Which AM Audio Processor?

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Fran3
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Which AM Audio Processor?

Post by Fran3 » Fri Sep 18, 2015 11:55 am

We are going to be replacing the AM audio processor as we want to improve audio quality... but, of course, budget is a part of the equitation that also has to be considered.

As a point of information the goal is to produce professional audio for both the spoken word and music.

Each of the units below are on the used equipment market and I would appreciate any comments you guys could share.

1 - ORB-9100A ORBAN 9100A MONO AM AUDIO PROCESSOR

2 - OMNIA 3 AM DIGITAL AM AUDIO PROCESSOR

3 - ORBAN 8100A/XT-2 SIX BAND LIMITER PROCESSOR

4 - INOVONICS 235 - AM BROADCAST AUDIO PROCESSOR

5 - APHEX 723 DOMINATOR II - PRECISION MULTIBAND PEAK LIMITER WITH PRE AND DE-EMPHASIS

6 - APHEX 320A COMPELLOR - COMPRESSOR / LIMITER - INTELLIGENT AUTOMATED GAIN CONTROL (AGC ) - FOR CONSISTENT PROGRAM LEVELS

7 - INO-222 INOVONICS AM NRSC COMPLIANCE PROCESSOR

And, if anyone knows of another unit that is on the market let me know as we will be glad to consider it.

Thanks for any comments.

bill981
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Re: Which AM Audio Processor?

Post by bill981 » Fri Sep 18, 2015 1:02 pm

1 - Still a great AM processor. Has "personality" modules on DIP headers. Supposed to just use the NRSC one, but I've used the "green" one for a better midrange. Still meets the NRSC Mask.
2 - Also a good processor. Still a lot of them on the air.
3 - The 8100A is an FM processor. The XT2 chassis was introduced a year or two later to add multiband limiting. Still FM so no asymmetrical modulation.
4 - A good budget processor
5 - Would be part of the chain, but not the final box in it.
6 - Better suited for either production (between console and recorder) or STL protection. Smooth, but again, not a final box before the transmitter.
7 - I'm not sure, but it sounds like it contains the NRSC pre-emphasis curve and 10 kHz high pass filter. Not for final processing.


If you can find an Orban 9200, that's good too.

Bill

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Re: Which AM Audio Processor?

Post by rich wood » Fri Sep 18, 2015 3:13 pm

Picking a good processor is important, but remember the limiting factor is the band width of the antenna. Do you have a sweep test of the antenna?

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Deep Thought
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Re: Which AM Audio Processor?

Post by Deep Thought » Fri Sep 18, 2015 4:04 pm

Of that bunch I'd get the Orban 9100 first and the Omnia second since you run music. What are you replacing?

The Inovonics 235 would be good for a backup but are not really competitive with 1 and 2. The rest don't get the job done at all.
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Re: Which AM Audio Processor?

Post by RodeoJack » Fri Sep 18, 2015 10:58 pm

I pretty much agree with DT here.

The first two are designed for AM, so I'd stay with them, if those are your only choices. Do some research on any 9100 you consider buying. They're old enough that most are candidates for capacitor replacement. Bob and Kim Sacks ( www.optimod.am ) do a great job rebuilding them and will upgrade chips and power supplies as needed. That can cost from $700 to $1,500 to bring an older Optimod to a condition that's really competitive with modern processors, so consider this as you look around.

I would stay away from the 235, because you're running music. This processor is OK for talk formats in a non-competitive market, but percussion and sibilance pokes huge holes in the audio, and that tendency can't be adjusted out of the processor without other (worse) side effects taking over. Because you're playing music, I'd stay away from this one. I had to set up a couple of them in a small town last week where there was no other choice. They're legal, but I wasn't happy, having to leave the station sounding less than I would have liked.

The Dominator, with Pre / De-emphasis was set up for FM. I've seen one case where a station used it before an STL... one of those "use to taste" applications, I think. You'd need another box for NRSC and asymmetry (positive peaking), which the Dominator might eliminate, No real usefulness here that I can see.

The Compellor is a great AGC. Use it with one of the AM boxes for a leveler if you have an STL or widely varying audio levels. Really shouldn't be needed otherwise.

The 222 is what it says... a "compliance processor". It was initially designed to match up with older, pre-NRSC processors. It's still available, but its usefulness is pretty much a matter of opinion among engineers. Pretty much every AM processor that's even marginally-modern includes the functions that the 222 provides.

