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Er Dan Gill
06-15-2007, 05:42 PM
I've browsed the forums looking for an answer to this but no luck. I would love to hear from the masters here, about the different ways to mount a speaker in the hilt so that it doesn't bounce around inside. Be it MHS, sinktube, or custom. Just looking for ideas.

vortextwist
06-15-2007, 05:47 PM
I hot glued mine to the bottom of the batt pack. Mine fits pretty snug in there so it doesn't move around.

xwingband
06-15-2007, 06:45 PM
I've done that too with double sided tape.

You could also attach it to your resonance chamber if you have one. Setscrew it or again glue it in.

Novastar
06-15-2007, 08:29 PM
Generally, you want space in "front" of and "behind" your speaker. Doesn't have to be a ton.

If you can, you want some sort of... cylindrical shaped items that you can pit the speaker between... think like a black plastic film canister--you know... the ones you can store quarters in? :)

Here's the general idea.

http://thecuttingedge.s5.com/Speaker.gif

Resonance cavity length is not SUPER important, but you don't want only 0.25", and you certainly don't need 1.5"!!

I didn't do the Flange sabers exactly this way, but it's effectively the same thing...

darthdan
06-15-2007, 08:34 PM
some pill bottles work pretty good too

Novastar
06-15-2007, 08:36 PM
Exactly... that's the idea, good call!

In fact, some "extra" parts of the plastic housing from cannibalizing an MR will keep you all set with plastic cylindrical junk for at least a saber or two.

It's not good to glue it into the hilt, as if you ever need to do repairs or you wish to replace the speaker... well... it's a pain.

Jay-gon Jinn
06-16-2007, 07:36 AM
Here's what I did, same thing that Vortextwist and X-wing are talking about:
http://i119.photobucket.com/albums/o141/Jay-gon_Jinn/Arons%20training%20saber%20sound%20mods/arons-training-saber-sound-mod-7.jpg
Simple and effective, if you're not trying to fill a stage with sound! :wink:

Novastar
06-16-2007, 07:06 PM
Right Jay... that works, only problem is about 50% of your sound is "blocked".

It may be a surprise to many, but sound comes out from BOTH sides of a high-powered miniature speaker. Try mounting one "backwards" one day. $10 says you are unlikely to notice the difference.

I am not sure why this is, but it could be simply because the current is constantly being "reversed" (so-to-speak) when stuff is sent to a speaker... which is what makes it vibrate, I believe. In a nutshell. Horribly simplified. ;)

Hasid Lafre
06-16-2007, 07:25 PM
I took a section of the old MR luke casing that hd the screw still on it. then tapted it togeather so it owuld fit snug into the mhs, then for added help to keep the speaker inplace a couple dabs of hot glue.

When I can I will get a pic of it. It acts as a mount and a tiny resinance chamger

Firebird21
06-17-2007, 03:41 AM
It may be a surprise to many, but sound comes out from BOTH sides of a high-powered miniature speaker. Try mounting one "backwards" one day. $10 says you are unlikely to notice the difference.

I am not sure why this is, but it could be simply because the current is constantly being "reversed" (so-to-speak) when stuff is sent to a speaker... which is what makes it vibrate, I believe. In a nutshell. Horribly simplified. ;)


Speakers work by the alternation of current from + (positive) to - (Negative). There's 2 magnets in a speaker, one is usually a rare earth magnet (like in most cell phones and small speakers) or just very large (say, DJ equipment or a sub-woofer) and the other is an electro magnet.


When you wire up a speaker you're wiring the electromagnet. And when you play sound through it you are very rapidly changing the e-magnet polarity, as stated above. This makes the e-magnet become attracted (Hey baby!) and repelled (Get out of here dirt bag!) very, very quickly, over and over again.

The result is the e-magnet moving back and forth very quickly and with it the diaphragm (the part that you see covering the face of the speaker). This is what shakes the air molecules and produces sound. The faster this happens the higher the pitch, the slower this happens, the lower the pitch.


Some speakers need the resonance chamber to increase back pressure on the diaphragm to help control its movement and improve sound quality. Each speaker is different in this aspect, so experimentation is key.

With the speakers sold here the Bass is projected by both the front and the back side of the speaker, however the mid-high ranges are projected from the front.

