Which Components Should I Use?

[Wonderboy]

Hi Guys,

I have been accumulating some JBL components over the years to maybe one day build a JBL (the best!) speaker system. I have done a bit of testing and think I have the correct combination but I do not have the Knowledge or experience with these components and speaker building as some of you guys do. I figured before I go ahead with my project I would list what components I have for you guys to see and see if you agree or not with what I plan on doing. I will list number of components and their model number,here goes:
Drivers:

2-2404H (ferrite? the newer magnet design)
3-2405 16 ohm (J?) Alnico
1-2405H ferrite (need diaphragm)

1-2426J
1-2425H
4-2425J (two of them have a 2327 attached)
2-2470 16 ohm Alnico (with 183-309's attached)
1-2445J (need diaphragm)
2-2482 16 ohm Alnico (with phenolic diaphragms)

2-2118J
2-2012H

2-2226J
2-2225H

Horns:
1-2370
5-2370A
2-2386
2-2380A
1-2397 (with 2328 attached)
1-2309
1-231? last number is missing Accoustic Lens (is big and attached to 2309)

Crossovers:
4-3110A

Miss.
1-Kitchen Sink (wave guide):applaud:

The components I have decided to use per side (well up to this point) is:
1-2405
1-2425 with 2370A
1-2012
1-2226

These speakers will be used with a domestic home theater receiver, these speakers will be the front left and right. I was thinking (if at all possbile) to split the signal coming out of the receiver (for eg. to the left speaker), take one side of the split signal and with resistors bring it down to line level, plug it into a Peavey IA 10/4 Interface Amplifier (I am using one now for my subs) then into an electronic Xover then into a power amp to power the 2226's. The other side of the split signal will power the other three components. I am reading up on how to make Xovers, I have made some simple ones in the past no more than second order, I'm new to this and my knowledge of electronics is not that great. I have the 3110A's but they cross over at 800Hz so I figured I could not use them?

I also plan on building a center channel using the 2397 with either the 2445 (with new diaphragm, alum, titanuim or other?) or maybe a 2482 with the phenolic, I hear they were designed for voice or midrange and there is a lot of that content in a HT center channel? Along with the horn maybe the 2118s with a 2405?

So there you have it, do you think I am on the right track?

Kevin.

[SMKSoundPro]

Wow! That's quite a list.

If you are going for a 4-way:

2235
2012
2425/2370a
2405

Jbl did it, and it works. Others may question the choice of 2012.

Or if 3-way:

2235
3110a xover
2425/2370a
3106 xover
2405

Looks like an L300, doesn't it.

Or if 2-way:

1-2235
1-2425/ 2370a
1-3110a xover

Or if high output Rock and Roll:

2- 2226
1- 3110a xover
1- 2445/ 2309 horn w/2310 serpentine lense
1- 3106 xover
1- 2405 for sizzle.

In other words:

You have many different parts. Make a plan for the L & R main speakers; a plan for the center channel; and if you're doing a single or double sub...then do it.

Sell off the other parts and never look back!

Many DIY guys are doing the same thing and always looking for parts. Get what you need and sell the other stuff to the other DIY guys.

And above all...

Keep it simple!!!


Scotty.

[SMKSoundPro]

Hi Guys,
Horns:
1-2370
5-2370A
2-2386
2-2380A
1-2397 (with 2328 attached)
1-2309
1-2310 last number is missing Accoustic Lens (is big and attached to 2309)

Kevin.

see correction

[Wonderboy]

Thanks for the input Scotty! I am trying to keep it simple, when I first came on this forum with my crazy ideas (Drew Daniels type of system) I was full of piss and vinegar to make this super powerful, blow you away system (one of my buddies is nuts over heavy rock bands from the 80's so I guess I wanted to impress him), but after doing some testing of the drivers together, I realized that "less is more" (got that from a man of experience on this forum). So I down sized my vision to reality and what really works. That's a good plan to sell what I don't use but I am a bit of a pack rat and figure somewhere down the line I might want to build another speaker or two so I will most likely hang onto them. (pass them onto my grand kids,ha!)

The 2235 you mention, I guess with it's number it came out after the 2226? What model was the four way system that JBL came out with that is similar to my design? Was it the 4344 monitor?

Kevin.

P.S. Thanks for filling in the last digit of the lens.:)

[johnaec]

The components I have decided to use per side (well up to this point) is:
1-2405
1-2425 with 2370A
1-2012
1-2226
That combination of drivers looks OK, but you may have problems getting passive crossovers lined up easily. What I'd do is use a passive only for the VHF 2405, around 7K or 8K, and use an active 3-way crossover for the rest, each range with its own amp. Of course, you'll need some sort of EQ with that, looking at the different response characteristics of the different drivers. But I think you could get it sounding fairly good, and capable of prodigious, (sp?), output if desired.

John

[Wonderboy]

Thanks for the input Johnaec. I kind of really wanted to avoid active filtering except for the mid-bass (2226's). Previously I designed another system using (God forbid) vintage Tannoy driver's along with a mix of planar mids and tweeters using an all active crossover system and I had nothing but trouble, ground noise, hum, buzz etc. I had to scrap the whole thing. I also don't have the cash for more amps, I have the active crossovers though, from that same system. Maybe later I could give it a try, from all I have read, active is the way to go! As far as super high sp levels, I myself am getting to old for that and would like to keep my hearing, when my buddy comes over, I have these cool little foam ear plugs I roll up and insert them into my ears, he does not even see them:).

