"Crossover Design for New Project"

OK I think I could use some help on designing a Crossover from scratch that I need to complete project I would like to undertake.I have all the components and was talking with a friend "dgwojo" that I may need modeling software for the efficiency mismatches.Any and all suggestions or help would be most welcomed.OK the only components missing now are the Crossovers.I would like to use dual 416-8B's for LF and a 511E/288C with a 288-8G diaghram 23763 8 ohm for MF & HF and for UHF EV T350's all drivers are 8 ohm.

Now I talked to the Zilchster and he recommended that I use one of the woofers to 100 hz and below to augment the Bass as running both at full range they would conflict in the midrange.

Any Help would be most Appreciated Thank You in Advance to any assistance anyone could provide Thank You !

I'm a big fan of active EQ...not passive so I'm not much help.
I am in somewhat a similar boat that I am beginning to put another system together
not too different than yours. Except I like simpler projects...yours is a beatiful but
could be a real gorilla in tweaking...but no doubt it might be worth it.

I'm thinking 511E but with GPA288H drivers...the high end is better methinks
so I do not need the ev tweeters...though gm may add that the ev tweeters bandwidth
may be more appropriate. Still I truly believe the fewer number of transducers...the better.
I'm thinking of the alnico gpa 416 speakers...I want brand new...that's just me.

But if I had 4-416's...then zilch's comments are spot on not just because that is exactly
what I would do. ;) But it makes me think I could design a 3 way system with the behringer
and maybe have some passive xo across one of the 416Bs to keep the other one focused to
the midrange horn....now you got me thinking!

[quote=Steve Mac;1829458]

Quote:

---

I am in somewhat a similar boat that I am beginning to put another system together
not too different than yours. Except I like simpler projects...yours is a beautiful but
could be a real gorilla in tweaking...but no doubt it might be worth it.

---

This is what I'm finding out and your right Steve I think it's worth it.

Quote:

---

I'm thinking 511E but with GPA288H drivers...the high end is better methinks
so I do not need the ev tweeters...though gm may add that the ev tweeters bandwidth

may be more appropriate.

---

I have a couple different pairs of 288's ,I want to use these because the diaghrams are Brand New

Quote:

---

Still I truly believe the fewer number of transducers...the better.
I'm thinking of the alnico gpa 416 speakers...I want brand new...that's just me.

---

1 pair of 416's are used but in great condition and the other pair I have are NOS still in the Altec Boxes.If I need to recone them (Used Ones) I will.

Quote:

---

But if I had 4-416's...then zilch's comments are spot on not just because that is exactly
what I would do. ;) But it makes me think I could design a 3 way system with the behringer
and maybe have some passive xo across one of the 416Bs to keep the other one focused to
the midrange horn....now you got me thinking

---

But I truly believe that 1 woofer cannot keep up with a 288 without having to shelve it completely it just overpowers and drowns out 1 LF transducer.In almost every Altec system that a large format driver is used 2 woofers are usually the norm.Let me know if you come up with anything !!

I'll send GM a email see if he can help Thank You Steve ! :2thumbsup:

I'm afraid I'm not going to be much help John.....It's going to take all my wits to come up with the new crossovers for my 19's even though I have the schematic!!! I'm a complete novice at this crossover stuff.

Having said that, I'll be following this closely though, as I think you are putting together a killer system here. What type of design are you going for with the bass bin?

I think the dual 416's will be awesome....are you thinking 500hz, 6K?

Quote:

---

Originally Posted by Altec Best

But I truly believe that 1 woofer cannot keep up with a 288 without having to shelve it completely it just overpowers and drowns out 1 LF transducer.In almost every Altec system that a large format driver is used 2 woofers are usually the norm.Let me know if you come up with anything !!

I'll send GM a email see if he can help Thank You Steve ! :2thumbsup:

---

passive yes...active no...the secret of my success have been the attenuators I use on the output of the behringer XO...that way I pump up the juice to the crossover but limit signal to the power amps. One big benefit of active is I can try hundreds of slopes/gains, eq,safety limiting, etc with the behringer... in effect I don't want the amp/speaker/xo to be tied together...it's just too limiting. I'm seriously considering an SET amp for the smaller system on top and with bi/tri-amping it's so much easier to mix/match and experiment.

