All of the Ultra auditoriums had (roughly) the same amount of hiss. All of the Dolby auditoiums were also identical to eachother in regards to hiss. You can't hear the hiss when there is noise in the room or people talking, non-sync music playing, just stating that there is more hiss than the Dolby's. I really don't think this is such a big issue. I'm sure the amps themselves contributed to the hiss, but that's a different review.

I'm fairly certain that these units meet factory specs. But you can take comfort in knowing that I reviewed exactly what Ultra sends out, meaning you will get the same thing (if they still make these units... I think they have gone the way of the digital processor like the CP500, etc).

Also, my reviews certainly are NOT written just so everyone can agree with them.

In my younger and more naive days, I always recommended that amps be run wide open, and then the processor gains should be set for the proper auditorium level. The SOLE reason for doing this was so that if an amplifier died, it was very easy for anyone to replace since there would be no concern about setting the new amp's gain. Just turn it all the way up, and there you have it. This was even more of a concern for biamp systems where the gains needed to be precisely set.

However, most processors have additional stages AFTER the fader, and these stages will always contribute SOME noise although it may be very little. If an amplifier has enough gain, this noise will be amplified to the point of audibility.

Techs from the field began to tell me that this was not the optimum way to do things. So later on I started recommending that amplifier gains be set 6 to 10 dB lower and then turning up the processor ouput levels to achieve the proper levels. The hiss decrease is sometimes dramatic by doing this. The gain STRUCTURE has been changed to put the optimum amounts of gain at each point in the system. The equipment has to be looked at as a system where the parts are optimized to work together as well as possible.

And regarding the comment about amps hissing, generally speaking amps are pretty quiet devices with S/N ratios around 100 dB or better, but do not be fooled, ALL electronic equipment has noise regardless of who makes it. The trick is to make sure every part of the system works at its best with every other part.

Now I will grant you that some equipment may be measurably and audibly more noisey than others, but for the most part, current products are pretty good in respect of noise. It is best not to think that you can simply treat all equipment the same in terms of setup procedures, however. Be flexible a bit and learn what works best for each type of equipment you have, and then there should be less opportunity for complaint. I have talked with several techs who take this approach, and it is amazing what good performance they can get out of any manufacturer's equipment.

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Oscar Neundorfer
Chief Engineer
SMART Devices, Inc.

I really like Joe's reviews for their practical "real-use" comments, which I think (ultimately) are of more use.

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Anyway, I understand why you guys would appreciate official specs and performance numbers. I am a tech head and love seeing those same numbers on paper, even if they don't make a noticeable difference in the real world. But keep these two things in mind:

1)These are not lab tests. These are all tested in the real world, working in a real booth and playing real films, not just test noise patterns, etc...

2)I do not have all of the equipment to administer such tests, cannot currently afford it, and do not currently have the time to perform those tests if I did have the equipment.

Other than that, I hope everyone enjoys the reviews and finds them valuable.

As far as leaving the amp gains wide open, I do agree with Oscar, but many times it isn't feasable. In our big house we cannot meet the analog subwoofer level with our CP500's out put cranked to the max. Even with the amp gains maxed out, it still falls short. Of course, digital subwoofer level is easilly acheived. If I could have my way, all amp gains would be set to 12 o'clock, but I can't do that. I also like standardization.

I think in the type of review as Joe does it really is one man's opinion based on personal experience and it should be taken as such. It isn't a quantitative analysis as you would expect from a magazine review.

In the case of Ultra-Stereo's JS series, I have found without exception what I would term excessive hiss, regardless of gain structure. Just walking into the auditorium, you get assaulted by hiss as compared to say a current CP-500 or CP-65. The early CP-500's had the same problem.

As far as distortion goes, I have yet to be in an auditorium Ultra Stereo equipped and not been able to tell that it was an Ultra processor (on analog...harder to tell for digital).

Steve

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You can hear the hiss when the auditorium is quiet. They do have trouble switching between formats w/ DTS. AND they do blow a lot of power supply cards. I've only had one bad format card, though.

I like them but I DO wish we had Dolby. To me it's like buying a cheap computer, or something like that... You CAN get a Pentium chip in a Packard-Bell, but wouldn't you rather have something like a Gateway? (Or whatever)

Same goes for processors... Yes, Ultra*Stereo has SR decoding but wouldn't you rather have the original?

Joe, Let me know if you ever want SN and distortion figures taken on a unit. I'd be glad to do it for you.
Mark

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