Thanks again.

Kevin.

[Robh3606]

Hello Kevin

The driver components in a 4344 are a 2235/2122/2425 on a 2307/2405.
One advantage is we have equivalent passive networks, thanks to 4313, for that driver combo. If you want to go passive you are going to have to work out the networks for whatever combo you decide on. Active will work but you are going to need an EQ to help unless you go with a digital speaker management system.

If you want sub 40Hz bass in your mains to use them as stand alone stereo music speakers a 2235 would be a better woofer. If you are going to use a sub for them you might want to use a 12" like a 2206 and forget the lower midrange driver.

For HT L/R are not as important as the center. For stereo obviously the mains really count. How are you going to be using this system most??

Rob:)

[Wonderboy]

Hi Rob, thanks for the reply. I think I will have to attempt to work out a passive crossover network, at least give it a try. I do have a Behringer DSP unit, had it for years not even opened yet! Thing is, with a domestic system it is RCA jacks and the pro stuff is XLR so it's a real pain. I had a couple JBL 12" mid-woofers and ended up giving them to my "buddy" along with a couple 2370A's but I kept the JBL 2425's for myself and installed a couple of Eminence drivers instead, he was happy with the sound he got.

This system will be 99.9% home theater, so the center channel rules. The reason I really almost have to use the 2012's is that these are the only units I bought brand new and paid FULL price for, two for $700.00, all the rest of the drivers and horns I got on ebay or cheap from guys I know. Did you see my other question on which driver to use on a HT center channel?

Thanks Rob,

Kevin.

[Robh3606]

Hello Kevin

You know the bottom line is you want something you will be happy with. 4 ways are a PITA to get right. It seems you have tried DIY with Tannoys and it didn't work out. It is always easier to start with a known system than to start cold with a driver set with no baseline. With the driver combo's you have available there are plenty that can work as other have pointed out. I would stick to known combinations first and work from there if you feel the need.

For my center I use a cloned Urei 811C monitor. To me the vocals are paramount and a time aligned coax driver works, suites my needs just fine and covers the required range using a sub.

Rob:)

[Baron030]

Quoted by Kevin:
The components I have decided to use per side (well up to this point) is:
1-2405
1-2425 with 2370A
1-2012
1-2226


Hi Kevin
If you really want to go with these drivers then I would suggest going with either an active 3-way or 4-way electronic crossover network.
Johnaec is right about possibly using a passive crossover for the 2405 driver and an electronic 3-way for the rest.
Since, the high frequency drivers are much more efficient.
The power requirements for these are about a tenth of what is required for the lower frequency drivers.

In my own system, I like the 2226 drivers for their punchy bass.
But, their response really does falls off below 40Hz.
And from what I read, the 2235 will go almost another octave lower.
So, you should take that into account in your own design considerations.
And ask yourself is that lowest octave important to you or not?

Now, I know that in my own case.
That if at some point, I should start feeling bass deprived for that bottom octave.
I can always take two 2242s, and call my doctor in the morning.
Now, if I could just find the room for two Widget boxes…:D

The 2012H Maximum Output 250mm midrange/mid-bass does have it challenges.
The 2012 driver has a rising on-axis response that does require some EQ for it to sound right.
In my own system, I use a passive parallel trap circuit between a crown K1 and the 2012H driver to flatten the response over a 300 to 1200Hz range.

Here is a link to my 2012 passive EQ circuit: http://audioheritage.org/vbulletin/showthread.php?t=20823 (http://audioheritage.org/vbulletin/showthread.php?t=20823)

Unfortunately, I don’t think that this simple parallel trap circuit could be added to a passive crossover network without other major modification.
So, it’s really only a solution for systems that are using active crossover networks.

And as far as the 2425/2370A combination and the 2405 drivers are concerned, there have been some posting covering this ground.
So, there are passive crossover network solutions for these drivers.

Good luck with your project,
Baron030:)

[Doc Mark]

Hello, Baron030, and All,

This has been an interesting thread, as are many here at LH! Baron030, once again, you have answered a good question for me, even though it was actually unasked! Thanks, my Friend!! I've been wondering how, when I eventually get time for all this, I would incorporate the subwoofer I wish to build with a planned 4-way system, using the Ashly XR-4001 electronic crossover that I recently bought. Your solution was easy, elegant, and so simple that it never occurred to me: use a good passive crossover for the 2405's!!! :blink::applaud::D:bouncy: Thanks, very much for that tip, as it obviates one more little niggling problem, and I've filed it away in my system plans!! Take care, and God Bless!

Every Good Wish,
Doc

[Wonderboy]

Well Rob I hear what you're saying, I know I will be going out on a limb but I really have my heart set on a four way system and I know if I don't give it a go I know I won't be happy, so I guess I am the type that has to learn from my mistakes. The Tannoy thing was a pretty good sounding system but it was the bad grounding noises that made me pack it in. I am now a little leary of a set up of power amps and an active crossover, it could have also been a defect in the power amps I was useing, it's a long story.

Baron030 has given me hope that maybe I can make the drivers I have work. Now that I think of it, I do have three power amps I could use, I knew I had the one older Yorkville 3000 but I have a Bryston 4B-ST along with a cheaper Kenwood amp somewhere in the back of the closet:blink:. Baron030 seems pretty familiar with the 2012 and has even developed a passive EQ circuit for it. Baron if you are reading this, that picture of your speakers under your name when you post, what drivers and horns are those? That looks like exactly what I want to build, I have a couple of 2380a horns here I prefered to use over the 2370a's.

