Motorola HSN4018A/B Amplified External Speaker

[Sikdmax]

Can anyone tell me the wattage of this speaker? Im trying to compare its audio and volume with that of a standard 2 wire /\/\ external speaker (non amplified) and see if its worth the increased cost.

Im looking at this auction: http://cgi.ebay.com/New-Motorola-HSN-40 ... 414bd5298f

And then I see auctions that say HSN4018A like this: http://cgi.ebay.com/MOTOROLA-EXTERNAL-R ... 335a70174c

that are obviously just the 2 pin molex non 12v amplified versions. Whats going on here?


Thanks!

[Tom in D.C.]

Generally speaking (there can always be exceptions), the amplified speakers are used with equipment such as vehicle adapters for portable radios, whereas the non-amplified speakers are used with mobile radios. IIRC the amplified units used to run either six or twelve watts maximum power. Wiring diagrams are readily available; the vehicle adapter feeds a variable line-level audio signal to the external amplifier.

[escomm]

That is not an amplified speaker, you can tell when looking at the connector that it's only got 2 connectors which means there is no power running to the speaker which means it's not amplified.

As for the variable audio output ratings of various speakers (i.e. HSN4018, HSN4038 and HSN4039) Motorola accomplishes the audio output variance by varying the resistances in the speakers. IIRC the HSN4039 has 3.2 ohms of resistance and is rated at 13 watts output.

[N4KVE]

And to add insult to injury the HSN 4018 spkr is 8 ohms. A similar looking HSN 6001 speaker is 3.2 ohms & would sound quite a bit louder comparing both speakers on the same radio. So the "amplified speaker" the seller is advertising, is actually the least loud of the unamplified speakers. GARY N4KVE

[Sikdmax]

I saw some discussion here on the 6001 being a 3.2 and hooking it up to an 8ohm system would just overdrive the speaker causing greater volume, but no ill effects to the radio.

Im just trying to find a good external speaker, LOUD, to use with various projects. Figured one wanting an external 12V+ supply would automatically assume louder than non amplified, but seems like that may not necessarily be the case.

So, best option for an /\/\ 2 wire LOUD external speaker would be to search out a 6001?

[Tom in D.C.]

The entire question you raised is governed by what is known as ohm's law, which in this case would primarily involve the current capacity (output ability) of the amplifier. Now, the amplifier can be in the radio, or in the speaker case, separately mounted, it makes no difference. The 12 volts goes to the amplifier in the radio or the amplifier in the speaker and really makes no difference as to how loud the speaker is. I won't bore you with exactly how the current, voltage and resistance works in such circuits, but in general the speaker unit itself with the lowest resistance will allow the most current to flow, and to compute the power you multiply the current, which varies according to the speaker's resistance, by the voltage, which in theory never changes. That brings us back to the first sentence, above, where I said that the key to figuring the power of the speaker is determined by how much current is flowing in the circuit.

The only reason to have a speaker with a separate amplifier in it is 1.) because the amplifier in the radio may not be able to furnish enough current for your needs and/or, 2.) the speaker is located some distance from the radio or, 3.) a combination of these factors.