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Hey Gang
Hey Gang
My uncle gave me a 250 watt audio amplifier that he used with his entertainment system. It has an equalizer and several inputs/outputs. I know this is to boost volume for say speakers…etc but I was wondering if it could possibly make my audio a little louder if I were to hook it up to my transmitters audio inputs. Even with a mixer and a compressor / limiter I am still not getting a desired volume. It is always either to low or distorted sounding. I was just curious if this may help to boost volume going from my source to amp and then to tx.
Please let me know suggestions on this .. or if you got another idea that may work better.J.R.
Total posts : 45366Hi J.R.,
A few more details about your station will probably help us help you. Are you using AM or FM? What transmitter? What monitoring receiver?
Some part 15 transmitters will not accept high level modulation without distortion and you may be operating at the limits of your equipment. Others give great results with modest investment.
I have achieved excellent audio on both AM and FM so it can be done. I and many others here can help but as I said more information is needed.
Neil
Total posts : 45366J.R,I hope you didnt get discouraged,we are here to help! We need to know what equipment you are using and how you have it connected. Then we can guide you to a solution. Here I use a PC running Zara automation thru a 24 bit soundcard,which feeds a dj type mixer and 10 band equalizer which then feeds the EDM transmitter. Careful setting of levels yields a sound that rivals the local stations.
You can do the same with yours!
Regards,Lee
Total posts : 45366Kind of depends on the rest of your setup. But assuming this audio amp has maybe line inputs and outputs on the back or an Aux in and record out ar many other possible labels.. Yeah, you can probably use it to tinker with your audio signal and may get some results worth the bother.
Like if you aren’t currently using any eq, and you can use the eq in the amp? Heck yeah it can help a bit.
The 250 watt part of it won’t help your signal, but the audio processing parts could, depending on what hardware and software you’re running with already. Well, if you’re doing part15 FM, the 250 watt amp hooked up to some good speakers, maybe 12 inchers outdoors, and people might hear it further than your transmitter. LOL But in any case, even with a modest set of speakers it could make a very nice studio monitor.
May need to try it a few different ways and play with it a bit, but it’s likely with a bit of messing around you can find someplace it either makes your signal sound a bit better or makes hearing what you’re doing in the studio a bit more deluxe.
Even just for “goating points” it might look nice in your equipment rack/setup. Worth a try to see what it can do.
Now, if you’d like more specific advice, if you can tell a bit about your gear/chain, and maybe take a couple pics of the front and rear panel of this 250 watt audio beastie and put them up someplace folks here can take a peek? Just might get some advice rolling. Kind of hard to tell you how to hook it up when we don’t know what’s what yet, though.
Daniel
Total posts : 45366Sorry for the long delay … been a bit busy at work.. Let me see if I can explain in more detail . The amp is a RCA with 250 watts. It appears to have different output options such as Tape in/out, VCR In /OUT, TUNER, Phono…. and I believe an aux but i’m not sure. Anyway I can press a button on the front panel say tuner and then of course i will hear anything coming out of my receiver. I also hooked the big speakers that came with it and it does produce a very rich sound.
The jacks om the back of the amp are RCA Red/White Jacks … which match the rest of my audio gear setup in my studio.Now on to my station setup … I have a laptop believe it or not running Zara Radio Automation.. which I think is the best thing sense sliced bread… the audio input from my comp is going into an 8 channel mixer with the output of the mixers audio going to an Alexis compressor/limiter… then that audio is feeding into my fm transmitter which is a 100mw unit . I know thats pushing it for p 15.
Now do to my transmitter being over the legal limit a bit… I am not aiming to get anymore range out of this unite… I know the range of which it can go which is really about a block This TX is inside with an attached whip antenna that came with it . I just want my sound going into my transmitter to be a little more richer or fuller than what it is at present. That’s what I was hoping this little amp could give it a little more volume and maby make it more fuller.
So… How should I go about wiring this thing. As I said I have got audio going from my mixer to my Compressor/Limiter which has an 1/8 male plug hooked to the rear of the Compressor/Limiter which is then fed to my transmitters audio output… with RCA connectors on that end of my audio cable.
Guys I hope this makes sense.
I hope I explained this a little better. If you need more info please ask
Thanks
J.R..
Total posts : 45366J. R.,
If I follow correctly you want your modulated FM signal to have more volume. Is this what you mean by “richer”?
If perchance you have a Ramsey FM-25 or FM-30, there are two pots (one for each channel) inside which are used to adjust the audio sensitivity for the transmitter. Maybe they need to be adjusted. If yours is another brand check the manual to see if the audio is adjustable.