My opinion only... possibly worth at least what you paid for it.

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Re: Which AM Audio Processor?

Post by Joe Friday » Sat Sep 19, 2015 2:39 am

Not on your list, but worth considering is the Omnia ONE AM. I have one on a news talker driving a Nautel J1000, and it does a worthy job. The old Orban 9100 is hard to beat if you can find one used. I would avoid the Inovonics 222. Some very basic compression, but little else. I had a station that used the Inovonics 235, and it did an OK job, but it would not be my first choice. Good luck!

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Re: Which AM Audio Processor?

Post by ChuckG » Sat Sep 19, 2015 2:08 pm

In addition to the other suggestions, you might look at BW Broadcast's DSPX-AM. Under $2500 gets you a competitive digital processor, you can schedule different presets at different times for talk, music, etc.
I have one in service and am eyeing up a second.
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Bill DeFelice
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Re: Which AM Audio Processor?

Post by Bill DeFelice » Sat Sep 19, 2015 3:56 pm

A second vote for the Omnia One, as I have one that I can flash for any use for a loaner when I need it to pull emergency duty. I'm also a fan of the late Steve Hnat's TriMaze AM processor. A fellow engineer introduced me to the processor at the station he worked at and I met Steve at the Syracuse SBE convention a few years before his passing.

I also have an Omnia Classic AM at a station that sounds quite good with a minimal amount of pre-processing.
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bmcglynn
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Re: Which AM Audio Processor?

Post by bmcglynn » Thu Sep 24, 2015 5:04 pm

Another semi-vintage set to add to your list is the CRL set. The CRL SMP, SEP, and SGC units do very well on music. You will need 3 units: The AGC, the Processor, and the limiter.

The AGC-400 (Mono) and SGC-800 (Stereo) are a great AGC to put before your processing stack or STL.

The SEP (400/800)is a 4 band limiter/compressor.

Both of these units go before the transmitter for limiting and asymmetry generation:
- The SMP-900 and 950 are final limiters (and a lot more) for C-QUAM AM Stereo.
- The PMC-450 is for mono-AM.

We have a music-focused AM format on one of our stations and the CRL units make it sound great. If you watch eBay, you can usually get an entire set for under $1,000. These units are late 80's and early 90's vintage, and may require some new caps (or may not). In any event, I am very pleased with the sound from our CRL gear.

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Re: Which AM Audio Processor?

Post by Bill DeFelice » Thu Sep 24, 2015 6:04 pm

bmcglynn wrote:We have a music-focused AM format on one of our stations and the CRL units make it sound great. If you watch eBay, you can usually get an entire set for under $1,000. These units are late 80's and early 90's vintage, and may require some new caps (or may not). In any event, I am very pleased with the sound from our CRL gear.
FYI: If shopping for CRL gear the newer versions have the square CRL Systems logo on their front panels.
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Deep Thought
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Re: Which AM Audio Processor?

Post by Deep Thought » Thu Sep 24, 2015 8:07 pm

bmcglynn wrote: These units are late 80's and early 90's vintage, and may require some new caps (or may not). In any event, I am very pleased with the sound from our CRL gear.
Make sure they are NRSC compliant, too.
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Re: Which AM Audio Processor?

Post by ChuckG » Thu Sep 24, 2015 11:47 pm

bmcglynn wrote: - The PMC-450 is for mono-AM.
There was a resistor change we used to do to those to allow more limiting before the clippers kicked in. Cleaned up the box without losing loudness on music. I've forgotten the exact details, not having worked on one for at least a decade.

SGC-800 is still one of my favorite gain controllers to put in front of an STL, when you can find them.
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Re: Which AM Audio Processor?

Post by kkiddkkidd » Fri Sep 25, 2015 7:43 am

bmcglynn wrote: and may require some new caps (or may not).
And may require modules that are unobtainium.
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Re: Which AM Audio Processor?

Post by Xenirad » Wed Oct 07, 2015 4:00 pm

I love the Omnia processors for FM but have not had great success with using an Omnia One for AM as it does nnot have very good peak control. The best AM processor I have used is the Vorsis VP-8 which sucks on FM but really cranks on AM with precise peak control. It is all just personal opinion of course.
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Re: Which AM Audio Processor?

Post by Conelrad » Sat Dec 26, 2015 10:20 pm

A dinosaur that always sounded killer was the Dorrough DAP-310.

DG

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