Trying to dust the cobwebs off.

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Grant Bunter
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Re: Trying to dust the cobwebs off.

#16 Post by Grant Bunter » Mon Feb 24, 2020 3:51 pm

While you created the thread, you aren't the only person who reads it!
EQ is mandatory is like a mantra to me. So is displacement limit Bill's cab designs as per the values in the plans.
Don't take anything I'm writing here personally.

Don't sweat it! Limiting is limiting. Like anything there's probably at least 2 ways or more to approach it.
For subs, with channel strip fader and master output at unity, I play a sine wave at 60Hz, and wind back the limiter until my DMM (set on 200V AC) reads the value I need as stated in the plans (with cabs connected). The test is then to slam your mixer faders to full on, and see if your limiter light engages, and your voltage doesn't change. If nothing changes, you're done.

You're right, it's highly unlikely your QSC's limiter are brick wall. They are probably peak limiters, and that's what we don't want to use.

Regarding plots and what you see. well, of course it's going to not be like the plots. Those plots are done in anechoic chambers and show baseline response, which will be about perfect outside, but put in a room, any room, and response changes, and no 2 rooms are the same.

Best to use a reference EQ as a saved target, and get RTA to EQ to the target. That way it tunes your system to the room...
Built:
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" BP102 , 2 x 28" 3012lf.
WH8: x 3 with melded array.
Bunter's Audio and Lighting "like"s would be most appreciated...

Bruce Weldy
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Re: Trying to dust the cobwebs off.

#17 Post by Bruce Weldy » Mon Feb 24, 2020 4:50 pm

Grant Bunter wrote:
Mon Feb 24, 2020 3:51 pm
it's highly unlikely your QSC's limiter are brick wall. They are probably peak limiters, and that's what we don't want to use.

Depends on the model. It looks like the PLD definitely has voltage limiting, the GXD manual isn't as forthcoming as the PLD....none of the other models have it.

You could always test it out and see if it holds.

But, the Protea should definitely be able to limit properly for you.....that's where I'd do it.

6 - T39 4-25" 2-22" 3012LF
4 - OT12 2512 Melded/NSD2005
1 - T24
2 - XF210


"A system with a few knobs set up by someone who knows what they are doing is always better than one with a lot of knobs set up by someone who doesn't."

himhimself
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Location: Bloomington IN

Re: Trying to dust the cobwebs off.

#18 Post by himhimself » Mon Feb 24, 2020 5:17 pm

For subs, with channel strip fader and master output at unity, I play a sine wave at 60Hz, and wind back the limiter until my DMM (set on 200V AC) reads the value I need as stated in the plans (with cabs connected).
Grant, I think you meant to say with cabs not connected.
Attach your meter to the amp output, no cabs.
2xT30 (20", 3012LF)
2xT30 (21", 3012LF)
4xOtop J-array (Beta12, melded/straight piezos)
Truck Tuba (MCM)
Next up: 2xJack12 or family of table tubas

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Seth
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Re: Trying to dust the cobwebs off.

#19 Post by Seth » Mon Feb 24, 2020 6:59 pm

5meohd wrote:
Fri Feb 21, 2020 10:17 am
Hello!!

It's been a long time since I've been here...
Hey, I'm Seth. What can I call you?

What drivers do you have in your T60's?

Also, I use the Protea Software and DSP in my Ashly amps. I think it's the same user interface you use, Protea NE Software Version 5.49 on PC. I've found that the limiter is only adjustable in whole (or was it half?) dB increments, which makes it nearly impossible to dial in an exact voltage. However, placing a virtual attenuater just after the limiter in the signal chain allows finer control to dial back just a bit once the limiter is set one dB above the desired resultant voltage output.

Not only will the room change the measured curve from what the advertised response curve, but simply putting it in an enclosure greatly changes response. I wouldn't worry about it too much. Like you seem to be, I also like to be a little more precise and scientific about things. Be able to see results, not just hear them. Be able to compare with my eyes as well as my ears. I get it. Here's what I would personally do if I were in your shoes and wanted to get a base tune to run for the time being, until further testing and tuning is possible.

Pretty much what Grant said already;
High pass the sub 48LR @ 25, Low pass 24LR @ 100
High pass mid 24LR @ 100, Low pass 24LR @ 2500
High pass Tweets 24LR @ 2500, I personally wouldn't bother putting an upper low pass on the tweets, but it wouldn't hurt anything to do it.

You can pretty easily rough the amp levels in. If something is jumping out, turn that amps signal down in Protea.

Other than that, it's either your ears or your microphone/computer. Seems most here are more apt to rely on their ears. I often hear/read "If it sounds good it is good." Logical.

