Film-Tech Forum ARCHIVE: Sondor "Soundhouse"

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Posted by Thomas Jonsson (Member # 1902) on 10-05-2003, 03:09 PM:

Sondor have developed a penthouse reader called "Soundhouse" capable of reproducing not only DolbyDigital but also reverse scan analog and DTS - in the same unit.

Has anyone seen or heard anything about it?

Thomas

Posted by Brad Miller (Member # 2) on 10-05-2003, 03:12 PM:

PDF file

Posted by Michael Schaffer (Member # 1204) on 10-05-2003, 04:05 PM:

Looks interesting. Has anyone seen it in action? Does the time delay buffer introduce a noticeable degration of the analog sound quality?

Posted by Richard Fowler (Member # 893) on 10-05-2003, 04:46 PM:

Kinoton and MegaSystems are using audio delay on some products.

Posted by Antonio Marcheselli (Member # 373) on 10-05-2003, 06:14 PM:

Very Interesting!!

Why DTS should have white light for its reader?

Bye
A

Posted by Gordon McLeod (Member # 33) on 10-05-2003, 07:13 PM:

Interesting point since I would wonder about the sharpness of the contrast with a cyan dts timecode on a white light unit

Posted by Brad Miller (Member # 2) on 10-05-2003, 08:06 PM:

I'm curious as to how well it tracks SRD in comparison to the cat702 Dolby penthouse.

Also, what cost?

I thought the reason BACP did not make a combo SRD/DTS reader had something to do with one or the other of the two companies not wanting a dual reader being made. Can anyone shed some light on this? Sam?

Posted by Manny Knowles (Member # 1171) on 10-05-2003, 08:46 PM:

What are the key differences between the 701 and 702 readers?

Posted by Richard Fowler (Member # 893) on 10-05-2003, 09:45 PM:

The 702 has no power supply since the unit taps off the power available on the digital cable between the Dolby processor and the reader. Visual signal status displays are another feature. These where first introduced on the BACP / USL digital penthouse.Sondor is very specialized for the studio market, so a combo head of the two surviving digital formats is a good idea.
There is a design for a Dolby Digital reader which mimics the simple layout of a DTS type reader.....did the shrinking market or technical problems make this an aborted project?

Posted by Michael Schaffer (Member # 1204) on 10-06-2003, 01:38 AM:

quote:
Kinoton and MegaSystems are using audio delay on some products.

Indeed, but the only digital time delayed buffer systems I have worked with were the ones on the FP38E - for 16mm mono. I wonder if the time delay in this unit leads to any degration of the optical Stereo quality.

Posted by Ray Derrick (Member # 1001) on 10-06-2003, 05:15 AM:

It looks like a nice unit although vernier adjustments for the optics would have been a nice improvement. What is it with sound reader manufacturers? None of them offer an intelligent way of making fine adjustments to the alignment. Maybe I need to design one. [Smile]

Back to the Sondor, I would have thought that any advantages obtained by putting the analog reader on the penthouse would be outweighed by the disadvantages. Presumably the output from the analog reader has to be amplified up to line level to get a decent dynamic range through the digital delay system and then attenuated back down so as not to overload the cinema processor's preamp. That's going to add noise. Also if you install one of these with a CP650 and a QSC monitor, the analog audio will have been converted to digital and back three times by the time it gets to the speakers. Just think of all those compounding quantisation errors.

Posted by Stephen Furley (Member # 1277) on 10-06-2003, 06:57 AM:

Can this thing provide a digital output from the analogue track? That would be the obvious way to go if using a digital processor.

Posted by Peter Hall (Member # 695) on 10-06-2003, 09:12 AM:

Ray -

Tis a std basement set up, with the Dolby analogue preamp card. I guess the delay is at this level ? Have not use in a standalone situation but look after some Nova projectors with these in - a sod to change the LEDS (early Kinotons are a DREAM compared to these - next time will take my 6 year old as his sized fingers are more suited than mine !) but otherwise great. We quoted one for a Ernemann 8 QCing prints in a lab but Dolby were a little hesitant on using a soundhead with a delay

Posted by Pete Naples (Member # 761) on 10-06-2003, 02:52 PM:

Seems odd all the 'softly softly' on delay. It's not like delay is exactly a new or poorly engineered audio technique. Mind you studio quality delay processing is quite expensive, adding to the cost of what is probably quite an expensive rep-set.

Posted by Peter Hall (Member # 695) on 10-06-2003, 11:52 PM:

Yep, plus this thing states a static delay of 220 frames - what happens if you want to use one on a DP70 ? Or on a Vic 4 or smaller machine ?

