Pondering an IDS-25 Clone (sort of) for HT

[fjhuerta]

Whatever measurements I had of the array will have to suffice. I'll now follow this thread closely.

I sold my speakers A friend of my dad listened to them - he had a BeoLab 5500 system and wanted to upgrade. He bought my array!

So I'll probably build something else - better - later during the year. I can't wait to read about driver tests.

[JonMarsh]

I can't wait to read about driver tests.

Me neither! But getting ready for this trip has consumed all the spare CPU cycles and then some!

Congratulations on selling your arrays! You're now officially in the Line Array business, and a successful vendor! :W

Seriously, I have numerous samples of all the major driver types I think I need to investigate at the moment, so I should be set for doing that pretty soon after I get back- though there are a few other things on the plate already, including a medical procedure, that will divert my attention at least temporarily. Still, I'm looking forward to it- thinking in terms of a combination of the LA-25 project and the corner arrays, executed in LBL bamboo, with phenolic baffles to minimize rear side driver masking. We'll see... many a slip twixt the cup and the lip, and all...

[---k---]

Whatever measurements I had of the array will have to suffice. I'll now follow this thread closely.

I sold my speakers A friend of my dad listened to them - he had a BeoLab 5500 system and wanted to upgrade. He bought my array!

So I'll probably build something else - better - later during the year. I can't wait to read about driver tests.

Wow. That's a testimony! Did you get to sell at a profit over material costs? Enough to afford even fancier drivers?

I have to admit, this has me intrigued. Later this year, I get to build a new man cave. I waffle back and forth from reusing my Khans because I have so much invested in them to a line array to a big waveguide setup.

[fjhuerta]

Wow. That's a testimony! Did you get to sell at a profit over material costs? Enough to afford even fancier drivers?

I have to admit, this has me intrigued. Later this year, I get to build a new man cave. I waffle back and forth from reusing my Khans because I have so much invested in them to a line array to a big waveguide setup.

Thanks for your kind words, John, K!

I sold them and made a nice 60% profit. I'll use the money to do some house repair work... although my dad's friend also loved my OB speakers, so if he gets them for his beach house (which, if I'm able to sell them, I'll have to visit in order to install them ) I'll definitely get some spare money for new toys!

I'm currently using a 2xDayton RS275, 2xW41337s, 1xSB29 in a 200L enclosure in my main system. When compared to the line array, the "monkey coffin" speakers have far more visceral impact and pinpoint imaging. I prefer them for rock. Any other thing - the line arrays sounded far better. When listening to jazz or classical music the difference was staggering - the monkey coffins sounded completely wrong, and the arrays were like a live performance. You were completely enveloped in sound - I guess that's the main difference between listening nearfield vs. farfield. Conversely, rock music sounded a bit bland and artificial with the arrays, while the coffins were exciting.

The line arrays, were far closer to the real thing than anything else I've ever built. That's for sure. They never failed to impress anyone who listened to them.

[---k---]

Great comments. Makes me think the line arrays wouldn't be the best for movies then where I'd want the visceral impact and pinpoint imaging. But then again, so much of what makes movies is the ambient background soundtrack that you want to envelope you....

Do you wonder how much the differences is the crossover and EQ? I've heard little 2-ways that sound pretty big, open and air. I've also heard some that sound like small boxes. Everyone uses "forward" and "laid back" to describe speakers, which is just the crossover decisions. Shoot, just moving my speakers out into the the room a little can make the sound open up or collapse - depending on how close they are to the walls and TV. Do you think if you'd spend more time with the EQ you could make them go either way?

[fjhuerta]

Great comments. Makes me think the line arrays wouldn't be the best for movies then where I'd want the visceral impact and pinpoint imaging. But then again, so much of what makes movies is the ambient background soundtrack that you want to envelope you....

Do you wonder how much the differences is the crossover and EQ? I've heard little 2-ways that sound pretty big, open and air. I've also heard some that sound like small boxes. Everyone uses "forward" and "laid back" to describe speakers, which is just the crossover decisions. Shoot, just moving my speakers out into the the room a little can make the sound open up or collapse - depending on how close they are to the walls and TV. Do you think if you'd spend more time with the EQ you could make them go either way?