I believe in your case you are trying to build the rod speaker right? If that's the case you need to research what they used for that project and tweak away.

Quote:

---

Originally Posted by J Henry

What type of design are you going for with the bass bin?

I think the dual 416's will be awesome....are you thinking 500hz, 6K?

---

I'm not sure yet on the bass bins I'm waiting to see what GM says about an over and under drivers with a sled on top for the horns.As far as the 511 horn I would like to see that go to at least 8k or 10k and then bring in the T350 around there.

Quote:

---

Originally Posted by Steve Mac

I believe in your case you are trying to build the rod speaker right? If that's the case you need to research what they used for that project and tweak away.

---

Similar to the Rod I prefer the drivers over and under GM built one like that if you check out his album on his profile page he has a picture of one with a 511 on top.I'm thinking something like that except with a T350 as a super tweeter too :D I talked to him yesterday but he is alittle under the weather right now Hope he gets well soon :2thumbsup: Thanks Steve :thankU: John

I'd suggest measuring the T/S parameters on your 416s before settling on boxes for them. Any two in one box need to be verrry close ITR. Impedance plots and matching that as well. AFAIK, the current kits are the one-size-fits-all 416C kit Altec was using when they quit, so if you recone any, you'll probably need to do them all for the best matchup, and even I would wince doing that to NOS Bs.

Another option to use what you have if they don't match well enough is a 4-box MTM.

Doing a passive XO for a 3-way with mid and HF horns of such vastly different dimensions... I wouldn't go there. Go active 3-way and dial in the XO and delay. Be aware though that not all active XOs offer delay for the HF.

Quote:

---

Originally Posted by bfish

I'd suggest measuring the T/S parameters on your 416s before settling on boxes for them. Any two in one box need to be verrry close ITR. Impedance plots and matching that as well. AFAIK, the current kits are the one-size-fits-all 416C kit Altec was making when they quit, so if you recone any, you'll probably need to do them all for the best matchup, and even I would wince doing that to NOS Bs.

Another option to use what you have if they don't match well enough is a 4-box MTM.

Doing a passive XO for a 3-way with mid and HF horns of such vastly different dimensions... I wouldn't go there. Go active 3-way and dial in the XO and delay. Be aware though that not all active XOs offer delay for the HF.

---

Thank You Brad for your suggestions Much Appreciated !!! :2thumbsup:

I've always used passives I know,I know, I got to get with the times :D Do you have a suggestion on make and model Active crossover as I don't have a whole lot of experiance on them and need your guys observations on such units and best way to proceed with this.

The last thing I want to do is recone those NOS they are just to pretty to do that too.Because if I did I would have to go and have my head examined.:( I've been saving them for a long time.And now is the time to break them out.Thanks again Brad for your Help !!! :thankU: John

You're welcome.

I've not used one, but this has all the bells and whistles;

BEHRINGER: DCX2496

Pretty popular among DIYers, just verify it'll do stereo 3-way.

The beauty is in the flexibility. Build a passive for that system and that's all it's good for. Considering how most of us are forever tweaking, I'd rather do it with software than a soldering gun and mail-order parts.

Quote:

---

Originally Posted by bfish

You're welcome.

I'd rather do it with software than a soldering gun and mail-order parts.

---

This is why I'm doing as much research as I possibly can to try and get as close as possible the first time.As long as I can keep "Murphy's Law" at bay for as long as I can I should be OK. But there is no guarantees as we all know.;)

Hey AB. I just got back from Ohio and the Midwest audiofest. I'm a bit toasted, but can be of more help tomorrow.

I'm sure we can figure out something.

Quote:

---

Originally Posted by bfish

You're welcome.

I've not used one, but this has all the bells and whistles;

BEHRINGER: DCX2496

Pretty popular among DIYers, just verify it'll do stereo 3-way.

---

Yes, it will certainly do stereo 3 way, but I've heard quite a few comments that the sound quality is not really up to scratch......the old digital/analog discussion.

What do you expect for $300?

