Bad Audio Quality when attached to speaker amp

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gr8tff

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Folks,

I was testing the SDS200 in place of our 996p2's attached to the station alerting system at our stations. When attaching it to the amp, the normally good audio quality from the SDS200 sounds muffled and not good at all compared to the older scanners or a Unication. Does anyone have any suggestions or have any proven remedies?


Any help is appreciated


Thanks
 

ofd8001

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I don't have an SDS 200, but other mobile models have both headphone and a line out jacks. Line out is what to choose. Have you done the "treatment" for the hum? Another thought is there may be something close to the SDS 200 that is more susceptible to hum/interference than other things you have used.

Less likely is a cable issue, especially if this is the same cable used for those other radios.
 

MisterLongwire

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Your problem is that you are using an amplified speaker. I am using an MFJ speaker with my SDS200 and all is well.....sweet audio...no hum...just pure audio...No need to use an amplified on your 200. On handhelds yes, even on my HP2
 

byndhlptom

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I believe that most of the newer scanners are using bridged amplifiers for the speaker. This requires that the speaker leads must NOT be tied to a system or audio ground. There have been several threads discussing this....

I suspect that you are shorting the radio audio amp when you tie it to a grounded system. A ground isolating transformer will probably be needed

$.02
 

MisterLongwire

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Per THE MANUAL...IF ONE CAN READ...IT SAYS:"CONNECTING AN EXTENSION SPEAKER In a noisy area, an optional amplified extension speaker, positioned in the right place, might provide more comfortable listening. Plug the speaker cables 1/8-inch (3.5-mm) mini-plug into your scanners back-panel Ext. Sp. Jack. Warning! If you connect an external speaker to the scanner’s Ext. SP jack or headphone jack, never connect the audio output line to a power supply and ground. This might also damage the scanner. All audio output is Class-D amplified (PWM). Never connect Ext. SP jack or headphone jack to an external Class-D AMP .....So, as I said, my speaker is hooked up to the back. It is not amplified. If you want to use an amplified speaker read instructions on where to put the speaker plug in
 

Ubbe

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Don't know about the 996 but 536 and probably SDS200 uses a stereo amplifier. One channel to speaker and the other to the earphone jack. If you use an amplified speaker they usually do not have any ground to the mains as the power supply will work as an isolator but a ground loop isolator are needed for most other applications, like connecting to a computer or some sort of external audio electronics. Most professional made devices that handles audio use a transformer, that sometimes can be configured by jumpers to either work as an unbalanced grounded system or "floating" balanced mode the same way as a ground loop isolator works. So it might be a good idea to look in the alerting systems audio input if there's some kind of configuration settings available, or just buy that $10 ground loop isolator.

/Ubbe
 

TailGator911

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I just set up an external BC20 speaker to my SDS200 and that audio is sweet, nice and rich and clear. First time in a very long time I've paired a Uniden scanner with a Uniden speaker, working like a charm. They sound great together.
 

seth21w

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I am looking for a speaker to hook to my sds200 to finish eliminating the electrical hum I have the bc7 speaker but I was reading about the bc20 noise reduction and the Bose amplifier speakers you have there I have the part installed nmp200 but still slight noise will either of these eliminate the noise using the back 3.5mm jack?
 
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