I suppose I could raise the bass level a bit by moving them towards a corner (something I couldn't do, the speakers are too tall!). But I don't know if you could get the "punch" of a traditional speaker. For the lack of a better explanation, I believe creating such a large virtual array means that even though you are actually listening to very high SPL's the soundfield is far bigger - not a point source. Perhaps the "impact" comes from actually having a single driver moving massive amounts of air in a very specific point in space? Because even though I was listening to music at pretty much stupid levels, I could never feel it. As a matter of fact, it was sort of difficult to understand how loud music was until you tried to speak - then you realized you couldn't hear anyone.

Same thing happened to treble. It's not exactly delicate and definitely not localized in space. It was airy, and all over the place. It didn't sound precise or "exact", but it sounded very lifelike. These speakers made me understand music is not created on a single point in space, but that we actually like dispersion more than absorption.

One other thing. I installed the speakers at my dad's friend home last week-end. He put them in the worst place possible - in the middle of a room, facing his stairs, and is doing the listening off-axis. The place is like 10 meters tall. The speakers look like dwarves. And even in that horrible position, they manage to sound decent.

[---k---]

It sounds like something that just has to be experienced. Thanks again for you comments.

[Olympic]

My IDS clones using the Vifa TG9FD10-08 drivers. They sound phenomenal.

Image not available

[---k---]

Very nice. Can you tell us about any EQ you're using with them

[Olympic]

Pondering an IDS-25 Clone (sort of) for HT

I am using a McIntosh MQ-107 for equalization. I built these last year based on Roger's Audio Express article from several years ago.

[fjhuerta]

I've listened to my arrays on my friend's home twice now.

Associated hardware: Behringer UltraCurve, Yamaha RX-V992 amp, Pioneer DVD player.

I'm still amazed at their imaging. One of the things these speakers can do that no other can is stereo imaging. Even though I'm listening off axis there's still a bit of stereo sound.

They are in a less than stellar position. When I'm near a wall, sometimes it seems that sounds are coming from the wall itself, not the speaker.

They are extremely efficient.

They do this trick that, when you think you are listening at very low levels.. then try to talk and you realize you can't hear one another. You just don't know the real listening levels until you have a point of reference.

There's a thing, though... I boosted treble and bass using the UltraCurve, and there's quite a bit of ZZZing to the treble. I could never determine if its the amp being overloaded or the UltraCurve making nasty sounds. I checked that the Behringer wasn't digitally clipping - the ZZZing is still there. This never happened with the MiniDSP unit.

[---k---]

Javi,
I really enjoy reading about these, since I've never heard a line array. It really makes me want to go build one. Cost and where the heck am I going to put another pair of speakers is holding me back. So, please keep posting.

[JonMarsh]

I've listened to my arrays on my friend's home twice now.

Associated hardware: Behringer UltraCurve, Yamaha RX-V992 amp, Pioneer DVD player.

I'm still amazed at their imaging. One of the things these speakers can do that no other can is stereo imaging. Even though I'm listening off axis there's still a bit of stereo sound.

They are in a less than stellar position. When I'm near a wall, sometimes it seems that sounds are coming from the wall itself, not the speaker.

They are extremely efficient.

They do this trick that, when you think you are listening at very low levels.. then try to talk and you realize you can't hear one another. You just don't know the real listening levels until you have a point of reference.

There's a thing, though... I boosted treble and bass using the UltraCurve, and there's quite a bit of ZZZing to the treble. I could never determine if its the amp being overloaded or the UltraCurve making nasty sounds. I checked that the Behringer wasn't digitally clipping - the ZZZing is still there. This never happened with the MiniDSP unit.

Sounds like classic digititus with the Behringer. That's an endorsement for the mini-DSP- I haven't ever heard mine, and have been reluctant to consider it for a higher end application.

[JonMarsh]

My IDS clones using the Vifa TG9FD10-08 drivers. They sound phenomenal.