Kevin

[Baron030]

Hi Kevin

My system uses the following JBL components: 2226H, 2012H, 2382a/2446H, and a 2405H.
If you do a search on my old posting, you should find several things that will be helpful for your own DIY project.

Here is a link to the posting that describes my system:
http://audioheritage.org/vbulletin/showthread.php?t=11664

Baron030:)

[Robh3606]

I know if I don't give it a go I know I won't be happy, so I guess I am the type that has to learn from my mistakes.

Well that's a good thing what is the worst thing that can happen?? What tools do you have?? You are going to need some kind of basic measurement system and some design software for the crossover. Do you have anything now??

Rob:)

[Wonderboy]

Thanks Baron, I will check it out!

Well Rob to be honest with you I'm not much of an electronics guy, but I try hard. The way I have been testing my speakers in the past is with a good old fashioned (modified) Radio Shack SPL meter and a CD with many freq. test tones, from about 10Hz to 20kHz and a pen and paper. After so many tests, I transfer the data to graph paper to give me an idea of the drivers freq. response. (is that 'old school' or what?)

On my last post I mentioned I might try to go all active, well except for the VHF but not a hundred percent sure. I figured I could use Baron's EQ and all would be fine, I would give it a listen and if it sounds good, hey I'm happy but I guess a measurement test would be good too but I think you electronic's guy's are more into that and I guess I don't blame you (my son is in university for Engineering, I can relate) but I give a lot of credit to my ears. I have this older model Behringer DSP 8024 unit ( new in box, not even opened), I think it has the capabilities to measure my system, I bought a mic. to go with it, it has "room correction" features.

I think at the moment before I go any further, the first step would be to see if I can get the output signal from my HT receiver down to line level and see if I can get it to work with my Rane electronic Xover and amps, if not, it's passive all the way, could be scary! (and frustrating :banghead: )

Kev.

[Wonderboy]

Hmmm, well I just spent at least four hours trying different set ups, tweeters, amps, passive or active etc. I have come to the conclusion I would like to keep it as simple as possible (well, except for the fact I'm stuck on a four way system and using the 2012:)). I know what I plan to do will not go over to well with guys that are really into measurements and doing it by the book but if it works for me and I am happy what can I say. I have thrown my Radio Shack SPL meter out the window, it was modified years ago to be more sensitive to bass freqs. when I made my insane subs and now find it is not accurate for the higher ranges. So really now I have no test equipment, except my ears. (and I'm going deaf from testing, lol!)

I have decided to go with the 2370a horn like I mentioned earlier, I was having second thoughts and was thinking of switching over to the 2380a but after doing some serious listening and comparisons I'll stick with the 2370a's. Mind you, I was using the 2380a's with the 2482 driver and a phenolic diaphragm :barf:they did not sound good at all for music. So, my plan is to bi-amp the system, a separate power amp for the 2226's and another amp for the other three drivers, the 2012, 2425 and the 2405. I already have crossovers for the 2405 and the 2425's so really the only thing left I really need is a crossover design for the 2012 mid-bass driver. Baron030 suggested a parallel trap circuit for an active crossover to level out the response and get rid of the 1kHz spike but is there a way to do it passsive? I was thinking of crossing the 2012 with a high pass filter around 300Hz, 12dB per octave and a low pass around 1.2kHz, 12dB per octave, how does that sound?

Kevin.

[Ian Mackenzie]

Hi Kevin,

I recall this was mentioned in a post recently. Something like 1.5 mh will flatten the rising response of the 2012.

It is very difficult to make recomendations without actual hard data from measurements. Stuff like baffle step compensation and more to the point how the 2012 mates with your horn of choice is critical.

You cannot design a crossover with an RTA or a sound level meter unless you have a lot of experience with a particular drivers you plan to use.

If it were my with such a fantastic driver I would invest in the Woofer tester (speaker version) that measures proper gated impulse responses, assists with crossover calculatiions and a host of other great stuff. Its around $600-700.

This may sound a lot but you will never look back. Trust me.:).

Ian

[Baron030]

Hi Kevin

I will say this again. I really don't think that my parallel trap circuit can be added to the low pass section of a passive crossover network. It is really only a solution for active crossover systems.

And I think Ian Mackenzie might be remembering one of first attempts at flattening the 2012H with a 1.5mH coil. The 1.5mh coil trick did work, but it was only good for a very narrow frequency range and I used it with my Ashly. I have found by switching to a parallel trap circuit. That it works a whole lot better, over a wider frequency range, and with less insertion losses as well.

Now, having said all that, maybe I can throw out some ideas that might be helpful. If the low pass section of the 1.2 KHz crossover network had a low Q. Like a Linkwitz-Riley curve for example, then maybe some of the 2012s rising response could be compensated for. We are talking about some kind of an asymmetric crossover network here. And then, hopefully the network has enough series impedance to be able to really limit the current going to the 2012 at above 500Hz. In which case a series notch filter could be added to the circuit across the 2012 voice coil. This could take a really big bite out of that nasty 1,000Hz peak that the 2012 has. And I would think that maybe a third order network might be better then a second order network. There are some large peaks in the 2-3 KHz range. And a higher order filter would do a better job of kill them off.

Unfortunately, I don't have any crossover design software. So, I really can't help much in the crossover design. You see all of my attempts at making passive 2012 EQ circuits are all based on the trial and error method. And that is a very slow process. I can’t tell you how many hours I have put into building and mostly testing that very simple 2012 corrector circuit.