A lot of users use these to find the correct parameters & then build their passives from those settings.

Yeah, the DCX is super handy for trying a lot of different things. I've done that a lot, then built passive.

I can certainly help here. I can send you my WT3 to do impedance sweeps, or you might want to pick one up. Getting good sweep measurements of each section would also be a big help. Do you have the hardware to do it?

I don't think I'd go below 700Hz 2nd order on the 511/288. Not sure for the top end.
And you'd probably want some underlap between the horn and bass section - 20~30%.
So first draft would be 600 LP + 800HP 2nd order. That's a starting point. Put an L-pad on the horn for level adjust. I would run the 15s in parallel if your amp can drive a 4 ohm load.

The 511 can be hot in the 500Hz-1K region, so that would need to be tamed via crossover or EQ.

What's your bass cab?

Quote:

---

Originally Posted by J Henry

Yes, it will certainly do stereo 3 way, but I've heard quite a few comments that the sound quality is not really up to scratch......the old digital/analog discussion.

What do you expect for $300?

A lot of users use these to find the correct parameters & then build their passives from those settings.

---

Some folks don't feel comfortable unless they empty their wallets too. ;)
I run digital into the unit...one D/A on the output and make sure I get a big signal into the crossover to get the resolution out of it. Most passives are effect processors(i.e. they have a sound of their own)... So, I think passives offer their own negatives as well. I just remember when my Dad played with his stereo back in the 60s that the crossovers stopped or limited tweaking all the time...and were more of a black art back when to those guys.

On top of all this are several tweaks that can be made to the dcx if you own one that will clean up the d/a and improve the clocking of the digital input. So rather than clean it up with passives....clean up the dcx and retain the high tweakibility factor. As they say though, YMMV....

[quote=Panomaniac;1829564]

Quote:

---

Yeah, the DCX is super handy for trying a lot of different things. I've done that a lot, then built passive.

---

Well I don't have one of those yet.

Quote:

---

I can certainly help here. I can send you my WT3 to do impedance sweeps, or you might want to pick one up. Getting good sweep measurements of each section would also be a big help. Do you have the hardware to do it?

---

I'm working on it and Thanks for the offer Pano I'll call you !!!

Quote:

---

I don't think I'd go below 700Hz 2nd order on the 511/288. Not sure for the top end.

---

I was thinking 800 to 1000hz to 8k to 10khz on the top and then bring in the super tweeter T350 for the UHF

Quote:

---

So first draft would be 600 LP + 800HP 2nd order. That's a starting point. Put an L-pad on the horn for level adjust. I would run the 15s in parallel if your amp can drive a 4 ohm load.

---

All drivers are 8 ohm Unfortunately at the moment I'm stuck with 8 ohm loads and would like to have an L-pad to adjust the horn and then could be taken out later after dialed in.

Quote:

---

What's your bass cab?

---

I'm still very early into this yet all drivers I needed I got now I was waiting for the EV T350's now they have arrived all I need is the XO's and cabinets.Which I have to build yet.I'm thinking a box with the rear corners tapered to push back into a corner with a over under 416 configuration.I haven't decided whether to separate them yet inside of box.It will look like one box from the outside but in reality it would be 2 stacked together.Zilch said they could interfere with each other in the midrange and he recommended to limit one of the woof's to 100hz and below.Basically to augment the other.I'm thinking I maybe able to get around that if they are separated.Any thoughts on this ? I would rather both woofer's running full range as I really feel the 288 needs it.But if i can't then I would have to follow his recommendation I guess,this is why I'm posting here for the guys with Altec experience as he said he was limited with Altec drivers he is familiar with JBL.

[quote=Steve Mac;1829566]

Quote:

---

Some folks don't feel comfortable unless they empty their wallets too. ;)

---

Well I've already done that acquiring the drivers and horns :eek:

Now I just have to shell out for the Crossovers and some Baltic Birch and fiberglass.

Quote:

---

I run digital into the unit...one D/A on the output and make sure I get a big signal into the crossover to get the resolution out of it. Most passives are effect processors(i.e. they have a sound of their own)... So, I think passives offer their own negatives as well. I just remember when my Dad played with his stereo back in the 60s that the crossovers stopped or limited tweaking all the time...and were more of a black art back when to those guys.

