4 July Hi-Fi

#1
The best thing about the 4th of July, aside from celebrating American independence, is that you can make lots of noise in a suburban neighborhood and the cops don't come. This block party has been going on for 40+ years and I first provided sound, such as it was, in about 1976.

I got to try out the new toys, which are still somewhat under development as a system. No live band this year, just playback and announcing.

IMG_3383.jpg IMG_3365.jpg IMG_3367.jpg IMG_3368.jpg IMG_3370.jpg IMG_3374.jpg

Some observations:

The end-fire sub array used 4.5 ft and 4 ms so as to put the null at 63 Hz. I measured the frequency response at ground level at both 40 ft in front of and behind the array and achieved a difference of 16 dB at 63 Hz.

The SH-46s were flown at 13 ft separated by ~25 ft using 10 deg of down-tilt and toed-in 20 deg, so that the outer speaker pointed straight down the street. I came up with this using Danley's 3-D modeling tool but would be interested what more experienced folks would have done under these circumstances. The street is 30 ft wide and most of the people were between 30 and 200 ft out.

The Lectrosonics HM transmitter easily reached the 630 ft to the far end of the block. It was fun seeing how many words I could get out before hearing myself. The pro voice-over guy who led the kid's games and did most of the announcing didn't seem to have any trouble speaking over the delay.

The attached SM-58 was at grave risk from ejecta during the game of Chubby Bunny (pictured) where the object is to put as many marshmallows as possible in your mouth, without swallowing, while saying "chubby bunny" 3 times. It and the transmitter survived a 3 ft fall onto the concrete with no damage -- thank you Shure, Lectro, and the limiters.

During the fireworks, which are lit off every year by an honest-to-God rocket scientist, I played Tchaikovsky's 1812 Marche Slave (American cheese supplied by a Russian, at its best). The TH-118s seemed to like the cannon shots. A good time was had by all, except maybe a few dogs.

Happy Fourth,

--Frank
 
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Jan 11, 2011
188
0
0
Upstate SC
#2
Looks like more fun than I had. A little more trim height and that rig could cover quite the crowd.

So did you play the 1812 Overture or Marche Slave or both? They are two different pieces.

Sent from my neural implant
 
Jan 11, 2011
804
7
18
Florida
#5
Re: 4 July Hi-Fi

T
Some observations:

The end-fire sub array used 4.5 ft and 4 ms so as to put the null at 63 Hz. I measured the frequency response at ground level at both 40 ft in front of and behind the array and achieved a difference of 16 dB at 63 Hz.
Frank,

I think I would have used 9.75 degree down tilt ;^).

How does that 16 dB level difference compare with four TH-118 in a 2 high 2 wide mouth together "normal" configuration ?
Did you happen to save traces of the in front and behind measurements?

Art
 
#6
Re: 4 July Hi-Fi

Frank,
How does that 16 dB level difference compare with four TH-118 in a 2 high 2 wide mouth together "normal" configuration ?
Did you happen to save traces of the in front and behind measurements?
Art
Art,

I'm pretty new to all this and it was the first time I set up all 4 TH-118s together, so I don't have a basis for comparison. It would have been easy to slide back 2 of them and turn off the delay but I didn't think of it and was eager to get things set up.

I do, however, have the traces. This was a good exercise in getting them out of Smaart and into the Forum. I used: control print screen; "paint"; memory stick (to move computers); Photoshop (crop and resize). Maybe there's an easier way...

subRear40ft.jpg subFront40ft.jpg

--Frank
 
#7
Re: 4 July Hi-Fi

Art,

I'm pretty new to all this and it was the first time I set up all 4 TH-118s together, so I don't have a basis for comparison. It would have been easy to slide back 2 of them and turn off the delay but I didn't think of it and was eager to get things set up.

I do, however, have the traces. This was a good exercise in getting them out of Smaart and into the Forum. I used: control print screen; "paint"; memory stick (to move computers); Photoshop (crop and resize). Maybe there's an easier way...

View attachment 7419 View attachment 7420

--Frank
Irfanview

Or the integrated snipping tool
 
Jan 11, 2011
804
7
18
Florida
#8
Re: 4 July Hi-Fi

Art,

I'm pretty new to all this and it was the first time I set up all 4 TH-118s together, so I don't have a basis for comparison. It would have been easy to slide back 2 of them and turn off the delay but I didn't think of it and was eager to get things set up.
That is quite a "hole in the middle".

One thing I notice is the steep LF rolloff on your TH-118 looks a bit more like my Keystone TH using the BC-18SW115-4 than Langston Holland's 18sound loaded TH-118.
The Keystone is the blue trace, Langston's TH-115 is the purple, white is his TH-118.

Are yours loaded with BC-18SW115-4?
What filter settings were you using?
 