The digital delay on the FP38E is fun to play with - you have to offset this whenever you change projector speeds (seems that this bit of logic has bypassed the designers )

Posted by Ray Derrick (Member # 1001) on 10-07-2003, 12:42 AM:

Peter, so I gather this unit is purely for studio use and that you're saying it comes complete with a Dolby pre-amp card. Are the pre-amp and delay somehow built into the chassis or supplied in a separate chassis or rack mount box? If you wanted to use it in a cinema, you would need to be able to access the inputs to the NR cards in the cinema processor. Not too many processors allow for that without modification to the backplane, (with the exception of Panastereo of course).

Pete Naples, no softly's on digital delay itself. The point I was making (and I suspect Michael was alluding to) is that each time you convert to digital and back again you lose something. I am sure you would agree that in an ideal audio world, you convert to digital once and stay there, rather than keep converting back and forth.

Posted by Stephen Furley (Member # 1277) on 10-07-2003, 01:51 AM:

Peter, did you mean 220 perfs? 220 frames would be 13.75 feet. A quarter of that sounds about right, allowing for loops etc.

Posted by Michael Schaffer (Member # 1204) on 10-07-2003, 03:06 AM:

quote:
Presumably the output from the analog reader has to be amplified up to line level to get a decent dynamic range through the digital delay system

Why is that? Can`t the signal be quantized at a high resolution at a lower than line level? Please explain further!

Posted by Pete Naples (Member # 761) on 10-07-2003, 05:02 AM:

Yeah that's a good point Ray, with every A-D and D-A conversion the circle gets squared a little more.

Michael, I don't think I've ever seen quality A-D convertors that work at SVA cell level, so it would seem logical that line is the way to go. I'd hazard a guess and say that the line level signal might well have a better s/n ratio, there could also be slit loss eq applied at that stage. I think the Raytheon laser units on modern Ernemman do this as I've never had to apply any slit loss to them.

Posted by Frank Angel (Member # 248) on 10-07-2003, 05:24 AM:

Perhaps they looked at the analog capability as only a "backup" rather than a primary source for either of the two digital tracks and only to be played in dropout emergency. Then, if you had an analog-only print, you could use the output from the standard basement soundhead. Not many projectors can be run without the soundhead drive anyway, so it is going to be there in most setups. I have two situations where this unit would be a very elegant way to go -- it would give me a reader for both digitals (sorry Sony), and for older analog prints, I would still use the basement soundhead reverse scan reader. There I could then swap the visible red exciter for Kelmar's infrared LEDs, which they still have in stock. I am presuming that this unit has the same or better tracking abilities "genuine" Dolby and DTS penthouses, I would then have the best of all worlds, even for reverse scan analog of older silver tracks prints since my soundhead could be optimized for then using infrared.

I am assuming this thing would be cost-effective and save us some $$ savings over purchasing separate equipment for the individual digital formats....says the guy living in the not-for-profit booth.

Frank

Posted by Ray Derrick (Member # 1001) on 10-07-2003, 06:12 AM:

Michael said "Can`t the signal be quantized at a high resolution at a lower than line level? Please explain further!"

Yes of course, however A to D converters have their limitations in terms of noise, linearity etc. If you sample audio at too low a reference level, the A to D converter's inherent limitations can become significant and degrade the audio signal.

Posted by Gordon McLeod (Member # 33) on 10-07-2003, 09:28 AM:

At one time USL distributed a reverse scan reader that digitized the analogue track and removed noise in the digital domain but I don't think anything ever happened with it

Posted by System Notices (Member # 2357) on 03-13-2011, 07:59 PM:

It has been 2714 days since the last post.

Posted by Fabian Schreyer (Member # 5120) on 03-13-2011, 07:59 PM:

Has anyone got this reader till today? Or does anyone know, how much they are asking for it?

Posted by Paul Gordon (Member # 3320) on 03-22-2011, 08:40 AM:

7,000 euro for the combo head that can do SRD/DTS/SR... kinda pricey but cool.

Posted by Bobby Henderson (Member # 840) on 03-22-2011, 03:02 PM:

I didn't know such a product existed; I figured such a thing might violate some existing patents.

In one of the 70mm related discussions involving the dead Cinema Digital Sound format I talked about how it might be really cool to have a single all-purpose film sound reader that could optically read any digital audio format off a film print.

The custom reader might be a way to resurrect CDS and play the audio off any 35mm or 70mm CDS prints if any such prints still exist. Film readers using current technology might have better luck tackling a CDS audio track than the readers made in 1990.

The Sonor Soundhouse digitally reads SR optical off the film print, but I don't know if it's possible at all to customize it to where it could accurately see CDS data on a 35mm print. Too bad they left out SDDS capability.

Posted by Sam D. Chavez (Member # 1841) on 03-23-2011, 12:59 AM:

Bobby, you're dreaming here.

BACP and USL were going to do DTS, analog and SR.D in one package that eventually became the DSTR-20 but it didn't make sense because very few customers would buy both Dolby and DTS for a new cinema.

