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4313B
11-13-2013, 05:03 AM
S3900 BiWired

Courtesy of Greg Timbers.

4313B
11-13-2013, 05:07 AM
S4700 BiWired

Courtesy of Greg Timbers.

Mctwins
11-13-2013, 07:42 AM
Hallo!

Looks nice:applaud:

Is it measurerd in a anechoic chamber or in a ordinary room?

Why the strange freq response above 10kHz in both speakers?

dbx260 is a nice DSP:)

Mostlydiy
11-13-2013, 09:29 AM
Lovely! Waiting for the K2s9900 numbers :)

I appreciate the time you guys put in to this "DSP conversion project". Its a rather easy thing to try out when provided with these eq figures. Kudos!

/Mostly

Bobecca
11-13-2013, 10:01 AM
@4313B,

When you say(or G.T) biwired, how is it connected? Is there only one amp and bi-wire cable for left and right speaker or two amps for left and right speakers and separate cables from left and right out from respectively amp?

If one amp is used how does the crossover work? To me this is impossible!

Could you clarify?

Bobecca
11-13-2013, 10:09 AM
BTW, the dbx 260 is a great unit. If I could I would get my hands on a dbx4800, period:D

4313B
11-13-2013, 10:10 AM
http://manuals.harman.com/JBL/HOM/Technical%20Sheet/S3900%20ts.pdf

http://manuals.harman.com/JBL/HOM/Technical%20Sheet/S4700%20ts.pdf

Bobecca
11-13-2013, 10:13 AM
http://manuals.harman.com/JBL/HOM/Technical Sheet/S3900 ts.pdfhttp://manuals.harman.com/JBL/HOM/Technical Sheet/S4700 ts.pdf


:confused:, yes there is two binding post, or what do you mean?

EDIT! I get it now:p The crossover points is not used on the dbx, only the parametric filters, right;)

4313B
11-14-2013, 09:13 AM
:thmbsup:


Why the strange freq response above 10kHz in both speakers?UHF unhooked. The focus was on the LF and HF.


As one can see, this data is hot off the press. :)

As for the DD65000 and DD67000, they aren't finished yet.

bubbleboy76
11-14-2013, 10:45 AM
Will he do it for 4365 as well? Please please pleeeeaase!
I am really tempted to go active.

spkrman57
11-14-2013, 06:02 PM
Will he do it for 4365 as well? Please please pleeeeaase!
I am really tempted to go active.

But I think the 4365 has already been superceded with the Nd stuff.

I have 1501Fe's and would love to see the possibilities.

Ron

Bobecca
11-15-2013, 05:58 AM
:confused:, yes there is two binding post, or what do you mean?

EDIT! I get it now:p The crossover points is not used on the dbx, only the parametric filters, right;)

I have to correct myself here. I really dont understand how it is implemented in dbx260 or how the connection is done. What does the INPUT stands for, is it prePEQ or postPEQ?? I asume it is the prePEQ that is used here.

In the dbx260 it is not possible to have more than seven prePEQ(first and last is only shelving type of filter) and four postPEQ(on each output).

How is it possible to have 10 parametric settings on that provided chart(S4700)?

It can not be biwired in this config. It has to be two amps involved!

Am I missing something???????

4313B
11-15-2013, 08:45 AM
I have to correct myself here. I really dont understand how it is implemented in dbx260 or how the connection is done. What does the INPUT stands for, is it prePEQ or postPEQ?? I asume it is the prePEQ that is used here.

In the dbx260 it is not possible to have more than seven prePEQ(first and last is only shelving type of filter) and four postPEQ(on each output).

How is it possible to have 10 parametric settings on that provided chart(S4700)?

It can not be biwired in this config. It has to be two amps involved!

Am I missing something???????Ah! There might be symantics involved here. By "bi-wire", G.T. means that the passive networks are left in place and that the LF and HF inputs are used separately. One amp on the LF and one amp on the HF. The dbx comes before the LF and HF amps.

I've never looked at the dbx manual.

Mctwins
11-15-2013, 12:05 PM
:thmbsup:

UHF unhooked. The focus was on the LF and HF.


As one can see, this data is hot off the press. :)

As for the DD65000 and DD67000, they aren't finished yet.

Thanks, I realized it later:)

G.T can do a test with PA+ and JBL 4319, if he has the time:D

Mctwins
11-16-2013, 12:55 AM
Ah! There might be symantics involved here. By "bi-wire", G.T. means that the passive networks are left in place and that the LF and HF inputs are used separately. One amp on the LF and one amp on the HF. The dbx comes before the LF and HF amps.

I've never looked at the dbx manual.

Ok, the amp question has been answerd:applaud:

Still don't get it about the numbers of PEQ(10 total in S4700):confused: How did G.T do this??

Does he mix prePEQ and postPEQ together??

bubbleboy76
11-16-2013, 02:01 AM
Is the internal crossover not bypassed? Isn't that missing a large point of going active?

4313B
11-16-2013, 06:32 AM
Is the internal crossover not bypassed? Isn't that missing a large point of going active?The purpose of the exercise was to add delay and to arrive at true LR 24 filters, then evaluate the results. It was not to go full active and bi-amp either system. No one is advocating that anyone who owns an S3900 or S4700 run out and buy a dbx and a second amp. It just so happens that the exercise resulted in very positive changes. I have no idea where it all fits into the total equation, e.g. does two grand for a dbx and a second amp yield a greater bang for the buck than hooking up a single two thousand dollar amp?
Ok, the amp question has been answerd:applaud:

Still don't get it about the numbers of PEQ(10 total in S4700):confused: How did G.T do this??

Does he mix prePEQ and postPEQ together??I've never looked at the dbx manual. If one has to use pre and post to get ten then yes, that is what he did. No different than the Crown HD and M2. I have posted how the Crown HD and M2 were configured and they do indeed use pre and post. It has been mentioned that the problem with the dbx and the lesser Crowns is that there are not enough PEQ points to properly implement an in-room fully active setup.

grumpy
11-16-2013, 04:00 PM
Buy two... go digital out on the first and digital in on the second, clocking them together?
(I'm just blowing smoke... can you even do that without cutting into their guts?)

Mr. Widget
11-16-2013, 05:24 PM
Buy two... go digital out on the first and digital in on the second, clocking them together?
(I'm just blowing smoke... can you even do that without cutting into their guts?)
What is it that you're smoking? ;)


Widget

grumpy
11-16-2013, 07:55 PM
Good question... I was thinking 4800/20 apparently, with digital I/O. :o:

pos
07-25-2014, 08:07 AM
So any follow-up on this project?
What about the E2 ? :D

The 4430 for example would clearly deserve some DSP magic...
David Smith recently said something along those lines on the diyaudio forum, more specifically about the 2344 and how good it would become if properly EQed.

pos
07-25-2014, 08:43 AM
Found the post:
http://www.diyaudio.com/forums/multi-way/240737-jbl-horn-11.html#post3599353


If cheap DSP is a given then maybe the old 2344 was the perfect horn. It certainly had the most ideal polars and d.i. Axial response was an exact copy of the driver's power response. There were no bad angles response wise. The one issue was low end roughness that could easily be handled with a bit of DSP.

Just sayin...

David

4313B
07-25-2014, 10:24 AM
So any follow-up on this project?
What about the E2 ? :D

The 4430 for example would clearly deserve some DSP magic...
David Smith recently said something along those lines on the diyaudio forum, more specifically about the 2344 and how good it would become if properly EQed.


Found the post:
http://www.diyaudio.com/forums/multi-way/240737-jbl-horn-11.html#post3599353The E2 arguably deserves the IT HD Crowns as opposed to the DBX.

I've always thought the 2344's were great, never did find any Be diaphragms to bolt to them though.

4313B
10-07-2014, 04:03 PM
What about the E2 ? "I havenít gotten back into working with the DBX or with any other speaker models. I am using an AllDSP model PLP226 Signature. It is basically 2 in and 6 out which works for my Tri-amp system I am not using the UHF at all. I actually did my design with my speakers in place in my living room. I put in a 4 th order LR crossover target (750 Theoretical) and made 4 mic measurements of each of my woofers and HF units. Averaged the 4 positions for each transducer and used those 6 curves as the transducer measurements. I then applied the necessary crossover slopes and frequencies to get the acoustic measurement to match the electrical target as closely as possible. It doesnít matter what electronic slope and frequency is used so long as the actual acoustic response is close.

