DALI MEGALINE AMPS & CROSSOVER


I have recently purchased a pair of used(2nd owner) Dali Megaline speakers for a can’t pass up/ridiculous/unbelievable/put a smile on my face low price. Being a fan of ribbon Apogee speakers(currently own Studio Grands) I have high hopes for the Megalines since are more dynamic, taller & do home much theater better. I have a 100” projection screen but need to upgrade to a 125” because the gargantuan Megalines make the 100” small!   Anyway, I’m in need of some advice on what crossover & amps to use with them. I tried the Dali x-over but don’t like the sound of the x-over point of 1200hz along with a shallow slope. So I’m using a Beringer Ultrapro24/96 x-over right now at 800hz at 48db. But I know I can do much better than the Beringer or should I have the Beringer modified?!. On the amps right now I’m using digital(Merrill Veritas 400watts) on the woofers & Coda S5(class-A 50watts) on the ribbon. Sounds amazing already! But I know it can sound a lot better but don’t want too(can’t afford!) to spend more than $15-$20K. So, first please guide me in the right direction for a quality 2 way or 3-way x-over under $2K. Right now I’m looking at the DBX Venu360. I really want to do better than that but not sure what is out there for that price. Then for the amps, I really like & think a pair of stereo PS Audio BHK Sig 250 would be awesome! Being they are tube input(sweet sounding) & solid state(punch you in the face) Mosfet output! They have been getting fantastic reviews. Or maybe 4 of the new Benchmark AHB2 ran in mono, or a pair GamuT D200i’s, or should I get two more Merrill Veritas mono amps, so many possibilities! I want amps with balls(home theater) & also sweet sounding(I love music!). I’d rather stay away from all tube amps also due to hat issues here in hot NorCal. BTW- I also stuffed EACH cabinet with 3 pounds of Acousta-Stuf due to lack of cabinet damping. I really think these are going to be my dream speakers for a very longtime. Once properly setup I may never leave the house again! : -) Any & all suggestions would be greatly appreciated! Thank you!!

ptheo
Can’t help with the crossover, but as for amps, since you know and seem to like the sound of the S5, have you considered a pair of Coda 15.5s, or possibly some of their higher-powered monoblocks? Or maybe even their System 150? I’m a BIG fan of Coda (especially their power amplifiers). I think they make some of the finer SS amps going. The right model will drive those Megalines (which I’ve heard several times) with a lot of balls and just the right amount of sweetness. At least, IMHO. Maybe a call to Doug Dale at Coda would be in order?
ptheo,
i am an Apogee user myself (Scintilla 1-ohm version. love this speaker & haven't considered life after Scintilla....)
One thing you could do is contact Agon member "albertporter". he used to own the very same Dali you have & you can ask him how he had his setup. Right now he's using the largest JM Lab speakers. 
Thanks. 

Albert had a custom tube crossover made of which he was emphatic that it made a huge difference- by comparison the stock crossover was so much junk. The crossover was built by Tom Tutay who does not go on the web- you have to call him. The last number I have for him is 850-244-3041 which appears to be current.

lynott- Yes you are correct Coda makes great amps & a pair of the new S150 may just be the ticket. My main complaint about the S5 is the low power output not the killer sound. ! I will call Doug the man tomorrow. But for some reason I’m really smitten is curiosity about the PS Audio BHK SIG 250 being it has the sweet sound of tubes with the drive of a SS which I feel would sound awesome on the MEGALINES with the ribbon tweeter. I may start a thread in the amp section asking about it. Maybe a combo of both Coda on the bottom & PS Audio on the top. But I’ve read from Albert Porter’s thread it imperative amps must be the same! May I ask lynott where have you heard the MEGALINES many times & under what conditions?

 

bombaywalla- The Scintilla is an amazing speaker that I heard many times at a friend’s house. Even better than my SG’s! I’m currently reading AP’s thread(pg91 of185) on the MEGALINES. Great thread about many things audio. I will be attempting to contact him soon to pick his very knowledgeable brain about the amps/crossovers he has tried.

 

atmosphere- I called Tom Tutay today about spoke to him about his tube crossover. Very nice guy & I’m sure it sounds great! But I don’t think that is what I’m looking for at $4K. It’s fixed at the stock crossover point(1100hz) with the shallow slope the match. I want to be able adjust the crossover & slope on the fly to suite my tastes. Check this out:

http://www.newformresearch.com/index.php/planet-audio/the-best-of-the-best/crossovers

 

Thanks guys for the input!

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ptheo:

For the sake of perfect continuity, *I* would probably stick with the same make of amplifier for top and bottom.

