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Loud Audio

It is entirely possible to have more than 100% modulation, in fact every AM broadcast station in the country does it every day. As mentioned before in this thread the key is asymmetrical modulation where the positive peaks are greater than the negative which allows the positive modulation to exceed 100% before the negative peaks hit 100%.The only reason the positive peaks flat top is because you run out of headroom in the audio amp. Exceeding 100% on the negative is what causes distortion by switching the carrier completely off and back on.You use an oscilloscope to measure the modulation waveform and determine the level of modulation regardless if it is greater or less than 100%. It is all in relation to the unmodulated carrier level. In my former life as a broadcast engineer I had a transmitter with modulation problems where it would SNAP! and POP! on peaks. After performing repairs we cranked the mod levels up to test it. We were running 100% negative and nearly 200% positive modulation. It was loud as hell but clean. Of course this was on a dummy load as anything over 125% on the air is illegal in the industry. :whistle: So mod levels in excess of 100% is quite possible to do however you need to know how to do it as it is not a simple matter of cranking everything to eleven.:blink:

Sometimes it is hard to know when to believe something and not, when on a forum, but that makes sense and I learned something new.

But that still brings me back to the original topic. I think my thread has taken a different turn. I have had radios tuned and such, DTB is my guy for my radio tunes. I'm not very interested in a power mic. I don't see the need for them in most circumstances. I usually have a preference of a good noise canceling mic or a good omnidirectional.
I am curious to know, watt for watt, if someone can list best to worst for loud and thundering radios. If you had two stationary locations; station 1 keeps the same receiving radio and antenna. Station 2 takes every Stryker, Magnum, Cobra, Uniden, etc. and running them all at a constant output level (4W DK and 20W peak) through the same antenna. Station 1 will hear which radios the loudest. Atmospheric conditions not being a variable. I expect that old school Cobra 29 and Uniden 76XL would make it near the top. But I am just guessing.
 
Sometimes it is hard to know when to believe something and not, when on a forum, but that makes sense and I learned something new.

But that still brings me back to the original topic. I think my thread has taken a different turn. I have had radios tuned and such, DTB is my guy for my radio tunes. I'm not very interested in a power mic. I don't see the need for them in most circumstances. I usually have a preference of a good noise canceling mic or a good omnidirectional.
I am curious to know, watt for watt, if someone can list best to worst for loud and thundering radios. If you had two stationary locations; station 1 keeps the same receiving radio and antenna. Station 2 takes every Stryker, Magnum, Cobra, Uniden, etc. and running them all at a constant output level (4W DK and 20W peak) through the same antenna. Station 1 will hear which radios the loudest. Atmospheric conditions not being a variable. I expect that old school Cobra 29 and Uniden 76XL would make it near the top. But I am just guessing.
if you run all radios with same dk and swing i doubt that you,ll see much difference. [if any]
EXPECTION magnums have a speech processor built into them this imo would give them
a very slight edge nothing majior though. i understand not wanting a power mic i also use
them 99% of the time.now if you didnt want a power mic with a built in speech processor
you can get them installed in your radio. bobscb does it . all other loud radios you talk about probaly have clipped limiters NOT GOOD
 
If everyone would concentrate on getting 100% CLEAN modulation and stop this ,IMO stupid, quest for a LOUD radio the band would be so much better and there would undoubtedly be less interference. Personal feelings is that it is all an ego thing. Some people need to be faster than others. Some people need to bench press a little more than the next guy. Some people need to be just a little above the next guy to boost their ego. IMHO a LOUD radio is that way for the same reason. Some say they need it to get over the next guy. Back in the heyday of shortwave broadcasting it was all about getting a signal through to the target area and being heard. Hmmmmm.....much like the reason most folks want loud radios. The huge multi-hundred kilowatt transmitters mostly ran at about 85-90% modulation levels and no more. The main effort was in producing as strong a signal as they could because after all if you can`t get a signal into the receiver end than no amount of modulation is going to help you. This is my opinion mind you and others are most certainly going to have a different one.
 
Actually, you should say, "Hitting 100% on the negative is what causes distortion," since exceeding 100% is impossible, due to the fact that once you hit 100% the carrier is switched off

I didn't say that because hitting 100% on the negative is possible without causing distortion due to carrier cut-off. Hitting 100% exactly will not cause the distortion you speak of as long as it is achieved at an instantaneous point in time.I suppose this is an issue of splitting hairs trying to distinguish between 99.999% and 100.001%. The longer the carrier is actually cut off, as indicated by a flat line in the middle of the waveform as observed on an oscilloscope, the greater the distortion tends to be. Hitting more than 100% on the negative peaks is impossible as you you say for the reason you mentioned.

