active 4345's

[gasfan]

Hi all. Can someone help me with running a pair of 4345s through a Behringer DCX 2496? There's only 3 channels but they're 4way. Any help is greatly appreciated.

[Robh3606]

Set them up to biamp.


Rob:)

[gasfan]

Okay, but I have no networks. I'm building these from scratch. Using 2441/2390, and 2206.

[Robh3606]

Well if that's the case can't you switch the 2496 to mono and purchase a second one to cover the other channel?


Rob:)

[gasfan]

I can't locate a usable manual for the 2496. Would I then have 6 available channels per 2496? I would much prefer someone build me a pair of networks and bi-amp them. Anyone here you might suggest?

[grumpy]

http://www.behringer.com/assets/DCX2496_P0036_M_EN.pdf

[gasfan]

I've already found this site. Problem is that it's deliberately obscured rendering it unreadable.

[hjames]

Manual looks clean enough to me.


http://www.behringer.com/assets/DCX2496_P0036_M_EN.pdf


I've already found this site. Problem is that it's deliberately obscured rendering it unreadable.

[gasfan]

Really! All the letters are covered with boxed X's. What's up?

[hjames]

Really! All the letters are covered with boxed X's. What's up?
Then you need to update/upgrade your PDF reader or something on your system.

I had checked the Behringers PDF file from work on a Windows machine and it was fine,
then after your post I just checked it with my OSX (Mac) machine at home and it looks fine on that too.

If there is a problem its on your system.

[Serum]

For a 4-way setup, you'd need to either use a conventional crossover for the mid/high section or make it entirely active, using 2 dcx2496's.
One 'problem' you need to address; you need a volume control for the DCX. The best way to use the DCX is with the digital input;

If you use an analog source, the DCX needs to convert it to digital, and again back to analog. If you use a digital source, the extra conversion isn't needed.
However, when using a digital input, you need to use some sort of volume-control. A digital volume control is a compromise, it looses detail if it's used at a lower level. I'm using a DCX with a volume control kit in the analog output, which works like a charm. This kit removes the hiss the normal DCX output creates. (my 106db 1w/m drivers only have a slight hiss, when you listen directly in the horn) with the stock one it suffered serious noise.

here (https://picasaweb.google.com/112333802006671383079/BehringerDCX2496VolumeControl) is the link to a few pics of this volume control board.

Another option is a minidsp, it has got more than enough inputs, and is available in a ready to run enclosure.

http://www.minidsp.com/onlinestore/detail/15-minidsp-in-a-box/flypage/90-minidsp-4x10-hd?sef=hcfp

It's also available with more inputs. Reason i chose for the Behringer is because it uses good quality DAC's and with the volume control PCB, the volume control should be a better grade. (and i used it for an active 3 way, not 4 way, like yours)

[gasfan]

For a 4-way setup, you'd need to either use a conventional crossover for the mid/high section or make it entirely active, using 2 dcx2496's.
One 'problem' you need to address; you need a volume control for the DCX. The best way to use the DCX is with the digital input;

If you use an analog source, the DCX needs to convert it to digital, and again back to analog. If you use a digital source, the extra conversion isn't needed.
However, when using a digital input, you need to use some sort of volume-control. A digital volume control is a compromise, it looses detail if it's used at a lower level. I'm using a DCX with a volume control kit in the analog output, which works like a charm. This kit removes the hiss the normal DCX output creates. (my 106db 1w/m drivers only have a slight hiss, when you listen directly in the horn) with the stock one it suffered serious noise.

here (https://picasaweb.google.com/112333802006671383079/BehringerDCX2496VolumeControl) is the link to a few pics of this volume control board.

Another option is a minidsp, it has got more than enough inputs, and is available in a ready to run enclosure.

http://www.minidsp.com/onlinestore/detail/15-minidsp-in-a-box/flypage/90-minidsp-4x10-hd?sef=hcfp

It's also available with more inputs. Reason i chose for the Behringer is because it uses good quality DAC's and with the volume control PCB, the volume control should be a better grade. (and i used it for an active 3 way, not 4 way, like yours)
You've lost me regarding the volume control. Is the DCX not governed by the pre? I thought I saw a few words on the manual I was able to make out regarding a quasi 4th channel possible somehow. Can you clarify this?

Thanks,
Peter

[Serum]

Governed by the pre; yes, if you use the analogue input and accept the losses. (if you are playing from a CD, you have a DAC in your CD, send it through your analogue volumecontrol, the berhringer will make it ADC and DAC again.

The dcx2496 has got 6 outputs; not more. if you want an active 4 way setup, you need two of these devices. (you will have 2 outputs per device unused)

You can't use 1 device for a stereo 4 way active crossover, like planned.