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#9
Re: 4 July Hi-Fi

That is quite a "hole in the middle".
One thing I notice is the steep LF rolloff on your TH-118 looks a bit more like my Keystone TH using the BC-18SW115-4 than Langston Holland's 18sound loaded TH-118.
The Keystone is the blue trace, Langston's TH-115 is the purple, white is his TH-118.
Are yours loaded with BC-18SW115-4?
What filter settings were you using?
That is a B&C 18SW115-4. The high-pass is 24 dB/oct Butterworth at 25 Hz. The low-pass is 24 dB/oct Linkwitz-Riley at 90 Hz.

I attribute the nice "hole" to a near ideal environment: No nearby reflecting surfaces in front or behind (other than the flat, hard ground) and a nice straight crack down the middle of the concrete street for me to use to position the measurement mic exactly on axis.

Silas: Thanks for pointing out the snipping tool. I was so busy hating W7 that I didn't imagine that it could have any useful new features :)~:)~:smile:

--Frank
 

Ivan Beaver

Graduate Student
Jan 11, 2011
2,300
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Atlanta GA area
#10
Re: 4 July Hi-Fi

That is quite a "hole in the middle".

One thing I notice is the steep LF rolloff on your TH-118 looks a bit more like my Keystone TH using the BC-18SW115-4 than Langston Holland's 18sound loaded TH-118.
The Keystone is the blue trace, Langston's TH-115 is the purple, white is his TH-118.

Are yours loaded with BC-18SW115-4?
What filter settings were you using?
Langston now has all B&C drivers in his TH118's.

The original TH118's were loaded with 18 sound drivers-but there were some issues with some of them-that were very "sparatic" in nature.

This only lasted a month or so-and then the switch to the B&C drivers (all the faulty drivers were replaced by Danley)-which have been working just fine-except when Langston decides to run a 14KW amp into clip into them-------OOPS----
 
#12
Re: 4 July Hi-Fi

How is the system powered and processed?

Amps are two Powersoft K-10 DSP. One for tops L/R and one for subs normal/delay. So all outputs are looking into nominal 2 Ohms. The plan is that the relatively small amp rack can live near the (typically) center stacked subs so that the speaker cables are short -- especially for the subs. I rewired the Danley inputs to use all 4 pins to utilize all the Cu in a 4 conductor cable. The Powersoft outputs come wired this way. 20 ft. (both ways) of 14/4 at 2 Ohms has .2 dB loss and a damping factor of 40 -- not a problem.

Now, on the settings for the SH-46s. I'll tell you what I used but also tell you that this is shoot-from-the-hip preliminary and based on sloppy measurements. I have (grandiose?) plans to do much more refined measurements over a range of angles and some optimized fitting. If and when I do I'll share the results. Listen at your own risk :)

SH-46 (2 each side)

high pass (crossover): 4th order LR, 90 Hz
high shelf: +8 db, 11.5 kHz
bell boost: +7.5 dB, Q = 1.9, 6.3 kHz
bell boost: +4 dB, Q = 4.3, 760 Hz
gain = 0 dB
delay = 0

TH-118 (4 in the middle)

high pass: 4th order BW, 25 Hz
low pass (crossover): 4th order LR, 90 Hz
gain = +4.6 dB
delay = 6.2 ms determined for this particular setup, additional 4 ms for forward end-fire pair
no polarity flip

--Frank
 
Jan 11, 2011
804
7
18
Florida
#13
Re: 4 July Hi-Fi

Langston now has all B&C drivers in his TH118's.

The original TH118's were loaded with 18 sound drivers-but there were some issues with some of them-that were very "sparatic" in nature.

This only lasted a month or so-and then the switch to the B&C drivers (all the faulty drivers were replaced by Danley)-which have been working just fine-except when Langston decides to run a 14KW amp into clip into them-------OOPS----
Yep, "smoke 'em if ya got 'em" ;^).

The old 2010 TH-118 spec sheet pictures a 15" speaker in the cabinet (doh), but the FR graph looks like Langston's from June 18, 2010.

The new 2012 TH-118 spec sheet still pictures a 18Sound woofer, and the exact same FR & impedance as the 2010 spec sheet, though the measurement date has been changed.
The picture has an 18Sound 18" not the BC 18SW115, which has split frame ribs.

Looking at Frank's TH-118 measurements, the non "sparatic" BC18SW115 appears to not go as low as the 18Sound version.
The 18sound NLW9000 has a lower FS, less Mms, and larger VAS, all of which (probably) result in a lower frequency response.
At any rate, with the differences noted, they certainly can't test identically.

Though the differences are not much, I'm sure you will want to retest the TH-118 with the current BC18SW115-4 to reflect the many changes in the cabinet's specifications for the sake of preserving DSL's reputation of honest specifications.

