Film-Tech Forum ARCHIVE: Dolby's New Server..DSS200, supersized racks required!!

This is topic Dolby's New Server..DSS200, supersized racks required!! in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Tony Bandiera Jr (Member # 2365) on 07-11-2009, 11:38 PM:

Working on a private screening room install right now. Had to add D-Cinema to the room, I was actually looking forward to installing the Dolby Show Player/Server..until I went to pick up the equipment.

What used to be nicely done in two separate chassis, the newest version of the Dolby system is ONE 3RU high, 70(!) pound, unit that is 27 inches DEEP!! (Oh, and you need to add another 2-3 inches for cables to clear.)

Sigh. A huge pain in the ass when the existing rack (which due to location cannot be replaced without a huge expenditure of time and labor) is only 17" deep. We are having to build custom rack ear extenders to limit the encroachment in the back and front of the rack. If the end result isn't too hacked, I'll get a pic to share here in this thread, if the mods don't mind.

Be forewarned if anyone is planning on a installing a new Dolby Server you will either need a DEEP true server rack, or have a lot of room behind your existing rack and be prepared to lose the back door.

I have also been told that Dell is building them for Dolby now....yikes. (Not sure how true that is though.)

I can understand the economy in making the unit one chassis instead of two, BUT why rush it? They really needed to either make the unit taller instead of deeper or wait till the technology will allow a standard depth chassis.

Were the older models that bad, or did Dolby just make a dumb design move here?

Posted by Adam Martin (Member # 641) on 07-12-2009, 01:13 AM:

24+ inches deep is not uncommon for a server. We work with computers now ... get used to it!

Posted by Steve Guttag (Member # 268) on 07-12-2009, 07:55 AM:

17" deep rack? That is shallow by any standards...20" was the shallowest I've ever worked with on floor standing racks.

We moved to 25" for film based sound racks long ago. For video we quickly went to 27" and are now moving to 31" deep racks with wider sides. With video, one has to plan out the bulk of the cables themselves as well as their minimum turn radius (also...even Cat5/6 has to take gradual turns (and only have very lite binding, like with velcro) and this takes up space.

I agree, in existing installations (upgrades), increasing the depth can be more of an adventure. Since we blow filtered air into our racks, we don't want to loose the rear doors.

Remember too, Tony...many folks are putting the servers in the base of the projectors, which for most, is virtually hollow and upwards of 4-feet deep so a 27" deep server fits with plenty of room.

Steve

Posted by Sam D. Chavez (Member # 1841) on 07-12-2009, 11:10 AM:

Isn't it silly that we are putting the Dolby servers in the projector base and then need to use 50 Ft. HD SDI cables to avoid some yet unsolved issue with Standing Waves or attenuation issue between the server and projector when we use appropriate length cable.

Posted by Pete Naples (Member # 761) on 07-12-2009, 11:57 AM:

We are?

Can't say I've encountered that one Sam.

Posted by Steve Guttag (Member # 268) on 07-12-2009, 12:49 PM:

Honestly...we are not using 50' cables...the only way you are going to have a problem with shorter lines is if Dolby and/or the projector manufacturers are not complying with SMPTE 292...there is no minimum length. If there was, broadcast facilities would be failing all over the place.

I've seen no valid reason for the 50-foot theory. Furthermore, one would have to define WHICH cable needs to be 50-feet. That is, all HDSDI tested cables have different attenuation cap. specs...we use Belden 1694A/1695A...I've seen some use 1505 too and it seemed to work just fine.

Steve

Posted by Tony Bandiera Jr (Member # 2365) on 07-12-2009, 01:23 PM:

Steve, it is possible the rack is 20" deep, I'll have to measure it again when I go back tomorrow. It is the same room the QSC amps for sale are coming from.

Adam, I'm old-school film and actually despise D-Cinema on many levels..thankfully I will be retired (or dead) before it's the only game in town. [Big Grin]

I am involved in this install as a favor to the client.

Now I didn't have any hands-on with the old show player and server, but if I remember the spec sheets right it wasn't that much deeper than a CP-650 (Which fits quite nicely in our rack BTW.)

EDIT: Per the spec sheets, the Player DSP100 is 17.7" deep, and the DSS100 is 23" deep. Dolby spec sheet

I just think it is a sign of someone's lack of perception of reality that the vast majority of installs are very likely to use the existing standard audio racks which aren't deep enough to accommodate a 30" deep unit.

Of course on a new install a 30" deep rack would be specified and not an issue..other than the extra expense. [Roll Eyes]

And I do find the 50' cable thing odd....I always thought that standing waves were an issue only with longer cables...

Posted by Pete Naples (Member # 761) on 07-12-2009, 05:19 PM:

Tony, on teh vast majorit of installs that I see/do, the server is carried in the racking space in the projector pedestal, in which one could comfortably accomodate the server, sound system, automation interface, 3D controller, scaler and a few homeless persons [Big Grin]

On one job we put the server in the sound rack, which was already big enough to hold it, one other place the server went in a stand alone rack as the sound rack didn't have enough height, never mind depth. In fact that booth will shortly have two servers in the dedicated server rack.

Posted by Tony Bandiera Jr (Member # 2365) on 07-12-2009, 10:18 PM:

Pete, the vast majority of my clients are home screening rooms now. I haven't serviced a regular cinema in years. [Big Grin]

Normally, in the home screening rooms, we use smaller NEC or Christie projectors (the room I'm working on now is using NEC) and it is almost always on a video lift. So we don't have the pedestal base on the projector. (I'm not sure our Christies are D-Cinema capable anyways, and I so far haven't run into any Barcos or *gag* Sony.)

Also most of the home screening room booths are tight on space to begin with. That is why this new server is gonna cause a lot of headaches in my neck of the woods.

Posted by Sam D. Chavez (Member # 1841) on 07-12-2009, 10:32 PM:

The cable length issue is well known to Dolby techs and seems to involve Dolby/Barco installations to my own knowledge. I too was skeptical, but I had the problem and so did Jack Cashin.

Mine involved a CP2000 with Canare 706 cables made by Lonny Jennings and Jack's was with custom cables and a DP100.

Dolby's output level is said to be higher than some others servers, but who knows the real reason, I'm new here.

Apparently things do go bump in the night in D-Cinema, this is just one of them.

Mine showed up as a loss of picture and a black screen every so often. Tried everything else and finally changed out the cables and problem gone.

BTW I've been selling nothing but 32 and 36 inch deep racks for some time now.

Posted by Steve Guttag (Member # 268) on 07-13-2009, 01:35 AM:

Hmmmm interesting on the cables. Having worked with SDI HDSDI for quite some time now...I've never encountered an issue. If Dolby's server is out of spec, that is the true problem...50-feet of cable is a band-aid approach and certainly a waste of copper. Certainly, they can put the effects of the longer cable into their output (capacitance and attenuation...about 2-3dB for 1.5GHz in that length). Could you imagine how much cable would be in a typical broadcast installation if everything needed a 50-foot cable?

Oddly enough, on the Barco DP50 (1.3K machines) with the ACSAR 1, anything OVER 15-feet was risky!

As to racks...I never much cared for 36" racks since one almost has to stand IN the rack to wire most things. On the upside...you can really use the rear half for things that don't have to show providing you leave yourself a way to get to the front stuff.

Steve

Posted by Phil Ranucci (Member # 3820) on 07-13-2009, 03:22 AM:

While on the topic of racks, any RF problems with putting the server in the pedestal of a Barco DP2000?

Posted by Mark Gulbrandsen (Member # 72) on 07-13-2009, 07:58 AM:

quote: Tony Bandiera Jr
I have also been told that Dell is building them for Dolby now....yikes. (Not sure how true that is though.)

Actually that may be a very good thing for Dolby... they can lay off some more people! DTS had been doing the same with their server till the project was shut down and DTS was actually letting Dell do the on site service and repairs to the servers which was very convenient... but is todays Dolby actually this snmart???

quote: Steve Guttag
As to racks...I never much cared for 36" racks since one almost has to stand IN the rack to wire most things.

Steve... you need to eat less cheese so you can fit inside the rack... [Eek!]

Apparently none of you are using true server racks where the sides lift off. No need to stand inside the rack to do the wiring... and you can also mount the server on rack slides for easy removal and servicing, you'll find things set up this way in any IT facility worth it's spit. The IT type racks are made by many companies including Mid-Atlantic and they are more expensive. I personally prefer to put the server in the projector base... Unfortunately the larger projectors don't generally have the amount of space one needs.

quote: Sam D. Chavez
Isn't it silly that we are putting the Dolby servers in the projector base and then need to use 50 Ft. HD SDI cables to avoid some yet unsolved issue with Standing Waves or attenuation issue between the server and projector when we use appropriate length cable.

Sam is correct and this also affects some Christie models as well... no doubt actual units that heir Guttag has installed... CP-2000's and ZX's. With the Christies the funny thing is that the problem may not appear for quite some time or it may appear right away... go figure... The problem lies both in the projector interface board AND in some servers having higher output levels. This causes a level mis-match between the two and (according to Christie techs) sometimes overloads the input circuit on the projector interface board. Christie has available convenient but pricy in line high frequenncy (3-4ghz!) attenuators that sometimes solve the problem... Which can be anywhere from a predominately colored screen image to bright white with no image present or a flash of white at the first startup of the first show of the day. A reboot of the system usually clears the colored image the problem. Many times this goes un-noticed or unreported because it's no more than a flash. I've seen a number of locations still exhibit this problem even after the cables were made 50' long and or the attenuators installed. Also, check the SMPTE error count in the TI engine... you'll generally find alot of errors. If one or the other add ons don't fix the problem then the projector interface board has to be replaced. Christie has generated a service bulliten regarding this with part numbers for the attenuators. They will only replace the interface board as a last resport but the new board apparently does not have this problem. I still feel they are pushing the linits for HDSDI in D-Cinema and had they used Triax for the HDSDI lines the standing wave problem probably wouldn't exist plus you could locate the server up to two blocks away from the projector!! Triax connectors are a bit pricy but the BNC variety are not to out of line. Also, one would think that increasing the length of the cables would increase the chance for standing waves and ro internal reflections. It may also increase the mount if induced "digital jitter" present on these lines.
BTW: This is why Dolby supplies 50 foot cables in the CAT 899!

quote: Phil Ranucci
While on the topic of racks, any RF problems with putting the server in the pedestal of a Barco DP2000?

I put a Dolby system in the base of the DP-100 once and it worked just fine... wouldn't do it again though and the BARCO racks are non-standard european type... If you need extra goofy rack hardware call BARCO for it.
Mark

Posted by Scott Norwood (Member # 30) on 07-13-2009, 08:22 AM:

This is the first that I have heard of the 50-foot thing. Does it apply to HD video as well, or just D-cinema applications?

At least with video, HD-SDI is very forgiving, and I've not seen it fail on short runs (under 20' or so), even with bargain-bin cable.

(I have not yet had occasion to work with the current generation of D-cinema hardware, but I do deal with a fair amount of HD and SD video.)

Posted by Sam D. Chavez (Member # 1841) on 07-13-2009, 10:43 AM:

Mark brought up the TI error count and this was the evidence the solution worked as the count went way down to nothing after the cables were changed.

Posted by Steve Guttag (Member # 268) on 07-13-2009, 01:50 PM:

The Error count is definitely something I'll be checking on existing installations. I guess more cable for me to sell...we stock the stuff on 1000' rolls so there is no big deal there (in red and green). Mark, whereas we make all of the cables in the Cat 899 kits, and can control the quality on them, we custom make them on-site (or in the shop to the system) to the lengths needed...so far, zero failures.

There is nothing really being pushed by the DCinema version of HDSDI...in fact it is still 1.5G stuff. Nothing too fancy there.

It sounds mostly like sloppy compliance with SMPTE 292 on either projector or servers.

Scott...I can assure you, in the broadcast grade video world...there is no 50-foot minimums...I've worked with 18" up to 100s of feet and even done repeaters to go beyond 300-feet.

Mark...we do use removable side-panel racks when we go to gangables but I don't like wire things from the side. We always rear support extra deep or heavy items too (like MXa amps from QSC). Nothing new there either.

Somewhere on this site are photos of some of the racks we have done...there is always a healthy amount of room in the rear to create cable chases, power strips, sufficient bend radius...I just don't go overboard on the depth...heck we were using 25" deep racks when others were still on the 20" deep varieties. I do, however, dislike working on 36" racks unless the bulk of the equipment is indeed over 20" deep.

Steve

Posted by Mark Gulbrandsen (Member # 72) on 07-13-2009, 07:04 PM:

quote: Steve Guttag
Mark, whereas we make all of the cables in the Cat 899 kits, and can control the quality on them, we custom make them on-site (or in the shop to the system) to the lengths needed...so far, zero failures.

I have been doing exactly the same since installation #2. We used CAT 899s on the first two just to gauge what was needed ina typical install. I'd reccomend all newbies do the same the first time round. As for QC'ing cables there's nothing difficult that you really need to quality control there... especially when one has put on over 10K BNCs. The mian thing is the cables should be exactly the same length. I like Sam prefer the Mogami Coax probably a thousand fold over Belden.

quote: Steve Guttag
Mark...we do use removable side-panel racks when we go to gangables but I don't like wire things from the side.

Wiring from the side is far better then standing inside anbd you can share the cheese with others working in the shop! Servers generally go in on rack slides with a cable management arm in the rear of the unit. All the cabling gets secured to the management arm so when you slide the server out all the cabling comes out with the unit being slid out. Works really well. The first place I used rack slides was back in broadcast where much of the master control equipment went in on slides... alot of it required frequent servicing or was super difficult to remove fomr the rack by yourself.

Mark

Posted by Brad Miller (Member # 2) on 07-13-2009, 08:58 PM:

We used 36" deep racks for City Center and I can say that it is definitely a pain to "live inside the rack" while wiring. I, like my platter-loving friend Steve, greatly prefer for the rack to be easily accessible from the rear without having to "climb into" it. That being said we did front and rear mount equipment and it was so close there is barely enough room to put your hand in between the backs of the equipment (and just barely enough room for the cabling to curve as needed). We even had to mount various converter boxes and such to the sides of the rack to get it all in there, but unless you pull the side panels off...you will never see all of that.

Moral of the story...never again!
[Eek!]

Posted by Steve Guttag (Member # 268) on 07-13-2009, 09:59 PM:

Sam actually said Canare, not Mogomi...both of which I do indeed like. However, for HDSDI...Belden 1694A is very much the standard by which others are judged.

I tend to go to Mogomi for uber-flexible cables...their mic cable and snakes are tough to beat...in fact...they are generally all very good.

We haven't used Canare much other than their star-quad cables...however we tend to use Belden now.

Steve

Posted by Mark Gulbrandsen (Member # 72) on 07-14-2009, 07:57 AM:

Steve,
My bad... I meant to say Canare... I also have their crimp tool.

Brad,

What did you mount in there that was so deep? The Doremis are not all that deep... or why not just use two shallower racks? Was it a cost factor?

Mark

Posted by Tony Bandiera Jr (Member # 2365) on 07-17-2009, 11:51 PM:

An update: On the insatll I'm doing, I have placed the server in the rack, it is (for now) just sitting on top of the stack of DCA amps. It sticks out the front of the rack by a foot.

I am waiting for my "boss" to return the mounting rail slides that he had modified to better fit the rack. (His idea, not mine. I thought the full-length rails would fit just right....)

It isn't quite the horror show I thought it would be, but I still don't like it.

Once it's fully mounted I'll see about taking some pics.

Posted by Louis Bornwasser (Member # 3063) on 07-20-2009, 02:03 PM:

Sounds like the box channels we made to install dts into Smart racks. Darn things stuck out almost 5 inches! Louis

Posted by Tony Bandiera Jr (Member # 2365) on 07-20-2009, 04:30 PM:

Louis, yep, 'cept the box channels in this case will be 12" long! [Big Grin]