Loud Audio

[Captain Kilowatt]

I gave up on this thread anyway. People overthink a simple question, never really answer it, but think they are. It is ok. I just sent out my Uniden 76 XLW for repair at Bells and I will match it with a small amp. It will sound great and be loud without distortion. He worked on my Madison and I get tons of positive reports on how good I sound. It has a good tune. It probably doesn't even put out 15W PEP, but sounds AWESOME!! I have it paired with a Turner + Three desk mic. I will toss a small class AB amp once I get my big ground plane up on the 50' tower and kick butt on the air.
I am not even bothering to ask anymore and just go with my gut on this one. That being said, I am looking for a Cobra 146 GTL and a Cobra 138 XLR for my next purchases. I am guessing that they will scream once matched with a small amp.

See, I wasn't asking about tunes, over modulation, or big watts. I just wanted some input on well built radios that are loud, not distorted and hacked. People have issues and twist my question into their rants.

Rants?? You are the one that seems to be going on the rants. Kind of just like when you first got here and immediately started living up to your screen name. Take a chill pill. This is the internet and you will get all kinds of answers some of which are indeed relevant but you don't like.My first post in this thread was

http://www.worldwidedx.com/cb-band-cb-radios/157508-loud-audio-2.html#post436047

where I addressed the belief that audio could not exceed 100% without distortion. Somewhere around that time you decided that I and/or others were trying to tell you something that you were not looking for. A few others mentioned negative peak mods and I attempted to explain how that actually worked. If all you wanted was a straight unmodded CB with a tune up then why bother asking what is the best for that? They are all pretty equal. The big difference comes in radios that are capable of being heavily modded for louder audio etc. If you had such success with Bells then why not ask HIM since he does such a wonderful job for you? He would have far more experience than anybody here.

 

[roadrage]

I really don't need a chill pill because I am not excited. Quite the opposite, actually. My reasons for my screen name are my own. It doesn't concern you, and I don't need to explain it. But that is neither here nor there. I don't wish to continue this conversation, as I stated in my last thread. It leads nowhere and I don't care to waist my time doing so. You think you know what I want answered, but it is quite obvious that you don't. Being that I did ask the question, I do know what question I want answered. I know what I am looking for. You have provided useful information, but you haven't provided what I asked. I have explained what I was looking for, as far as answers. If that doesn't satisfy you that I am not interested in what you keep explaining, than I am sorry. I have stated several times I am looking for radio comparisons, nothing more. Have you compared any radios to each other? Or do you keep telling me about modulation percentages and that you are a broadcast engineer? Than you haven't answered my request.
The ranting I am referring doesn't even concern your posts anyway, but again, that isn't something I need to explain either. I don't even care to indulge on that comment any further. I wanted to compare radios to each other and everyone wants to talk about tunes, bad tunes, and golden screwdrivers, and bitch about bad sounding spatter boxes. Those issues have been beaten dead, back to life, and dead again.
I am sorry if I have offended you in some way, but remember this is only an online forum. We don't need to be "fighting", because that is just childish. If I ask a question, feel free to answer. If I say that answer you gave doesn't answer my question, you don't have to get upset. Just take it for what it is. It shouldn't hurt your pride or your feelings at all. You certainly don't need to argue that your answer is what I am looking for whether I like it or not. I am not saying you aren't intelligent. You seem very smart. That doesn't mean that you know what I am looking for and have to get mad when tell you so. It isn't a knock at your intellectual level.

BTW, your little signature reveals much more about your personality and ego. You have an apparent need for self gratification and drive for conflict more so, than does my screen name.

 

[Nick23]

Roadrage,

I don't know if you have ever been to cbradiomagazine.com, if you haven't, be sure to take a look around there. There is one article titled "am audio monsters", definitely worth reading if you want some info on above average sounding am radios.

73
Nick

 

[Captain Kilowatt]

I really don't need a chill pill because I am not excited. Quite the opposite, actually. My reasons for my screen name are my own. It doesn't concern you, and I don't need to explain it. But that is neither here nor there. I don't wish to continue this conversation, as I stated in my last thread. It leads nowhere and I don't care to waist my time doing so. You think you know what I want answered, but it is quite obvious that you don't. Being that I did ask the question, I do know what question I want answered. I know what I am looking for. You have provided useful information, but you haven't provided what I asked. I have explained what I was looking for, as far as answers. If that doesn't satisfy you that I am not interested in what you keep explaining, than I am sorry. I have stated several times I am looking for radio comparisons, nothing more. Have you compared any radios to each other? Or do you keep telling me about modulation percentages and that you are a broadcast engineer? Than you haven't answered my request.
The ranting I am referring doesn't even concern your posts anyway, but again, that isn't something I need to explain either. I don't even care to indulge on that comment any further. I wanted to compare radios to each other and everyone wants to talk about tunes, bad tunes, and golden screwdrivers, and bitch about bad sounding spatter boxes. Those issues have been beaten dead, back to life, and dead again.
I am sorry if I have offended you in some way, but remember this is only an online forum. We don't need to be "fighting", because that is just childish. If I ask a question, feel free to answer. If I say that answer you gave doesn't answer my question, you don't have to get upset. Just take it for what it is. It shouldn't hurt your pride or your feelings at all. You certainly don't need to argue that your answer is what I am looking for whether I like it or not. I am not saying you aren't intelligent. You seem very smart. That doesn't mean that you know what I am looking for and have to get mad when tell you so. It isn't a knock at your intellectual level.