---

Well I'm hoping I don't have to tweak till the cows come home.:p I would like to get it close as possible the first time so the adjustments will be minor.As pano suggested I think a L-pad is almost mandatory when using a large format driver in a home setting.This is why I feel dual 416's are required to keep up with the 511/288's I have a 288/1005 right now on top of a 416B in a 612 cabinet and I can tell you I have to shelve the 288 all the way for them to sound good and they do.Extremely loud,same amount of power next to my 19's they are twice as loud as the 19's that tells me they are much more efficient than the 19's.Midrange is Awesome !!

Quote:

---

On top of all this are several tweaks that can be made to the dcx if you own one that will clean up the d/a and improve the clocking of the digital input. So rather than clean it up with passives....clean up the dcx and retain the high tweakibility factor. As they say though, YMMV....[/

---

QUOTE]

This is quite interesting Steve and haven't thought about this option which does make a lot of sense.However I was hoping to just be able to build a set of passives without having to shell out more dough other than caps,resistors,coils,etc...

As this is my first complete speaker build from scratch I could have chosen something maybe easier less complicated,but as my space is quickly disappearing from the large quanities of loudspeakers to the ceiling :D I thought I would try to build the Best one I could and be done with it and hang up my Saw.On second thought Nahh maybe Not

Well if I can complete this with the results I'm looking for I can start to thin the heard so to speak. :2thumbsup: Thank You everyone for your input and suggestions/help I appreciate as this is going to need the expertise of you gentleman.:thankU: Best Regards ~ John

Lacking published FR and polar plots for 511E/288, assuming they're the same as a 511B/802 on the bottom end is... well... an assumption.

Same for selecting an XO point before deciding on LF cab(s). You're seeking a near polar match for the LF/MF at XO. With the LF narrowing as F rises and MF widening as F lowers, there's gonna be a sweet spot where they ~match*.

(Besides, we all wanna see some 511E/288 plots)...:coffeedrinker:

Brainfurt; was there one in the old tech letters?

*Same goes for the MF/HF XO.

I thought you said you will be running 2x 416s per side. So together a 4 ohm load, right?
Don't worry too much about the interference of the woofers if you keep them under 1K.
Not to say that crossing one lower is a bad thing, it can give you a flatter response because you have 2 instead of one down low.

Measure, measure, measure. You do need to measure.
I guess I could lend you some gear, if you don't want to invest in your own.

Following along on this build since I'm attempting a lesser project, using only one 416-8b.
I've had really good luck with a Behringer CX-3400 crossover. My plans are to upgrade to the DCX 2496 when I am a little further along. I had been looking at how to get the same bass reinforcement as AB is trying to do, possibly using a different Altec woofer, ala 421 or similar. I am putting that on standby but I think two 416's would get a guy pretty well there in the bass dept.. Of course, some folks can never get enough bass.
Good luck with your project, AB!

Just a note....if you use one 416 for bass and one for mid bass/lower mid range...the efficiency gain is gone for the passive XO...right?

Yes and no, depends on how you look at it. If you want more bass extension, the 1.5 setup will do that. If you wanted the same flat response out of 2 woofers running the full bass spectrum, you'd have to attenuate the upper range anyway. So there goes the sensitivity.

The only way to keep the sensitivity up is to give up on the low end. That may be a reasonable trade off. All depends on what you want.

Lunch is not free.....

Quote:

---

Originally Posted by bfish

(Besides, we all wanna see some 511E/288 plots)...:coffeedrinker:

.

---

Me too I'm really looking forward to it.As regards to the LF cab I was kinda waiting for GM to give me some advice on cabinet. But he is alittle under the weather at the moment.I hope he is OK.

Quote:

---

Originally Posted by Panomaniac;1829626[QUOTE

]I thought you said you will be running 2x 416s per side. So together a 4 ohm load, right?

---

I am, 2 416-8B's perside.If I hook them up in parallel it will be 4 ohm in series 16 ohm so how do I keep this all 8 ohm.