Next I applied the necessary EQ to get the crossover slopes tuned in. Once done, I turned everything back on and made a Left (or Right) channel measurement using the same 4 mic positions averaged. The summing came out nearly perfect, as it should. I did the time delay by choosing one of the mic positions that gave the smoothest curve through crossover and inverting the polarity on the HF. I adjusted the delay for the deepest and most symmetrical notch at crossover. Flip the phase and all goes flat again. Finally, I applied some global EQ to the entire system to clean up any remaining room of summing issues. It is very simple to do, but it takes forever due to the multiple measurements and repetitive nature of things. My results were awesome.

The DBX Driveline 260 can do the job nicely although it is a little limited in PEQ filters. You have to be pretty efficient. I am currently looking at other High End solutions which incorporate built-in Preamp functions so I can ditch my analog preamp. Among the contenders are the Ground Sound DCN28 and the DEQX HDP-4. All are pretty pricey. The DBX is cheap at about $1000."

ivica
10-09-2014, 01:33 AM
"I haven’t gotten back into working with the DBX or with any other speaker models. I am using an AllDSP model PLP226 Signature. It is basically 2 in and 6 out which works for my Tri-amp system I am not using the UHF at all. I actually did my design with my speakers in place in my living room. I put in a 4 th order LR crossover target (750 Theoretical) and made 4 mic measurements of each of my woofers and HF units. Averaged the 4 positions for each transducer and used those 6 curves as the transducer measurements. I then applied the necessary crossover slopes and frequencies to get the acoustic measurement to match the electrical target as closely as possible. It doesn’t matter what electronic slope and frequency is used so long as the actual acoustic response is close.

Next I applied the necessary EQ to get the crossover slopes tuned in. Once done, I turned everything back on and made a Left (or Right) channel measurement using the same 4 mic positions averaged. The summing came out nearly perfect, as it should. I did the time delay by choosing one of the mic positions that gave the smoothest curve through crossover and inverting the polarity on the HF. I adjusted the delay for the deepest and most symmetrical notch at crossover. Flip the phase and all goes flat again. Finally, I applied some global EQ to the entire system to clean up any remaining room of summing issues. It is very simple to do, but it takes forever due to the multiple measurements and repetitive nature of things. My results were awesome.

The DBX Driveline 260 can do the job nicely although it is a little limited in PEQ filters. You have to be pretty efficient. I am currently looking at other High End solutions which incorporate built-in Preamp functions so I can ditch my analog preamp. Among the contenders are the Ground Sound DCN28 and the DEQX HDP-4. All are pretty pricey. The DBX is cheap at about $1000."

Hi 4313B,

Have You any idea what are the mic positions : '...made 4 mic measurements of each of my woofers and HF units..."

Regards
ivica

grumpy
10-09-2014, 12:48 PM
Hi Ivica,

I am sure you still would prefer the answer from "the source", but I can recommend emulating the
locations where a pair of people's ears would likely be while listening ... roughly a 3ft wide window.

When setting up Titanium Dome's "250Ti" 4-way active system, -final- in-room measurement/adjustment
cycles were accomplished this way. This seemed to pass muster with the visiting audio giants that this
process was described to, followed by a bit of listening. Many other individual measurements were made,
but this last step helped to correlate listening experience to worthwhile adjustments. E.g., balancing in-situ
FR measurements between channels greatly enhanced imaging/sense of space.

I'd be happy to hear specific recommendations (and rationale) as well.

bubbleboy76
06-07-2015, 03:26 PM
I have to correct myself here. I really dont understand how it is implemented in dbx260 or how the connection is done. What does the INPUT stands for, is it prePEQ or postPEQ?? I asume it is the prePEQ that is used here.

In the dbx260 it is not possible to have more than seven prePEQ(first and last is only shelving type of filter) and four postPEQ(on each output).