The original 18sound NLW9000 was rated at 1800W AES, 3600 Program, the replacement BC 18SW115-4 is rated 1700 & 3400W.
The NLW9000-4 has a DCR of only 2.5 ohms, while the BC18SW115-4 is 3.3 ohms, which will change the TH-118 sensitivity and impedance curve specifications.

All the 18Sound were not recalled, as you may remember from February of 2011:
http://forums.prosoundweb.com/index.php?topic=442.45;wap2

You might also consider (if you have not already) testing the less expensive ceramic magnet BC18TBW100 which was released since that discussion, it should have only around 1 dB less clean output (12mm Xmax compared to the 18SW115's 14), and slightly less power handling, for a slightly lower cost version of the TH-118 for those who need money more than the last dB.

Art
 

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Ivan Beaver

Graduate Student
Jan 11, 2011
2,300
6
0
Atlanta GA area
#14
Re: 4 July Hi-Fi

The old 2010 TH-118 spec sheet pictures a 15" speaker in the cabinet (doh), but the FR graph looks like Langston's from June 18, 2010.

The new 2012 TH-118 spec sheet still pictures a 18Sound woofer, and the exact same FR & impedance as the 2010 spec sheet, though the measurement date has been changed.
The picture has an 18Sound 18" not the BC 18SW115, which has split frame ribs.

Looking at Frank's TH-118 measurements, the non "sparatic" BC18SW115 appears to not go as low as the 18Sound version.
The 18sound NLW9000 has a lower FS, less Mms, and larger VAS, all of which (probably) result in a lower frequency response.
At any rate, with the differences noted, they certainly can't test identically.

Though the differences are not much, I'm sure you will want to retest the TH-118 with the current BC18SW115-4 to reflect the many changes in the cabinet's specifications for the sake of preserving DSL's reputation of honest specifications.

The original 18sound NLW9000 was rated at 1800W AES, 3600 Program, the replacement BC 18SW115-4 is rated 1700 & 3400W.
The NLW9000-4 has a DCR of only 2.5 ohms, while the BC18SW115-4 is 3.3 ohms, which will change the TH-118 sensitivity and impedance curve specifications.

All the 18Sound were not recalled, as you may remember from February of 2011:
Danley TH118 or TH212

You might also consider (if you have not already) testing the less expensive ceramic magnet BC18TBW100 which was released since that discussion, it should have only around 1 dB less clean output (12mm Xmax compared to the 18SW115's 14), and slightly less power handling, for a slightly lower cost version of the TH-118 for those who need money more than the last dB.

Art
To be totally honest, I do not remember when the original measurements/spec sheet were made-in relation to when the TH118 started being built. I can check/cross reference jobs etc-but it won't happen soon-as were are extremely busy over the next several weeks with some really important "stuff/projects" going on.

It is HIGHLY likely that the spec sheet was of the B&C driver-not the 18 sound. Rarely do we have a spec sheet at the time a product starts shipping. There are many people "in the know" who get/use products long before the spec sheet hits the streets (this is how we first found the issue with the 18 sound drivers). Not that many cabinets went out with the 18 sound drivers before we discovered a problem-luckily I was the one who found it on an install that baffled me for awhile. Then further testing in the shop with one of the defective drivers showed me what was going on. Other 18Sound drivers were just fine-as we had used in our initial testing of the product.

Early on is when we noticed the issues with SOME of the 18 sound drivers. Not all of them had the problem-so we replaced all the ones that had an issue.

I remember when swapping out drivers in the exact same physical cabinet and using the same measurement position (eliminating as many variables as possible) that the differences between the drivers was extremely minimal at best (we are talking 1/4 to 1/2 dB type stuff here-if I remember correctly). So as I stated earlier the CABINET is the biggest contributor to the overall response-the drivers are simply "pistons" pushing air.

Personally I would be a lot more concerned with manufacturers who do not provide any data or measurements or whose products can't come with within 10-15dB of stated specs. or whose "simple numbers" are 6-10dB off from their measured graphs-or whose prediction data has been greatly modified so that it doesn't show the "bad stuff" etc.

But maybe that is just me. EVERYBODY should be held to the same level/expectations-and not "given a free pass" just because of who they are.

Yes we want to be as accurate as possible-but you also have to consider driver to driver (of the same model number) variance. That can account for a dB or two in some cases. When we do a measurement-it is of a random cabinet-NOT picking through a bunch to find the best one. So the actual measurement could look a bit different (once you get down to that level) of the same model number.

Yes the data name details was changed on the response curve. That was in accordance with what YOU pointed out in the earlier thread-about watts vs volts. So I simply changed that part (as per your request) and the new date popped up.

I have yet to hear from anybody who says that the TH118 (or any of our products) are not performing as the spec sheet says.
 
