So i recently saw a pair of these boxes for sale on eBay. They were advertised as having 10" speakers, and I liked the shape of the units - thought they might come in for portable boomboxes or a decent small PA system. I paid £25 for the pair - I couldnt even buy the wood for that.
So I collected them had a look inside. The speakers are actually Eminence ME12-2008, which a quick Google leads me to believe are precursors to the Deltas. Quite what these speakers were built to be i'm not sure, but I want to make them full range.
So my question is, what's a commonly available crossover/tweeter combination that I can throw in here to make them full range?
So I collected them had a look inside. The speakers are actually Eminence ME12-2008, which a quick Google leads me to believe are precursors to the Deltas. Quite what these speakers were built to be i'm not sure, but I want to make them full range.
So my question is, what's a commonly available crossover/tweeter combination that I can throw in here to make them full range?
Nice find. These might have been used for guitar amplification. Do the cabinets have ports?
You could Econowave them, if that is a verb.😉 This assumes that they will not be supported by subwoofers, otherwise the compression drivers cannot keep up, because they are crossed over at a relatively low frequency.
Eminence ME12-2008 woofers should be 12".
You could Econowave them, if that is a verb.😉 This assumes that they will not be supported by subwoofers, otherwise the compression drivers cannot keep up, because they are crossed over at a relatively low frequency.
Eminence ME12-2008 woofers should be 12".
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I suggest you use an Eminence compression tweeter and high pass crossover as linked to below:
APT:80 - Supertweeters | Eminence Speaker
PXB:3k5 - Crossovers | Eminence Speaker
APT:80 - Supertweeters | Eminence Speaker
PXB:3k5 - Crossovers | Eminence Speaker
Looks like it was intended for guitar/bass use.
I've used the 10" version, and it's not bad. Rolls off quite smoothly (no obvious nasties) towards the kHz range.
I'd grab a 1" exit compression driver on the biggest horn that'll fit on the baffle, and cross around 2kHz.
Chris
I've used the 10" version, and it's not bad. Rolls off quite smoothly (no obvious nasties) towards the kHz range.
I'd grab a 1" exit compression driver on the biggest horn that'll fit on the baffle, and cross around 2kHz.
Chris
Hiya TBTL!
Yes, they are 12", and no, there are no ports in there. Just a heavy duty sealed box with the speaker wired directly to a jack socket.
What's this Econowave magic that you speak of? 🙂
Yes, they are 12", and no, there are no ports in there. Just a heavy duty sealed box with the speaker wired directly to a jack socket.
What's this Econowave magic that you speak of? 🙂
I think considering I paid £25 for them ($30?), adding another $170 in parts wouldn't really make sense at this point 🙂 Although I will look at those links - thankyou!
There is a product suited to your budget. Goldwood GT-520 1" Soft Dome Horn Tweeter. Costs $12.50 at PE. Filter made of 2 npe caps, one inductor and possibly 1 resistor would cost you 6.5 $/piece. These values are to be found by measurements or at least simulations based on factory provided graphs.
Or perhaps an even more extreme solution, a Goldwood GT-1005 Wide Dispersion Piezo Tweeter, selling for $ 2.47/piece.
If you can, try finding original Motorola piezo tweeters instead.
Surely, I would try piezo's first.
how about this Leson piezo? - they have built in step-up coils so are >100dB sensitive at "1 watt" - I'm not sure how crossovers are handled
Leson TLX2 tweeter 200w (Pair) | eBay
Leson TLX2 tweeter 200w (Pair) | eBay
An Econowave speaker is an old hi-fi speaker with a 10" or 12" woofer, of which the mid / high section is replaced by a constant directivity waveguide + compression driver + passive crossover. It costs around USD $90 for each speaker, so unfortunately it is not an option for you.
Link 1
Link 2
Link 3
As the idea is designed for a hi-fi application, the compression driver is crossed at a somewhat low frequency and cannot handle much abuse.
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Here is a UK source of inexpensive piezo tweeters:
PA tweeters and horn tweeters
Check the dimensions to see which ones would fit the available space in your cabinet.
If you do decide to go for a piezo tweeter, then check out the very sensible crossover suggestions in this link:
Frugal-phile | Piezo Tweeter Crossovers | J Risch
Okay, so I got a couple of the cheap tweeters on order, and looking at that xover page I need a 22ohm resistor and a 1.5uf cap on each.
What sort of voltage/wattage ratings should I be looking for?
What sort of voltage/wattage ratings should I be looking for?
Thanks for that 🙂 Limited to eBay at the moment - what about these particular items?
Bipolar Electrolytic Capacitor, 1.5 uF, 250 V - VISATON | eBay
2x AX20W-22R Resistor wire-wound ceramic case THT 22Ω 20W +-5% PRW020JW220B00 7429503267285 | eBay
Jim
Bipolar Electrolytic Capacitor, 1.5 uF, 250 V - VISATON | eBay
2x AX20W-22R Resistor wire-wound ceramic case THT 22Ω 20W +-5% PRW020JW220B00 7429503267285 | eBay
Jim
those Leson are good quality (mine were better than CTS KSN1005 and 1016) plus are sensitive enough for horn systems due to the built in impedance matching coil..
Here's some Goldwood 1005 copies I measured. There are far worse than these available.
Brian Steele came up with a pretty good inexpensive "Frankenpiezo" mating GRS to Goldwood parts - but only for the rectangular 1016 horn.
Here's some Goldwood 1005 copies I measured. There are far worse than these available.
Brian Steele came up with a pretty good inexpensive "Frankenpiezo" mating GRS to Goldwood parts - but only for the rectangular 1016 horn.
Please do.
If the tweeter turns out to be too loud then the Frugal-phile link gives a simple solution:
Add[FONT=Verdana, Helvetica, Arial] a[/FONT][FONT=Verdana, Helvetica, Arial] film cap of about 0.15uF in series with the piezo [/FONT][FONT=Verdana, Helvetica, Arial]for 6 dB of attenuation.[/FONT]
[FONT=Verdana, Helvetica, Arial]This cap is placed in series with the piezo, but to the right of the 22[/FONT][FONT=Verdana, Helvetica, Arial]Ω resistor shown in the diagram. [/FONT]
If the tweeter turns out to be too loud then the Frugal-phile link gives a simple solution:
Add[FONT=Verdana, Helvetica, Arial] a[/FONT][FONT=Verdana, Helvetica, Arial] film cap of about 0.15uF in series with the piezo [/FONT][FONT=Verdana, Helvetica, Arial]for 6 dB of attenuation.[/FONT]
[FONT=Verdana, Helvetica, Arial]This cap is placed in series with the piezo, but to the right of the 22[/FONT][FONT=Verdana, Helvetica, Arial]Ω resistor shown in the diagram. [/FONT]
Parts are on order so just a waiting game now. I'm sure the tweeters will fit in the cabinets but just thinking - would mounting them in their own little enclosure up on a pole be a good idea for more effective dispersion?
Those piezos are just going to add a little high end sparkle.
Pole mounting involves having a woofer enclosure on the floor and a midrange/high frequency enclosure up on the pole - not simply a tweeter.
It would cost a lot more to make a pole mounting arrangement which is effective.
Pole mounting involves having a woofer enclosure on the floor and a midrange/high frequency enclosure up on the pole - not simply a tweeter.
It would cost a lot more to make a pole mounting arrangement which is effective.