CDS was way hard to do as their own reader could not reliably read their track.

SDDS is a whole other thing as they are outside the imaging area of all the other soundtracks.

Posted by Louis Bornwasser (Member # 3063) on 03-23-2011, 07:16 AM:

I thought that sdds was just an updated cds. No? Louis

Posted by Sam D. Chavez (Member # 1841) on 03-23-2011, 09:59 AM:

Louis

It had similarities as some of the same individuals designed it but it's a whole different unit, much more sophisticate and unlike CDS, it had some redundancy.

One big difference was the bits are located on both sides of the film way outside the standard area reserved for soundtracks. It would be very difficult to adapt the SR.D penthouse reader to pick this off.

Basement readers are out of the question as the sound is in dead sync with the picture frame, so negative delay would be required. Nice trick.

Posted by Sean Weitzel (Member # 244) on 03-23-2011, 11:10 AM:

Is CDS in sync with picture or is it offset?

Posted by Sam D. Chavez (Member # 1841) on 03-23-2011, 11:43 AM:

As I remember, in sync and this was a big selling point as the picture and sound would disappear together with film damage. This was deemed important by someone.

This also made it easier to do editorial like that matters now.

Posted by Bobby Henderson (Member # 840) on 03-23-2011, 10:45 PM:

quote: Sam D. Chavez
Bobby, you're dreaming here.

Yes, I agree. But it's kind of fun. Hypothetically speaking it should be possible to create a penthouse mounted film reader that can see data for SRD, DTS and SDDS as well as dead formats like CDS or LC Digital and perhaps even digitally read the optical analog tracks too.

Regular movie theaters have had no need for this sort of thing because most did indeed only install one of the digital sound formats. It was rare to find a screen that had two or three digital sound formats installed.

35mm film is on its way out of first run movie theaters, but I don't see film being eliminated completely. Art house theaters, revival houses, colleges, etc. will still have a need for running film prints. What are they going to use to play the audio in the long run, like 10 or 20 years from now? If there's anything I know about digital hardware is it all breaks eventually and the companies making the hardware don't make replacement parts for very long at all. Theaters playing film prints could eventually be stuck playing the audio in analog once critical pieces of equipment fail.

A lot of the digital sound processing hardware that was so common in the 1990s and this past decade is already in the process of dying. I'm sure plenty of first and second generation Dolby and DTS processors have bitten the dust. Same for SDDS hardware. That format is at least comatose and heading for the grave since no new hardware for it has been made in several years.

If some custom, multi-purpose film reader can at least properly see the audio data on the print it might be able to send it to some type of digital audio processor or computer to decode the audio or use the film print data to sync audio from a hard disc drive.

DTS/DataSat has sort of tip-toed in that direction with their XD-10 and XD-20 processors. They not only decode the theatrical DTS format but can also decode home theater DTS and even the home theater variant of Dolby Digital. Why not add more audio formats to the mix?

quote: Sam D. Chavez
CDS was way hard to do as their own reader could not reliably read their track.

I wonder how much of the problem was due to film printing issues as opposed to issues with the reader. CDS audio had a bit rate of around 6 million bits per second. I'm sure there was some considerable challenge in getting the CDS data onto 70mm prints and 35mm prints consistently.

By comparison, on 35mm film Dolby Digital runs at only 1/12 the rate of CDS, around 550 kilobits per second. That includes all the error correction data; the actual DD track is encoded at only 320kb/s. The data is able to be printed at a larger, easier to read size, making it more robust at overcoming inconsistencies in film printing.

But if the real problem with CDS was its film reader we have had 21 years worth of advancements in LEDs and CCD/CMOS imaging chips. New technology could probably do a far better job of reading a CDS audio track if the CDS audio track was reproduced on the film print well enough.

quote: Sam D. Chavez
It had similarities as some of the same individuals designed it but it's a whole different unit, much more sophisticate and unlike CDS, it had some redundancy.

SDDS operates at a much lower bit rate than CDS, about 1.2 million bits per second (Sony Professional ATRAC codec). It has a primary digital track and a complete backup digital track as well as the analog track for final backup. And I have heard SDDS do the double-fail from primary digital to secondary digital to analog plenty of times -most often with very worn AMC Theaters policy snipes.

quote: Sam D. Chavez
One big difference was the bits are located on both sides of the film way outside the standard area reserved for soundtracks. It would be very difficult to adapt the SR.D penthouse reader to pick this off.

The sort of reader I'm hypothesizing would have to be an entirely new design, maybe something where the imaging pick-ups can be shifted to target different positions on the film print.

Obviously, this sort of idea will be rendered moot if movie studios decide to only distribute DCPs exclusively and push the film projectors of specialty theaters into moth balls or the trash heap.