Image not available

Thanks for sharing your experience- looks like you did a very nice job on the build! :T

[Wesayso]

Fun to see pictures of my own speaker build on another site. I thought why not join the discussion.
After the cracks in my translam build I have been able to get them up and running. This is what they look like right now:




Why did I choose the TC9? It has a great deal in common with the TG9 version (the 8 Ohm one) but had a few things I was looking for.
First there is slightly more rise in it's higher frequencies, not a bad thing for line arrays where due to comb filtering you are expecting a drop in HF output.
Second, all distortion graphs I found indicated it is well up for the job. Graphs showing distortion at 96 dB @ 1 meter still looked good.
Having had aramid mids in the past and moving to paper cones (in another system) I knew I liked paper as a cone material. On paper I'll admit the TG9FD10-08 is slightly better.
But I was a bit concerned about the cone material (just a hunch) and figured the paper cones would give me a more natural sound. The amount of money saved was welcome too .
Here's a distortion graph at the listening position 3 meters from the arrays. Taken on a normal day meaning a lot of ambient noise in that graph as well.



I live along a very busy street and hear the cars passing while taking these measurements (well, not during, you get the point)
As EQ I use a PC based system with JRiver as convolver and the free DRC tool to equalize the lines.
Since the above graph I've added some damping panels to my room, greatly improving the results.
As you can see my lines are quite close to the walls, one of them in an actual corner. Behind that curtain there's a huge damping panel, 3" thick.
The corner/close to wall placement is how the arrays are capable of very low bass. I've actually since then moved the roll of a bit higher. I'm now at 37 Hz as -3 dB and 25 Hz -10dB.
That gives me less worries if/when I want to blast it loud.

I'd recommend looking into FIR based filtering for arrays like this. Be it the free DRC, Audiolense or Acourate... I've done the PEQ based filtering but FIR based just gives so much more in return. If you do decide to run regular equalizers be sure to gate the higher frequency measurements to base the EQ upon.
My behringer DEQ 24/96 sits in a box upstairs, unused since my project start in 2011.

[kevinm]

Man those things are so cool looking. Excellent look! Well done!

[augerpro]

Really nice lines! The center speaker is a bit...incongruous though

[oneplustwo]

Jon - any news on the driver testing for this project? Or are you still digging out from the ancient ice of antarctica?

[JonMarsh]

Good question! I'm digging out from the ancient ice, and from my daughter's Bridal shower (you know who being the official photographer), and this last week a lot of things went sort of sideways at work, what with a lot of people being out for spring break, and some issues coming up, including an engineer we hired a year ago who's been deeply involved in a critical program taking one day off to close on his new house, and the next day giving notice, because the previous night he'd accepted an offer with a company that is local to the US and has a full blown local engineering organization, which he believes (rightly so, I think) will be more advantageous to his career growth. (plus, he was being setup to be the point guy for that big customer in Cupertino for a new project, and he didn't really like that, given what the work load usually becomes- he was with us in the lab in Cupertino the last year. I had to handle the separation duties and data collection, because our mutual boss was out on medical issues that day. So, Saturday I wrote a longish email to our mutual manager using the parable of putting the frog in a pot with cold water and putting it on the stove and seeing how long or if the frog ever realizes the water is getting too hot before he jumps out... explaining he shouldn't really have been surprised, given that this guy comes from product design companies, not semiconductor companies, and pointing out that this frog (me) has been in the water on the stove nearly 30 years, and has developed coping mechanisms, but they're not ones most employees would willingly embrace (buying my own computing hardware and software for work to get around ups and downs in finance and budget restrictions; paying for materials for time critical projects out of my own pocket, because our procurement process has become so regulatory and lengthy; buying some of my own tools and test equipment, because of budget binds at work; doing technical work myself because the technical assigned to support the project was incompetent at what he was required to do (assemble PCB's and solder via IR reflow in a small system- I've never seen new assembled G10 PCBs that were charred on parts of the G10 laminate- BTW, he's still here and in that lab. He's a nice guy and all, ex Navy, just not very good at some important things... and not properly supervised or trained. I.E., he reports in to a marketing manager. sheesh.... how Dilbert can you get...

This week we've also been discussing equipment for the lab, having to push our director to authorize repair of a scope, when it's one of only two functioning test stations. And only low power stations; don't get me going about what happened to my bench while I was out on assignment- stripped, basically.