How is it possible to have 10 parametric settings on that provided chart(S4700)?

It can not be biwired in this config. It has to be two amps involved!

Am I missing something???????

There are 6 notch-filters that can be used as reducing PEQs as well in the DBX 260.
So you have 7prepeq+2pre-shelf+6notch+4LF postpeq+4HFpostpeq+4UHFpostpeq to use.

bubbleboy76
06-29-2016, 05:33 PM
S4700 BiWired

Courtesy of Greg Timbers.

The delay-setting here, is it stated in time (ms)? Or distance?

(this great thread needs to be bumped now and then)

bubbleboy76
06-29-2016, 05:35 PM
"I haven’t gotten back into working with the DBX or with any other speaker models. I am using an AllDSP model PLP226 Signature. It is basically 2 in and 6 out which works for my Tri-amp system I am not using the UHF at all. I actually did my design with my speakers in place in my living room. I put in a 4 th order LR crossover target (750 Theoretical) and made 4 mic measurements of each of my woofers and HF units. Averaged the 4 positions for each transducer and used those 6 curves as the transducer measurements. I then applied the necessary crossover slopes and frequencies to get the acoustic measurement to match the electrical target as closely as possible. It doesn’t matter what electronic slope and frequency is used so long as the actual acoustic response is close.

Next I applied the necessary EQ to get the crossover slopes tuned in. Once done, I turned everything back on and made a Left (or Right) channel measurement using the same 4 mic positions averaged. The summing came out nearly perfect, as it should. I did the time delay by choosing one of the mic positions that gave the smoothest curve through crossover and inverting the polarity on the HF. I adjusted the delay for the deepest and most symmetrical notch at crossover. Flip the phase and all goes flat again. Finally, I applied some global EQ to the entire system to clean up any remaining room of summing issues. It is very simple to do, but it takes forever due to the multiple measurements and repetitive nature of things. My results were awesome.

The DBX Driveline 260 can do the job nicely although it is a little limited in PEQ filters. You have to be pretty efficient. I am currently looking at other High End solutions which incorporate built-in Preamp functions so I can ditch my analog preamp. Among the contenders are the Ground Sound DCN28 and the DEQX HDP-4. All are pretty pricey. The DBX is cheap at about $1000."

I think I will try this procedure on my newly procured 4429:s :)

I would also like to know which 4 mic positions he used. On the floor, etc?

1audiohack
06-30-2016, 09:53 PM
Sounds fun!

Barry.

boputnam
06-30-2016, 09:56 PM
I then applied the necessary crossover slopes and frequencies to get the acoustic measurement to match the electrical target as closely as possible. It doesnít matter what electronic slope and frequency is used so long as the actual acoustic response is close. There is is in a nutshell, sports fans. Genius in it's simplicity and correctness... :bouncy:

bubbleboy76
09-07-2016, 11:14 PM
"I haven’t gotten back into working with the DBX or with any other speaker models. I am using an AllDSP model PLP226 Signature. It is basically 2 in and 6 out which works for my Tri-amp system I am not using the UHF at all. I actually did my design with my speakers in place in my living room. I put in a 4 th order LR crossover target (750 Theoretical) and made 4 mic measurements of each of my woofers and HF units. Averaged the 4 positions for each transducer and used those 6 curves as the transducer measurements. I then applied the necessary crossover slopes and frequencies to get the acoustic measurement to match the electrical target as closely as possible. It doesn’t matter what electronic slope and frequency is used so long as the actual acoustic response is close.

Next I applied the necessary EQ to get the crossover slopes tuned in. Once done, I turned everything back on and made a Left (or Right) channel measurement using the same 4 mic positions averaged. The summing came out nearly perfect, as it should. I did the time delay by choosing one of the mic positions that gave the smoothest curve through crossover and inverting the polarity on the HF. I adjusted the delay for the deepest and most symmetrical notch at crossover. Flip the phase and all goes flat again. Finally, I applied some global EQ to the entire system to clean up any remaining room of summing issues. It is very simple to do, but it takes forever due to the multiple measurements and repetitive nature of things. My results were awesome.