Quote:

---

Measure, measure, measure. You do need to measure.
I guess I could lend you some gear, if you don't want to invest in your own

---

.[/QUOTE]

Or you can send me a shopping list, Another shopping list just what I need.;) I think you did tell me on the phone awhile back but can't seem to find what i did with that paper.Thanks Mike !!!

Quote:

---

Originally Posted by westend9

Of course, some folks can never get enough bass.
Good luck with your project, AB!

---

I'm one of them helps get my feet moving if you know what I mean.I love good clean distortion free bass.Thank You Kindly for the well wishes.After I get the help I need to get this going I will document for everyones reference.If it can help others in the future then that is a good thing !Thanks again :)

[quote=Panomaniac;1829667]

Quote:

---

Yes and no, depends on how you look at it. If you want more bass extension, the 1.5 setup will do that. If you wanted the same flat response out of 2 woofers running the full bass spectrum, you'd have to attenuate the upper range anyway. So there goes the sensitivity.

The only way to keep the sensitivity up is to give up on the low end. That may be a reasonable trade off. All depends on what you want.

---

Well I like all Bass, Mid-Range,and top end or HF/UHF But as these speakers are super efficient anyway wouldn't that still leave them pretty efficient with a flat response across the board ??? I will follow your recommendations as you guys are much more versed in XO's than I.

Quote:

---

Originally Posted by bfish

(Besides, we all wanna see some 511E/288 plots)...:coffeedrinker:

Brainfurt; was there one in the old tech letters?

---

Well it wasn't in the tech letters, it was in the old 9848 brochure. (courtesy Lansing Heritage)

(Added; the tech letters did give the 288/511 sensitivity rating, 105dB)

Yeah, 9848s used 411s, but the directivity of two vertical 15s should be a reliable constant, and you also have the directivity data from 700Hz-8K for the 288/511E.

All well and good, but it does raise the question, 'why didn't they do it with two 416s'...?

GM demo'd some 9848s I believe, I'm sure he'll have some positive input.

(Feel better soon GM). :)

Don't worry about the 4 ohm thing, in fact it's good if you're driving it with solid state.
The crossover will be done on the real impedance of the drivers, not just a nominal 4 or 8 ohms. And a 4 ohm load saves you money on inductors.

How much room do you have for the bass bins? You know I'm thinking Onken W. That would be killer, but takes up a lot of room. Where you going to do the side by side thing, or one up above the other?

Thanks to bfish for the link, it's a help. Crossover was 700Hz, that's good news and easy to do.

Sure, I can send a shopping list of measurement gear. You ready to take the plunge?

Horizontal woofs would "flip" the directivity, necesitating a different XO point (among other things), one that would defeat much of the reason for using a 288.

Why, wouldn't the horizontal woofers have a wider, shorter pattern? What was the monitor with 2 12s and the 811 horn?

Bottom line, what's the polar pattern of 2x15 and the 511 in the octave around 700Hz?

I guess I saw that coming, I was typing the following when you posted;

More on that...

A single woof radiates a fairly uniform, round pattern, which narrows with increasing frequency. However, when you put two in close proximity, the pattern becomes an ellipse, or for interpretive purposes, rectangular. The pattern is just the opposite of what your intuition would suggest though, with woofs stacked vertically, the pattern is wider horizontally, and vice versa.

This is borne out in the 9848 directivity plot I linked to. At 500Hz, the pattern is 135 degrees horizontal, and 60 degrees vertical. By the 700Hz XO point, the horizontal has narrowed to 90 degrees, and begins to blend with the 511 horizontal pattern.

So, if you flipped the woofs to side-by-side, the pattern flips too. You can see by the directivity plot how that won't meet the 511 polars at a reasonable frequency, with the woofs doing

xxx
xxx
xxx

and the horn doing

xxxxxxx
xxxxxxx

Yeah, Altec did side-by-sides too, but with a specific application in mind for which it worked. They also incorporated some directivity "steering" (via phase offset) into the design as well.

[/quote]bfish;1829687]

Quote:

---

All well and good, but it does raise the question, 'why didn't they do it with two 416s'...?
GM demo'd some 9848s I believe, I'm sure he'll have some positive input.

