Recordable Voice Speaker Drivers

[nDAlk90 0]

I want to put a speaker by a garage area. When someone double parks or blocks the garage I want someone to be able to push a button which triggers a playback of a prerecorded message.

 

Something like:

"You have parked illegally on private property, failure to properly park your vehicle will result in a tow. This is a private parking lot, a tow truck will be called for any vehicles in violation"

 

 

Anyone know of a voice driver which can do this and power a 30Watt Speaker?

 

Thanks.

[Soundy 1]

Something like this? http://www.radioshack.com/product/index.jsp?productId=2102855#tabsetBasic

 

This 9V Recording Module stores up to 20 seconds of sound and plays it back instantly at the touch of a button. You can use the module to create a digital notepad and record reminders, to-do lists, phone numbers and more. Attach the module to a greeting card and the recipient will hear your message "live". All included components are prewired. Requires a 9V battery (not included).

 

Edit: I would expect this to be able to drive a small-ish PA horn... for something louder, try a powered horn, or add a little "kit" amplifier.

 

Re-edit: Kit amp example: http://www.rpelectronics.com/ck193-20w-bridged-power-amplifier.html

[nDAlk90 0]

I need a 30watt amp for my 30watt speaker? The mini amps I have seen are 10watt.

 

This one has an option for telephone paging though its underpowered for a 30watt speaker.

 

http://www.elkproducts.com/_webapp_2981399/ELK-800_Audio_Amplifier_module,_10_Watt

[Soundy 1]

I need a 30watt amp for my 30watt speaker?

No. Wattage rating on a speaker is the most it can handle (usually RMS, with higher, short-term peak ratings). Wattage on an amp is the most it can deliver into a specified load (usually 8 ohms for PA horns). It's a "good idea" to make sure the two are close, but unless you're planning to push the system to its limits, it's not generally critical that they match exactly.

 

The mini amps I have seen are 10watt.

Honestly, 10W is probably MORE than enough for your needs. Keep in mind that the actual output volume will vary greatly depending on the shape of the horn and the efficiency of the driver - a good, efficient driver and horn design will be louder with 10W driving it, than a poor design with 30W driving it.

[nDAlk90 0]

I should put two speakers? Or the OHM on the driver has to match the speaker?

 

It's a "good idea" to make sure the two are close, but unless you're planning to push the system to its limits, it's not generally critical that they match exactly.

[Soundy 1]

I should put two speakers? Or the OHM on the driver has to match the speaker?

 

No, and no.

 

It's not really that different than figuring out power ratings for cameras: the higher the impedance of a speaker, the less load it puts on the amp, the less current it draws, and to some degree, the lower efficiency it is... however, if the impedance is too low, then it will draw more current than the amp can supply, and you start to get distortion or possibly fried amps. So as with all other areas of electronics, everything is a balancing act.

 

Typically, an amp will list how much power it produces at a certain load impedance, as well as a range of impedances it can handle... for example, it may state it will do 20W at 8 ohms, and accept loads of anywhere from 4 to 12 ohms. With a four-ohm speaker then, at a given volume level, it would produce approximately 40W, but you'd be more likely to get distortion if you ran it at maximum levels.

 

Again, these ratings usually refer to the MAXIMUMS each component is capable of; there's nothing wrong with running well under that, and frankly, you may find you NEED to run well under that to avoid blasting out the neighbors.

[nDAlk90 0]

That's also a concern. Need to find an adjustable one with volume level. We don't want to bother the neighbors either. Any recommendation?

 

Thanks so much Soundy you are a wealth of knowledge.

 

blasting out the neighbors.

[Soundy 1]

That's also a concern. Need to find an adjustable one with volume level. We don't want to bother the neighbors either. Any recommendation?

Pretty much any audio amp you find will have SOME sort of level controls. That amp kit I linked above has adjustable output level. The Elk one you linked does as well - "The audio source is amplified up to 10 watts, adjustable from an on-board volume control."