. Overall this place has been quite refreshing though. That's why I'm still here. 🙂
Donkey's like me don't know enough to annoy anyone else!
Meanwhile, everything here is pleasant enough, but i know there is more to have with some more precision/execution in EQ.
I will use the two stage EQ on Flex, using the input side to get some fundamental speaker EQ to bring the response to a reasonable level across the FR and the output side to correct phase and individual FR for each channel in the room, now all i need to do is work out how to execute that!
M
Meanwhile, everything here is pleasant enough, but i know there is more to have with some more precision/execution in EQ.
I will use the two stage EQ on Flex, using the input side to get some fundamental speaker EQ to bring the response to a reasonable level across the FR and the output side to correct phase and individual FR for each channel in the room, now all i need to do is work out how to execute that!
M
GOOD! You can never have too much EQ power 😀
Next to this I use 2 banks of parametric EQ in JRiver, 6 channels of FIR correction and believe it or not an overall EQ as plugin. This is just the fun stuff to create some (anti) cross talk management and ambience. Seen here is EQ for mains split in mid and side channels, one anti cross talk adjustment that goes to the rear channels, mid and side action for ambience channels and a bit of bass shifting in mid-side as well 😀. Now tell me I'm not crazy....
Next to this I use 2 banks of parametric EQ in JRiver, 6 channels of FIR correction and believe it or not an overall EQ as plugin. This is just the fun stuff to create some (anti) cross talk management and ambience. Seen here is EQ for mains split in mid and side channels, one anti cross talk adjustment that goes to the rear channels, mid and side action for ambience channels and a bit of bass shifting in mid-side as well 😀. Now tell me I'm not crazy....
So, what if anything have you done about phase please, i have read some stuff and it seems to all relate to crossovers or multi-driver-type set-ups not FR or multi-FR arrays..........
M
M
I wish I could give a simple answer, I even started an attempt at that. For me, the answer was using DRC-FIR to create a correction, for both phase and frequency response.
DRC-FIR is a very versatile tool and has a lot of variables you can use to determine the outcome. Long ago I studied all those fancy options to try and find the best ways to use it for my benefit. But my correction platform is/was way different from yours. I'm using a computer to load my FIR correction files and in doing so I can pick whatever length correction file I want. Number of taps so to speak. With your EQ tool you are most probably limited by what that tool has to offer. I use correction files that are 65536 taps long. That's a lot of EQ power which can do the work down to the lowest of frequencies. I doubt you will be anywhere near that number of taps available. Less taps means less (EQ) resolution at the lower frequencies. But you can still get some work done.
If you want phase corrections, you've got to be aware that reflections mess up the phase that we measure. Which is why we need to window our measurements which means we use a shorter time frame, which hopefully means getting the EQ done before the strong early reflections mess things up). But, a high frequency signal takes way less time than a lower frequency signal. This is why DRC-FIR uses a sliding window. Short where it can be short, at high frequencies and longer windows to cover the bass signals. That does mean that the lower we get down our frequency curve, trying to correct it, the more reflections will be part of our correction at those frequencies. No way around that I'm afraid, unless we can rid ourselves of those reflections. Sadly, in a real room that isn't going to happen. So the best thing we can do is try to find a correction that works across our listening area.
Cleaning up the room with treatment can bring the level of reflections down considerably. But as you may have guessed, it works quite well for higher frequencies, but not that well for the lower ones. Let's see an example of how that can look.
First up, my arrays in my room before I added any treatment:
Now a huge jump forward in time, with my shaded arrays and 3 pretty big panels in key places:
That's a big difference, right? It's also years of practice, learning, tweaks and some added experience over the years that make up this difference. And it may not even be needed. Let me explain:
A few posts ago I showed all kinds of EQ tweaks that I do for battling the cross talk we experience in a stereo setup. Want to know the truth about that? If I would have left out all treatment (and if I had a slightly better room than I currently own) the room would help fill in the blanks we get from that cross talk. We'd be alright. Different from what I have but alright. So I've done a lot of work but to what means?