(Feel better soon GM). :)

---

I believe the answer is that 411's use a sealed enclosure and require slightly less volume than 416's in a vented box therefore Altec could keep enclosure smaller even at it's current size (9848) it is still 200 Lbs. 49" high 34" wide and 23 1/4" deep
I hope he feels better too! He said he had a chance to check out the thread.Hopefully he will be able to post soon on a cabinet design for the 2 416's, he has a nice picture of a dual woof cabinet with a 511 on top of it on his profile page.That is similar to what I would like to do except mine will have a T350 on top of the 511E.And I think his woof's are 515's.


quote]=Panomaniac;1829688]

Quote:

---

Don't worry about the 4 ohm thing, in fact it's good if you're driving i.t with solid state.

---

Yes I am at the moment running Solid State I needed more power.

Quote:

---

The crossover will be done on the real impedance of the drivers, not just a nominal 4 or 8 ohms. And a 4 ohm load saves you money on inductors

---

That works any savings will be great.

Quote:

---

How much room do you have for the bass bins? You know I'm thinking Onken W. That would be killer, but takes up a lot of room. Where you going to do the side by side thing, or one up above the other?

---

The Onken W won't work as they are going in the corner they can be as tall as the ceiling :D But space is limited so I would rather go up instead of across smaller footprint.So as Brad said one above the other is the right choice for me.

Quote:

---

Thanks to bfish for the link, it's a help. Crossover was 700Hz, that's good news and easy to do.

---

I second that. Thank You Brad!!!

Quote:

---

Sure, I can send a shopping list of measurement gear. You ready to take the plunge

---

Soon I'm thinking around the first, second week of August. I have a couple jobs to undertake first.Have to pay the bills first.After that I think I may take a few days off between jobs to get started.My lumber yard can have the Baltic in 1-2 days so that leaves the XO and again I'm just waiting for GM's recommendation on cab design.I'm just going to build a sled for the 511E/288 with the T350 on top of that.It will make it a whole lot easier moving it around as well.

I want to Thank, You Mike and Brad, for your assistance on a proper course of action. :thankU:

Cool, vertical it is!

I'm about to hit the road for Pigeon Forge and Dollywood. Got to pick up a pair of 1005 horns. Yahoo! Talk to y'all later.

Let me know when you get back Pano.You can send that list anytime, I need to see how much these things will cost.May have to look for some bargains :( Save the money for the parts,wood,etc...

Heres an offer. Bring your Baltic birch and a cutting list up to Ridgefield Ct, and I'll cut all the pieces for you. Takes about a minute a piece and they will be perfectly square and true. It will cost you a 6 pack of good beer. The offer stands for all of you local guys.

Ed

Wow! What a great offer. It' wonderful what you can do with a good table saw and a guy who knows how to use it.

But what do I do with my table saw and router table and all my tools.;)

I have a better idea how about I'll build them throw them in the back of my truck and drive up there for a listen oh yeah and I'll pick up a couple cases of beer,I like that idea better.:D Do you have a good amp !

Sounds like a better plan.

My amp situation is pretty lame - but this could be the excuse that I've been waiting for....

Ed

Quote:

---

Originally Posted by Altec Best

Now I talked to the Zilchster and he recommended that I use one of the woofers to 100 hz and below to augment the Bass as running both at full range they would conflict in the midrange.

---

There's some definite advantages to this when the XO point is > ~1 WL away from a dual driver's acoustic center and you're not far enough away from the speaker(s) to make it a moot point, so at a glance the way around this is to either use a vertical MTM or horizontally opposed layout depending on the app.

WRT mids confliction, I don't recall this ever being an issue with either the 500 or 800 Hz versions using horizontally opposed woofers plus it has the advantage of being able to control directivity to a lower frequency in the horizontal plane, so if the space permits, this is my preferred dual woofer layout.

GM

Quote:

---

Originally Posted by Steve Mac

I'm a big fan of active EQ...

I'm thinking 511E but with GPA288H drivers...the high end is better methinks
so I do not need the ev tweeters...though gm may add that the ev tweeters bandwidth
may be more appropriate. Still I truly believe the fewer number of transducers...the better.

