Inovonics 222

[kc2ifr]

Wondering if anyone has used this AM processor and what did ya think?
Thanks in advance.

Bill

[W2XR]

Hi Bill,

I have this processor, and I find that it is superb for use with conventional plate modulated AM transmitters. It is user-adjustable in terms of allowing for symetrical or asymetrical modulation; asymetrical modulation in the positive direction is adjustable to 125% or better. It is a very clean sounding unit, and really increases the density (loudness or average level) of the modulation, largely due to the carefully controlled compression ratio between the audio input and limited audio output. Older limiters, particularly of the tube variety, do not exhibit the same level of control of the audio as the Inovonics, with the result that occasional peaks will slip through and overmodulate the transmitter.

As such, the 222 also provides very tight control of the negative-going peaks.

It also provides user-selectable NRSC preemphasis, so you can provide the same HF boost as mandated by the FCC for commercial AM broadcast stations. If you don't like the NRSC EQ, defeat it by the front-panel switch and use your own EQ curve from an external equalizer.

Note that I also have an Orban Optimod-AM 9100A multi-band processor. This is one of the best processors ever made for modern AM transmitters, and it employs a sophisticated clipping scheme to maximize the control and density of the modulation without the clipping sounding offensive, in addition to a superb AGC/limiting function. However, many plate modulated rigs cannot easily pass the clipped output waveform of the Orban, due to the ringing and overshoot that is created by the inherent complex non-linear impedances within the input and driver transformers, modulation transformer, modulation reactor and DC blocking capacitor, power supply LC filter network, power supply bounce issues, etc. This is apparent in use by difficulty in keeping the transmitter from exceeding the baseline during modulation with complex (i.e. speech) waveforms, while attempting to maintain the positive-going peaks at or above 100%. Frequently, in order to keep the negative going peaks from exceeding the baseline, positive going peaks have to be held down to about 80% or so with the Orban, when used in conjunction with a plate modulated rig. This is not the case with the 222.

I think the Orban is ideal for state-of-the-art AM rigs employing Class-E modulation schemes, etc., but one must be careful when using it with a plate modulated rig. Orban themselves clearly state this within the operating/installation manual for their processors.

Another processor that I have good success with, when used with a plate modulated rig, is the Dorrough DAP-310. It is also a multiband device, but devoid of the complex clipping scheme used in the Orban equipment. It does employ clipping in the output, but the clipping is really intended to capture any negative-going peaks that could overmodulate the transmitter, and normally the DAP-310 is set up so the clipper is rarely, if ever, actuated. These units are quite plentiful, but almost always require a lot of work nowadays to get going properly. I replaced nearly 40 electrolytics in mine, plus two FETS, and several other electrical parts as well when I first obtained it, and this is not at all unusual for solid-state broadcast gear run 24/7 over the 15 to 20 year lifetime of the equipment. Obviously, that's a lot of operating hours.

For these reasons, I recommend the 222 for use with plate modulated transmitters. They can be had very reasonably priced on e-Bay, and brand-new I think they can be purchased from the broadcast supply dealers for around $650.00. I paid $100.00 for mine from a local AM station, where it was on the shelf for years as a back-up/spare of last resort, and it was in pristine condition when I obtained it. Additionally, the 222 has been in continous production since the late 1980s, and Inovonics provides excellent support of their products. It is a great $$$ value insofar as broadcast-quality audio processors go.

Buy it; I think you'll be happy with the result. And no, I am not affilated with Inovonics in any way.

73,

Bruce

[W1DAN]

Hi Bill:

Bruce is correct on the above. I have owned a 9100A and really liked it (wish I had one again). I now use a Gregg Labs 2540, which is simelar to the 9100a. I added homebrew negative clipper and brick wall 6.5kc LPF filter. I have used many other processors and have studied the 222. It is a very good limiter.

That being said....

Limiters are limiters and affect the sound by restricting the natural dynamic excursions of your peaks. I believe you run a BL40 Modulimiter and it sounds very good on your station. If you add the 222, you'd get tighter peak control with more limiting and clipping (for what it is worth going through a tube rig with it's frequency and phase response non-linearities causing overshoot). You would also get the NRSC bandwidth limiting. Note Inovonics sells resistor kits to change the LPF values for even tighter bandwidth control...I like about 6.5kc myself.

I have determined that a very small amount of compressor overshoot clipping is helpful. More than that (and having owned an Optimod 9105A HF that is a real buzz saw to the audio..BTW, I'm looking for one cheep) the listener will notice the grunge.

With the Inovonics 222 after a compressor system (which I feel is most advantageous) you will get louder, but a bit less natural sounding.

Hope this helps!