I stole all early reflections and added generated new ones in it's place. Hiding the real properties of my room and putting a more idealized version in it's place. Good fun but lots of work.
If I were in your shoes I'd think about it if that's the route Id want to take. I say use what you've got for FIR correction and either use a tool like DRC-FIR, DIRAC or something more manual like RePhase to use all the taps you do have available. Play with it, see how far it can get you. My templates would be useless for you, as those are setup for using way more taps than you have available. When I started with DRC-FIR, I first used a program called DRC-Designer: https://www.alanjordan.org/DRCDesigner/HelpFrameset.html
That may help you get started. You won't need to use the measurement too that's included, you can use REW for that. You'd only need to rename the measurement to what DRC-Designer uses as default. After that you can quickly try a number of things and see/hear what that does.
Another start could be the tutorial gmad wrote with the help of a few of our friends here: https://www.diyaudio.com/community/...rical-loudspeaker-correction-networks.275730/
There's a tutorial there that should help you, but if you have questions we'd be around to help you out. I haven't used his method but my own isn't that far off. I even remember putting up my template and a few batch files I use way back when to help out. It's a long post already to I'll hit Post reply before I change my mind yet again.
Edit: one more note. Before running a program like DRC-FIR, get your frequency curve in shape with a feq EQ tweaks. Basically, you've done that already. That means DRC-FIR can correct more potential problems before you reach it's limits on how far it can boost or cut a frequency. So the basic EQ you have is fine, you can use the FIR correction on top of that to do fine tuning. That's what Dirac does too, you can probably do a better job by doing it yourself.
DRC-FIR is a very versatile tool and has a lot of variables you can use to determine the outcome. Long ago I studied all those fancy options to try and find the best ways to use it for my benefit. But my correction platform is/was way different from yours. I'm using a computer to load my FIR correction files and in doing so I can pick whatever length correction file I want. Number of taps so to speak. With your EQ tool you are most probably limited by what that tool has to offer. I use correction files that are 65536 taps long. That's a lot of EQ power which can do the work down to the lowest of frequencies. I doubt you will be anywhere near that number of taps available. Less taps means less (EQ) resolution at the lower frequencies. But you can still get some work done.
If you want phase corrections, you've got to be aware that reflections mess up the phase that we measure. Which is why we need to window our measurements which means we use a shorter time frame, which hopefully means getting the EQ done before the strong early reflections mess things up). But, a high frequency signal takes way less time than a lower frequency signal. This is why DRC-FIR uses a sliding window. Short where it can be short, at high frequencies and longer windows to cover the bass signals. That does mean that the lower we get down our frequency curve, trying to correct it, the more reflections will be part of our correction at those frequencies. No way around that I'm afraid, unless we can rid ourselves of those reflections. Sadly, in a real room that isn't going to happen. So the best thing we can do is try to find a correction that works across our listening area.
Cleaning up the room with treatment can bring the level of reflections down considerably. But as you may have guessed, it works quite well for higher frequencies, but not that well for the lower ones. Let's see an example of how that can look.
First up, my arrays in my room before I added any treatment:
Now a huge jump forward in time, with my shaded arrays and 3 pretty big panels in key places:
That's a big difference, right? It's also years of practice, learning, tweaks and some added experience over the years that make up this difference. And it may not even be needed. Let me explain:
A few posts ago I showed all kinds of EQ tweaks that I do for battling the cross talk we experience in a stereo setup. Want to know the truth about that? If I would have left out all treatment (and if I had a slightly better room than I currently own) the room would help fill in the blanks we get from that cross talk. We'd be alright. Different from what I have but alright. So I've done a lot of work but to what means?
I stole all early reflections and added generated new ones in it's place. Hiding the real properties of my room and putting a more idealized version in it's place. Good fun but lots of work.
