commercial broadcaster grade audio?

[Kamikaze]

When a tube amp is run into distortion the sound is very different from a sloid state type.

Run both at design power levels and the differences are genrally not much.

I know you don't buy into the tube thing.
But as a guitarist/musician for many, many years before I got into recording and live sound, tubes are easily detectable to my ear. No self-respecting blues guitarist that I have ever played and recorded with - including bassists - would ever use a solid state rig. In recording, the tube preamps have a definable 'phat' sound that only the real high-end/ultra expensive solid state preamps could attempt to emulate. Tubes have always sounded better - and they always will - IMO . . .

 

[Robb]

Ferrite beads - the ones I use on all audio patch cables between all rack gear and mic cable:

Ferrite Beads RFI Suppression Split Snap Beads 31 Mix

 

[eagle1911]

Just for the record, although I defended the quality of current solidstate technology nowhere did I say that I don't "buy into the tube thing" as you said Robb. I very much prefer tubes as RF amplifiers and as audio amplifiers in modulator service for commercial broadcasting as well as in my vintage 80m AM station. The reasons are more than the subtle difference in quality one sees in communications service and includes simplicity as well as the nostalgia and WOW factor. After all, real radios do indeed glow in the dark.

Harris DX-50:

50kW Solid-state PWM AM broadcast transmitter. Crazy awesome stuff.. does not glow in the dark though .

The PWM method of achieving AM is very fascinating to me. As I understand it, the DX-50 has a whole bunch of amplifier modules inside, a couple hundred I believe, all of which are class C for highest efficiency. When they are all turned on, the DX-50 produces 50kW. To produce a dead carrier, 1/3 of the PA modules are activated, all running at full power per module (each module can only run at full power by design). This gives around 16.7kW of dead carrier.

To vary the amplitude, giving AM output, the rest of the PA modules are engaged and disengaged (along with some of the modules used for the carrier alone) one by one in proportion to the input signal. This happens at very high speed, directly proportional to the audio input. So then you've got all these class C power modules turning on and off with the audio input, with less turned on at the speech valleys and more turned on at speech peaks, resulting in an amplitude-modulated final output.. this way you've got huge efficiency, and a nice clean AM sound. Fascinating stuff to me.. clear, clean AM and class C amps don't typically go together for most hams and hobbyists, but if you get fancy you can do some pretty neat stuff.

 

[Captain Kilowatt]

Harris DX-50:

50kW Solid-state PWM AM broadcast transmitter. Crazy awesome stuff.. does not glow in the dark though .

The PWM method of achieving AM is very fascinating to me. As I understand it, the DX-50 has a whole bunch of amplifier modules inside, a couple hundred I believe, all of which are class C for highest efficiency. When they are all turned on, the DX-50 produces 50kW. To produce a dead carrier, 1/3 of the PA modules are activated, all running at full power per module (each module can only run at full power by design). This gives around 16.7kW of dead carrier.

To vary the amplitude, giving AM output, the rest of the PA modules are engaged and disengaged (along with some of the modules used for the carrier alone) one by one in proportion to the input signal. This happens at very high speed, directly proportional to the audio input. So then you've got all these class C power modules turning on and off with the audio input, with less turned on at the speech valleys and more turned on at speech peaks, resulting in an amplitude-modulated final output.. this way you've got huge efficiency, and a nice clean AM sound. Fascinating stuff to me.. clear, clean AM and class C amps don't typically go together for most hams and hobbyists, but if you get fancy you can do some pretty neat stuff.

PWM-Pulse Width Modulation. Been there done that over 25 years ago when Nautel introduced the AMPFET 1 series of broadcast transmitters.Nautel is a world leader in broadcasting technology and is headquartered right here in Nova Scotia. PWM actually runs, or did run in the Nautel, class D for high efficiency. The 1000 watt transmitter, which I Beta tested for Nautel BTW, ran six modules with eight FETS each for 200 watts output. What I liked is that the TX would remain on the air with a blown module or a couple of blown modules and simply reduce power output. PWM is nice but a bit pricey. Something to look into is the new class E rigs.

The Official Class E Transmitter Web Site by WA1QIX

 

[office888]

My setup:

Behringer V63M condenser (about $60 on closeout)
Behringer UB802 mixer (About $50 on closeout)
Q-Mic arm (Ebay, ~$75)
-20 db attenuator ($15)
Misc cords & adapters ($35)

I run that all into the PHONE-IN on my FT101EE. Nothing but solid reports of crystal clear audio. I could use some more processing to increase my vocal clarity, and provide a little more punch.

Also, I use the mixer to mix the EXT SPK out on my FT101EE into my mic input, then run the headphone out to the Yaesu for PSK/RTTY

 

[eagle1911]

Not long ago I read up a little on class E stuff.. very fascinating. A class E amp is in my long term plans to build.. after I'm done with my current projects.

 

[Eastside]

I know you don't buy into the tube thing.
But as a guitarist/musician for many, many years before I got into recording and live sound, tubes are easily detectable to my ear. No self-respecting blues guitarist that I have ever played and recorded with - including bassists - would ever use a solid state rig. In recording, the tube preamps have a definable 'phat' sound that only the real high-end/ultra expensive solid state preamps could attempt to emulate. Tubes have always sounded better - and they always will - IMO . . .

Yeah....you cannot beat glass.....it has that warm tone.....I only use tube guitar amps....like to scoop the mids and tweek the bass and the treble.

