New speakers that might be useful

[daniel_leavitt2000]

I ran into a slight problem with my first F40PH sound installation. While the sound chamber and Speaker fit in the shell, the spring prongs that are used as contacts would keep the shell from seating properly.

The solution to this was to glue the prongs down to the surface of the speaker, but I always get a bit nervous using glue anywhere near moving speaker parts.

So I decided up purchase a new inventory of speakers at Digikey. Rather than look only at performance numbers, I bought by size and contact type with preference going to soldered leads or soldering pads in that order.

Take a look at this new micro speaker I found. It's a lot smaller than the 12x8 Sobertron part I have been using for my previous projects:
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That's a PUI 12x8 wired speaker next to the Sobertron 15x11. This thing is SMALL and may make it possible to add sound to narrow hood units without any modifications to the chassis at all.

[peteski]

Can't you just cut the prongs off (trim them) to get rid of the springy part?  Then solder the wires to the remaining stubs?

Larger "cone" moves more air, so it larger speaker is usually more efficient. Of course if the smaller speaker had larger deflection range, and softer suspension, then it could match the larger speakers efficiency.

[ednadolski]

Can't you just cut the prongs off (trim them) to get rid of the springy part? 

That what I did.  The photo-etch shear cutters work well for that.

Ed

[RBrodzinsky]

I’m confused. The Soberton SP1208 speakers I use don’t have springs, just solder pads. What part number is this small speaker, and how does it sound?

[daniel_leavitt2000]

I have about a dozen different small speakers in my inventory. Though I prefer the Sobertron 12x8, there are cases where other speakers may work better. The Sobertron 12x8 have soldering pads and not springs which is why I like to use them. I have had issues with soldering onto the springs and the spring parts getting hot enough to melt parts of the speaker before, so pads or pre-wired leads are my best option.

I have not used this new speaker yet so I do not know how it will sound. It would fit into areas not normally able to fit a speaker and sound baffle. SW series fuel tanks come to mind. I was also thinking it may fit inside a rectangular tube stock from Plastruct or fit under a Loksound board on DCC compatible Atlas engines with enough room for an enclosure without having to trim the frame at all.

[RBrodzinsky]

I just looked these up (was placing a Digikey order).  These are 12x6mm speakers (not 12x8).  The frequency response curves between the PUI 12x6 and the Soberton 12x8 are very different, especially in the 500-1000Hz range, which gives us any semblance of bass

PUI 12x6
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Soberton 12x8  (note, this curve is in "free air", not with enclosure)

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[jdcolombo]

Yes, the Soberton has useful output down to about 400hz, while the PUI falls off the shelf at 1000hz.  You would get sound out of the PUI, but it would lack any kind of "body" produced by lower frequencies.

Middle C on a piano is 260hz at A=440 tuning.  An octave above that is about 520 hz.  And an octave above THAT gets you to 1040hz.  So the Soberton has a little over a full octave of range better than the PUI.  That's pretty significant.

John C.

[craigolio1]

Not sure I see those two graphs as being a fair comparison.

The top one is with 1.5v in an enclosure. The bottom one is with .8v in free air.

 Craig

[RBrodzinsky]

Not sure I see those two graphs as being a fair comparison.

The top one is with 1.5v in an enclosure. The bottom one is with .8v in free air.

 Craig

That is sort of the point. With more voltage and an enclosure, the 12x6mm is still a poorer performer than the 12x8mm. And the enclosure only improves the Soberton.

[CRL]

Ignore the frequency response graphs. Instead, mount each speaker in an appropriate enclosure, anchor the enclosure and play some source material through each speaker.

Which one sounds better?

Use that one.

Nobody listens to a frequency response graph.

[craigolio1]

That is sort of the point. With more voltage and an enclosure, the 12x6mm is still a poorer performer than the 12x8mm. And the enclosure only improves the Soberton.

Ah yes. I’m pickin’ up what you’re puttin’ down.

[peteski]

Ah yes. I’m pickin’ up what you’re puttin’ down.