Haven't heard the BHK, but it is getting some nice reviews. A buddy of mine was actually considering the 250, but I think he's currently leaning toward Boulder.

I've heard the Megalines a total of three times , including twice at the same person's house. As I recall, he had them driven initially by pairs of Paraound JC1s, then by big Pass stereo amps. The other person was using Classe Omegas. In both cases, if I'm remembering correctly, the stock crossover was used. 

I remember the speakers sounded HUGE (at least compared with what I was running at the time), and that impressed me on some live Deep Purple, in particular. 
Funny... I just upgraded my modded by Audiosmiles in the UK  Behringer Ultra Pro for the DBX 360 (tweaked by Roger Sanders).  The Behringer/Audiosmiles unit is awesome. If you are interested, I can let it go pretty cheaply.  
I ran Dali Megaline for more than 10 years, tried multiple amps on them and got different results with each change. Short answer is you must use same amps on both top and bottom, otherwise nearly impossible to get fully integrated sound.  

I tried various amps, both solid state and tube and quickly found the big VTL 750 was was making better sound.   In fact, when the VTL 750 was on ribbons that is where the best sound was coming from.  Reverse and put the VTL 750 on bottom and it was better sound than top.

In other words if the woofers had the big tubes it sounded better than the ribbons (you could hear the mismatch).   Reversing got the same effect. Believe me, I was trying desperately to not buy two pair of big tube amps but that's what it took to get the Dali world class.  

My (now) Focal Grande EM are certainly better and simpler set up but I still have one guy in my group that misses my Dali Megalines with four VTL 750 and twin JL Audio subs.  

Solid state might exercise a little better grip on the woofers but they are only approx. 6” and very quick and controlled already.  They are more in need of what tubes do. 

I no longer own VTL but they were a great amp, especially for that time.   I ran VTL 750 on my Soundlabs, then the Dali Megaline and for the first year with big Focal Grande EM.

The new VTL Siegfied is better than the 750, and so is the Allnic M3000, Allnic M5000,  ARC Ref 250 and probably other more current design tube amps.   I would go for at least a couple of hundred watts on each of the four positions needed to operate the Megaline.

Last, the crossover that Tom Tutay builds is a huge upgrade over the stock one but does so without risk to the Dali design. The crossover point is indeed fixed but the flange point of Tutay crossover allows varying boost / cut of low frequencies via silver contact volume control switch, allowing you to tailor the sound to your room and compensate for distance from wall and corners.

Remember, there are capacitors in the base of the Dali Megaline that the signal passes through to make the crossover operate properly.  When you choose different EQ or crossover from factory specification you risk damage to the tweeter.

The 7 foot tweeter already dips below 1000 HZ which is very low frequency for a ribbon to have to operate.  I believe if you put in enough power and operate at frequencies below what it was designed for,  you might be inviting problems.

If you follow your own path to crossover points and EQ, I suggest you order replacement ribbons from Dali while they are still  available.  You probably already know this model is discontinued and is why I sold mine and went to Focal.

I agree lynott, one would expect going from digital amp(bass/mid- cone driver) to class- A amp(treble- ribbon) ones asking for trouble.  I’m sure any of the amp brands you mentioned above would sound great. Especially the Boulder & Classe Omega with their endless power reserves.

I can’t wait to hear some Deep Purple on these bad boys once properly setup! They were my first rock band back in ’72 at 10 years old! Highway Star!

Please send me info on the mods cerrot. I’m curious how much better/different the DBX 360 is?! I may even call Mr. Sanders since his speakers include an electronic crossover. Nice setup  

Thanks for chiming in Mr. Porter, I enjoy reading you thread very much! I have some many questions I want to ask you about the ML’s I don’t know where to start. But let me reply to a few comments you made. I know matching amps has to be better, but what’s amazing right now I have two different type/brand amps, two different length(4’ & 8’)/brand( MA-ANAP & AQ) speaker cables with cheap banana connectors, two different(one cheap, one good) interconnect brands, & last but not least the Beringer crossover & the system sounds AMAZING! The ease/clarity of the dipolar ribbon sound from the ground to the ceiling, the unlimited dynamic range sledgehammer bass, only one crossover electronic point adds up to the best speaker I have ever heard or owned. I can’t wait to get it all setup correct. How you ever went back to a point source speaker after the ML’s Mr. Porter I’ll never know.

Can you please explain to me why the 6” woofers are ‘more in need of what tubes do’? Never heard that before although I don’t doubt you for a moment!

Also, you mention the caps in the base are ‘to make the crossover operate properly’. I though the caps are to protect the ribbon from DC current back to it?