You prolly also sound better if you train your voice to sound like a DJ.

 

[Robb]

You prolly also sound better if you train your voice to sound like a DJ.

You guessed it. It actually is not that hard to do, and with a little practice comes quite natural. Put a lit candle four inches away from your mouth and read a paragraph or three w/o extinguishing the candle. Breath control; as this is also practice for singing as well. Controlling air and practicing enunciating tough phrases will get to be easy before long.

". . .Yes - you too - can have an exciting new career in RADIO BROADCASTING . . ."

 

[Eastside]

You guessed it. It actually is not that hard to do, and with a little practice comes quite natural. Put a lit candle four inches away from your mouth and read a paragraph or three w/o extinguishing the candle. Breath control; as this is also practice for singing as well. Controlling air and practicing enunciating tough phrases will get to be easy before long.

". . .Yes - you too - can have an exciting new career in RADIO BROADCASTING . . ."

I am practicing right now.

Check out this guys setup.

YouTube - ‪CBRadioBB.com - CB Radio Voice Processing‬‏

 

[Captain Kilowatt]

I am practicing right now.

Check out this guys setup.

YouTube - ‪CBRadioBB.com - CB Radio Voice Processing‬‏

Anybody can make garbage and you don't need a lot of gear to do it. Honestly, that video contains audio that is far from quality and sounds as if he is just playing and making weird sounds using echo and feedback. The whole topic of this thread was about broadcast quality audio and in all honesty and by the true definition of "broadcast quality audio" you just will not get it from a CB or ham radio unless you modify the crap out of the TX IF filters to the extent that the transmitted bandwidth exceeds that allowed by law. You can make it sound really good but it will never match broadcast audio quality of 20Hz-10KHz for AM and up to 15KHz or more for FM. Perhaps I'm being picky about the definition of "broadcast quality" but having been in the business of broadcast engineering for 22 years I feel I can call a spade a spade when it comes to good audio quality.

You would be surprised how good yopu can sound with a 3KHz bandwidth with the proper processing and the knowledge to know exactly what proper is. You don't need a whole crap load of EQ and compression etc. A little will go a long way and each setup is custom according to the individual's voice. What sounds good for me may be totally unacceptable to someone else's voice. The whole thing is that wide bandwidth is NOT necessary as human voice has very little to contribute above 3KHz anyway and you should concentrate on enhancing and tailoring the audio band from 100Hz to about 3KHz unless you plan to broadcast music over the radio.

 

[Se7en]

a local here uses a small big bang tube box with W2IHY's all 3 boxs...on 11,12 AM with some superb audio.

 

[Eastside]

Anybody can make garbage and you don't need a lot of gear to do it. Honestly, that video contains audio that is far from quality and sounds as if he is just playing and making weird sounds using echo and feedback. The whole topic of this thread was about broadcast quality audio and in all honesty and by the true definition of "broadcast quality audio" you just will not get it from a CB or ham radio unless you modify the crap out of the TX IF filters to the extent that the transmitted bandwidth exceeds that allowed by law. You can make it sound really good but it will never match broadcast audio quality of 20Hz-10KHz for AM and up to 15KHz or more for FM. Perhaps I'm being picky about the definition of "broadcast quality" but having been in the business of broadcast engineering for 22 years I feel I can call a spade a spade when it comes to good audio quality.

You would be surprised how good yopu can sound with a 3KHz bandwidth with the proper processing and the knowledge to know exactly what proper is. You don't need a whole crap load of EQ and compression etc. A little will go a long way and each setup is custom according to the individual's voice. What sounds good for me may be totally unacceptable to someone else's voice. The whole thing is that wide bandwidth is NOT necessary as human voice has very little to contribute above 3KHz anyway and you should concentrate on enhancing and tailoring the audio band from 100Hz to about 3KHz unless you plan to broadcast music over the radio.

Ahhh...yeah.

I just thought it interesting that this guy is running his CB through a studio mixing board.:laugh:

 

[tecnicoloco]

Ok,let's agree on something guys:

let's try to start with a little as posible investment and if we like the results,then we can keep upgrading to a better audio processing equipment.

Like CK said you can sound pretty good with a 100Hz to 3kHz Bandwith

Joe Dirt idea is a good entry level without breaking the bank,those little Rat Shack condenser/electrec microphones sounds really good for their price,we can even build a 2 Fet (MP102) preamp properlly biased with a handfull of parts and to enhace the sound let's use a free audio software,this is just for starters,like I said above,if you like the sound and want something better then is your choice to upgrade.

What we are looking is a better tone or better dynamic range a little enhanced by external processing equipment,and also we need to learn how to make our radios to pass all that audio that we are trying to pipe truh the mic connector,Shockwave gave us some clues on how to achive a better sound out of a cobra148 chasis,Joe Dirt has some pretty good ideas,Hi Def too

We don't wat to break the bank,we just want to experience and then decide if we want to continue with Orban,Innovonics,Symetrix or whatever top of the line or mid entry level equipment we can afford.

So come guys give us a break,and steer us in the right direction




My 2 Pesos
73 de Tecnicoloco

 

[Eastside]

Well....there is always the candle voice training method....that is pretty cheap....train your voice to have that deep rich professional tone of a DJ.

 

[unit_399]

You would be surprised how good you can sound with a 3KHz bandwidth with the proper processing and the knowledge to know exactly what proper is.

Absolutely right, Cap'n KW. And this can be done without spending a ton of money.

- 399