BTW, your little signature reveals much more about your personality and ego. You have an apparent need for self gratification and drive for conflict more so, than does my screen name.

My issue is that while I may not have answered your questions I was addressing a few things that came up and for some reason you decided that I was being the bad guy. While the posts I made may not have been directed at you but rather at the general content of previous posts in this thread you seemed to take it that I was speaking directly to you. Take a good look at the flow of posts and you will clearly see that. As for my signature line, watch it from time to time. It changes. If you think about the current one real good you will see it applies to ANYONE in life. EVERYBODY changes their attitude depending on who they are talking too. It is reality. There I go again.....overthinking something as simple as a signature line. :bdh:

 

[Turbo T]

Reminds me....I had a guy 10 miles from me last night tell me my audio was "blowing him away". My set up: a Uniden PC122XL, an Aststic 575-M6 mic, a 4 pill Palomar knock off amp and a 108 whip.

Then I tried him on my base rig, which is a Magnum 257HP into a TNT HD 600 amp, and an Imax 2000 antenna. He said i didn't sound near as loud.

I swear it must be in that 575-M6...

 

[Captain Kilowatt]

That may have been part of it. It may also be in part as to how the carrier to peak ratio is of either setup and whether or not either setup had any headroom left in the amp. Lots of loud radios can sound not so loud if they overdrive an amp even slightly.

 

[roadrage]

My issue is that while I may not have answered your questions I was addressing a few things that came up and for some reason you decided that I was being the bad guy. While the posts I made may not have been directed at you but rather at the general content of previous posts in this thread you seemed to take it that I was speaking directly to you. Take a good look at the flow of posts and you will clearly see that. As for my signature line, watch it from time to time. It changes. If you think about the current one real good you will see it applies to ANYONE in life. EVERYBODY changes their attitude depending on who they are talking too. It is reality. There I go again.....overthinking something as simple as a signature line. :bdh:

Look, I have a lot of respect for you. I have also learned a lot since becoming a member of this forum, some of which from you. I find many of your posts very informative and well thought out. There are a lot of bull shitters and people that think they know much more than they really do. But I feel very confident in your contributions to be accurate. If I am being defensive to assume you are talking negatively toward me when you aren't, than I will apologize to you.

 

[Captain Kilowatt]

It is what it is. I believe we have we have some straight ahead driving to do at this point. op:

 

[Turbo T]

That may have been part of it. It may also be in part as to how the carrier to peak ratio is of either setup and whether or not either setup had any headroom left in the amp. Lots of loud radios can sound not so loud if they overdrive an amp even slightly.

Good point....I found turning down the carrier made the radio scream louder. This is on a Magnum 257HP. With the knob at 9 o clock it screams loud, but not so much at 3 o clock.

And the same hold true for my Magnum S45HP I just got back today.

 

[Captain Kilowatt]

As for overall sound sometimes HOW the radio is being operated is as important or more important than WHAT is being operated.

 

[bologna_sammiges4me@yahoo]

Can any of you good folks answer 1 question for me please,
Do the new uniden pro505s have a MOSFET power transistor for its final output and if so can you specify mosfet type or ID possibly an IRF520 ?

 

[Onelasttime]

By "loud" I think what they really mean is very dynamic and punchy audio. Most of the audio giants are radio's based off of cybernet chassis designs with high level modulation and darlington style modulation circuits and plenty of audio bandwidth potential.

The export radio's have more bandwidth audio and transmit bandwidth than actual FCC type approved radio's. This is also why they become splatter boxes much more easily and why they suffer from bleed over more easily as well.

Transformer designs can be very strong on audio but the very transformer they use is also a bottleneck for audio bandwidth.

The trend today is so called "hifi" trying to approach the sound you would get on commercial AM broadcasting. This has nothing to do with loud it is about the -3db point top and bottom of the adio band width. A lot of radio's from the factory have and audio band width of around 350Hz-2800Hz and a lot of guys want to get that down to 150Hz-4500Hz or more. Some designs lend themselves to this sort of modification with less work than other's and better outcomes.

Transformer designs are a poor choice for this sort of thing. Even the NPC-RC mod's for them are very limited compared to transformerless designs. They can be very loud very easily but not hi fi with out massive redesign or direct injection and computer and rack gear so those designs are like the Cobra 25,29, Uniden PC66-78, the Road King etc.....

Your voice matters a lot as does the mic and the capacitor values in the audio chain in the radio.

Some designs are much more dynamic than other's and that is by design. Broadcast quality sound is not an efficient use of power especialy starting with a small low power package with low gain fet's and limited legal bandwidth allotted. The more you limit the audio bandwidth to what carries the most intelligible data the more efficiently you use the power you are alloted.