Dan
W1DAN

[kc2ifr]

Hi guys,
I have the 222 installed and will respond later. Unfortunately my 500 pooped the bed and that is the xmitter I am using it on!!!!
More to come.........................................................
Bill

[W2XR]

Hi guys,
I have the 222 installed and will respond later. Unfortunately my 500 pooped the bed and that is the xmitter I am using it on!!!!
More to come.........................................................
Bill

Hi Bill,

Good to hear that you acquired a 222. Yes, please let Dan and me know as to your thoughts and experience with this limiter.

73,

Bruce

[kc2ifr]

Got the 500 back on the air and have been experimenting with the 222. From what I have seen so far this thing is a quality piece of equipment. It blows the BEHRINGER stuff out of the water...of course that wont take much! I will post more as I experiment with the set up. All reports have been positive.
More to come...........
Bill

[W2XR]

Got the 500 back on the air and have been experimenting with the 222. From what I have seen so far this thing is a quality piece of equipment. It blows the BEHRINGER stuff out of the water...of course that wont take much! I will post more as I experiment with the set up. All reports have been positive.
More to come...........
Bill

Hi Bill,

When you have the chance, please advise specifically what you like about the Inovonics 222; I'd like to see if your opinion and results correlate with mine.

Best 73,

Bruce

[Ed-VA3ES]

I just went to gaze upon my own Innovonics unit. It is a model 231.   Anyone have any comments about that unit? Opinions?

[kc2ifr]

Hmmmm,
Looks like VA3ES wants to hi jack my thread.........so be it.
I will reply to u folks about the 222 via direct email.

Bill

[Ed-VA3ES]

Hmmmm,  Looks like VA3ES wants to hi jack my thread.........so be it.
I will reply to u folks about the 222 via direct email.   Bill 

No, that wasn't my intention at all!    Continue with your thread.  Actually, anyone who wishes to talk about the 231 should email me.
Sorry about that.

[Steve - WB3HUZ]

When you have the chance, please advise specifically what you like about the Inovonics 222; I'd like to see if your opinion and results correlate with mine.

Bill:

Seeing as how you never replied to Bruce's question above, I don't see much to hijack. Are you just looking to cause trouble or actually looking for information?

[WD8BIL]

Looks like VA3ES wants to hi jack my thread....

Wow.... a bit possesive....
will we soon need permission to post a response??

[kc2ifr]

Steve,
Not looking to cause anything........are u? The topic of my thread speaks for itself. As for any response from me......I am still working on the setup and adding a new mic preamp ahead of the 222 before I do a complete review. Sorry if I didnt meet your time limit. Im always learning the "rules" on this board......

Bill

[W1DAN]

Hi Bill:

Take your time. There were two 222's listed on the FS section this week. I called and emailed the guy and verbally reserved one, but have not heard from him since, so he may have sold it out from me. Oh well...

This unit has a very good clipper and brick wall filter. You can order a resistor kit to change the cutoff frequency if desired.

Please keep us posted on your progress and opinion on this unit and your setup.

73
Dan
W1DAN

[Steve - WB3HUZ]

I asked a question. If you can't or won't answer it, then it would appear you have a problem. And that speaks for itself.

Steve,
Not looking to cause anything........are u? The topic of my thread speaks for itself. As for any response from me......I am still working on the setup and adding a new mic preamp ahead of the 222 before I do a complete review. Sorry if I didnt meet your time limit. Im always learning the "rules" on this board......

Bill

[kc2ifr]

I asked a question. If you can't or won't answer it, then it would appear you have a problem. And that speaks for itself.

Hmmmmmm,
I thought I answered your question..........what dont u understand Steve?

[kc2ifr]

OH BTW Steve,
If u want to talk about this off the board.....my email is wgr@roadrunner.com.

Respectively yours,
Bill

[kc2ifr]

OK....back to the topic at hand!  Ill explain with pictures (links) what equipment Im talking about for folks that may not know this stuff. This is the processor that is the topic of this thread:
http://www.inovon.com/?a=2&s=1&i=1
I was driving it with this......an ART ProChannel:
http://www.artproaudio.com/products.asp?type=79&cat=1&id=4
and I was not happy with it. So I just bought another one of these which I use with my 4X1 rig:
http://www.symetrixaudio.com/index.php?Show=14&Show1=&Show2=263

I have not changed to the 528e as yet but will this weekend. All that having been said......so far the results with the 222 have been great.

Stay tuned for more......

Bill

[kc2ifr]

I havent forgot to post my test of the 222.........I havent finished testing. This is taking longer than I expected.
 But I will say that so far so good.........well worth the money.
More to come.

Bill