More room on the back side of the speaker generally produces more low range frequencies (bass) while more room in the front will accentuate the mid-range and will help cut down on the obnoxiously loud, ear piercing highs.

Jay-gon Jinn
06-17-2007, 08:38 PM
I have the same set-up in that pic in my other RLSA hilt that I put an Anakin board I got from Vortextwist into, and that saber has a hole where the old switch used to be. There is definitely sound coming from that hole, and it also makes the saber vibrate, or hum in your hand. It's actually pretty cool.

I get what you're saying Novastar, but unfortunatly, most of my sabers' designs and construction don't really allow for more speaker vent holes near their pommels, with them having screw-on pommels. I also don't use them in a stage enviornment like you do, so I don't really need thenm to be super loud....Although I am sort of "performing" for a live audience at the charity fundraisers I costume at with the Rebel Legion and the 501st.

I am planning to do what you did to your "Flange" saber on my brass one, though, since it borrows from Flange's construction a bit! :)

Novastar
06-18-2007, 11:37 AM
I hear ya Jay... and glad you liked the "Flange" sabers, heheh.

As it is, it's funny... resonance chambers sort of (a little) go against everything most sabers designers want to avoid: WASTED SPACE! Granted, it's not really WASTED when you're using it to give a more "full" sound... but yeah... just giving up 2 to 4 inches of blank space in a saber will often feel like madness.

Personally, I try to create saber hilts that are 11" or less. This sucks giant eggs when you're trying to cram everything under the sun inside of it. But yeah... if people are making a 12" or larger hilt, everything should be just fine.

erv
06-19-2007, 01:43 AM
I'll add that something like 1" in front of the speaker is fine in general. If think I have like only 2cm in the pommel of Telum Infensus.
Space in the back of the speaker... unless you're using a MR pack or a quad square pack, you have plenty of free air and space in the hilt that makes possible the back of the speaker to resonnate in the hilt. Timbre / spectrum can be tuned using a bit of foam or cotton balls / piece of fabric. I'm using a 2+2 AA flat pack in general, and it works very fine. For Telum Infensus, I used a li-ion 7.2V stick which leaves maybe more space for the air to bounce in the hilt.
The space in front of the speaker is not really wasted for my sabers : I generally put the recharge port at the back of the pommel, so the minimum space between the speaker and the end of the pommel is just the height of the recharge port + wires (1.5 cm more or less).

Novastar
06-19-2007, 03:42 AM
I'll have to agree with you there on being creative with the resonance chamber, Erv...

As people might have seen and guessed from the Flange v3 photos, I "stacked" items as well--in other words, yes I also put the recharge port and secondary button (blaster, lockup, etc.) at the bottom of the hilt... where the soundwaves would have room to bounce all about, yet the space was still somewhat "used".

I'm not sure if I like the lockup button there at the bottom for the rear hand, or if I'd like to see one up at the choke point... I'll have to experiment.

As a matter of note, if you drill some holes in any MR saber (or "free up" some spots where grooves are underneath the T-grip sections)... you'll get a good increase in sound resonance and feel.

However... the speaker is still "scratchy" compared to the speakers I was able to hook TCSS, Plecter and Ultra up with... :)

Er Dan Gill
06-19-2007, 07:54 PM
Having the Plecter board mounted in the base of the hilt, and the speaker in the pommel, will the magnet in the speaker cause any issues with the SD card or board if they are mounted too close together? As small of a magnet as it is, I was curious if it might cause some interference issues.

Novastar
06-19-2007, 08:07 PM
Good question. I seriously doubt it, unless you are literally pressing the speaker *directly* against the SD card. Even then--that is why the SD card is shielded in plastic (think like old 3.5" floppy disks).

Back in the 5.25" days, those disks were fairly idiotic, as they were fairly easy to destroy with a magnet.

Anyhow--put about 0.25" or more of space between your speaker and the electronics and you should be good even if it WAS some awful issue.