The closer you stay to 100% average with out pinching the negative peak and with clear intelligent speech with enough dynamics to be easy on the ear's and give sufficient articulation the better. This is especially true with a SSB radio. The more you do this the less natural your voice will sound especially if you have a lot of lows in your voice. Kind of like the VU meters on a stereo should flirt with the red part of the meter but not live there!

The most unnatural sound but fantastic use of power and bandwidth is to use some combo of phase rotation like 6,8,22 rotations and then doing any audio or rf processing and compression and expansion and limiting into the radio you can effectively double or triple the effective use of power and modulation ability of the radio at the cost of audio bandwidth. It is the opposite of hifi but it cuts like a knife through butter. The trick is doing enough to cut through more dynamic but wasteful signals with as few artifacts as possible.

The real use of hifi audio is almost entirely AM local rag chewing unless you have huge amps and a lot of broadcasting experience and equipment. A lot of those guys on the Bowel are running 10,000 watts or more. A lot of are using SDR radio's or very old vacuum tube radio's and a lot of gear!

So I think a lot of people mean "dynamic" when they say "loud". I wont touch the distortion issue that would be a long rant. Having been into audiophile gear since the 1980's and car audio in the 1990's I can honestly say that the average person has shit for ears and often thinks distorted over driven amps and speakers sound good! I am also classically trained trumpet player and builder.

Best current radio for loud punchy AM audio has to be the Stryker 955. Compared to my favorite classic President Lincoln from 1998 it will bury me on AM audio both radio's stock out of the box. No mistaking the low level modulation of my pet radio for anything else.

I think the key is to never let anyone clip a limiter out of radio unless outside processing and limiting is being done.

That and do not try to squeeze every drop of power you can from a radio. Let the radio do it's job of producing a clean nicely modulated signal and get an external amp if you need one. Get an amp that will do at least 2X the rms power you think you want and then run the amp easy. Chose a mic that fits your voice and the radio.

If you are using it as a base get an EQ for your radio they can help more than you think even on a stock radio. A parametric EQ is the best way to go if you can afford it but I do not know who currently makes one especially for CB use. If not that is fine. Electret mic is the way to go if you have a noise gate on your EQ or a quite environment. In a noisy environment a dynamic mic that you have to eat and with a mic sock is the best solution.

Modern radio's seldom need an amplified mic especially after a proper alignment. Sadly most radio's do not leave the factory properly aligned and never have.

 

[KP68]

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. 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:

Well stated sir. There is a lot to unpack on this topic so I'll keep it short. In general and in my humble opinion, the "louder" the radio the dirtier the audio and RF signal is. Like Kilowatt stated, it's not a simple matter of cranking everything up. Starting off with proper audio processing (EQing, compression/audio density, audio gain etc.) before the transmitter is key. But even after all of that things can still be screwed up in the transmitter and RF chain. I've heard myself on air while trying to push things too far and to be honest I was absolutely mortified how I sounded lol. Loud but terrible. Oh well, everybody has an oops moment. On the CB channels run 4.5kc densely packed clean audio at 100% and you will be heard. And one last thing, if you can run a carrier so big that the channel goes quiet when you key up, you don't have to be loud lol.

 

[sp5it]

Best current radio for loud punchy AM audio has to be the Stryker 955. Compared to my favorite classic President Lincoln from 1998 it will bury me on AM audio both radio's stock out of the box. No mistaking the low level modulation of my pet radio for anything else.

You are comparing 2 different AM modulation circuits/methods.
Lincoln is "low level" AM modulation ad never will sound as loud as "serial modulator" method used in 955 and may other radios. Apples vs oranges.

With 'serial modualtor" I can easily achieve 300%+ positive peaks audio without clipping. 95% negative peaks.
Mike

 

[Onelasttime]

You are comparing 2 different AM modulation circuits/methods.
Lincoln is "low level" AM modulation ad never will sound as loud as "serial modulator" method used in 955 and may other radios. Apples vs oranges.

With 'serial modualtor" I can easily achieve 300%+ positive peaks audio without clipping. 95% negative peaks.
Mike

Yes I know I even mentioned my pet radio has low level modulation and no mistaking it.

My point was that you need to start off with a radio that has the characteristics you desire.

I was pointing out the obvious difference between the different types of modulation circuits and why it matters. Serial Darlington Style Modulators, Transformer Designs, Low Level Modulation.

If you have sufficient knowledge, skill and are willing to put in the time and money you can make any radio do what you want. Clearly some designs are better starting points for some specific goals or outcomes!

I do not have enough power to do a meaningful 200%, 300% modulation and still reach out. I could tear up my local traffic but why bother? Before I would do that I would improve my antenna system. I would like a set of large beams but we routinely get winds in excess of 60mph and we get a lot of snow, freezing rain and such.

I do not think most people understand how much of your effective power get's eaten up for the sake of headroom required when you get much past 120% modulation.