If I were in your shoes I'd think about it if that's the route Id want to take. I say use what you've got for FIR correction and either use a tool like DRC-FIR, DIRAC or something more manual like RePhase to use all the taps you do have available. Play with it, see how far it can get you. My templates would be useless for you, as those are setup for using way more taps than you have available. When I started with DRC-FIR, I first used a program called DRC-Designer: https://www.alanjordan.org/DRCDesigner/HelpFrameset.html
That may help you get started. You won't need to use the measurement too that's included, you can use REW for that. You'd only need to rename the measurement to what DRC-Designer uses as default. After that you can quickly try a number of things and see/hear what that does.
Another start could be the tutorial gmad wrote with the help of a few of our friends here: https://www.diyaudio.com/community/...rical-loudspeaker-correction-networks.275730/
There's a tutorial there that should help you, but if you have questions we'd be around to help you out. I haven't used his method but my own isn't that far off. I even remember putting up my template and a few batch files I use way back when to help out. It's a long post already to I'll hit Post reply before I change my mind yet again.
Edit: one more note. Before running a program like DRC-FIR, get your frequency curve in shape with a feq EQ tweaks. Basically, you've done that already. That means DRC-FIR can correct more potential problems before you reach it's limits on how far it can boost or cut a frequency. So the basic EQ you have is fine, you can use the FIR correction on top of that to do fine tuning. That's what Dirac does too, you can probably do a better job by doing it yourself.
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The "purists" would so throw a tantrum looking at all those graphics! ha ha!
I see it all the time... my design / my drivers don't need any EQ, they are so good...
That means they've never actually listened to a finely tuned system, don't want to spend time learning about this (it's not just like moving an EQ slider up or down and it's done!) and want to advertise themselves or their driver company that they are so good, they don't need anything to fix.
I've never come across a driver, cheap nor expensive, that didn't need some work to sound amazing. Some are very good and need only a little work to sound great, some need more work, but eventually get there.
Of course, a flawed driver (major breakup / lots of distortion) will never be great, no matter how much work one tries... it's just a lost cause. Luckily, driver manufacturers have more and more tools and experience to come up with reasonably good drivers these days.
Yes, I'm getting off most of FB groups. Almost all of them are run by people who don't even know anything about the subject (can they monetize a group? It certainly feels like it) and are super flaky, no room to disagree with another member. Not talking about calling names on other members, just disagreeing with a member will get you banned!!!
I'm happy that at DIYAudio, one can still disagree with people, respectfully, and not get banned! 🙂
I read the whole story now and still don't get why...
You where a bit searching the confrontation and there could have been a bit more respect from your side, but still no reason ban I would say...
And as always you are prepared to try to explain, many thanks, knowing your story way back, when doing the amplifier test visit, i know you "started somewhere" i will never go so deep but some shortcuts certainly help
Flex gives me 4096 to split between channels
I may have an opportunity with the front wall to do some treatment in between the speakers as i need to tidy it all up anyway, and i have some portable panels made for another room and system so i shall experiment at some point but we are coming up to Christmas time and visitors now
I can see the difference in the graphs and i feel they represent % of the original impulse after time, but need to learn some interpretation skillsI - what does that mean/or sound like
The folk around MiniDSP suggest RePhase, and i like the fact that manual means that you have to underststand the process a little more
That's where i shall start
Thanks again
If you go the RePhase route: https://www.diyaudio.com/community/...nearization-eq-and-fir-filtering-tool.221434/
Huge thread, you're going to need some time off from having visitors over for that 😀.
There's a trick I want to show you in REW that you could use as input for RePhase.
We need to center our IR peak at zero first, go to the IR tab in REW (only needed if it isn't centered automatically upon making the measurement):
Click "Estimate IR delay" and use shift IR. That wil shift the main peak to the zero spot.
I've talked about that sliding window in DRC-FIR. REW does have something similar, not quite the same but it may help you avoid over-correcting. In REW (and DRC) it is called a frequency dependent window. On a measurement one can apply such a frequency dependent window by clicking IR windows and following the settings on the next picture:
(please notice I've only selected one measurement, going to a single measurement on it's "SPL & Phase" tab works better, just not inclined to do it all over 😉.