But, I could generate some response measurements of both my left and right 2012H drivers using CLIO 7.10 LITE. And maybe, that could come in handy…:D

Baron030:)

[johnaec]

I've also got a new pair of 2012H I'm debating crossing over to 2447J 1.5" drivers w/2381 horns, so I've been watching this with great interest. I need to see if I can move the crossover below 1K with this combination. BTW - crossover is Ashly XR4001.

John

[Zilch]

Get the 8024 running and learn how to use it..... :yes:

[4313B]

But, I could generate some response measurements of both my left and right 2012H drivers using CLIO 7.10 LITE. And maybe, that could come in handy…:D Post the response curve data file and the impedance curve data file so others here can pick them up and run with them if so inclined. Save the data with maximum points and set the phase to minimum as I showed in another thread.

There are other considerations such as what baffle is the driver on and what is the voice coil x, y, z orientation as well as the mic distance and drive voltage but that's out of scope in this particular instance.

[Wonderboy]

Hey Guys,

Thanks for the advice. Maybe I should just take Johnaec's route and cross the 2012 under the 1kHz with a third order? Actually at the moment the 2425's are crossed over at 800Hz, second order, but that might be cutting it a little close eh? I'm not sure how much overlap is needed at crossover points etc. Also I read somewhere that with a second order crossover in a three way or more system the polarity should be switched on one of the drivers to compensate for 180 degree phase shift? (something like that, not sure if I remembered it correctly). I was just reading in The Loudspeaker Design Cookbook, the author suggests possibly using a "T" bandpass topology that had been presented in Speaker Builder 2/87 for passive three way networks, is anyone familiar with this?

Thanks for the advice on the woofer tester Ian Mackenzie, at the moment I don't have that much money to spend. I think I saw a woofer tester for sale at Parts Express.com, not sure of the price or if that is what you are talking about? A week or two ago I read a whole bunch of your posts on your "Building the 4345/4344" found it very interesting, well done!

I think Zilch had some good advice for me, get the DSP 8024 up and running, I mentioned I had one earlier and was so hung up on my Radio Shack meter the DSP slipped my mind. I have had the unit since about 2003, think it's time to open it and get into it, not sure if I will be able to fit it in to my system though. My system is pretty domestic rather than pro audio but as soon as I post this thread, I will head down to the basement and dig it out and open the bloody box and get reading!:D

Baron030 go ahead and generate some response measurements for the 2012 if you feel up to it, but do not go to a lot of trouble for me but some of the other guys might like to see them, as mentioned by 4313B.

Another idea is, if I was to replace the phenolic diaphragms in the 2482's with aluminum or titanium or what ever, along with the 2380a horns, that might make them sound better and enable me to cross the horns lower (compared to the 2425s) as well as the 2012, further from the 1kHz region. Or is it the phenolic diaphragms that allow that driver to go that low?

What I don't understand is why would JBL construct a midrange/low-frequency speaker with all these peaks and problems, or did they design it for another application. In the Technical Notes for the 2012H, Volume 1, Number 24 it describes the "Desired" Performance Features of this driver, '#1' on the list it states: "1. Extended power response;rising axial response" they say it is "desired", or is that not the same as 'freq. response'? (please excuse my ignorance:blink:)

Kevin.

[Baron030]

Hello to All
Well, it looks like this is kicking up some 2012 driver interest around here. I will be happy to post the response and impedance curve data files, so that anyone here can pick them up and run with it. But, with Thanksgiving coming up soon, it might take me few days to compose a comprehensive posting with as accurate data as possible in it. So, just be patient here.

Hi Johnaec
I am using a 1.2 KHz. crossover point with my 2382a/2446h combination. And the reason why has a lot more to do with the 2382a low frequency roll-off then anything with the 2012. In comparing the 2381 to the 2382, it looks like you can go lower then I sure can. But, just lowering the crossover point is not going to be the quick fix to the rising response of the 2012H. I still think you need some 2012 EQ in the mix to make it all work right. The peak in the response really does gain +6db from about 500Hz to a 1 KHz. So, even a 4th order crossover will not fix this problem alone.

For anyone planning on using a passive crossover, I really do think that there is a relatively simple solution out there. It's just coming up with the correct component values that will be the hard part. Be it a 2nd or 3rd order crossover, I still think a series notch filter might be a good place to start. Maybe the schematic pictured will help explain what I am thinking about. And here are a few of my series notch filter assumptions. The series notch filter will need to resonate at 1 KHz. And if it is set to resonate below 1 KHz, then it will create a dip in the response at about 500Hz. And if it set too high, then it will miss the peak and not do its job. And “R1” value will most certainly need to be less then 8 ohms to provide the necessary amount of attenuation at 1 KHz. But, what I don't know is the Q value of the notch. These are the “C3” and “L3” values. If the Q is set too low, then there will be a big dip in the response at about 500Hz. And if the Q is set too high, then the single big peak will be replaced with two smaller ones and the response will not be as smooth as it could be. And I would also think that the “C3” and “L3” values will also vary depending on the selected crossover frequency. So, picking the correct series notch filter values will involve some trade offs.