Regarding the lower crossover point with a stepper slope, if I’m not mistaken, my Apogee Stages crossed over at 800HZ at 6/12DB & My Apogee Studio Grands crossed over at 600HZ same slope with much smaller ribbons. Why can’t the Dali ribbon which is 91” tall do 800 say at 24DB?!

I will look into replacement ribbon for peace of mind because I don’t ever see me selling these speakers since that can’t be topped. Period.

Do you have any comments of me adding 3lbs of stuffing to each cabinet?

BTW- I did have them crossed over at 60HZ at 24DB with my subs, but didn’t like the bass. So now I’m running them full range & blended the subs in up to 50HZ. WOW is all I can say. I will be up again tonight until 3AM like every night for the past two weeks since I have had the speakers with my jaw ajar in disbelief!

 Check this out about the Beringer I’ve been disrespecting:

http://www.audioheritage.org/vbulletin/showthread.php?17457-Behringer-DCX2496-digital-x-over-any-good

http://freerider.dyndns.org/anlage/evaluierung.htm

Ptheo - here is a link to the modded Behringer.
http://www.behringermods.com/dcx2496.html

It is a sweet unit.  I upgraded to Rogers modded DBX as it has room correction (only used for 500 hz and below) and totally BLEW ME AWAY.  

How you ever went back to a point source speaker after the ML’s Mr. Porter I’ll never know.

Can you please explain to me why the 6” woofers are ‘more in need of

what tubes do’? Never heard that before although I don’t doubt you for a moment!

Also, you mention the caps in the base are ‘to make the crossover operate properly’. I though the caps are to protect the ribbon from DC current back to it?

Regarding the lower crossover point with a stepper slope, if I’m not mistaken, my Apogee Stages crossed over at 800HZ at 6/12DB & My Apogee Studio Grands crossed over at 600HZ same slope with much smaller ribbons. Why can’t the Dali ribbon which is 91” tall do 800 say at 24DB?!

I will look into replacement ribbon for peace of mind because I don’t ever see me selling these speakers since that can’t be topped. Period.

Do you have any comments of me adding 3lbs of stuffing to each cabinet?

BTW- I did have them crossed over at 60HZ at 24DB with my subs, but didn’t like the bass. So now I’m running them full range & blended the subs in up to 50HZ. WOW is all I can say.


I understand your comment about the difference between line array and point source. That is exactly what I miss about moving from Dali Megaline to Focal.

That said, the Focal is a better speaker, and should be considering the difference in cost. There is no perfect speaker, all are a compromise and overall there are at least half a dozen speaker designs that quality for best of best and dozens more that are almost in that category.

My comment about the 6” woofers refer to punch, power and foundation that makes music satisfying. It’s impossible to get 6” woofers to punch like the Focal 16” field coil but big powerful tube amps help close that gap.

If you use solid state on the Dali woofers you are likely hungry for more slam and weight and crossing the sub higher provides some of that.

If you look at Dali chassis and rear port design the free air resonance is about 35 HZ. It’s very difficult to get the speaker (any speaker) to continue output below that natural physical restriction.

Dali does an EQ that partially corrects that but it’s not possible to get it linear to 16 HZ like the Focal nor should anyone try.

Your comments about crossover points probably relate to this as well. When I ran my Megaline I had them operating full range and then brought in twin JL Audio F212 subs at 24 DB per octave at 30 ~ 35 HZ and no phase or EQ dialed in on JL sub controls.

The way I choose to run, the Dali operates on it’s own and the subs do the same. At this low frequency the Class D amps in the subs don’t seem to effect the sound of the Megaline woofers, provided you filter the Class D amps at AC level and preamp level.

I had a buffer built so my preamp could not “see” the Class D subs and used Purist AC cables with network boxes.

The caps in the bottom of the Dali are part of the crossover and are supposed to protect against someone hooking up the crossover or amps in reverse. In other words, when someone puts woofer signal into ribbons the hope is to block signal before damage. These caps are always in the circuit and part of crossover frequency.

You ask about comparing Apogee versus Dali ribbons. These are two completely different designs. If you put big power into the Megaline, even with stock crossover and room light is shining on ribbon surface, you can frequently see the ribbon shimmer side to side, partially out of control.

I think it’s a miracle Dali designed such long ribbons and keep them operating perfectly but I would not want to exceed factory specs on range they operate in, any more than I would consider passing red line on a car engine repeatedly.