I use an Alesis Nanocompressor here with a FM-25 and between the Alesis’ output control and the pots I mentioned in the transmitter I get more than enough volume. I set mine so when the compressor signal lights flicker the rightmost yellow LED, I am at max. modulation. This makes it easy to check on the levels.
You should compare your signal audio level with those of commercial statons and set it about the same loudness. If you set it too high, it will probably distort and could cause interference.
Hope this hellps.
Neil
Total posts : 45366Ok, well seeing as you’re already running compression/limiting and etc, then the audio processing from the big old audio amp probably wouldn’t help much.
If you aren’t using anything for eq, that could help a bit, but small equalizers aren’t expensive if you wanted to try that, and a modern one would probably be lower noise than your 250 watt audio amp. On the other hand, the old 250 watt audio amp sounds like it’d be a very cool monitor to use to tune in your on-the-air signal.
With the distortion and the audio sound seeming too quiet, what I’d check into is the audio signal feeding into the transmitter. Anything above about 15 khz in your audio signal is pretty much wasted. Most FM receiver won’t pick it up, but the “spikes” (rapid transients) from things like high-hats and other instruments that are mostly high frequency still will trigger your limiter, causing it to reduce volume. Also they still go into your transmitter, and unless the transmitter happens to have a filter to block frequencies 15khz and above, your transmitter ends up using some of the power that could be being used for signal you can actually hear to put out those frequencies FM recievers won’t.
So some eq, whether hardware or software, might help clean up the problem. If you can patch one in (before the compressor/limiter), try cutting frequencies 15 or 16 khz and all the ones above.. and also try peeling back a bit of the extreme low end, like around 50 hz and down.
Now, does your transmitter have a circuit for “pre-emphasis” built in? If it doesn’t, you could try that, though not everybody likes the sound of it and some (like me) prefer to do that job with eq. But a standard pre-emphasis (which can be done with software before buying hardware, so you can see if it is something that helps) would be worth a try.
“Sound Solutions” will work with an older version of Zara (within some limitations) and will let you play with thinks like the 15khz clip and preemphasis and also has some really spiffy presets that might come close to a sound you like.
You can have a great source sound, a decent transmitter, and it can still take a bit of tinkering to find out what will sound good going out over the air. The #1 tool for that is ears.
I also run FM, and I thought my transmitter sounded really crappy at first until I’d tinkered with the signal a bit and found out how much level it liked and what frequencies to boost and cut a bit on the eq. Also some things that you’ll see listed as standard in some places (like pre-emphasis) may not be a sound you (or your listeners) like. Early on, I was using an eq to tame down the “boominess” a bit and cut the 15khz and up, and then tailor the frequencies in the midrange to get a nice dregree of punch and crispness. I went to using software for premphasis and it sounded ok to me, but my listeners didn’t like it as well. A couple of them said it was more “harsh” on their ears, and when I did a/b testing, they picked a bit of eq as sounding better than pre-emphasis. What I’d call “a little boomy” as a sound freak, they percieve as sounding “big”. So I went back to using just a bit of eq. Oh well. LOL
What I’m saying is it’s likely to take a bit of tinkering to find the levels and amount of compression and etc you actually like the sound of. Your audio chain can be putting out a really good sounding signal, but until you adjust it to what your transmitter puts out well, and recievers can put though a speaker good, it can sound pretty rough. But hey, if you didn’t like tinkering with knobs and settings and playlists and being finicky about the sound quality on the reciever end and all that, this hobby probably wouldn’t have appealed to you. LOL
Daniel
Total posts : 45366Another thing is if you’re transmitting stereo on FM, if the encoder is even a bit out of whack it can sound really bizarre. I messed with a software stereo encoder for a week or so and I found it to be far touchier than I was up for messing with in the long run. So I settled for having a good clear mono signal, and to heck with the little red ‘stereo’ light on the reciever. Most listeners actually don’t seem to notice at all or care that it’s in mono, and for me at least mono was a more robust signal with definitely less noise.
But again, that’s up to your tastes and ideas of what “good” is.
Daniel
Total posts : 45366Thanks Daniel and the rest of you guys for giving me ideas … I am still tinkering with it… I may get me a Small EQ and see how it does.
Daniel, you made a good suggestion about the stereo Encoder. I believe that is some of my problem .. It seems to be very touchy. The problem is how do I go about Turning the Encoder to mono? I know where the encoder is in the tx … but I cant find the Jumper? I am assuming that is what I would need to pull? By the way I am using a Veronica 100mw TX . I have had it for a couple of yrs now. For the most part the audio is clean but I have a feeling that if I could take the encoder out and just broadcast in mono that it may help my signal more. I also have premp built in .. set to 75 us. So if any of you guys could tell about how I should turn my Encoder off I would be appreciative
J.R.
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