Baron030:)

[johnaec]

But, just lowering the crossover point is not going to be the quick fix to the rising response of the 2012H. I still think you need some 2012 EQ in the mix to make it all work right.I've already determined I'll be using the Ashly XR4001 4-way active crossover in my case, and resigned myself to the fact I'll also hopefully just need a parametric EQ to smooth out the response, but may also have to include a 1/3 octave graphic EQ. The EQ's will be digital, while the Ashly is analog. Thank heaven for the low noise/distortion of most modern components, though the phase issues I'll be dealing with might become interesting.

What I'd really like to sew things together is an all in one 2-in 8-out digital signal processor that didn't cost an arm and a leg...

Of course - getting everything to work passive would be fantastic - 'too bad it's not practical to design passive with all the components instantly adjustable, like in the digital domain...

Either way, I'll be following this discussion with great interest.

John

[Ian Mackenzie]

Perhaps something more simple.

I messed with for an hour using a model of the 2012H and edited the response reasonable closely.

The upper response is purely resistive.

That is good for the driver but hard for crossover design in this case. The peaks from JBL data are at 3 and 5 khertz. The cone exhibits beaming at the onset of 1000 hertz.

Therefore a target crossover point of 1000-1500 hertz for domestic use is desireable.

Juggling a 2nd a order L / C network I got a 18 db slope at 1100 hertz. This assumes a given seal volume of around 10 litres.

In the end I found 1.38 Mh and 49uf have a nice curve that matches a 18 db low pass slope closely

[Baron030]

Hi Ian

This is very interesting and your timing could not be better. Since, I was thinking of running some more CLIO tests on my 2012H drivers anyways and posting the results here. I could also test something that is very close to your crossover suggestion. I have a pair of 1.50mH 0.23 ohm Jantzen foil air coils just sitting in a box with a big bunch solen caps. For testing purposes, I would not want to unwind these expensive coils down to 1.38mh. But, I could very quickly test a crossover circuit that would be very close to your design. It will be interesting to see the results. Assuming a 1.50mH coil, what cap value do you think I should try this test with?


Baron030:)

[Ian Mackenzie]

A few things,

This is only a model a made while munching my favourite pasta.

Second, the actual values are very critical to within 2 %.

A bit of this way and that and it turns to shit.

Its was just an indication of what you can do by manipulating the filter values in relation to the characteristics of a given driver.

The people at JBL are jab hands at this if you look at their networks.

But is not trivial and you might have several attempts following actual auditions.

Before going any further we need data of the actual measured driver

You really need to spend time getting this right with Clio and fed the data into a package like Soundeasy or LEAP Crossoevr Shop

Its not a Quick and Dirty RTA job on such a nice driver.

[Zilch]

Slander! :biting:

[And gratuitous, to boot.... :p ]

[Baron030]

Hi John
As an owner of an Ashly XR4001, I have to say that you have great taste in electronic crossovers networks. I love my Ashly. But, don't resign yourself just yet into thinking that a parametric EQ is required to smooth out the 2012H. Go back and take another look at my simple LRC circuit solution for use with active crossover networks. Ok, there are some here that will be quick to point out that a wavy 3 to 4 db peak to valley response isn't all that great. But, actually it does sound pretty good in my apartment. And I have been toying around with some ideas that could improve upon that simple circuit. In other words, this tread could start to get really interesting.

Hi Ian
I fully understand exactly what you are saying. Probably a hell of a lot more then most people around here. And yes, I will be spending a lot of time making sure that my CLIO measurements as accurate as possible before posting them here.

Maybe, I should look into buying a software package like Soundeasy. Wait a minute, I have been here before.
This is one of those red pill, blue pill decisions. As in, "You take the blue pill, the story ends, you wake up in your bed, and believe whatever you want to believe. You take the red pill, you stay in Wonderland, and I show you just how deep the rabbit hole goes."

You see I took that red pill, bought CLIO, and I now I am finding out just how deep the rabbit hole goes.

Baron030:)
There is no spoon....

[Ian Mackenzie]

I have come to the conclusion I would like to keep it as simple as possible (well, except for the fact I'm stuck on a four way system and using the 2012
I was thinking of crossing the 2012 with a high pass filter around 300Hz, 12dB per octave and a low pass around 1.2kHz, 12dB per octave, how does that sound?

Kevin.


Hi Kevin,

Sounds like a plan,

The peaky response is not such an issue if you intend to crossover from 1.2 - 1.6 khertz, I recommend a careful examination of the JBL data sheet regards loading the 2012 and setup. (the operating range is up to 1.6 khertz).

You may also like to consider the 2397 horns with the 2445 driver.
If you have $1100 to spare or want to trade other drivers I can steer you in the direction of some nice S/H 2 inch Tad 4001's (pair) available in the USA

The 2012 has very low power compression and very low distortion so it should be a nice match with the 2226 woofers. You can add some mild LF boost to the 2226 to help balance the system overall.

[Wonderboy]

Hello Ian

I'm glad you approve of my using the 2012 and the 2226 together. The "peaky response" of the 2012 has generated a lot of interest on this thread, it's been kinda cool watching you guys go at it.

You are not the first to suggest going with three 2397 horns, Mr. Widget suggested the same earlier on another thread. Guess it makes good sense to use the same horns in the front on a HT system, to keep the timbre etc. the same. These 2397 horns seem hard to come by, guess there is not to many around. Personally, I like the look of those nice wooden horns, like the one in your picture of the speaker on the left that comes up when you make a post. I like wood, to me it's kinda like eating "comfort food" like mashed potatoes, but instead it's "comfort for the eyes" guess that must be instilled in us from back in the days before man invented concrete and plastic:). Anyhow, I'm getting off topic, typical me:blah: (to much coffee), those S/H 2" TAD 4001's sound interesting and expensive, they must be good, are they not made by Pioneer?

Kevin.

[Wonderboy]

Hi Ian

I was just wondering, with your measurements a few posts earlier, you achieved an 18dB slope with a second order xover, is that common?

Kevin.

[Ian Mackenzie]

Because I am a Time Lord I can pull those tricks.

(Its has to do with the Q of the filter and its interaction with the driver natural response. The inital rolloff matches and 18 db slope but the ultimate slope is a wee bit softer)

The idea being that if the inital slopes are known it makes the power response and summing on axis more predictable. Sharper slopes tend to be better at these frequencies where the cone transducer is crossing over the a horn or a wave guide that may be not aligned with the woofer.

[Wonderboy]

Ok "Time Lord":), so all I need with for my low pass on the 2012 is 1.38Mh and a 49uF?

Kevin

P.S. Is that you selling the wooden TAD horns on ebay?

[Ian Mackenzie]

I hope you are not making fun of me?

I take my job very seriously.:D

To answer your question no. Selling tad horn my ass.

[Ian Mackenzie]

Ok "Time Lord":), so all I need with for my low pass on the 2012 is 1.38Mh and a 49uF?

Kevin




What did I say earlier??

http://www.audioheritage.org/vbulletin/showpost.php?p=229353&postcount=27

I hope your not a Zilch Clone.

[Wonderboy]

I would never make fun of a "Time Lord" :applaud:, I know what's good for me! (I have a big smile on my face, just try'n to get ya going, haha!) I do respect you, anyone who can eat pasta and figure this stuff out at the same time, I RESPECT! (just don't let it go to your head:)).

I never figured out how to use the "quote" thing, but never tried yet. But I must apologize I was scanning through the posts and guess I missed that one you quoted, that one you said earlier about needing actual driver data etc and focused on the measurement graph one.

What's wrong with selling TAD horns, they look nice and the price is right?

Don't pick on Zilch, he's been good to me, I think:blink:, little short bursts of info, but good info.

After seeing those TAD horns for sale and your offer on the TAD drivers (after having a couple beers) I was very tempted to go for it, thought about selling my wedding ring, which might not have been such a bad idea but I don't think I would live long enough to enjoy the music:bash:.

Kev.

[Ian Mackenzie]

I think selling the ring could be a bad omen!!

No problems

You could try those values just for grins but it is not like a piece meal thing.

You need to properly mount and load the driver on a baffle and do some realistic measurements.

I was tempted to buy a pair but they are very pricey.

I dont know what end of Canada you are in but yo might want to talk to Earl or meet up with a local group of dudes who can steer you the right passage.

The thing is the 2012H is a world class driver and nothing less than perfect would be right.

[Baron030]

There are other considerations such as what baffle is the driver on and what is the voice coil x, y, z orientation as well as the mic distance and drive voltage but that's out of scope in this particular instance.

Thinking about I think, I have tested this driver hundreds of times proto typing various EQ circuits. Well, here are the latest and greatest test results that I have been able to come up with on the 2012H driver. Since, some people prefer closed boxes over bass-reflex enclosure for their mid-bass/mid-range drivers. I decided to run two complete sets of tests. So, one set was done with my ports plugged. In any case, the enclosure has a net internal volume of 0.5 cu ft. The front of my enclosure is 26.5” wide and 46.5” high. And the distances between the center of the 2012 driver and each edge are as follows 24.5”, 22.0”, 14.75” and 11.75”. So, I hope that covers all the baffle details. The mic distance was 1 meter from the 2012H driver and it was placed at the same height as the driver. Since, the center of the voice coil is only 24.5 inches above the floor a layer of R11 fiberglass was placed on the floor to reduce its reflection. And the next closest reflecting surface is a concrete ceiling, and it is just 10.56 milliseconds away. For charting purposes, I used the MLS processing tools and db shifted the all of the outputs to 0.00 dBV @ 1,000Hz. And other then gating to remove room reflections, no other processing was done.
By normalizing the data this why, it is then possible to make comparisons between each of the charts. The first chart shows the closed box and ported enclosure impedances of my right driver. The second chart shows the response of two drivers when each is mounted in a closed box. And the third charts, shows the drivers when each is mounted in a bass reflex enclosure. The forth chart shows how a 1.5mH coil can be used to flatten the response. And the final chart shows what my 0.3mH, 82.01uF, 10ohm, LRC EQ circuit can do.

And for anyone that is interested, I will be happy to post the CLIO MLS and SINI files or I can even export the data and post it as ANSII text files.

Baron030:)

[johnaec]

It's almost gotten to the point of complication that I'm almost thinking I should just sell these NIB 2012H and other drivers and start working towards some pre-built ___________________funds... Realistically, a pair of PS1400's to go with my PT800's would probably keep me happy right now.

Unfortunately, much as I've wanted to work towards some kind of dream system, I'm dealing with some medical issues right now where it's getting too hard for me to try reaching any of the even lower goals much of the time. Hopefully, things may change... In the meantime, I'm still watching, but may not have as much active input as I'd like.

John

[Baron030]

Well, I tried something new today.
Other than uploading some Jpeg photos, I have never tried uploading data files before.
The attachment is pretty much self explanatory.
Unfortunately, the CLIO files appear to be too large to post, even when zipped.:help:

Baron030:)

[Ian Mackenzie]

Baron Von Clio Nicemeister,

Can you take a pic and attach of the baffle and measurement set -up please.