For the record, your Jack 10's should do nicely with the T60's. Is there something specific that has you using this untested non-professionally designed conglomeration of parts instead? I totally get it if it's just because you want to. Don't have to explain yourself to (the likes of) me. Was just curious if there is some deficiency you've identified in the Jacks.

Anyway, welcome back. I look forward to getting this sorted and hearing of your results :thumbsup:




-Seth-
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

Grant Bunter
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Re: Trying to dust the cobwebs off.

#20 Post by Grant Bunter » Tue Feb 25, 2020 3:45 am

SethRocksYou wrote:
Mon Feb 24, 2020 6:59 pm

Pretty much what Grant said already;
High pass the sub 48LR @ 25, Low pass 24LR @ 100
High pass mid 24LR @ 100, Low pass 24LR @ 2500
High pass Tweets 24LR @ 2500, I personally wouldn't bother putting an upper low pass on the tweets, but it wouldn't hurt anything to do it.
I thought 2.5K was stretching the B&C, which is why I recommended 2K instead (The JayBee would probably handle 1.5K and up well enough, but I felt it was a nice compromise with the B&C to go with 2K for both).

The rising to 2.5K we see with Eminence isn't there in so many other brands...
Built:
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" BP102 , 2 x 28" 3012lf.
WH8: x 3 with melded array.
Bunter's Audio and Lighting "like"s would be most appreciated...

5meohd
Posts: 104
Joined: Thu Nov 18, 2010 4:47 pm

Re: Trying to dust the cobwebs off.

#21 Post by 5meohd » Tue Feb 25, 2020 11:02 am

OK. Thanks again for any/all suggestions and conversation.

I spent 9hrs on it yesterday with a friend to bounce logic off of.
We started from scratch and built the xover and eq settings Grant recommended. Listened to my reference track (https://blkrtz.bandcamp.com/track/aint- ... -feat-fink) and decided that it was nice and of course still needed work. All graphs are 1/6th smoothing.
Screen Shot 2020-02-24 at 12.41.37 PM.png
So we placed an RTA 1 meter from the center point between the JBL and B&C, muted the subs and started with sweeping and and examining each xover type. By looking at the REW plots it was clear that the Buttersworth 12dB filters made the most sense for crossing the B&C to the JBL in these cabinets.

We then proceeded to use the Ashly DSP to get a +/- 2.5dB response from about 100Hz to 10kHz for each speaker. These horns are really tapering off the JBL driver at that point. We ended up adding a high shelf to get a little more energy up there and it still only added a couple dB. Now, I realize this wasn't recommended necessarily and doesnt compare to doing this in a free field.. BUT. We unmuted the subs and WOW. We listened to the reference track at this point and it was the best I'd ever heard it. Then we listened to one of the tracks I'm most excited to play in my set this Saturday (https://deepmedimusik.bandcamp.com/track/avet) and it was Jaw On The Floor Mother Of God stuff.

We then pointed the RTA at the center of the moth of the sub just to see what it looked like.. interesting.. probably worthless data though.

Here is where things get way off track (admittedly, so please, if your going to comment give me as much depth and reasoning as possible!). The bass was still too "muddy". We also have a unique setup for these particular events. We have the DJ booth right in the sweet spot of the room. 38% of the length of the room centered between the mains in the picture. Its incredible. The time delay is a minor challenge for the beat-matching, but they say its workable. This whole idea launched as just "loft parties" but with our rig. So the feel was supposed be similar to just hanging out playing records at a friends like we used to... and integrating a monitor system into this awkward space is probably wise, but not "fun".

Anyway... We decided to put he RTA mic at ear height right where you stand at the DJ mixer to attempt to give the DJ a clear canvas to paint on. Ended up making about 4 eq adjustments to the subs and checking both tunes.. minor improvement at the mix position and no noticeable degradation anywhere else. Nothing over 4dB. Ended up with +/- 4.5dB from 25Hz to 100hz! Sounding THICK. But.. the "natural" response looks quite strange now.. measuring the full bandwidth at mix position lead to a few more notches in the mains and we ended up with this
Screen Shot 2020-02-24 at 5.25.33 PM.png
Now.. listening to the reference track and all of the sudden that vocal was really harsh again. I start panicking because I'm running out of time. I delete the notches made because mix position sweep data and I hear a minor improvement. I realize I've switched traktor from running out via a Motu interface to using the Pioneer DJM750mk2 as its interface and traktor's internal "headroom" setting was at -3 instead of -9. Change that to -9 and re-match gain structure via pioneer and I hear another minor improvement. Still.. Yuck. I bring the levels of the B&C and JBL down 3dB and I hear another improvement. But still harshness exists.

Time to leave. SH$t.

I'm probably heading back today but won't be able to play at full volume. :wall:

I think its a combination of: too high of expectations (chasing the Danley Labs dragon), fatigue from being 8hrs in, and maybe a little tweak or two left. In general the people who walked in right at the end to get a preview were completely amazed.