That's a topic for a meeting on Wednesday... should be interesting. :W

Numero Uno priority at the moment (today) is GF's sub cabinet- out sanding the expoxy coat today, getting ready for veneering with Cherry. I've had all the pieces around to do that for a year, but no time.

And our last project team meeting was attended by our VP, regarding topics with that big customer, and I'd previously been invited to make a small presentation about the trip, and VP saw it, and now I'm presenting a bigger presentation for a lunch and learn for our whole location, in early May. Gotta get more files "developed" and put that together...

It's just a typical logistics exercise, like this:



So, I want to get back to this soon, but I've got to also finish moving the Isiris back to the Livermore R&D facility and get them polished up, and crossovers internal, and I feel I should finish the follow up on Wavecor Ardent and the Esoteric + 9700 stuff first.

Gonna be a busy spring- I ordered a BTO configuration of the new Macbook- what we were working on was related to that, and sheesh, I must have picked just the right configuration, because it won't be available until mid May. This is going to be a Spring of delayed gratification! :W


(well, not in all things- I did buy that NAD M22 nCore based amp, it's working in the system this afternoon, sounds quite nice, very clean and neutral, and of course, now that temps have warmed up and it doesn't drop to 50 or less overnight in the family room, the M52 seems to be working flawlessly- maybe I'll just update it from the replacement raid drive, on which I fixed all the album art issues and some other tweaks).

[flamethrower1]

I purchased the Fountek 83's with just this kind of build in mind, looks like I am going to have to buy some more wood clamps

[oneplustwo]

Keep us updated! I'm still waiting to decide on what driver since I have time as I wait for my house reno. But definitely thinking about trying some permutation.

[JonMarsh]

I'll do that.. this weekend, though, it's two 5K events, one a charity event sponsored by a local Girl Scout troop for Parkinson's awareness and research, the other is the annual Devil Mountain run. At least the General Finishes stuff came in for the sub cabinet.

Don't worry- I have the drivers to evaluate for this stacked up in some nice slim clear "Really Right Stuff" bins, staring me in the face every time I come into the home office.

[fjhuerta]

I purchased the Fountek 83's with just this kind of build in mind, looks like I am going to have to buy some more wood clamps

What kind of EQ are you thinking about using?

[flamethrower1]

I was planning on doing the mini dsp as you did.
I do have a question though.
I purchased an XMC1 and the full version of Dirac, do you think that the room correction filters will play together well with the mini dsp?
Also, did you ever post any wiring, cabinet dimensions or other items on another thread over at the Parts Express forum?

[flamethrower1]

Jon, just wondering how the measurements are going?
Sorry to jack your thread.
I saw the Founteks on PE and then stumbled on fjhuerta's thread on PE and decided to do his build.
Along time ago I had a chance to hear some line arrays that were similar and really liked the way they sounded.
After examining Rogers original design. I am second guessing myself.
Anyway, hope all is good and wait for your results, Thanks

[flamethrower1]

After doing some initial design layouts with the Founteks, I found that I can not keep the dimensions under 8 feet with 25 drivers.
I know, bad planning on my part.
Will probably have to use A few less drivers, I saw on the original site that this would not have to much of an affect.
Anyways, wish I would have stumbled on this thread before pulling the trigger.
I am going to go ahead and build with what I have and give them to a friend of mine.

[JonMarsh]

Must be a good friend! :T

[flamethrower1]

Jon, did you get a chance to do any testing on the drvers?

[flamethrower1]

I was going through some final dimensional checks and found a discrepancy on the original website, these are going to be cut and paste.
The IDS-25 has a footprint for the base that is only 14" wide and 12" deep. The column itself is only 7" wide (tapering to 6" in front) and 9-1/4" deep. Because the system is capable of significant output down to 20 Hz, no subwoofer is needed.
System dimensions:



Including standard base

88-3/4" high, 14" wide and 12" deep.