Ian;)

[Baron030]

Hi Ian

Doh! :banghead:
Somehow, I just knew that I should have pulled out a camera and taken a few pictures while running these tests. And I just got through putting everything back in its place. Every time I do these tests, it like ripping up my living room. Well, I try to follow all of the procedures in Joseph D’Appolito’s book on testing loudspeakers. So, the enclosures are pulled towards the center of the room away from all of the walls. The biggest challenge is the slap echo off of the ceiling. There is nothing I can do other then limit the time domain of the measurement, which in this case was started at 2.90ms and stopped at 7.50ms before the slap echo could arrive. I wish the weather was not so cold. Otherwise, I would have done these measurements outdoors, terrorizing my entire apartment complex 120db MLS impulses. And I am just kidding about running tests at 120db.

The drivers were tested in the DIY enclosure pictured in my Avatar. And I simply measured all of the distances between the center of the 2012H driver and the edges of the enclosure, which I assumed would describe the baffle adequately.

Is there something that looks really wrong or very odd with my results? In a way, I am still learning the fine points of this software package. So, I would appreciate your input.

Baron030:)

[Ian Mackenzie]

Hi Ian

Doh! :banghead:
Somehow, I just knew that I should have pulled out a camera and taken a few pictures while running these tests. And I just got through putting everything back in its place. Every time I do these tests, it like ripping up my living room. Well, I try to follow all of the procedures in Joseph D’Appolito’s book on testing loudspeakers. So, the enclosures are pulled towards the center of the room away from all of the walls. The biggest challenge is the slap echo off of the ceiling. There is nothing I can do other then limit the time domain of the measurement, which in this case was started at 2.90ms and stopped at 7.50ms before the slap echo could arrive. I wish the weather was not so cold. Otherwise, I would have done these measurements outdoors, terrorizing my entire apartment complex 120db MLS impulses. And I am just kidding about running tests at 120db.

The drivers were tested in the DIY enclosure pictured in my Avatar. And I simply measured all of the distances between the center of the 2012H driver and the edges of the enclosure, which I assumed would describe the baffle adequately.

Is there something that looks really wrong or very odd with my results? In a way, I am still learning the fine points of this software package. So, I would appreciate your input.

Baron030:)

Hey,

I have the same problem doing tests, my favourite is the sweep.

Sorrry I did not twig it was your avatar.

Cool system

Nothing wrong but the peak at 1 k hertz is off.

I saw from measurements of another tightly packed baffle recently and the proximity of the ports made quite a different. Nothing you can do about that as its all about what happens on your baffle. The horn immediately above could also have an effect. They are really touchy frequencies.

You have probably aleady tried this but I would try just covering the ports and trial more fibre glass inside.

http://www.trueaudio.com/st_diff1.htm
http://www.frazierspeakers.com/download/bounds.pdf

http://www.pvconsultants.com/audio/diffraction/downloadbds.htm

[Wonderboy]

Interesting stuff guys, Baron and Ian, I have been doing some reading on crossovers and think I might go back to the active crossover, seems to have WAY less complications, not sure if I can swing it or not but it might be worth a try.

To bad that Johneac sounds like he is losing interest, I know how you feel John, it sounds pretty complicated but don't give up on your dream system, you might never forgive yourself. It's not as complicated as it sounds, even if you don't do it perfect, I don't think people will notice or measure it.

Thanks again for all your advice guys it is much appreciated. Just for the record, I was not making fun of you Ian, I kid around a lot, maybe to much at times, I was laughing with you, not at you.... Ahhh, now that I got that off my chest, I'll go back to my reading, catch ya's later!

Kevin:)

[Ian Mackenzie]

Me, I was only Yankin (get it) your chain.

I take time out to play with this stuff between brain farts!

When I get a mini I was screw with Sound Easy and see what it says when you have a baffle like yours.

Ian

[johnaec]

To bad that Johneac sounds like he is losing interest, I know how you feel John, it sounds pretty complicated but don't give up on your dream system, you might never forgive yourself. It's not as complicated as it sounds, even if you don't do it perfect, I don't think people will notice or measure it.It's not that I've lost interest - I actually have every driver, crossover, EQs, amps, and most of the cabinet material right here at hand for the complete system. Frankly, it's about the most interesting thing to me right now! Withough going into detail, the problem is that I'm dealing with some very serious medical issues right now, and sometimes it's hard to even function. Sometimes, I feel like the interaction I see on this forum is one of the things still helping me get by. So please don't let my input influence any enthusiam - I'm dealing with things the best that I can, but sometimes my health just gets in the way...hopefully, the Lord willing, that may change...

John

[grumpy]

Hi John, Hope your health takes a turn for the better. You've got this motley
crew behind you :D

[Baron030]

Hi Ian

I now understand what you are saying about baffles. They can have some pretty dramatic changes to the response. And I don’t mean to argue, but there one thing that I am certain about. There is a something strange going on between 800Hz and 1 KHz with this driver. And it even appears on the JBL 2012H driver’s spec sheet. Admittedly, every measurement that I have ever made does show this anomaly to be larger then JBL’s published response by a few DB. So, maybe you are right about my baffle is making that peak worse. Now, I have tried plugging the ports and the results are posted here. Other then an a few db increase in the roll off below 350 Hz, I don’t see much difference with plugging the ports.