I have no comment on stuffing cabinet, I never tried that. The cabinet does seem a bit lightweight when you knuckle tap on it but I loved the sound so much I left it as is.  Think hollow body guitar versus solid body :-).  I believe Dali took this into consideration in the overall design. 

I had plans for even more mods and upgrades on the Megaline before I changed over to the Focal.  One included replacing built in spikes for Still Points.   Also wanted to change those caps we’ve been discussing, the ones in the base of the speaker.   Better quality could drastically reduce distortion on ribbons but suspect it would wind up needed a separate box  wired up outside the chassis to accommodate.

Also wanted to go further on the Dali-Tutay crossover, I was at third generation and was still coming up with design changes that were significant to sound.  The last thing I did was drastic, 1% copper foil Teflon caps for Tutay crossover.  The caps were a fortune to get built but was amazing upgrade.


cerrot- I checked out the website(in UK) & looks very professional with proof in the graphs. I’m curious what difference & how much of a difference you heard of the stock unit? I just may want it for the right price! ; -)

Mr Porter- I agree the Focal Grand Utopia EM is an awesome speaker(although I’ve never heard it but want to) & superior in many ways as you mentioned given the major price difference. I could only imagine what killer 16HZ linear bass they have with the 16” EM Focal woofers! (BTW- I love the stealth piano black look & wish the ML’s came in that finish) But, a point source speaker is a point source speaker no matter what the costs or material or design.  To me, nothing compares to a line source dipolar ribbon.

I didn’t mention that my subs are a pair of the new JL Gotham V2’s(I owned F212’s in the past) so I have no need for the ML’s to go lower 35HZ.. So combining them at 60HZ at 24DB with the ML’s 24 6” woofers running fullrange down to 35HZ is giving me more ‘sledgehammer slam’ factor than I ever heard or imagined being it at loud or low volume. In fact, try any track(especially at the beginning of #11 ‘Sifting’)  from Nirvana’s Bleach & listen at the kick drum. In the past 30 years with any speaker I have owned with this track there would be a loudness level  were distortion would set being it from the amps or driver(s) hitting there limit. Not so with the ML’s 24 6” woofers! In fact when it was slamming hard I checked the woofers & they were barely moving! The combo with the low distortion big JL Gotham woofers & low distortion mid/high bass ML woofers is just freakin’ incredible! BTW- My room is 17’Wx26’Lx8’H.

Regarding driving the ribbons beyond there limit is something I want & will avoid as I had to replace one of my first pair of Apogee Stage ribbon’s(back in 89’) after burning it up in the past when it arced to the protective mesh due to over driving it. When I went to audition the speaker at the previous owner’s house the ribbons were flapping loosely on a simple vocal tune with the stock crossover. I thought they were loose & I would have to adjust them when I got home. But when I hooked the up to the Beringer at 800HZ at 48DB the ribbons have not moved at all even when cranked up! So if they don’t move at all I should be fine should I not?!  

Also when I auditioned them with a close friend who is an audio engineer(former Threshold & Coda designer)  is much smarter than me & is a bigger audio nut than me noticed a hollow sound to then right off the bat. He knew right away what it was which is no damping material in the cabinet what so ever. Since the stock crossover is set at 1200HZ with a shallow slope we were hearing it echoing in the cabinet. So stuffing the cabinet & crossing it over lower with a much steeper slope cured that bigtime as my engineer bud recommended & knew. Yes, I’m sure stuffing the cabinet will affect the low bass slightly but that is not an issue with the Gotham’s!

I too want to replace the spikes in the future & Stillpoints would be perfect. I will have to go into more detail on how you planned on doing that & along with the cap replacement you mentioned. I was wondering also Mr. Porter if you were unsung the provided template as a listing guide?

Still up in the air on what perfect crossover I will be using in the future………

Ptheo, the modded unit was quieter than the unmodded.  They disconnect outputs 1 & 2 which keeps things further from the part of the unit where noise can come from.  It was black as night and totally transparent.  I would probably let it go for $550 + shipping.  Still have the box.  Not a scratch on it.  
I had plans for even more mods and upgrades on the Megaline...wanted to change those caps we’ve been discussing, the ones in the base of the speaker.   Better quality could drastically reduce distortion on ribbons but suspect it would wind up needed a separate box wired up outside the chassis to accommodate.

Hi Albert,

Can you elaborate on the caps?
ptheo -- thanks for starting the thread!  ;-)

Vbr,

Sam



You bet Sam! Thanks for chiming in fellow Megaline owner!

Yes Albert, please elaborate caps mods & other upgrades for the Megalines?! 

BTW- I'm using a PS Audio BHK 250 amp on he ribbons right now & it sounds magical!