Posted by Louis Bornwasser (Member # 3063) on 03-24-2011, 06:26 AM:

Future 35mm use will revert to analog and Dolby Digital, at most. Other formats, such as anything special, will fade and die. dts, in particular, will fail as discs are lost. Frankly, the others (cds & sdds) weren't that popular even at their peak and suffer from lack of factory support.

The real failure point of 35mm will be the lack of support (factory, dealer, and technician) as these people retire and die. Louis

Posted by Steve Guttag (Member # 268) on 03-24-2011, 08:28 AM:

Actually Louis, I have more high hopes for DTS/Datasat than for Dolby Digital.

How many decoders are there for Dolby Digital? Right now...just the CP650. The DA20/CP500 are pretty long discontinued and lord only knows how long they will be repairable.

As for DTS...there are more of those discs out there being horded than you can imagine...also, it isn't a real trick to recreate them or even port the technology to a discless based one. Likewise...the decoding scheme won't be all that tricky. In fact, I could see a day when digital for film will also be a PCM track running off of a non-special computer with the audio files sent in just like for DCinema. Storage space just isn't all that big a deal anymore...all that would be left is syncing the projector to the player...a DTS type time code would be quite handy...if you don't have a pulse-tach set up already.

-Steve

Posted by Paul Gordon (Member # 3320) on 03-24-2011, 08:35 AM:

I agree, DTS discs can be copied easily, uploaded to hard drives, the DTS processors themselves are very basic boxes, that seem to keep on chugging. Just look at all the people still using the DTS6! Dolby Digital blows for older, dirty, splicy prints, it will always drop to analog.

quote: Steve Guttag
As for DTS...there are more of those discs out there being horded than you can imagine...also, it isn't a real trick to recreate them or even port the technology to a discless based one. Likewise...the decoding scheme won't be all that tricky. In fact, I could see a day when digital for film will also be a PCM track running off of a non-special computer with the audio files sent in just like for DCinema. Storage space just isn't all that big a deal anymore...all that would be left is syncing the projector to the player...a DTS type time code would be quite handy...if you don't have a pulse-tach set up already.

Posted by Bobby Henderson (Member # 840) on 03-24-2011, 10:07 AM:

quote: Steve Guttag
How many decoders are there for Dolby Digital? Right now...just the CP650. The DA20/CP500 are pretty long discontinued and lord only knows how long they will be repairable.

I assume Dolby's CP750 only works with digital projection setups. The diminishing support for digital sound processes on 35mm film may indeed push digital sound playback for film onto hard discs in computers or devices like a DTS/DataSat XD-20. A hard disc would allow uncompressed Linear PCM 5.1 playback. That sort of thing would be very do-able for old prints with DTS time code.

Then there's the issue of many 1990s movies using only one digital sound process exclusively. The ones with DTS only, such as Jurassic Park or Schindler's List wouldn't be such a big deal. But dozens of movies were released only in SDDS/SR (such as Desperado) or SRD only (such as The Lion King or The English Patient). Without any working digital sound film reader and processor to decode the audio track the 35mm film print will be stuck playing audio in analog. An up to date reader that could at least properly see the data on the print could give a computer system an opportunity to process it.

Another question I thought about: what's more likely to fail first, the film reader or the digital sound processor? Are the connection standards they're using obsolete? For instance if one had an old Dolby Digital reader that still worked would there be any way to connect it to a computer system to process Dolby Digital data on a film print?

Posted by Aaron Garman (Member # 1653) on 03-24-2011, 11:08 AM:

quote: Bobby Henderson
The diminishing support for digital sound processes on 35mm film may indeed push digital sound playback for film onto hard discs in computers or devices like a DTS/DataSat XD-20. A hard disc would allow uncompressed Linear PCM 5.1 playback. That sort of thing would be very do-able for old prints with DTS time code.

This is why I always loved DTS. Sure, Dolby Digital is convenient now but way down the road, DTS is completely viable and upgradable. Even with film dying for first runs, places like ours are going to continue to run this stuff I'm sure for years to come. Sadly, we don't have DTS installed...just a CP650.

AJG

Posted by Steve Guttag (Member # 268) on 03-24-2011, 11:54 AM:

Dolby Digital always put the "brains" of the system in the processor. The output from the reader is a video signal, of sorts. As such, one would have to come up with a unique input module to use a computer to try and "read" the soundrack.

DTS...on the other hand...is just a pulse track...big deal. It is so basic, I've handled 16mm movies were they merely recorded the time code on the 16mm analog track...hook the 16mm preamp output to the timecode input and it worked (DTS did make a buffer board that would clean the signal and get well defined edges on the pulse).

Sony has always split the brains up between the reader and the player with the player having the bulk of the work.

-Steve

Posted by Louis Bornwasser (Member # 3063) on 03-24-2011, 06:21 PM:

So. . . sr wins by default. Future 35mm will be analog. Louis