Before starting my 15” 4-way project, I really debated a long time between “closed vs. ported” and even between “Dog Box vs. Sonotube”. Well, right or wrong I did go with a ported rectangular dog box, with an angled back panel, and a heavy fill. For a box this small, 1” to 2” of fiber glass is about the most that can be packed in without covering the ports and a small vent hole on the back of the driver. So, I guess that constitutes a heavy fill. And I don’t think adding more fiber glass fill to the doggy box is going to change much.

During, this debate I ran tests using smaller test boxes, with no baffle at all, other then the box itself. Now, this was a time when I did not have CLIO. So, the response curves were not as accurate as they are now. But, in all cases there still was a peak at about 1 kHz. And it was very objectionable during listen tests, which necessitated adding a passive EQ circuit to an otherwise all active system.

The only real point that I am trying to make here is that the 1 KHz. peak is not an error in my testing and I don’t think it is a baffle related anomaly.

Now, my first attempt at an EQ circuit was a 1.5mH coil in series with the driver. Surprisingly, it did work well enough to prevent me from selling the 2012 drivers for a big loss. But, it did not mate well with my 2382/2446h driver. There was a dip between 1 KHz and 1.2 KHz and I would think that other HF horns with a deeper low end then the 2382 would not have this problem. So, you are probably in the ball park with a 1.38Mh and a 49uF crossover. Maybe, not at home plate yet, but definitely in the ball park.

Johnaec, I am sad to here about the medical issues, I hope you get better soon.

Baron030:)

[Doc Mark]

That combination of drivers looks OK, but you may have problems getting passive crossovers lined up easily. What I'd do is use a passive only for the VHF 2405, around 7K or 8K, and use an active 3-way crossover for the rest, each range with its own amp. Of course, you'll need some sort of EQ with that, looking at the different response characteristics of the different drivers. But I think you could get it sounding fairly good, and capable of prodigious, (sp?), output if desired.

John

Hello, John,

I hope you're feeling better, and that your medical misadventure is on the way to being history, instead of current news. In any case, I was perusing this thread, and realized that when I thanked Baron030 for his suggestion of using a passive crossover for my 2405's, and active for everything else, you had already suggested that exact same thing, and I completely forgot to thank you, too, Sir!! Please accept my humble apology, and also my thanks for that outstanding idea!! It is a simple, but absolutely perfect solution to my quandry about making an actual 5-way system, including a subwoofer, and I very much appreciate your having suggested it!!!

Also, please don't give up on creating your dream system, John!! As one who gathered JBL components, then carried them around, and stored them in various homes in which we lived, for more than 20 years, I know that it sometimes takes quite a while for things to come together! But, I have every condidence that for you, just as it happened for me, time will eventually present itself, and your health will improve, and then you can finally realize your long-awaited dream system!! It will have been well worth the wait, my Friend!! Hang in there, and please keep us posted as to your progress in getting better. Take care, and God Bless!

Every Good Wish,
Doc

[Ian Mackenzie]

Thanks,

Well its definately not diy user friendly if this is typical of production samples.

Some peaks are okay and some arn't as in of they are well damped and narrow.

If you can hear this one and is does not show on the impediance curve its weird.

The JBL data sheets are probably smoothed and I note your response curves are un smoothed but what the heck its there.

[Baron030]

Hi Ian

Yes, I would have to agree with you about the 2012H as not being very user friendly. :banghead::banghead::banghead:
But, the 1 KHz peak does respond well to notch filtering. And if people can accept using this driver over a relatively narrow range of say about 400 Hz to 1200 Hz then my LCR solution for active crossover networks does work fairly well. Pictured below is the exact same data that I posted earlier. But, now it has 1/3 octave smoothing and I “db shifted" the left and right drivers outputs a little bit. So, that they are now normalized at 800Hz instead of the 1 KHz like I had posted earlier. Other then smoothing and db shifting, no other processing was done. With my 24db/octave electronic crossover set at 400Hz and 1200 Hz, you can see how I have gotten this driver to perform well in my system.

Now, the real challenge is to find a passive solution for someone like Kevin who wants to use an electronic crossover to handle the lower crossover point and then have a passive crossover network handle the upper crossover point.

Well, maybe I am stubborn or just plan stupid. But, I still think that a 1 KHz series notch filter combined 2nd or 3rd order low pass filter could be a solution to Kevin's problems. And of the two different orders, I like your idea of using a 2nd order as an 18db/octive low pass filter. From my experiments with parallel LCR filters, I remember that I was always playing the 1 KHz peak against a LCR filter induced dip at 800 Hz and the higher the LCR "Q" the better the results that I got. And I would think that without a series notch filter, a 2nd order low pass network would have fairly flat response over a 400 Hz to 1000 Hz range, but not without a big dip at 800Hz. or it could have a really flat between 400 and 800Hz and still have a 1 KHz peak. Of the two flavors of 2nd order filter that I just described, the one with the 1 KHz peak would be the easier to fix with a series notch filter. But, I am not sure how the overall system impedance would be affected. It could really mess things up with the high pass section of the crossover or then again maybe not? :dont-know

There is one thing that I can say for certain. If someone can get past this hurtle, then I think there will be a lot more successful DIY projects out there using the 2012H driver.

Baron030:)

[4313B]

Aren't 2122H's and 2123H's alot cheaper?

[Robh3606]

Well here's a 2122 in a 4344 baffle enclosure.

[Ian Mackenzie]

Like the scale Rob,

I wonder what its is like where you sit!