Jan 11, 2011
804
7
18
Florida
#15
Re: 4 July Hi-Fi

To be totally honest, I do not remember when the original measurements/spec sheet were made-in relation to when the TH118 started being built. I can check/cross reference jobs etc-but it won't happen soon-as were are extremely busy over the next several weeks with some really important "stuff/projects" going on.

It is HIGHLY likely that the spec sheet was of the B&C driver-not the 18 sound. Rarely do we have a spec sheet at the time a product starts shipping. There are many people "in the know" who get/use products long before the spec sheet hits the streets (this is how we first found the issue with the 18 sound drivers). Not that many cabinets went out with the 18 sound drivers before we discovered a problem-luckily I was the one who found it on an install that baffled me for awhile. Then further testing in the shop with one of the defective drivers showed me what was going on. Other 18Sound drivers were just fine-as we had used in our initial testing of the product.
Yes the data name details was changed on the response curve. That was in accordance with what YOU pointed out in the earlier thread-about watts vs volts. So I simply changed that part (as per your request) and the new date popped up.
Ivan,

In light of the fact that you don't recall when the original measurements/spec sheet were made, and given the fact that the original DSL test date predates Langston's test date by some time, and Langston's tests (that I posted) were done using the 18Sound drivers, it seems more likely to me that the spec sheets reflect the 18sound driver, not the B&C.

The time line and the obvious rated power discrepancy (the spec is for the 18sound, not the B&C) simply does not support the original test being done with the current B&C drivers, and since no re-test has happened, it only seems logical that the spec sheet does not reflect the sensitivity and impedance curve of the current driver, even if the frequency response somehow remained identical, unlikely considering the TS parameter differences between the drivers.

Art
 
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Ivan Beaver

Graduate Student
Jan 11, 2011
2,300
6
0
Atlanta GA area
#16
Re: 4 July Hi-Fi

Ivan,

In light of the fact that you don't recall when the original measurements/spec sheet were made, and given the fact that the original DSL test date predates Langston's test date by some time, and Langston's tests (that I posted) were done using the 18Sound drivers, it seems more likely to me that the spec sheets reflect the 18sound driver, not the B&C.



Art
As I said earlier-not everybody was having issues. Just some. Langston had his TH118's for awhile before the drivers got changed out (I don't remember how long)-and if I remember correctly-he was not having any issues when they were changed-they were changed "just in case".

I am sorry this bothers you.
 
Jan 11, 2011
804
7
18
Florida
#17
Re: 4 July Hi-Fi

As I said earlier-not everybody was having issues. Just some. Langston had his TH118's for awhile before the drivers got changed out (I don't remember how long)-and if I remember correctly-he was not having any issues when they were changed-they were changed "just in case".

I am sorry this bothers you.
Ivan,

I am not bothered by the driver replacement, but it appears by the spec sheet that the cabinet was never retested with the replacement.

This issue was never addressed (other than subjectively) a year after the initial 18sound test.

Danley TH118 or TH212

If DSL can't be bothered to test the current driver and update the specifications to reflect the changes, it is no problem to me ;^).
Compared to stadium installs, this all must seem pretty trivial...

Art
 

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Ivan Beaver

Graduate Student
Jan 11, 2011
2,300
6
0
Atlanta GA area
#18
Re: 4 July Hi-Fi

Ivan,


Compared to stadium installs, this all must seem pretty trivial...

Art
While we have several double handfuls of arena and larger projects in the works right now-it takes lots of the onesy-twosy orders to keep a company in business.

It is not a matter of 'not being bothered", but rather that nobody else has an issue and the TH118 is our best selling sub-because of how well it works.

Taking time away from other projects (or finding the time) to update a graph that may only change just a tad (and not affect the usability any) -is just not high up on the list.

I guess it would be a lot easier if we did like other companies and just made up numbers-that the products can't actually do or they no idea where the numbers came from. That way it is much harder for people to hold you to them. Doesn't seem to bother other manufacturers----------------------------------------------
 
Jan 11, 2011
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Florida
#19
Re: 4 July Hi-Fi

Taking time away from other projects (or finding the time) to update a graph that may only change just a tad ...I guess it would be a lot easier if we did like other companies and just made up numbers..
Ivan,

Like you say, "Any complicated question can be easily answered by a Simple-Easy to understand- WRONG answer!"

Art
 

Bennett Prescott

Just This Guy, You Know?
Staff member
Jan 11, 2011
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#20
Re: 4 July Hi-Fi

This only lasted a month or so-and then the switch to the B&C drivers (all the faulty drivers were replaced by Danley)-which have been working just fine-except when Langston decides to run a 14KW amp into clip into them-------OOPS----
I thought he did that in the name of science? :lol: