Help with Great Audio for my 148gtl

[tuner]

Hello,
I have been doing a bit of reading about improving my audio. I'm trying to create that nice Fat, Wide Audio I hear sometimes when I spin the dial. I'm going to be honest, I don't know a hell of a lot about electronics so you may have to "Dumb things down a little for me " lol. I have been getting a lot of help from Robb lately and he has mentioned that I should start a thread on the subject so here we go.

Before I go any further, I'm sure some of you have read Robb's thread before from a few years ago.

http://www.worldwidedx.com/threads/great-mic-sound-for-your-cb-or-export-radio-part-1.79495/

I enjoyed the read, and picked up a few things like ,

Apex 435 Condenser studio Mic with shock mount
ART Pro Tube MP preamp
2 xlr cables
1 1/4" mono cable
Cheap desk lamp scissor type

I watched a you-tube video with an operator using a stock mic to key up his radio. I mentioned this to Robb and he said to just remove the mic element wires, and install them onto the 1/4 " mono cable. So, the mic uses the xlr cable that goes into the pre amp, then out into a 1/4'" mono cable that is connected to the + &- of the stock mic.

How does it work ? It works great ! everyone has said I have nice clean audio. But it is not as wide sounding as I would like. I have since ordered a small equalizer and hope to have it soon. With that I hope to get the sound I'm looking for.I do want to say though Robb did suggest that work had to done to the tx and rx of my radio to really benefit from it. This is where I am afraid to go any further. My knowledge is lacking in this department. I really dont have any techs in my area so.....

That brings me to this question........ This is from a thread I found doing a google search for "Direct Injection Audio " Can you guys tell me if this would work out alright ? As I may give it a try

http://www.cbjunkies.com/threads/850-Direct-Injecting-Cobra-148-and-2000

Again many Thanks to Robb....

And thanks in advance to you guys

 

[mb91w126]

Yes to the DI mod, That is the one EASTSIDE is using in this thread.

http://www.worldwidedx.com/threads/...ic-with-there-radio.175424/page-2#post-498287

 

[tuner]

Yes to the DI mod, That is the one EASTSIDE is using in this thread.

http://www.worldwidedx.com/threads/...ic-with-there-radio.175424/page-2#post-498287

Thanks very much mb91w126

 

[Dipole]

If your working strictly AM with your 148 Direct injection through C174 is the way to go. However if your using the sidebands it wont work because a 148 uses a BFO chip if you try to inject at pin one of the BFO chip you will be transmitting on both upper & lower side band simultaneously. So if your gonna use SSB your need to go through the radios Modulation circuit( front mic jack). it is worth noting that te most band width you can use on SSB is about 2.7 khz wide to get the most bang for the buc keep your audio above 300htz on side band and accent the mids and highs. AM is a Different critter as you have 10khz so you can bring in the warm bottom for a warmer tone and a little reverb for fullness. Note that although it may sound as smooth as molasses on your monitor most all receiving stations are still listening on a crappy audio circuit so some of the polish will get knocked off but it will still sound better than an over modulated radio on a Noisy power mic well that is as long as you have an extremely quite environment since you have choosen a Condenser mic instead of a Dynamic carodiod.

 

[tuner]

If your working strictly AM with your 148 Direct injection through C174 is the way to go. However if your using the sidebands it wont work because a 148 uses a BFO chip if you try to inject at pin one of the BFO chip you will be transmitting on both upper & lower side band simultaneously. So if your gonna use SSB your need to go through the radios Modulation circuit( front mic jack). it is worth noting that te most band width you can use on SSB is about 2.7 khz wide to get the most bang for the buc keep your audio above 300htz on side band and accent the mids and highs. AM is a Different critter as you have 10khz so you can bring in the warm bottom for a warmer tone and a little reverb for fullness. Note that although it may sound as smooth as molasses on your monitor most all receiving stations are still listening on a crappy audio circuit so some of the polish will get knocked off but it will still sound better than an over modulated radio on a Noisy power mic well that is as long as you have an extremely quite environment since you have choosen a Condenser mic instead of a Dynamic carodiod.

Ok thank you Dipole, yes I did notice that my mic picks up a lot of background noise. Well I'm in luck I can return it and exchange. Maybe I shall try a Shure sm 58. I do like the look of my condenser though lol. Maybe I can find a dynamic mic that looks similar to the one I have now.

 

[hobie102]

Ok thank you Dipole, yes I did notice that my mic picks up a lot of background noise. Well I'm in luck I can return it and exchange. Maybe I shall try a Shure sm 58. I do like the look of my condenser though lol. Maybe I can find a dynamic mic that looks similar to the one I have now.

I am using a large diaphragm kick drum mic currently believe it or not. I have a fairly low voice and works well. Reports are FM broadcast quality audio. Pre-amp,30 band eq(not much),compress/limiter to a digitech tsr12 for a slight hint of reverb. AT-6666 Radio. Killer reports come from stations running ham style rigs like the Yaesu/Kenwood types. Reports are still great from standard cb users but you will get the best reports from the bigger radios.
I use a pair of studio phone with a mono connector soldered in to check the signal coming out of the back of the radio Using the PA function and then the talkback. Just matched the mic gain level to the factory mic to start with and went from there.
Good Luck!

 

[tuner]

I am using a large diaphragm kick drum mic currently believe it or not. I have a fairly low voice and works well. Reports are FM broadcast quality audio. Pre-amp,30 band eq(not much),compress/limiter to a digitech tsr12 for a slight hint of reverb. AT-6666 Radio. Killer reports come from stations running ham style rigs like the Yaesu/Kenwood types. Reports are still great from standard cb users but you will get the best reports from the bigger radios.
I use a pair of studio phone with a mono connector soldered in to check the signal coming out of the back of the radio Using the PA function and then the talkback. Just matched the mic gain level to the factory mic to start with and went from there.
Good Luck!

That's great man ! Thanks very much. I have a berhinger 9 band eq on the way, I'm looking forward to trying it. Did you have to modify your at 6666 to get the sound you wanted ?

 

[hobie102]

Nope. Seems to be nice and wide already. technically a 10 meter radio to begin with. If it was a cb 11 meter, yes, i would need to.

 

[tuner]

Very Nice!!