I've done some peak eq sweeping of the reference track in my DAW and found that from 13-14kHz is the area where my ear feels "pain". So that'll be the first move. I've also grabbed the BSS 30band EQ out of storage. should be quick to adjust a band up and down and listen to the subjective interaction. I'm also thinking about doing the classic "pink out the room" with the BSS and the turning eq on/off with a variety of tracks to see if it doing more harm than good.

Cheers.
4 T60's
4 piezo J10's

now working on a 7.1 system

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Seth
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Re: Trying to dust the cobwebs off.

#22 Post by Seth » Tue Feb 25, 2020 12:51 pm

Grant Bunter wrote:
Tue Feb 25, 2020 3:45 am
I thought 2.5K was stretching the B&C, which is why I recommended 2K instead...
You're right, that's probably a better place to start. :thumbsup:
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

Grant Bunter
Posts: 6626
Joined: Mon Nov 28, 2011 11:12 am
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Re: Trying to dust the cobwebs off.

#23 Post by Grant Bunter » Tue Feb 25, 2020 4:05 pm

5meohd wrote:
Tue Feb 25, 2020 11:02 am
Listened to my reference track (https://blkrtz.bandcamp.com/track/aint- ... -feat-fink) and decided that it was nice and of course still needed work. All graphs are 1/6th smoothing.

Screen Shot 2020-02-24 at 12.41.37 PM.png

So we placed an RTA 1 meter from the center point between the JBL and B&C, muted the subs and started with sweeping and and examining each xover type. By looking at the REW plots it was clear that the Buttersworth 12dB filters made the most sense for crossing the B&C to the JBL in these cabinets.

We then proceeded to use the Ashly DSP to get a +/- 2.5dB response from about 100Hz to 10kHz for each speaker. These horns are really tapering off the JBL driver at that point. We ended up adding a high shelf to get a little more energy up there and it still only added a couple dB. Now, I realize this wasn't recommended necessarily and doesnt compare to doing this in a free field.. BUT. We unmuted the subs and WOW. We listened to the reference track at this point and it was the best I'd ever heard it. Then we listened to one of the tracks I'm most excited to play in my set this Saturday (https://deepmedimusik.bandcamp.com/track/avet) and it was Jaw On The Floor Mother Of God stuff.

We then pointed the RTA at the center of the moth of the sub just to see what it looked like.. interesting.. probably worthless data though.

Here is where things get way off track (admittedly, so please, if your going to comment give me as much depth and reasoning as possible!). The bass was still too "muddy". We also have a unique setup for these particular events. We have the DJ booth right in the sweet spot of the room. 38% of the length of the room centered between the mains in the picture. Its incredible. The time delay is a minor challenge for the beat-matching, but they say its workable. This whole idea launched as just "loft parties" but with our rig. So the feel was supposed be similar to just hanging out playing records at a friends like we used to... and integrating a monitor system into this awkward space is probably wise, but not "fun".

Anyway... We decided to put he RTA mic at ear height right where you stand at the DJ mixer to attempt to give the DJ a clear canvas to paint on. Ended up making about 4 eq adjustments to the subs and checking both tunes.. minor improvement at the mix position and no noticeable degradation anywhere else. Nothing over 4dB. Ended up with +/- 4.5dB from 25Hz to 100hz! Sounding THICK. But.. the "natural" response looks quite strange now.. measuring the full bandwidth at mix position lead to a few more notches in the mains and we ended up with this Screen Shot 2020-02-24 at 5.25.33 PM.png

Now.. listening to the reference track and all of the sudden that vocal was really harsh again. I start panicking because I'm running out of time. I delete the notches made because mix position sweep data and I hear a minor improvement. I realize I've switched traktor from running out via a Motu interface to using the Pioneer DJM750mk2 as its interface and traktor's internal "headroom" setting was at -3 instead of -9. Change that to -9 and re-match gain structure via pioneer and I hear another minor improvement. Still.. Yuck. I bring the levels of the B&C and JBL down 3dB and I hear another improvement. But still harshness exists.

In general the people who walked in right at the end to get a preview were completely amazed.

I've done some peak eq sweeping of the reference track in my DAW and found that from 13-14kHz is the area where my ear feels "pain". So that'll be the first move. I've also grabbed the BSS 30band EQ out of storage. should be quick to adjust a band up and down and listen to the subjective interaction. I'm also thinking about doing the classic "pink out the room" with the BSS and the turning eq on/off with a variety of tracks to see if it doing more harm than good.

Cheers.
You're first screen shot is probably the room.
When you slip in the BSS, try a -3dB notch at 250Hz and 2.5K.
Check your REW settings to see if it's set to equal loudness curves (if yes, turn it off) or has weighting (eg A or C). If you can, turn all weighting off.