Next click apply window:
You'll see a smoothed version of the previous measurement. This is the one I'd recommend to use in RePhase. But you can't export it like that, we've only applied a window to it, exporting the IR still results in the original measured IR.
So we need a little trick to get it. On the "All SPL" tab, click "Controls" and Choose "Alignment tool".
Don't change any of the settings, just click "Aligned copy". Now we have two exactly the same looking frequency curves. (you'll see a third one here at the bottom of the screen because I used screen grabs along the way to tell the story, ignore that one)
Make sure when in the "All SPL" tab, only the 2 same graphs are showing by deselecting the others at the bottom of the screen.
To give a little more insight, the copy we created is exactly the same as our original measurement. So we aren't finished yet.
Still using that "Controls" menu, we now select "Vector Average" while we have both (just those two we want) 'frequency shaded' graphs active.
A new frequency shaded IR will appear, one that we can export as a Wav and use in RePhase.
This one has that frequency shaded window applied and cannot be restored like our original measurement or the copy we made. But it's an early look at the frequency curve, excluding many reflections, except at the lower frequencies where we cannot avoid them. If you look at it on all tabs you'll see its a smoothed version with a shorter time frame. The reason to use this in RePhase is to leave out as much of the room anomalies as possible, similar to what the packages like DRC-FIR, Audiolense and Accourate do. Not quite the same, just similar.
Another long story... got to run now.
Huge thread, you're going to need some time off from having visitors over for that 😀.
There's a trick I want to show you in REW that you could use as input for RePhase.
We need to center our IR peak at zero first, go to the IR tab in REW (only needed if it isn't centered automatically upon making the measurement):
Click "Estimate IR delay" and use shift IR. That wil shift the main peak to the zero spot.
I've talked about that sliding window in DRC-FIR. REW does have something similar, not quite the same but it may help you avoid over-correcting. In REW (and DRC) it is called a frequency dependent window. On a measurement one can apply such a frequency dependent window by clicking IR windows and following the settings on the next picture:
(please notice I've only selected one measurement, going to a single measurement on it's "SPL & Phase" tab works better, just not inclined to do it all over 😉.
Next click apply window:
You'll see a smoothed version of the previous measurement. This is the one I'd recommend to use in RePhase. But you can't export it like that, we've only applied a window to it, exporting the IR still results in the original measured IR.
So we need a little trick to get it. On the "All SPL" tab, click "Controls" and Choose "Alignment tool".
Don't change any of the settings, just click "Aligned copy". Now we have two exactly the same looking frequency curves. (you'll see a third one here at the bottom of the screen because I used screen grabs along the way to tell the story, ignore that one)
Make sure when in the "All SPL" tab, only the 2 same graphs are showing by deselecting the others at the bottom of the screen.
To give a little more insight, the copy we created is exactly the same as our original measurement. So we aren't finished yet.
Still using that "Controls" menu, we now select "Vector Average" while we have both (just those two we want) 'frequency shaded' graphs active.
A new frequency shaded IR will appear, one that we can export as a Wav and use in RePhase.
This one has that frequency shaded window applied and cannot be restored like our original measurement or the copy we made. But it's an early look at the frequency curve, excluding many reflections, except at the lower frequencies where we cannot avoid them. If you look at it on all tabs you'll see its a smoothed version with a shorter time frame. The reason to use this in RePhase is to leave out as much of the room anomalies as possible, similar to what the packages like DRC-FIR, Audiolense and Accourate do. Not quite the same, just similar.
Another long story... got to run now.
Really useful inputs thanks, i have so much to understand and learn.
I have read through above and started to grasp a few parts, but lots to revisit, and as you say unlikely to happen over the holiday period.
How absorbent (at various frequencies) are Christmas trees, because theres one in the way now!
M
I have read through above and started to grasp a few parts, but lots to revisit, and as you say unlikely to happen over the holiday period.
How absorbent (at various frequencies) are Christmas trees, because theres one in the way now!
M