On the odd occasion over the 22 years I was in broadcasting we would blow a tube in one of the AM transmitters. If it was an RF tube the transmitter power output would drop to about half the normal output however the modulator was still producing enough audio to fully modulate the transmitter at full output. This would result in terrible distortion, sometimes becoming nearly unintelligible on the air. There were extended periods of time when the carrier was cut off. After replacing the tubes and adjusting mod levels again I could obtain 100% negative mod levels bringing the carrier just to the point of cut off with no discernible distortion. Again.....was it 99.999% or 100.001%. In reality it does not matter.
 
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Not once did I mention ANYTHING but clean audio signal. Not once did I mention use of power mics, supertunes, or anything to the likeness. I have specified NOTHING but 100% modulation levels and quality CLEAR audio. It is also nothing about ego or I wouldn't have mentioned modest output levels. It is about trying to find the best quality piece of equipment before I spend money on another radio.
Plain and simple, some things are built with better performance than others. I may not be able to explain the why and how, but it is quite conceivable to assume that with equal output wattage that one radio can sound louder and cleaner than another. I am simply asking, if it is possible, for a list of best to worst of radios that can perform this way. If I asked for a list of good performing SSB radios, I would get answers like "side mice 148 GTL, Uniden Grant XL, Cobra 146 GTL." Why can't one ask what is a good performing radio on AM, without the backlash of everyone assuming that everyone with a CB wants a dirty sounding splatter box? Yes, I play on AM. Yes I want a loud radio. I want a loud radio AND have it sound good at the same time. I have heard radios that sound so good that everyone steps on each other to talk to that one station, because they sound so good.

A radio can be loud and still have QUALITY audio. I have specified the desire for it in almost every post I've made on this thread. I am NOT asking what power mic to use to over-modulate. I am NOT asking who can tune 100W from a Cobra 29 (obvious exaggeration). I am NOT asking about ridiculous tunes. It is everyone else who are making such suggestions and assumptions even though I keep repeating that is not what I am looking for. Each reply I make specifies that I am NOT interested. If that is what I wanted, I would hop onto Radio"craptive" radios and ask for the most "bodacious super whackpack" they offer.

Being that I don't have to money to buy every piece of equipment out there for a comparison, I thought I would ask of other's experience.

I can only compare the radios I personally have. Currently my best is DTB tuned Uniden Grant XL, then my Johnson Messenger 4230 (though it has only been heard through a 1/2 wave dipole giving it an unfair advantage over the other mobile installs) next is my DTB tuned Cobra 29 (china made). My Uniden PC76 would beat my Cobra 29 (china made) but it is broken. My Galaxy 929 and the 95t2 sound about even(with the 95t2's V-power turned down to comparable output. Obviously the 95t2 is the biggest radio with it turned up but I am concerned with comparable outputs) but they are both next. Then my Cobra 25. Then the Uniden 510XL, and last is the Midland 1001z (which is horrible). I haven't yet hooked up my Bells reconditioned Madison to compare it, but I should.
 
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Not once did I mention ANYTHING but clean audio signal. Not once did I mention use of power mics, supertunes, or anything to the likeness. I have specified NOTHING but 100% modulation levels and quality CLEAR audio. It is also nothing about ego or I wouldn't have mentioned modest output levels. It is about trying to find the best quality piece of equipment before I spend money on another radio.
Plain and simple, some things are built with better performance than others. I may not be able to explain the why and how, but it is quite conceivable to assume that with equal output wattage that one radio can sound louder and cleaner than another. I am simply asking, if it is possible, for a list of best to worst of radios that can perform this way. If I asked for a list of good performing SSB radios, I would get answers like "side mice 148 GTL, Uniden Grant XL, Cobra 146 GTL." Why can't one ask what is a good performing radio on AM, without the backlash of everyone assuming that everyone with a CB wants a dirty sounding splatter box? Yes, I play on AM. Yes I want a loud radio. I want a loud radio AND have it sound good at the same time. I have heard radios that sound so good that everyone steps on each other to talk to that one station, because they sound so good.

A radio can be loud and still have QUALITY audio. I have specified the desire for it in almost every post I've made on this thread. I am NOT asking what power mic to use to over-modulate. I am NOT asking who can tune 100W from a Cobra 29 (obvious exaggeration). I am NOT asking about ridiculous tunes. It is everyone else who are making such suggestions and assumptions even though I keep repeating that is not what I am looking for. Each reply I make specifies that I am NOT interested. If that is what I wanted, I would hop onto Radio"craptive" radios and ask for the most "bodacious super whackpack" they offer.

Being that I don't have to money to buy every piece of equipment out there for a comparison, I thought I would ask of other's experience.

I can only compare the radios I personally have. Currently my best is DTB tuned Uniden Grant XL, then my Johnson Messenger 4230 (though it has only been heard through a 1/2 wave dipole giving it an unfair advantage over the other mobile installs) next is my DTB tuned Cobra 29 (china made). My Uniden PC76 would beat my Cobra 29 (china made) but it is broken. My Galaxy 929 and the 95t2 sound about even(with the 95t2's V-power turned down to comparable output. Obviously the 95t2 is the biggest radio with it turned up but I am concerned with comparable outputs) but they are both next. Then my Cobra 25. Then the Uniden 510XL, and last is the Midland 1001z (which is horrible). I haven't yet hooked up my Bells reconditioned Madison to compare it, but I should.


Nobody was saying that you want all the crap you say you do not want. The discussion was simply about what sounds good in general. As far as one radio sounding better than the next most of that is not so much to do with the radio itself but with the microphone used and how well it compliments the user's own voice. that alone can make a huge difference. Some people do audio mods to their radios. All this has nothing to do with the individual radio itself but rather with what was done to that radio. The exact same radio can sound quite different with different microphones used or even with different operators. I think you would be hard pressed to get a list of best to worst as everyone has their own opinion.
 
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Nobody was saying that you want all the crap you say you do not want. The discussion was simply about what sounds good in general. As far as one radio sounding better than the next most of that is not so much to do with the radio itself but with the microphone used and how well it compliments the user's own voice. that alone can make a huge difference. Some people do audio mods to their radios. All this has nothing to do with the individual radio itself but rather with what was done to that radio. The exact same radio can sound quite different with different microphones used or even with different operators. I think you would be hard pressed to get a list of best to worst as everyone has their own opinion.

Very true. I just want to buy a new radio and don't want to be unhappy with it. I am going through a tough time and need something to be happy about but don't want to waste my money.
 
Very true. I just want to buy a new radio and don't want to be unhappy with it. I am going through a tough time and need something to be happy about but don't want to waste my money.

Quite understandable. As said the best thing to do is listen to some radios and decide what sounds best TO YOU and ask what the radio is and who did any work on it. The truth is that almost any radio can be made to sound good or awful. There are some shops that do great work but they are usually the ones NOT associated with a particular web forum as most members kiss the shop owner's ass and you won't get a reliable opinion to save your sole.
 
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You asked for input and you got input. The problem is you just didn't like what you were told.

No, not really. I was mostly getting answers to questions I wasn't asking. There is also several suggestive remarks about over-modulated junk piles, which is what I was clearly not referring to. Somehow asking about recommendations of a strong, AM, radio turns into referencing of the dirty CBer with hacked up radios. I am constantly repeating that I am seeking a radio with 100% modulation, not more. Also that the output is fairly standard of 4W carrier, not over tuned. I am simply stating that every distributor lists all their product as being loud. And they can't all be loud. It is an impossible thing for all to be loud. That would make them the same, and I' sure there are a couple that stand apart.

There was one post that seemed a little offensive to me. I don't need arrogant and inflammatory remarks for asking a question.

There are some shops that do great work but they are usually the ones NOT associated with a particular web forum as most members kiss the shop owner's ass and you won't get a reliable opinion to save your sole.

That is why I asked here. People tend to desire quality of audio more than swing watts.
 
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Quite understandable. As said the best thing to do is listen to some radios and decide what sounds best TO YOU and ask what the radio is and who did any work on it. The truth is that almost any radio can be made to sound good or awful. There are some shops that do great work but they are usually the ones NOT associated with a particular web forum as most members kiss the shop owner's ass and you won't get a reliable opinion to save your sole.

I second that. I myself spent four months getting checking out the radio I now own. I had two other radios I played with during this process. While all of this was going on(still is),I did research on different radios,found out what was out there,what was about to come on the market. There's three radios I still like to have. A Uniden 505,a Stryker 955,and a Yaesu FT-897D.
Happy hunting!
 
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