Cinema Product Reviews

BACP DSTR-20 Dolby Digital penthouse reader
Manufacturer: USL
Grade:  A
Reviewed August 2009 by Joe Redifer

So you are still showing film at your theater and want to add some Dolby Digital sound to improve your presentation, but you can't decide whether to get the Dolby Cat. 702 penthouse reader or the BACP DSTR-20 penthouse reader from USL. The Dolby-made reader is well-known for it's excellent performance and great reliability and it really does deliver. But can this cheaper alternative be as trusted and as reliable as a genuine Dolby product?

The Dolby Cat 702 reader is sleek and beautiful. It looks like something from the future and it probably is. If it just had a spoiler and a racing stripe it'd be perfect. However the BACP DSTR-20 has a more boxy, Scion-like appearance and might not impress random booth-goers as much as the Cat 702. However, recent federally-funded scientific tests did reveal that a significant percentage of booth-wanderers were quite taken by the two-tone appearance of the DSTR-20 and preferred its looks over the Cat 702, so it's a toss up. Both units are very rugged and the DSTR-20 feels very solid and tough. The weighty flywheel gives the impression of immense power. It bolts to the projector with a commanding presence, just as long as that projector is a Christie, Century, Simplex, Cinemeccanica or even a crappy Ballantyne. If you have a Norelco or a Kinoton you must get an adapter plate and that makes its presence a bit less commanding and you a bit less of a man. What is interesting is that USL does not offer the plates, you must get them from Dolby. Just pretend you are ordering them for a future Cat 702 so Dolby isn't sad.

I've been using Dolby Digital readers for as long as you or anyone else can remember. I started with the glorious but not sexy Cat 699 and stepped up to a Cat 700. I've used Cat 701's at film festivals to play artsy-fartsy stuff and I have also used over 3 different styles of basement readers on various brands of projectors. Error readings ranging from 4's to 6's were common in just about all of these readers. Seeing any reading go below 4 was extremely rare, though it occasionally happened. The Dolby Cat 702 averages a reading of 2's and 3's for most prints, lower for many. The DSTR-20 promises the same thrilling performance as the Cat 702 and it definitely delivers if not exceeds in some cases. Seeing 0's and 1's are not uncommon even on big release prints that were printed at 10 billion frames per second. I spend hours upon hours just watching the error rate in amazement, especially since that is more entertaining than most movies these days. We have our current average error rate advertised on our marquee for each movie. Granted, there are rare prints that come through now and again which will hold a steady 6 and a half throughout. But for Dolby Digital, you can't get any better here. The same prints that run at steady 7's on a friend's Cat 700 reader and Cinemeccanica basement readers run at 3 and below on my DSTR-20's. I always gloat when I am around him since it helps make me feel better about myself as a person and I know he appreciates it... who wouldn't?

Both the Cat 702 and BACP DSTR-20 have long-life LEDs that should last for at least 5 years. That means if they had installed a DSTR-20 penthouse Dolby Digital reader on the Titanic in 1912, they would have only have changed it out about 19 times by now, perhaps less. But the DSTR-20 wins by a landslide when it comes to actually replacing the LED. With the Cat 702, you must remove two wires that are attached to the LED module and then reattach them to the replacement. If the ends get frayed you may need to re-strip it and they don't give you a lot of wire or space to work with. With the DSTR-20, you just loosen two screws and the module slides right off like a hooker's panties and the new one goes on. That's it! I do not understand why Dolby couldn't think of this. The Cat 702 does win slightly at LED intensity adjustment, though. There is a status light on the back that reads red for too low, orange for too high and green for just right. You just adjust the easily accessible trimpot on the back while a Dolby Digital film is playing so that the light is green, turned down just below orange. The DSTR-20 works the exact same way, but the light is on the operator side (a nice feature). But what does kind of rustle my dingleberries, though, is that the housing around the camera must be removed to adjust the LED intensity. You cannot do this easily while an actual movie is running as four tiny and easily dropable screws must be removed first. These screws want nothing more than to fall into the film path, preferably on the emulsion side, so it is best to remove them when nothing is threaded. This is a minor complaint, really. You simply won't need to adjust the LED intensity very often. Recently I did get a replacement LED and I had a hard time getting it to go below orange even with the trimpot dialed all the way down. It's just so bright! It still reads film great, though, and once it wears down a bit it'll be like brand new. You can hook up your oscilloscope or DRAS software and make super-precise adjustments if you reeeaaalllly want to, but the likelihood of ever actually needing to is very, very slim.

There is one thing that should be noted, though; if you have a projector capable of running 70mm and want to continue doing so, you're out of luck with the DSTR-20. Suffice it to say, there is no way to easily bypass 70mm film around the unit. The Cat 702 can be outfitted with an optional 35/70 bypass roller. If you want to bypass the DSTR-20 for any reason in 35mm, you'll have to go all the way around the outside rollers. So don't install that CDS reader on top of it!

Another thing worth mentioning is that the DSTR-20 requires a bit more film tension than the Dolby family of readers. If you are used to threading Dolby penthouse readers, you might thread the DSTR-20 incorrectly when you first encounter one. This will result in consistent "F's" throughout the movie which can sound like odd "chirping" in the soundtrack which is not appreciated by members of the moviegoing audience. You want the fun, springy tension rollers far enough apart to almost be able to stick a Sharpie marker/pen in-between. In booths like mine that feature both Cat 702's and DSTR-20's, it can be tricky for people to differentiate between the two. I just train people to put more tension on the readers which feature the "Video Status" light and less tension on the sexy ones from the future and it seems to work well. I'm certainly not complaining, just mentioning. Threading a Cat 702 with the tension of the BACP or higher can damage the perforations of the print, so it is essential not to get them confused. Unfortunately I see it all to often caused by those who consider projection an afterthought and do not make sure they are doing everything correctly.

Bottom line: Equal if not better performance to the Dolby Cat 702 in every respect and costs a few hundred bucks less? Hell yeah! I really don't see why anyone wouldn't choose this reader over any other that is available. Dolby swears they will get revenge, though.

--Joe Redifer

USL can be contacted at
BACP can be contacted here.
Joe Redifer is an experienced projectionist. At the young age of two, he crawled his way into the booth and taught himself how to thread the projector at the movie theater when the projectionist failed to show up to run Monty Python and the Holy Grail. The sold out audience of thousands praised Joe with cheers, cash and fresh diapers as he saved the show. These days Joe makes sure that the prints he shows are the cleanest in town and does his best to make sure each booth he is paid to enter functions at its peak capacity. Joe tries to keep a part time gig as a projectionist because it is just so enjoyable. Joe's day job is that of a video editor, sound mixer and DVD author. Joe can also do extremely simple technical work like setting up and wiring sound systems including B chain, swapping projectors, wiring automations and even changing the light bulb over the booth stairway!

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