I'm a little surprised at subs response, but again think it's the room or some setting.
Measure subs from further away.

You may be getting some rumble from the subs. Have you ever run through all your tracks and actually worked out how much LF energy is there, and how low? If you can raise the T60's up from 25Hz because there is no content there, that's going to be a good thing.
Later, one day, run your songs through something like audacity, which let's you examine frequency content. Then you'll know.

In order to protect your Jaybee's more, try this, and if it sounds ok, use BW24 on their high pass rather than BW12.

Other than that, the first tweak after initial setup brought about the most significant improvement from a listening perspective.
That's where I'd stay until I actually worked out exactly what's going on...
Built:
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" BP102 , 2 x 28" 3012lf.
WH8: x 3 with melded array.
Bunter's Audio and Lighting "like"s would be most appreciated...

5meohd
Posts: 104
Joined: Thu Nov 18, 2010 4:47 pm

Re: Trying to dust the cobwebs off.

#24 Post by 5meohd » Wed Feb 26, 2020 10:03 am

Can you elaborate a little on the surprise of subs response?

the first chart is with subs muted. I think I failed to mention that. Sorry.
4 T60's
4 piezo J10's

now working on a 7.1 system

5meohd
Posts: 104
Joined: Thu Nov 18, 2010 4:47 pm

Re: Trying to dust the cobwebs off.

#25 Post by 5meohd » Wed Feb 26, 2020 12:02 pm

I'm curious about the HPF setting on the subs. I'm looking at tracks with Voxengo Span in my DAW. I do see sweeps dipping to 22-25ish.. but of course the fundamental notes of the tracks are mostly 30 and up.

Is the recommended HPF setting in the build doc? I want to make sure I'm getting as much energy potential as possible.
Concentrate.Instructions.JPG
Concenrate-Hedera.JPG
4 T60's
4 piezo J10's

now working on a 7.1 system

Grant Bunter
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Joined: Mon Nov 28, 2011 11:12 am
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Re: Trying to dust the cobwebs off.

#26 Post by Grant Bunter » Wed Feb 26, 2020 2:58 pm

5meohd wrote:
Wed Feb 26, 2020 10:03 am
Can you elaborate a little on the surprise of subs response?

the first chart is with subs muted. I think I failed to mention that. Sorry.
That makes more sense.
5meohd wrote:
Wed Feb 26, 2020 12:02 pm
I'm curious about the HPF setting on the subs. I'm looking at tracks with Voxengo Span in my DAW. I do see sweeps dipping to 22-25ish.. but of course the fundamental notes of the tracks are mostly 30 and up.

Is the recommended HPF setting in the build doc? I want to make sure I'm getting as much energy potential as possible.
Yes, it's in build doc. "High pass filter at 25 to 30Hz". Speaker cabs are not headphones. Don't lower the HP.
Built:
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" BP102 , 2 x 28" 3012lf.
WH8: x 3 with melded array.
Bunter's Audio and Lighting "like"s would be most appreciated...

5meohd
Posts: 104
Joined: Thu Nov 18, 2010 4:47 pm

Re: Trying to dust the cobwebs off.

#27 Post by 5meohd » Wed Feb 26, 2020 3:11 pm

Got it! I dug out the old doc and read through it. Been a while.
4 T60's
4 piezo J10's

now working on a 7.1 system

5meohd
Posts: 104
Joined: Thu Nov 18, 2010 4:47 pm

Re: Trying to dust the cobwebs off.

#28 Post by 5meohd » Fri Feb 28, 2020 11:58 am

Interesting side tangent in development:
lookingatfront.jpg
lookingatback.jpg
fromkitchen.jpg
Getting a head start here... What do you think would be optimal placement for 4 T60s in that space?

Looks to be about 50'x100' with 15' ceiling. +/- a few feet.
4 T60's
4 piezo J10's

now working on a 7.1 system

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Seth
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Re: Trying to dust the cobwebs off.

#29 Post by Seth » Sat Feb 29, 2020 2:58 am

First spot I'd try out... First pic, corner loaded in the corner to the left of, and on the same wall as the door.

How much room is in the corner to the left of the doors in pic 2?

Have you heard of the sub crawl?
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

5meohd
Posts: 104
Joined: Thu Nov 18, 2010 4:47 pm

Re: Trying to dust the cobwebs off.

#30 Post by 5meohd » Tue Mar 03, 2020 2:21 pm

That corner is indeed what I was thinking. Would you try to stack all 4 subs vertically facing the corner? Or put them in a cube orientation? I wish the sub placement sticky had T60 guidelines...
4 T60's
4 piezo J10's

now working on a 7.1 system

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