You could also use it as a 3 way active crossover and use a passive crossover between mid/high.

The minidsp i posted earlier does have the ability to be used as a stereo 4 way.

[gasfan]

Okay, got it. What are your thoughts on connecting the 2405s directly to a stand alone amp?

[Serum]

That would be an option too, but you would need a passive x-over network for that tweeter. and you can't time-align it to your woofer/mid. (the behringer has an auto time-alignment function, i like that feature myself. be carefull with it; use a capacitor on your tweeter/mid driver when using this, as far as i know it uses a full-range test signal for this..) I understand that another behringer is out of the question?

What amps are you using? some amps have got a x-over build in.

[gasfan]

A second Behringer is clearly the best option. No problem qcquiring one of those but I'm sure I saw something regarding a possible 4th ch.X2 with the Behringer. I can't access the manual presently till I deal with an apparent problem with my system. I will be using 3 Acoustat TNT 200s and a TNT 120, all upgraded and rebuilt by Roy A. Esposito of Sounds Like New. He was part of the engineering team that designed these amps. Power wise they're way overkill but the amps are state of the art and probably the best sounding ss amps I've heard in over 30 years. Their speed and bottom end control are second to none. Imo very close to reality. I had an Oppo BDP95 delivered yesterday to replace my old Rotel CDP. Very nice sounding player. My pre is a Meridian 501. I'm about to put together a pair of altered 4345s in 12 cubic foot cabs, 2206s for mids, and 2441/2390s for horns. I'm on the hunt for a cabinet maker willing to take them on. I can't seem to get anyone to return my call with an estimate.

[Serum]

That's a nice collection of amps! and sweet BR disk. :)

I've made an active 3-way, with integrated amplifiers. (Hypex) using the DCX2496 with a volume-control kit. It uses a Limmer 042 horn for mid/high, with a 1" beyma compression driver, Eighteensound 6nd410 mid and a 15" RCF (L15P400) for lows.



https://picasaweb.google.com/112333802006671383079/BehringerDCX2496VolumeControl

That's the volume-control add-on.

This is what the set measures like on the listening-spot; The bump at ~400 hz is gone now too. it was a cross-over boost from the mid and low driver.

Can't help you out on the cabinets though, there are quite a few miles separating us.. :) Have you got cabinet plans handy? I've use a blue HPL from abet laminati for a rebuild of a set 4312a's (i'll get some better pics of that)

https://lh5.googleusercontent.com/-r56LYGiGN9w/UD_MLc3EYOI/AAAAAAAACsc/dRMQgu1pAgw/s800/Schermafbeelding 2012-08-22 om 22.25.16.png

[gasfan]

I'm no expert but that response curve looks close to ideal. Not sure I could handle that conversion but I really like the versatility of the Behringer. Did you build your Hypex trio? Roy rebuilt mine with mono switch and balanced input option. Like the Hypex mono kit, they are now distortion cancelling circuits. In mono they put out over 1100 watts each. I've asked him to build me a pair of passives by the seat of his pants. No word on that yet. BTW, a friend of mine is on her way over there for the flower festival. If you see her say hello for me. Her name is Michelle. She'll be riding a bike.

Regards,
Peter

[Serum]

Yeah, it passed my by without notice. It's that time of year here. flower By bike, i think you mean motorcycle?

That's a suitable amount of power. :)

Hypex is pretty straight forward stuff; you buy a power-supply, amp modules of them, some wires and all you need to add is the heatsink. The power supply also has a build in DC protection detection, and a remote on/standby signal.

here are the heatsinks i'm using;

https://lh3.googleusercontent.com/-fQuIE8yrkwE/T-chiRI63RI/AAAAAAAACgo/psGU7ADi5NE/s800/IMG_20120624161723.jpg

This is the mid and high amp, should be ~ 100 watts RMS @ 8 ohm, more than enough for the units i'm using.
https://lh3.googleusercontent.com/-9viZSgbDelQ/UBO-MSO--rI/AAAAAAAACkw/Dti284gipZ4/s800/midhoog.jpeg

This is a bridged low-amplifier, which is capable of 800 rms@ 8 ohm.
https://lh6.googleusercontent.com/-rNecGYzGYm8/UD_LjrhEzyI/AAAAAAAACrw/DCZeTC4k-6M/s800/SDC13362.JPG

these are the amps in place in the speakers;
https://lh4.googleusercontent.com/-_2YetuKG8gQ/UD_Lf681d5I/AAAAAAAACrg/tdILCWrJeOM/s800/SDC13369.JPG

[gasfan]

Very nice. Looks like they could double as mounts for a Harley. The Hypex amps have very good reviews. Not sure I would be pleased with the "forward" character of class D. I have not auditioned any as yet. No, I mean bicycle. I thought that's what everybody got around on over there.

[Serum]

I'm (was) sceptic to this class-d as well. you normally always hear this typical non analogue sound, (heard a NAD set on an audio-show, didn't know it was class D, i asked the 'showmaster' if it was a class D amp. "Noooo, no class D, don't let the engineers here that", he whispered. "This is a Direct Digital amp" Bingo, was my first reaction.. You could hear it, especially in the higher regions of female voices, like Dido's safe trip home. (good recording, imo) But these hypex amps have got a very friendly/natural behavior.

Yes, i'm an enthusiastic biker myself, too. (although i have seen quite a few cyclists in Canada as well, who seemed to take it very serious :) ) Weather here is OK, not too bad. Autumn has just started.

The hypex amps are fair cheap. They currently reduced the prices on the switching power supplies, you can have an amp now for about 250 dollars. I'm using the higher grade editions for mid/high and the lower models for lows. Even in brdige, they control the woofer with authority.

[pos]

Nice build, and with build-in airflow too !!

Have you tried the new nc400?
I bought 4 of them for my 2 mains (and probably 2 more in the futur, but still only one powersupply per side), but I am stuck with the build of the case...
I would like to do something exactly like yours.
I whish I had your talent! congrats!

[gasfan]

Nice build, and with build-in airflow too !!

Have you tried the new nc400?
I bought 4 of them for my 2 mains (and probably 2 more in the futur, but still only one powersupply per side), but I am stuck with the build of the case...
I would like to do something exactly like yours.
I whish I had your talent! congrats!They are the ones I've been referring to. Midrange is apparently outstanding as is bottom end control. What is your take on the top end?

[pos]

Reading the datasheet tells the whole story: http://hypex.nl/index.php?option=com_weblinks&view=weblink&id=106&catid=42

I use them on my mids and high (TAD TL1201H and JBL 2450SL + Truextent Be diaphragms) and I can find no flaw in the way they sound!
Of particular interest with compression drivers is the very low residual noise (very high S/N ratio), and the fact that you can reduce the gain down to 13dB.
The lows (TAD TL1801) are currently handled by a MC2 MC1250, but switching to the nc400 is also an option I will try.

[gasfan]

In that case the NC400s will probably smoke the Mac.

[pos]

The MC1250 is not a Mac, it is a MC2 unit:
http://www.mc2-audio.co.uk/mc1250.html

not that easy to smoke I suppose :D

[Serum]

I couldn't afford these NC400's, perhaps in a later stage, but so far i'm focussing on getting the Behringer up the par with a new clock. The currntly used hypex units perform very, very good as they are. :) i'm starting to love them more and more. About the air-flow, i also added a 90x90fan with a tiny PCB to control the airflow.

https://lh4.googleusercontent.com/-mYMzH-7LOPU/UD_LiBMEB1I/AAAAAAAACro/QPH3DfSXJ6Q/s800/SDC13360.JPG

the 1200 watts SMPS takes some energy in idle, glad the fan is in place.

here (https://picasaweb.google.com/112333802006671383079/ActiveLinearSpeakerProject) is a link to the speakers themselves.

Currently listening to John Mayer, Born and Raised but is this studio mixer out of wack? or did he forgot he used the de-sser on the entire mix instead of the voice only? this is the most dull, flat sounding record ever. Great music, but this recording is poop? the guy recording must hate music? they are mixed on the set of barefoot mm27's, from my understanding. his acoustic recordings sound way, way, way better. Can't understand how someone can mess this up so bad.

[pos]

:eek: this is a true work of art!

Would you build such amp cases for others ? (metal heatsink + wood box to integrate in a speaker)

[Serum]

Thank for the kind words! I guess i could, never considered it though, give me some time to think about it. What is it you need? I could figure out something to help you out.

[gasfan]

Oh."" Yikes!""

[Serum]

Yikes, about the john mayer record? :)

[pos]

Thank for the kind words! I guess i could, never considered it though, give me some time to think about it. What is it you need? I could figure out something to help you out.

I'll send you a PM! :bouncy:

Concerning the crossover and the DCX, I saw one of your old messages and responded there:
http://www.audioheritage.org/vbulletin/showthread.php?22163-Anyone-else-using-active-X-O&p=337444&highlight=#post337444

[gasfan]

Yikes, about the john mayer record? :)No. It is what it is. I'm not much of a John Mayer fan. I meant my mistake about the amp. I haven't seen a lot of feed back on that one but I remember it being a stellar performer. Specs seem to back that up. There's lots of good stuff out there but I'm actually a vintage fan. I love tweaking and improving that old gear,(or having it tweaked). My technical knowledge is quite limited.

[Serum]

no, you haven't made an error with the amps. I choose hypex for the reason i wanted to integrate them into the enclosure. There is a lot of options out there for amps, and there is no holy grail in audio. I always loved the sound of an A/B amp. I have got an FM acoustics 800A as well. The sound quality is topnotch, but according to what i've read the amp itself isn't that special from a technical perspective.

Don't fear the variable you are unfamiliar with. Your ears tell you what you like the best. The most important factor IMO are the speakers themselves. if the rest is good, the small margins of 'better' cost a lot of money and can be between the ears.

[gasfan]

no, you haven't made an error with the amps. I choose hypex for the reason i wanted to integrate them into the enclosure. There is a lot of options out there for amps, and there is no holy grail in audio. I always loved the sound of an A/B amp. I have got an FM acoustics 800A as well. The sound quality is topnotch, but according to what i've read the amp itself isn't that special from a technical perspective.

Don't fear the variable you are unfamiliar with. Your ears tell you what you like the best. The most important factor IMO are the speakers themselves. if the rest is good, the small margins of 'better' cost a lot of money and can be between the ears.
Actually, I did. I mistakenly assumed your MC2 MC1200 was a Mcintosh. Pos corrected me. I agree with your position to a point. There are two main things an amp has to have or I'm not happy. The first is speed(slew rate, rise time), and secondly a high damping factor. Without them, there is no sense of reality.

[pos]

The MC1250 is mine :D

The MC2 has a very good damping factor (>1000), but these things tend to degrade with time and output oxydation and fatigue (relays, etc.).
That is why they recently changed the datasheet to >400, because that is the value they generally end up at after several years of use...
On the nc400 the damping factor is even much higher, around 13000, and furthermore it manages to maintain this value up to 16khz.
The slew rate of these class D amps is not that great though, as they are band limited above ~30khz to reject the switching frequency.

[Serum]

Yes, i couldn't agree more. Some amps simple don't push out the low frequencies like it should, while others lack in slew-rate. A bridged amplifier lowers his damping. But the biggest internal resistance available is the voicecoil itself. Shortening rings in the woofer also help to act as a 'brake' for the woofer. I had a Kenwood (trio) amp with sigma drive; it measured the EMF at the speakers terminal itself. (so two sets of wires went to the speaker, one for the music, and one feedback to the amp.) I heard good things about the older SA line of amps.

[hjames]

Shortening rings in the woofer also help to act as a 'brake' for the woofer.

:banana::banana:

Mama's little baby loves shortnin' shortnin',
Mama's little baby loves shortnin' rings ....

(just funnin' ya - no harm meant ... we ALL slip a letter here and there.)

[Serum]

Tiny typo and i get nailed.. Go ahead, blame the foreigner..

for those born after 1957;
http://www.youtube.com/watch?v=mqMf1P8BXMA

It seems that amps with a higher voltage also push out better lows. (from my experience) this would line up with faster woofers don't necessarily have a low MMS. (induction/amps/volts/eddy currents, if i'm correct)

[gasfan]

I guess I should ask. Is your volume control a Behringer product? If not, where should I look?

[Serum]

no, it's a kit, made by a Dutch guy; (there is a thorough walk-through manual on the site bellow)

http://www.linearaudio.nl/6chan-1.htm

It's available through Pilgham audio; http://www.pilghamaudio.com/index.php?page=dcx-active-upg

i think Ward, the owner, can also assemble the kit if needed

[gasfan]

Excellent. Thanks. What is the passive upgrade about?

[Serum]

That's an upgrade to the outputs only, no volume control. From my best understanding it's a passive component; the active one is capable of pushing out 5V, this passive one removes the opamps in the circuit.

[gasfan]

I'm not very technically knowledgeable at all. When I see "passive", I'm thinking not "active". Can you clarify?

[Serum]

That's exactly what it is; active uses active components, IC's to boost the level and to amplify, and the passive uses the standard DAC outputs. Active has got volume-control with IR remote control operation. What is it you need? volume control? in this case you need the active.

[gasfan]

That's exactly what it is; active uses active components, IC's to boost the level and to amplify, and the passive uses the standard DAC outputs. Active has got volume-control with IR remote control operation. What is it you need? volume control? in this case you need the active.
Okay. The Behringer is an active crossover to start with. Does the passive upgrade change this?

[Serum]

No, it still is an active crossover, even with the passive output-stage.