Without base

87-1/4" high, 7-1/2" wide (tapering to 5-1/2" in front) and 9-1/4" deep

Can anyone who has built these tell me which one is correct.
I am going to build a down and dirty build with the Founteks so my cabinet height is going to be a couple of inches taller than what can be done with the Vifas.
Going to do another pair though with the originals for my house with a couple of less drivers due to height constraints.
Sorry for being a APITA and crashing a thread, but I am not on the same level technically as some of you guys.
I am a person who is better at woodworking and can follow an electrical schematic
Any input and/or help would be appreciated
Thanks. Greg

[Wesayso]

7-1/2" x 5-1/2" is the right one if you're talking about the IDS-25 outer enclosure dimensions.
The Founteks are a different driver though, might prefer a different volume for maximum performance.

[flamethrower1]

7-1/2" x 5-1/2" is the right one if you're talking about the IDS-25 outer enclosure dimensions.
The Founteks are a different driver though, might prefer a different volume for maximum performance.

Hey, thanks for getting back to me that quick, it is appreciated.
I found your build and read the whole thing, those are some very impressive speakers, great craftsmanship.

[JonMarsh]

Jon, did you get a chance to do any testing on the drvers?

Not yet... I have a terrifyingly deep To-Do list these days... still finishing GF's HT sub. That should be done and dialed in this weekend. I have those parts boxed and stacked in my man cave, waiting for their turn...

[flamethrower1]

Yeah, I know how the To-do list thing goes.
I decided to plumb my dust collector so I could have drop outs and blast gates for each tool in my shop before I started doing any cutting.
As I said before, I am going to run with the drivers I have now on this build and see how things go.
If I like the way the sound, I build another set minus a couple of drivers for my house.

Thanks, Greg

[JonMarsh]

Yeah, I know how the To-do list thing goes.
I decided to plumb my dust collector so I could have drop outs and blast gates for each tool in my shop before I started doing any cutting.
As I said before, I am going to run with the drivers I have now on this build and see how things go.
If I like the way the sound, I build another set minus a couple of drivers for my house.

Thanks, Greg

Pretty reasonable plan, Greg- let us know how it works out.

[flamethrower1]

Does any body have a wiring schematic for the original IDS-25, or something that is close?
I know that they were sires/parallel in sets of 5.
Just wondering how he burned up 70 ft of wire in a cabinet ?

Oh, just wondering if anyone came across this build, the guy did some nice work on these.
http://www.faktiskt.se/phpBB3/viewtopic.php?t=55019.
You will have to translate it though

Thanks,Greg

[SATX]

Any idea why PE lists power handling for the TC9FD at 30W and the TG9FD at 5W? The voice coil is the same size for both, but there's no information about the materials used.

[JonMarsh]

Thanks for the link to that build, language differences aside. It wouldn't be a trivial project to run all this through Google Translate, but it might be worth the effort...

Wiring would be done by connecting 5 drivers in series connection, creating 5 sets of series connection; these are then wired in parallel. When one has so many drivers, there are acoustic considerations about having them all in the same chamber (NOT GOOD!) because if one driver is a little weaker on BL product, it can be over powered by the back pressure- at least, this has been reported in some cases. Best thing from others experience seems to be to isolate drivers in sets of 5 that are wired in series, then wire in parallel the drivers in each sub chamber.

How much wire you use will undoubtedly depend on how you want to arrange the wiring- if a central termination block is used in the speaker, even just for the parallel set connections, the wire can really add up. I'd recommend drawing it out in a schematic, in a CAD tool or on paper, before the build.

[JonMarsh]

This picture from that build should give an idea of why you can wind up using a lot of wire in one of these, if you try to do it "neatly" with organized termination:

[flamethrower1]

Thanks for the tip on isolating the drivers, that what I was first considering doing.
Then I saw other builds that did not do this and on Rogers website he said that they built the cabinets with bracing every two drivers so I thought that they were not isolated.
Again on the wiring, why cant you make a harness (2 wires) coming from the speaker posts and have a pos and neg drop out at each group of five which would be wired in series.

[JonMarsh]

You probably could... depends on how you want to terminate it. With those little terminals, you don't want to be soldering multiple leads.. try drawing it out in detail, including the terminal block hardware.

[JonMarsh]

Well, been thinking about this again, best not to take action precipitously, of course...

