DD66000 crossover

[baldrick]

Could someone please explain the crossover used in DD66000?

Is it really correct that the crossover freq is 20khz between MF and UHF? And does this also mean that DD66000 without UHF will be abale to play up to 20khz? And if so... is there hardly any sound at all from the 045Be??

(I think this is he schematic for org crossover, found it in another thread.)

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=49083&stc=1&d=1292855219

[4313B]

The 476Be runs all the way out.
The 045Be was included because the system would never sell in Japan without it. It is up around 20 kHz so it can't eff up the pertinent system response. There is also the fact that the 045 aperture is much smaller than the 476 aperture. Let's all just say that it adds "air" and leave it at that eh? It does not perform like an 045 in a 1400 Array for example.

You might want to look at the DD65000 and DD67000 schematics I posted as well.
I also posted all the voltage drives showing exactly what the networks were doing.

A Crown IT HD can duplicate everything the passive network is doing, and more.
The result is an order of magnitude improvement in performance.
Note that if one goes full active, they absolutely should leave in the protection cap, along with the attenuation filter, otherwise the hiss from the c.d. will be insane.
Yeah, yeah, I know there will be some people who won't be able to hear a difference. Whatevski.

And there are some people who will just want a passive network regardless. I can accept that.

[ivica]

Could someone please explain the crossover used in DD66000?

Is it really correct that the crossover freq is 20khz between MF and UHF? And does this also mean that DD66000 without UHF will be abale to play up to 20khz? And if so... is there hardly any sound at all from the 045Be??

(I think this is he schematic for org crossover, found it in another thread.)

Hi baldrick,

May be You can start from here:
http://www.audioheritage.org/vbulletin/showthread.php?29853-h66000-h9900-h4365&p=299818&viewfull=1#post299818

and continue on the other , our forum member 4313B, (many thanks), has explained in details.

Regards
Ivica

[pos]

Baldrick, what transducers are you going to use?

There is an intermediate solution between full-fledged DSP active crossover and passive one: if you get the crossover region correct with passive components (complementarity, phase coherency and all, not an easy task but can be done with good transducers used well within their proper passband...) you can then use DSP EQ on the global stereo signal to get the response you want. Doing the raw CD compensation passively is also a good idea (and easy enough to do: one cap and one resistor...).

As 4313B hinted in the E2+sub thread, lowering the tuning frequency compared to the original cabinet would be a good idea if DSP EQ is to be used down low.

[baldrick]

Thanx a lot!

This gives me hope running DD66000 crossover (but without UHF) as a start for my upcoming "DIY Everest Project" :)

In the future I will absolutely consider running DSP instead but for now it would be great if it worked With Stock xo.

[baldrick]

Baldrick, what transducers are you going to use?


At first I'm going to use 1501AL and probably 2451BE, and DD66000 passive XO.


As 4313B hinted in the E2+sub thread, lowering the tuning frequency compared to the original cabinet would be a good idea if DSP EQ is to be used down low.

I'm thinking the same even if I use only partial DSP. Let's say I start with only one 2-channel Crown iTech running passive XO, then I still have the opportunity running some DSP EQ at the bottom. The bassport will be tested with a lower tuning than factory.

[pos]

Do you have 16 ohms truextent diaphragms?

[cooky1257]

Just be aware mixing active DSP on LF and passive MF/HF your DSP has latency-the signal through the DSP will be delayed slightly-it may not be an issue but if so one way round it is to pass MF/HF through flat.Kinda begs the question though why then not go full on DSP...

[baldrick]

Do you have 16 ohms truextent diaphragms?

I have not bought truextent for this setup yet... is 476Be 16 ohm?


Just be aware mixing active DSP on LF and passive MF/HF your DSP has latency-the signal through the DSP will be delayed slightly-it may not be an issue but if so one way round it is to pass MF/HF through flat.Kinda begs the question though why then not go full on DSP...

As long as both MF and LP is used by the same DSP i don't think latency could be an issue?

The reason for not full DSP right away is simple.... the total cost :) But again.. nothint is settled yet so maybe that will be the outcome but for now the plan is passive xo.

[ivica]

At first I'm going to use 1501AL and probably 2451BE, and DD66000 passive XO.



I'm thinking the same even if I use only partial DSP. Let's say I start with only one 2-channel Crown iTech running passive XO, then I still have the opportunity running some DSP EQ at the bottom. The bassport will be tested with a lower tuning than factory.

Hi baldrick,

I think that using truextent over 10~12kHz in 2451 motor would not satisfy your expectations (not to use UHF driver), but if You can get 476Be diaphragm that would be expectable better.

Regards
ivica

[pos]

I have not bought truextent for this setup yet... is 476Be 16 ohm?
It is: http://www.audioheritage.org/vbulletin/showthread.php?33761-476Be

That said, if you look at the Radian+Be vs 476Be Guido made, even the 16 ohms truextent does not give the same impedance curve as the 476Be:
http://www.behringer-electric.de/files/news/Radian_Truextent/Vergleichstest%20951PbTrExt4016%20vs%20476Be.pdf

Granted this is a different core, and the 2451 core might give different results, but in any case you can expect the Fs to be lower with the truextent diaphragm (softer surround).
The 476 core also has special tricks to avoid the impedance rise up high, but this can be EQed without penalty.

Anyway, I have no idea how these impedance differences will impact the passive crossover, but you would better simulate this before you start.


I think that using truextent over 10~12kHz in 2451 motor would not satisfy your expectations (not to use UHF driver)
Personally I like the Truextent UHF just right :)

[4313B]

The reason for not full DSP right away is simple.... the total cost :) But again.. nothint is settled yet so maybe that will be the outcome but for now the plan is passive xo.Understood. :)

[cooky1257]

2452/TruextBe on H9800 horn @4m listening position. Good up to 15khz imho.


https://farm6.staticflickr.com/5608/15355929867_dca511d931_z.jpg

[audiomagnate]

The general consensus seems to be they need to be "re-voiced" for western ears. A three way electronic crossover, a parametric EQ and some port extensions (or plugs) will allow you to make them sound however you like.

[Mr. Widget]

The general consensus seems to be they need to be "re-voiced" for western ears. A three way electronic crossover, a parametric EQ and some port extensions (or plugs) will allow you to make them sound however you like.Are you suggesting the general consensus is that factory DD66000s need modification for western ears?


Widget

[4313B]

The general consensus seems to be they need to be "re-voiced" for western ears. A three way electronic crossover, a parametric EQ and some port extensions (or plugs) will allow you to make them sound however you like.I don't think there are very many people who actually care.

[BMWCCA]

I'd love to find out.

But then I'm in a small room anyway so they'd probably be fine as they are. :dont-know:

[Mr. Widget]

I don't think there are very many people who actually care.Not sure if they care, but there certainly are a lot of people with opinions. :)

Having lived with them in my home for the last 2 and half years I am pretty familiar with them and have my own opinions. ;)


Widget

[4313B]

Not sure if they care, but there certainly are a lot of people with opinions. :)

Having lived with them in my home for the last 2 and half years I am pretty familiar with them and have my own opinions. ;)I meant actual owners of the systems. My understanding is that there were a small number world wide who wanted to upgrade the low frequency transducers but the last I heard Harman wasn't all that interested in allowing it to happen.

[baldrick]

I guess it will be easier for us with "replicas" of Everest doing experiment than for owners of original speakers. At least I know I feel better "messing around" with a replica instead of a $60.000 speaker :)

My current speakers are 20-22k +-3db and it would be great haveing almost the same from Everst but to achieve this I will need to lower the tuning of the port quite a bit and also ad EQ, but I will be tried!

It would be fantastic finding a pair of obtainable 476Be but in the meantime the 2451BE will have to do.

[4313B]

I guess it will be easier for us with "replicas" of Everest doing experiment than for owners of original speakers. At least I know I feel better "messing around" with a replica instead of a $60.000 speaker :):) I can understand that.

My current speakers are 20-22k +-3db and it would be great haveing almost the same from Everst but to achieve this I will need to lower the tuning of the port quite a bit and also ad EQ, but I will be tried!Not a whole lot different than what JBL Professional did with the M2 (2216Nd) versus JBL Consumer and the S4700 (2216Nd). ;)

Did you read my discussion on the M2 versus the S4700 and where that 2 dB drop in efficiency with the M2 went? In short, a -8 dB high pass shelf with a Q of 5.5 starting at 135 Hz coupled with the +6 dB baffle step results in the 2 dB drop in efficiency. There is also the + 4.7 dB boost at 21.5 Hz with a Q of 1.77 to fill in the bottom octave. I've personally found no reason at all to tune the 1501AL-2 that low in my situation. I am perfectly happy with them tuned around 28 Hz, which is roughly only 2 to 4 Hz lower than the stock Everest II. I do have a +4.5 dB boost centered at that 28 Hz frequency and I really like the result. The addition of subs would be ludicrous in my environment which is why I'm not crying about not being able to get a pair of the low Fs 1501AL-1's for potential use as subs.

[baldrick]

Santa came early :)

63449

[1audiohack]

And you must have been very very good this year!

Barry.

[marcstpierre]

if you cut at 12db down beginning at 20khz it will only bring efficiency 12db less 1 octave lower, so -12db at 10khz to join the efficiency of the rest, so it be flat.:)oups i think i respond to the first post ,im new here ,i have to make habit that first is last.