Batboard

I have noticed that I have several Motorola Astro Spectra and Spectra speakers, that all have different model numbers on them. I know that the motorcycle versions have that rubber membrane under the grill, but are there other differences between the regular black/maroon blue Motorola speakers? Do they make ongoing improvements in the line, and is there a specific model number that would have superior audio quality? I've got an HSN4019A and HSN6001B in front of me, and it just peaked my curiosity.

Paul

The 4019 came with a Maxtrac plug, and the 6001 came with a Syntor/Spectra plug. You should open them up to see if they are the same cone inside.

I have accumulated many M speakers over the years. Aside from the plug differences, & the actual speaker case, the main difference is some speakers are 3.2 ohms, while others are 8 ohms. GARY

N4KVE wrote:.. the main difference is some speakers are 3.2 ohms, while others are 8 ohms. GARY

IIRC the 8-ohm speakers were made for the Maratrac line while the 3.2-ohm speakers were made for the Spectra and Astro Spectra. They're interchangeable, as the Spectra audio amp is stable down to 2 ohms, but obviously the 8-ohm speaker won't get quite as loud. Other than that they're essentially identical.

Oh, and be careful which thumbscrews you use on them.. the screws made for radio mounting are slightly larger in diameter and will jam up in a speaker if you try to force them.

motorola_otaku wrote:

N4KVE wrote:..
IIRC the 8-ohm speakers were made for the Maratrac line while the 3.2-ohm speakers were made for the Spectra and Astro Spectra.

Actually the other way around. 8 ohm is for Syntors, Spectras, and Astro Spectras. Also Micors.

4 ohm for the Maratrac, M400, and Mitrek.

3.2 ohm for the Motrac, Motran, Mocom 70 radios.

I just opened up my HSN4019B speaker. It says 2 OHM, 20 watt.

Also of interest, the PRINTED lead on the two conductor speaker wire is soldered to the negative terminal. The wire on this speaker was cut, and I had a spare wire with Spectra connector available, so I spliced them together matching the printed and non printed leads. As soon as I connected it to the radio, i got a very loud squeal! Is this thing soldered backwards?

Paul

Now it is all in shambles.

The PM1500 ships standard with an 8 ohm speaker (HSN4038). The dual control head radio ships with a 3.2 ohm speaker as the second speaker (HSN4040). Same applies to the XTL series. The "high output power" speakers are 3.2 ohms. "Standard" output speakers are 8 ohms.

I would bet a dollar that the "high output power" speakers for the CDM series (RSN4001) are the same

OK, I went through my car and home, and I have 4 speakers.....they are all the black with blue Motorola wording design....

HSN4018B 8 ohm 20 watt
HSN4019A 2 ohm 20 watt
HSN6001B 8 ohm 30 watt

So now I am very confused. On a Spectra, or Astro Spectra, what would be the BEST speaker, with the BEST audio output for them? They all work pretty well at high volume levels, but I rarely turn them up to MAX as it is. I am more concerned with which speaker specs would give me the clearest audio with the least distortion or muffledness at higher volumes. Also, what are the original products the above speakers were shipped with?

Paul

Anderegg wrote:I just opened up my HSN4019B speaker. It says 2 OHM, 20 watt.

Also of interest, the PRINTED lead on the two conductor speaker wire is soldered to the negative terminal. The wire on this speaker was cut, and I had a spare wire with Spectra connector available, so I spliced them together matching the printed and non printed leads. As soon as I connected it to the radio, i got a very loud squeal! Is this thing soldered backwards?

Paul

Soldered backwards? No. The trace lead is intended as an aid to get speakers in phase, though in general people rarely run more than one speaker on a two way radio. More likely 2 ohms is too big of a load for your radio for some reason. Use one of the 8 ohm speakers you have.

Bill, what I meant was that the lead with the PRINTING on it was actually the NEGATIVE lead. I checked one of the other Motorola speakers, and the printed lead was the POSITIVE! I guess it is a safe and easy thing to open the speaker and check this before wiring anything....only takes about 20 seconds with a power tool.

Paul

Moot point, since neither speaker lead is grounded. On most of the radios, the 8 ohm speaker comes standard, while the 3.2 ohm speaker is the optional [extra cost] high output speaker. GARY

So what is the model number for a 3.2 ohm 30 watt speaker?

Paul

I just opened up 2 HSN6001B's & they are 3.2 ohms. I also opened up 2 HSN4031A's, & they are both 8 ohms. GARY

Anderegg wrote:Bill, what I meant was that the lead with the PRINTING on it was actually the NEGATIVE lead. I checked one of the other Motorola speakers, and the printed lead was the POSITIVE! I guess it is a safe and easy thing to open the speaker and check this before wiring anything....only takes about 20 seconds with a power tool.

Paul

Paul - I knew what you meant. A little speaker 101 - polarity means nothing until you try to run several speakers. It's perfectly safe to put + to - and - to + straight from the radio to a speaker. Nothing will be damaged, and the performance will not change. It doesn't matter which side of the speaker the trace wire attaches to as long as it and it's pair are attached.

Where polarity becomes a concern is in a stereo for instance. You want the left and right speaker to be in phase so the sound is additive in free space. It's especially important for bass. If you want that bump, your speakers have to be pushing and pulling together, or you will get some degree of cancellation making it sound mushy and ill defined. You hook plus to plus and neg to neg on both sides, and crank up the tunes.

Another place it's important is public address systems for exactly the same reason - phasing. It might be mono, but if the speakers are out of phase, it can sound pretty tinny in a number of places as you move between the speakers. It's a neat phenomenon to experience - to find that one square foot area where the sound suddenly drops to nothing because the acoustic levels are the same, and the sum is near zero in your ear - all because someone wired a speaker backwards.

So, in mobile radios with one taunt speaker in a plastic box, it doesn't matter which side is plus and minus as long as they are well connected.

You are correct sir! I just tried wiring up the speaker both ways, and it worked the same both ways. I don't know why I got the squeal the first time I powered up the radio....it scared me, I thought I had done the dreaded shorting out of the audio amp thing!

And to settle the "best" question, would the HSN6001B's be the preferred speaker for the Astro/Spectra radios?

Paul

There is no best in my opinion. 8 ohms puts less of a load on the amp, but 2 ohms will get louder.

Bill_G wrote:It's especially important for bass. If you want that bump, your speakers have to be pushing and pulling together, or you will get some degree of cancellation making it sound mushy and ill defined. You hook plus to plus and neg to neg on both sides, and crank up the tunes.

Hah. You speak as if you have experience in the field.

Don't forget passive audio couplers - they don't like having input polarities reversed either. Or dual-coil subwoofers. Watching one of those fight itself because some dummy wired it wrong is amusing.