---

Me too, with the caveat that there's a certain synergy of matching a compression horn's impedance, so I prefer passive CD horn EQ when driven with a very low output impedance source.

When it comes to the highs, it's mostly about what sort of power (polar) response is required and how much EQ is required to contour a mids horn to do double duty as a super tweeter.

I felt the same way until I auditioned DSL's three way SH-46 awhile back.........

GM

[quote=Altec Best;1829472]

Quote:

---

Originally Posted by Steve Mac

But I truly believe that 1 woofer cannot keep up with a 288 without having to shelve it completely it just overpowers and drowns out 1 LF transducer.In almost every Altec system that a large format driver is used 2 woofers are usually the norm.Let me know if you come up with anything !!

---

That, or horn load a single to produce the output of two with the trade-off being a truly huge cab if loaded enough to match the dual woofers down low.

The question though is whether or not the 288 has enough dynamic headroom left once shelved to meet the needs of the app. For prosound it doesn't, but for HIFI/HT apps it should except for maybe the 'Headbanger's Ball' types.

GM

Quote:

---

Originally Posted by Steve Mac

... in effect I don't want the amp/speaker/xo to be tied together...it's just too limiting. I'm seriously considering an SET amp for the smaller system on top and with bi/tri-amping it's so much easier to mix/match and experiment.

---

Agreed, though I prefer lots of Class A or at least very low -fb SS power with passives to impedance match to compression horns to keep from clipping transients.

GM

Quote:

---

Originally Posted by Altec Best

I'm not sure yet on the bass bins I'm waiting to see what GM says about an over and under drivers with a sled on top for the horns.As far as the 511 horn I would like to see that go to at least 8k or 10k and then bring in the T350 around there.

I talked to him yesterday but he is alittle under the weather right now Hope he gets well soon

---

FWIW, I've periodically mentioned that my current speakers are anything but optimum. They are the original 'subs' used to fill in below chopped up 210s except with ~stock 511/808-8a loaded with Ultralights to effectively make them 802-8A. As such, they suck by my standards, sounding best from outside the room and even then, music scales obnoxiously 'walk' up-down between the horn/woofers and some musical instruments sound way too tall due to the acoustic centers being so far apart for a N501-8A.

WRT adding super tweeters, ideally you want to match the two horn's polar responses at least around the XO point, but I've never seen any published plots of older speaker components other than Altec's, so typically requires lots of trial n' error if no measurements are made.

Thanks, though for me, getting 'well' these days means not feeling as bad as the day before.

Quote:

---

Originally Posted by bfish

I'd suggest measuring the T/S parameters on your 416s before settling on boxes for them.

AFAIK, the current kits are the one-size-fits-all 416C kit Altec was using when they quit........

Another option to use what you have if they don't match well enough is a 4-box MTM.

Doing a passive XO for a 3-way with mid and HF horns of such vastly different dimensions... I wouldn't go there.

---

Agreed, though not a big deal in most sealed apps. Vented is a different matter since even the dissimilar path-lengths between the drivers and vent accepts power sharing. In extreme cases, I've seen one woofer 'hog' most of the power, causing it to audibly distort due to both thermal power compression as well as over excursion while the other woofer is mostly acting as a passive radiator. For most HIFI/HT apps using large HE woofers though, it's normally not a concern.

Still, when the desired driver/vent layout allows it, putting each driver in its own vented 'cab' is a good plan if for no other reason than the divider makes for a much more rigid cab and each can be individually tuned/optimized.

Bummer, guess if I ever need one of my 515Bs re-coned I'll have to sell them.

4 box MTM?

Yeah, been there, done that way back when and why I swapped 805/288 for 511/802 to get a satisfactory HF response and later adding a second pair to get the larger horn combo's more robust mids to 'have my cake and eat it too'.

GM

Quote:

---

Originally Posted by Panomaniac

I don't think I'd go below 700Hz 2nd order on the 511/288.

---

Why? I mean a 288 on a shortened 511 is from an acoustical loading POV about the same as an 802 on a stock 511, so a 500 Hz XO is appropriate.

GM