Jay-gon Jinn
06-20-2007, 10:08 AM
Well if anyone is interested, here's how the saber I mentioned above sounds:
http://i119.photobucket.com/albums/o141/Jay-gon_Jinn/Blue%20EL%20Saber%20Conversion/th_000_0020.jpg (http://s119.photobucket.com/albums/o141/Jay-gon_Jinn/Blue%20EL%20Saber%20Conversion/?action=view&current=000_0020.flv)

djbordie
06-20-2007, 10:52 AM
so the whole film canister is a decent idea for space? or is it better to get something made frmo stronger material...

i want optimal results here, so i can pretty much make anything,
does sound resonate better in metal? or plastic? or whatever...im assuming metal because it does not absorb the sound as much as plastic...

also most optimal size? 1 inch in front and behind the speaker?

this is all going in my MHS wiht ultra sound and a 5w green

Jay-gon Jinn
06-20-2007, 12:22 PM
I would say you'd want to use a metal resonance chamber. My saber uses a 1" x 1" space in front of the speaker (inside the pommel) and then the rest of the hilt space behind it, which amounts to about 4-6 inches. The sound behind the speaker exits through an old switch hole in the hilt.

djbordie
06-20-2007, 12:34 PM
ahhh so you want sound output from the front and back of the speaker? not just the front out of the pommel?

Jay-gon Jinn
06-20-2007, 12:43 PM
Yup, having some of the sound come from behind the speaker does help, Novastar can attest to that.

Novastar
06-20-2007, 09:00 PM
yes, djbordie... you'll want to read this entire thread, as many answers abound...

Also, Jay... how funny--that sounds EXACTLY like the two sabers I created for the "Alexandra Novastar" character--Seraphim v1 and v2. Not surprisingly, they have a similar resonance chamber, and do not just shoot the sound out the "butt" of the saber, hheheh

djbordie
06-22-2007, 05:40 AM
hahahaha on another note, i just got like 50 free 1"-1.25" speakers ranging from .5w - 1.5w high quality too.

hahah i love "samples"
one company even gave me 20 for free, i hope they good

Steeljack
06-22-2007, 10:37 AM
Good question. I seriously doubt it, unless you are literally pressing the speaker *directly* against the SD card. Even then--that is why the SD card is shielded in plastic (think like old 3.5" floppy disks).

Back in the 5.25" days, those disks were fairly idiotic, as they were fairly easy to destroy with a magnet.

Anyhow--put about 0.25" or more of space between your speaker and the electronics and you should be good even if it WAS some awful issue.

Not to mention the fact that while those 5.25" and 3.5" disks stored data magnetically, the SD card stores its bits electrically, in a series of NAND flash (http://en.wikipedia.org/wiki/Flash_memory) cells. While I'm reluctant to call anything impervious to a magnetic field, flash comes close for all practical purposes.

Steeljack
06-22-2007, 11:28 AM
so the whole film canister is a decent idea for space? or is it better to get something made frmo stronger material...

I did some experimenting recently using tubes I rolled myself from a sampling of different materials: heavy laminated paper, thin aluminum sheet cut from the wall of a soda can, and polyethylene terephthalate (PETE) cut from a 2-liter soda bottle.

Of these, the PETE seemed to be the best option. The aluminum seemed to produce a slightly tinnier sound, not surprising given how thin it was. The PETE offered better bass, along with a stiffness that made it the easiest to work with and secure the speakers to.

The sections I made fit snugly inside an MHS pommel, meaning that they're approximately 1 and 3/32 of an inch in diameter. I likewise made them 1 and 3/32 of an inch high, just to be goofily consistent.

I wrote some PostScript code to produce the templates, if you can justify calling something that prints rectangles of predetermined dimensions a "template". If anyone is interested, let me know, and I'll post it.

(Edit: replaced mistaken references to HDPE (http://en.wikipedia.org/wiki/Hdpe) with references to the correct plastic, PETE. (http://en.wikipedia.org/wiki/Polyethylene_terephthalate)]

Novastar
06-24-2007, 03:49 PM
That's pretty cool Steeljack... great stuff! And yeah, duh I should have thought about mentioning the SD being electrical as opposed to magnetic, but... yup the general jist is no a speaker magnet won't affect it except by nutty anomaly.

I think it would be cool if people DID come up with some semi-scientific experiments regarding better or worse sound cavities. I remember mentioning something about this somewhere else (maybe on TF.n), but people seemed to think it was too much work for a speaker... which it just might be.

Still... my thoughts on sound are simple: if 50% of the experience is sound for your saber... why the heck would you focus the least attention upon it??

Most people focus on the light, but most of that is taken care of by the right driving and diffuser. Sound is a lot more tricky. Especially if you don't have a high-powered miniature!

ANyhow... :)