The DBX Driveline 260 can do the job nicely although it is a little limited in PEQ filters. You have to be pretty efficient. I am currently looking at other High End solutions which incorporate built-in Preamp functions so I can ditch my analog preamp. Among the contenders are the Ground Sound DCN28 and the DEQX HDP-4. All are pretty pricey. The DBX is cheap at about $1000."

Anyone having a guess which kind of mic-positions Greg used here?
I would like to try this procedure.
Mic close to speaker, or at listening positions?
Mic at ear levels, or ground-plane?
EXACT same mic-positions all the iterations?

NWCgrad
09-12-2016, 05:50 AM
That would be great information. I will be fine tuning a large DIY three-way speaker in next couple of weeks. I was planning on hauling them outdoors for the initial measurements, but they will be very heavy and if in room is good enough for an engineer the caliber of GT it is more than good enough for a geneticist like myself.

Does anyone know of any useful references for setting up digital XO's and EQ? The D'Appolito text on measuring loudspeakers is about all I can find. I know Self has a giant book on digital crossover design, but I believe it is for the development of the device and not its implementation.

boputnam
09-13-2016, 12:34 PM
1) Anyone having a guess which kind of mic-positions Greg used here?
I would like to try this procedure.
2) Mic close to speaker, or at listening positions?
3) Mic at ear levels, or ground-plane?
4) EXACT same mic-positions all the iterations?

1) Use a quality measurement mic which comes with a response curve measure for it. Earthworks M30 is suitable.
2) I prefer measuring where the listening will be done. In the field, we move the mic(s) around to different locations and average. In the home, I fix one position - the sweet spot - and pin it down. The adjacent positions won't be so different (unless you have really beamy horns).
3) Ibid
4) Ibid.


That would be great information. I will be fine tuning a large DIY three-way speaker in next couple of weeks. I was planning on hauling them outdoors for the initial measurements, but they will be very heavy and if in room is good enough for an engineer the caliber of GT it is more than good enough for a geneticist like myself.

Does anyone know of any useful references for setting up digital XO's and EQ? The D'Appolito text on measuring loudspeakers is about all I can find. I know Self has a giant book on digital crossover design, but I believe it is for the development of the device and not its implementation.For a three-way that is tri-amped, you must do each band pass separately. DO ONLY ONE SIDE OF THE SYSTEM; copy to the other side. However, first, establish your delay(s). The LF will have the most retarded acoustic arrival time due to the LPF. Measure it's impulse and delay the other band passes to match. Then, tune each band pass separately, striving for flat reproduction of Pink noise. Then, open all band passes and measure the overall reproduction of Pink. Look at the response at the crossover points - if you see summing or subtraction (cancellation) try toggling the phase for one band pass or another. Do not worry your little head about this - just listen to the result and how the response curve looks.

Have fun.

NWCgrad
09-14-2016, 07:33 AM
1) Use a quality measurement mic which comes with a response curve measure for it. Earthworks M30 is suitable.
2) I prefer measuring where the listening will be done. In the field, we move the mic(s) around to different locations and average. In the home, I fix one position - the sweet spot - and pin it down. The adjacent positions won't be so different (unless you have really beamy horns).
3) Ibid
4) Ibid.

For a three-way that is tri-amped, you must do each band pass separately. DO ONLY ONE SIDE OF THE SYSTEM; copy to the other side. However, first, establish your delay(s). The LF will have the most retarded acoustic arrival time due to the LPF. Measure it's impulse and delay the other band passes to match. Then, tune each band pass separately, striving for flat reproduction of Pink noise. Then, open all band passes and measure the overall reproduction of Pink. Look at the response at the crossover points - if you see summing or subtraction (cancellation) try toggling the phase for one band pass or another. Do not worry your little head about this - just listen to the result and how the response curve looks.

Have fun.

Thanks for the advice...it should be a fun adventure getting the big beast dialed in for optimal performance. Will start off bi-amped (have passive XO for the HF/MF), next year will upgrade my Peavey VSX to the DBX Venu360 and go fully active. The Peavey has some weird software controlled gain structure that induces noise if used to attenuate the signal for the HF unit. Makes it a poor choice for this application, but it is what it is.:crying: