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Author Topic: JSD 60D crossover Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 01-17-2015 05:05 AM                     I'm looking for some feedback on the crossover option in a JSD-60D. Does it work well? I have used Behringer's in the past: they're ok for home use, not for professional use - not reliable. What would a good budget alternative be, without going for a DCM? Harold's opinion also very welcome!  |  IP: Logged Stephan Shelley Jedi Master Film Handler Posts: 854 From: castro valley, CA, usa Registered: Nov 2014 posted 01-17-2015 02:16 PM                     I was involved in s retrofit of a theatre that had been using the crossover option in a CP-45. The JSD-60D worked out well. It has been over a year and no problems. I have had some issues with the QSC crossover monitor. One was issues with the surround input from a 650. Even though I programed it it did not want to enable the special input from the 650 surrounds. After finally getting it to work correctly a few months after the install it disabled itself. Also one nit to pick is that since they started making there own speakers the library of configurations only includes there own. A little off topic but the JSD-60D has a drive-in mode too. Another option is the USL moniter crossover.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 01-17-2015 06:34 PM                     I just can't say anything at all bad about the JSD-60 or the JSD-100. I have installed hundreds of them and not a single failure of one unit. Some JSD-100 are nearing five years old now. Mark  |  IP: Logged Harold Hallikainen Jedi Master Film Handler Posts: 906 From: Denver, CO, USA Registered: Aug 2009 posted 01-19-2015 11:37 AM                        Thanks for the comments! There are, of course, several places in the signal chain the crossovers can go. As mentioned, the JSD-60 supports biamp of three screen channels. The manual at http://ftp.uslinc.com/?dir=ftp/Products/JSD-60/ provides a fairly extensive description. The GUI is also there for you to try. There's also a beta version available that adds support for AES/EBU outputs and BLU link outputs. The USL monitors with crossovers has already been mentioned. There's now also a separate crossover that uses the same cards as the monitors. See the XTM-300A and XTM-300D at http://ftp.uslinc.com/?dir=ftp/Products . Where to place crossovers is an interesting area for discussion. Some speakers include crossovers that are matched to the speakers, but these tend to be inefficient and may be overly simplified since power components are used. Next, many amplifiers include DSP crossovers. Crossovers can be moved back up the signal chain to between the processor and amplifiers, or back into the processor itself. Since the processor already has one or more DSPs, adding crossovers there is not overly complex or costly. It does add hardware in most cases. With the BLU link (or similar networked audio outputs), no additional hardware is needed. Placing the crossovers in the processor is probably the lowest cost method since no additional devices or DSP-based amplifiers are required. This also keeps all the audio settings in one device simplifying setup and (heaven forbid) equipment swap outs. THANKS! Harold  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 01-19-2015 01:42 PM                     You're not trying Mark...I can say something bad about most anything...including stuff I like! I'm not a fan of crossovers in the processor but understand why some may like the idea. In our systems, that adds wiring to the monitor and often limits one a bit on the type of crossover you are going to use. For example, the JSD60 sports a L-R 24dB/Oct crossover. Is that what you need? Perhaps and it is a good type of crossover if you only have a choice of one. We are often tri or even quad amping speakers now...again a cinema processor is going to fall a little short in that department, most of the time. Putting the crossovers in the monitor makes a certain amount of sense as wiring is not complicated then. Certainly QSC has done well with the DCM line of monitors and THX also took this approach. A potential downfall in this is I've found most booth monitors to take a "cheap" approach to construction...it can be risky to run your signal through a cheap monitor. I've seen numerous audio drops due to poorly made booth monitors being the "Tie" point between the cinema processor and the amplifier. We always wire our systems such that the monitor can be removed without interrupting signal flow...unless it is a monitor/crossover or a cinema processor/monitor/crossover. The vast majority of our systems use separate crossovers (now DSP based) and if we do that, we normally leave the cinema processor EQ flat as almost all use Graphic EQs rather than parametrics. One can tune MUCH better with parametric EQs. The notion of the amplifer having the DSP with the crossover is an interesting one though I've found that beyond the crossover, they are often too limited and awkwardly configured. Plus...when the amplifier fails it may not be a simple task to swap it out as the DSP stuff died with the amp. If you didn't put the system in, there may not be a good back up either. Another thought is to use self-powered speakers and let the speaker manufacturer handle the amplifier and crossover. That would make tuning go pretty fast since it should be "flat" out of the box. Wiring would all be with low-level small cables and one merely need have outlets for each speaker.  |  IP: Logged Carsten Kurz Film God Posts: 4340 From: Cologne, NRW, Germany Registered: Aug 2009 posted 01-19-2015 02:22 PM                     I know a lot of cinemas using the cheap Behringer DCX2496. In a fixed installation and properly set up, they are not that bad. Good thing is, they have both analog and AES/EBU inputs. You can network them using RS232/RS422. If your cinema processor fails, you can actually bypass it and use your bunch of DCX2496 as your CP as long as your real box is under repair. You can actually control all centrally from a laptop, level, have analog Non-Sync options, etc. Having a fail-safe option is sometimes more important than the highest level of audio fidelity, especially with Bi- or TriAmped systems where you can not simply throw in any other device. These Behringers have been built for mobile/PA use. They may not be the most reliable under heavy use in that environment, but under stable cinema condition, I would consider them a decent choice. Plus, they come at a price where you can easily stock a spare. - Carsten  |  IP: Logged Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 01-19-2015 02:37 PM                     Thanks all for your feedback. In my case, the cinema owner already has a JSD60 and it would make sense just to purchase the crossover card. It's a budget installation, but they're looking to upgrade the speakers. I have some experience with DCX2496. They used to work fine in a home environment. An acquaintance of mine has had to replace his three times in his cinema, and the faulty ones were coming back from Behringer with the same intermittent fault. Eventually he had to open them and fix the poor connections by himself. I also heard of a big chain which went for Behringers and are now replacing at least one unit every month. Behringer used to feature an advanced replacement - which was great for a cinema - but they discontinued it. To have a DCX repaired it took more than a month if memory serves. Unacceptable for a cinema. Sorry, I may consider those for my Home Theatre (the crossover actually works very well in terms of sonic performances) but I can't recommend a DCX outside the enthusiastic realm.  |  IP: Logged David Buckley Jedi Master Film Handler Posts: 525 From: Oxford, N. Canterbury, New Zealand Registered: Aug 2004 posted 01-19-2015 02:56 PM                        I too have had unfortunate experiences with the berry DCX2496. Which annoys me as loads of people use them without problem! Thus I wouldn't recommend them for high availability use unless you have a spare and switching so you can flip to it instantly. However, even if you buy two (or three, or four), you're still saving money compared to a quality and feature equivalent DSP crossover. Having said that, its functionally not a great match to the requirements of a cinema looking to do 5.1.  |  IP: Logged Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 01-19-2015 02:58 PM                     I didn't realise a Beringher was so cheap? There are DSP's everywhere these days, are DCX still massively cheaper than competition?  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 01-19-2015 04:11 PM                     Carsten, Speaking of failsafes...I had a site where the amplifier failed for Center channel...faster than they could swap an amp, I remoted into the DSP crossover (RANE HAL based system) and fed Center out of Left/Right. I've done the reverse too...if the Left/Right amp filed...monoed up everything and fed out of center. In fact, you could set up presets so that they would go even faster...but thankfully, this is not a common occurrence. Personally, I don't think enough consideration is given to the whole crossover and how the speakers are tuned, as a general statement. I've also found that most "factory" specs on tunings to be not real-world. The surprising one is that the delay for time-alignment is often worse than no delay at all. Another thing is all DSP isn't created equal as far as sound quality . High bit/sample rate is no guarantee of better sound quality either. I've definitely heard 16/48 out perform 24/96 though 24/96 should win every time. It is why I do get fussy on the stuff I use that has a direct affect on sound quality.  |  IP: Logged Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 01-19-2015 04:19 PM                     quote: Steve Guttag I've also found that most "factory" specs on tunings to be not real-world Me too. The point is that most installations are just 'factory', single mike in the Dolby position, X-curve and go to the next auditorium. quote: Steve Guttag Another thing is all DSP isn't created equal as far as sound quality That is exactly what I was asking in the first place. I'm sure the JSD60 can split the band in two or three, but does it do that right? Does it sound right? Does it do a decent job or would an external crossover be much better in term of sound quality?  |  IP: Logged Carsten Kurz Film God Posts: 4340 From: Cologne, NRW, Germany Registered: Aug 2009 posted 01-19-2015 04:31 PM                     quote: Marco Giustini They used to work fine in a home environment. An acquaintance of mine has had to replace his three times in his cinema, and the faulty ones were coming back from Behringer with the same intermittent fault. I had that happen as well. As a matter of fact, once I received a Behringer with a handwritten failure description in the box as 'new'. And it still had that issue ;-) But I think these boxes never really made it to Behringer, but only to your suppliers repair department and back ;-) The Behringer DCX2496 can be bought for as little as 300€ here, or 250 without VAT. I think the closest competition with digital inputs go for twice ot three times the price. That add's up for all your screen channels. They are quite flexible with their analog and digital inputs. I have never heard of any unusual failure rates around here. But that device is pretty old now and still selling very good. One reason for Behringer to keep it available. There may have been very different batches quality wise over the years, as Behringer had them manufactured in China. And yes, I would never install them without keeping spare at hand. - Carsten  |  IP: Logged David Buckley Jedi Master Film Handler Posts: 525 From: Oxford, N. Canterbury, New Zealand Registered: Aug 2004 posted 01-19-2015 05:22 PM                        quote: Steve Guttag Personally, I don't think enough consideration is given to the whole crossover and how the speakers are tuned, as a general statement. I believe that to be a true statement, and with far wider applicability to cinema. The discussion about the Berry DCX is all very well, but for a cinema you need a lot of them (assuming screen channels are identical) with a bunch of wiring. The Rane HAL system mentioned is one of the "drag n drop" DSP solutions that are just so much better than everything that went before them, others being Soundweb (where this paradigm started), Symnet, and there's more that I cant remember right now. These really come into their own where there are lots of inputs or outputs or both, and now that digital audio networking is commonplace, these solutions provide an especially great solution. The only problem is that they are relatively expensive. Perhaps more annoyingly, they expensive for what they are.  |  IP: Logged Carsten Kurz Film God Posts: 4340 From: Cologne, NRW, Germany Registered: Aug 2009 posted 01-19-2015 05:56 PM                     Would be less annoying if you'd use them to replace both crossover AND cinema processor. After all, a current digital CP is nothing else than a HAL, Soundweb, etc., with a single parametric 'cinema processor' preset. On the other side, if the CP has digital crossover functionality, why should that be inferior to a crossover implementation in a configurable Audio DSP box? Okay, most CPs do not have enough I/O to implement Tri- oder Quad-Amping. - Carsten  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 01-20-2015 06:37 AM                     I think the design emphasis is much different. No, there is no reason why the CP can't have a good crossover design. QSC makes their DCP line and the crossover in there is at least as good (actually better) than what is in their DCM and most any other cinema processor based crossover. It is still limited as compared to one of the various DSP boxes. While it is true that if all you wanted from the DSP is a good crossover, the DSP solutions are a bit pricey...but when you factor in tuning as well as possible other channel routing, mixing, leveling...they become more economical. Also, one has to factor in cost/performance. If they do the job better and yield a consistently better result, then part of what you are paying for is quality. Why does a QSC SC-424 cost so much more than some cheap Peavey speaker? Well one does a MUCH better job than the other. I claim that crossover and EQ have a great affect on the outcome of the sound. As such, paying more for a better piece is a reasonable expense. For us, the RANE HAL3S offers quite a bit of bang for the buck (and rackspace). Out of the box, it is a 2x6 DSP (stereo 3-way) but adding two RAD-16s to it it becomes a 6x10 DSP so you can effectively set up an entire 5.1 system. One thing most DSP based systems now get you are the ability to remotely locate your inputs/outputs where needed. This can also facility lowering the costs of big heavy copper runs. I have discussed the concept of using a HAL1x system (with Rane) as the cinema processor as well as DSP. Cost wise, it is on par with a DCP300 system with similar ins/outs. What you miss out on generic DSP systems, typically, are "pro-logic" decode blocks. Since DCinema felt the need to issue "2.0" DCPs...including the home-made stuff...one really does need a "proper" pro-logic decoder in there somewhere. A simple L+R/L-R system really isn't sufficient. That is really a "better than nothing" solution. I know some that have used Basis as the Cinema processor but again without Pro-Logic capability. The JSD60 has the pro logic decoder...BUT it, at the present time, doesn't work with the 1/2 input! I've considered using a passive splitter to send 1/2 to both the 1/2 input and the S/PDIF input (impedance matched) on this and other processors to get the pro-logic decoder. QSC promises to activate their decoder for the Digital inputs on the "next" release (they only have it on the other inputs).  |  IP: Logged

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