Actually, I was awake in the wee hours this morning, because of the current and upcoming work project, and being in a position where I needed to herd cats (get other AE's to work on some aspects of it, per my bosses desire to mentor and involved them) (but of course, their immediate bosses have other plans... )

And it occurred to me if I was going to be awake I should be thinking about speaker projects... and one thing I remembered was buying a couple of RS100's back when they first case out, as a possible low cost midrange for a "budget" version of the original Ardent design. I never did get around to measuring them, but I still have them, figure I should do that, as my recollection was that they were fairly wide range.

So this AM, while at Starbucks, I did some due diligence, because I also had this faint recollection that there might be a truncated frame version- something that looks like this:




8 Ohms, not bad looking, and a "genuine" 4mm Xmax, according to Dayton Audio. The rear "window" is about 25mm tall, better than a lot of the small drivers, but still suggesting a phenolic baffle is very desirable.

Frequency response? Fs is about 90 Hz, with a QTS in a nice range...






I'd better think about breaking out the set I have and making a test panel for one of them, too.


I think all would have been well at that point, if I'd just been able to turn over and go back to sleep, but then the notion of what to do about my next project at work came up... an SMPS supply for Class D amplifiers... to be ready by CES in January... now, would a live demonstration be desirable? What speakers?


Hmmm, you know, we could probably still get a very nice low end with an SW223BD02 and an Wavecor PR in a 1 cu ft enclosure- (say, PE MTM) and then, what if we make it like a wide band NeoD CC, with the Dayton RS52AN dome midrange, and that SB small form factor tweeter I've been threatening to do something with? Wouldn't be terribly efficient, and would be a bit power hungry, with that 4 ohm woofer - but I'm going to have to look at it closely and model the combination. Would use an Ardent/Isiris derived crossover, not the Duelund, as it will work better with the actual driver offsets. Man, they would be heavy, though... and it would be pretty tight putting an 8-3/4" driver on a 9" wide baffle. Definitely need a custom LBL one.

But the bottom end should be very extended and powerful for that size box.... and they would make a nice set of mix monitors for my music playing/recording stuff...

See what haunts me at night? Be glad you're not me... be very glad! :W

[flamethrower1]

Jon, when you talk about a phenolic baffle, what thickness would you use?
I did some checking locally and that stuff is expensive.
I was doing some mock baffles for the Founteks this weekend to see what I needed to do to provide some breathing room for them.
Ended up flush mounting the drivers and routing out the back of the speaker cut out with a 15 degree chamfer bit, tried a 45 at first and it left hardly any material for the mounting screws.
Also, would like to have one more window brace in the center of each 5 speaker compartment but that would mean it would be directly behind one of the speakers.
Could I do this using an "H" shaped brace (like the pics attached) without causing audible problems?
Anyway, if you could let me know what you think, I would appreciate it

[BobEllis]

How about a 45° chamfer between the mounting screws? Four sections of larger chamfer would open it up quite a bit.

[JonMarsh]

I'd expect to be using something like 3/4" thick material, with a 1/2 depth 45 degree bevel. There are a lot of different phenolics out there, and yes, they are expensive... there are good reasons why Wilson Audio and Lockport speakers are as expensive as they are. But rear window issues are pretty important factors on frequency response, even for larger drivers like the 5" Seas Excel. When you get down to 4" or 3", it's even more critical.

What I plan to do is to use a strip style front baffle, for which I'll do all the cutting, drilling, and machining prior to assembling the cabinet, and they will likely be a series of smaller segments mounted in the front, with similar material as baffle supports/braces.

I buy CE grade and G10 in 3/8" or 1/2" on eBay, typically 12" x 24" or 24" by 24". Mostly I use CE grade, which is designed for high strength high electrical insulation in high voltage switch gear, it's a good combination of strength and machinability compared with G10, which is even stronger because it incorporates glass fiber, but harder to work with.

I'll be using this also in setting up a test enclosure for driver testing shortly... in this case, I may just cut out holes and use a bit of silicone seal to mount the drivers for testing, then pop them off or remove the whole baffle plate.

[flamethrower1]

I will try the 45 as you propose, any thoughts on the brace ?

Thanks, Greg