Peerless 830657 for <$6a piece!

[PWR RYD]

The driver reminds me a lot of this old buyout:

http://www.parts-express.com/peerles...4-ohm--299-250

I have 4 of those buyouts sitting on my shelf waiting to build a killer MTM garage set of speakers with a cheap CD and waveguide I bought from PE for peanuts.

[donradick]

It looks to me that there are still 13 pairs available at this moment. You have to change the "Package Quantity" from 1 to 2 to see the $15 deal on the pair.
I just received mine, these are really nice looking.

When you get a chance, could you burn in a few and grab the T/S params if you're able?
I won't get mine until 7/21

[donradick]

The driver reminds me a lot of this old buyout:

http://www.parts-express.com/peerles...4-ohm--299-250

I have 4 of those buyouts sitting on my shelf waiting to build a killer MTM garage set of speakers with a cheap CD and waveguide I bought from PE for peanuts.

They look the same, but the posted T/S for these is quite a bit different.
Makes me think this was special run for a particular manufacturer.

re: tweeter
Yah, now I"ve got to find a tweeter that can play low with 96 dB efficiency. ;-)

[dankwijoti]

When you get a chance, could you burn in a few and grab the T/S params if you're able?
I won't get mine until 7/21

Sorry, I don't have a woofer tester. However, I hooked up my el cheapo LCR meter to 2 of them right out of the box and found: Le 1.089 mH and Re: 7.7 ohms for each. A bit baffling, really. Would either drop with a few hours burn in?

[dankwijoti]

re: tweeter
Yah, now I've got to find a tweeter that can play low with 96 dB efficiency. ;-)

I'm hoping I can make something fun with the old BC25SC06. I have a couple sitting in an unused pair of "hotrodded" B652s.

[kenny_k]

dankwijoti, thanks.

[Chris Roemer]

Yup. My NS6 drivers measured 0.68 w/an Fs of 65.

[donradick]

Yup. Mine measured 0.68 w/an Fs of 65.

Wow, that's pretty much identical to the old Aura NS6 drivers. Maybe an aperiodic vent (Stents) is the way to go.
Does an aperiodic vent minimize excursion? Xmax is the problem I'm seeing in a Unibox sim.

[JavadS]

These are tempting but they model is a very large enclosure, no? Was imagining running 3 or 4 per side but it's a very big airspace. Javad

[PWR RYD]

They look the same, but the posted T/S for these is quite a bit different.
Makes me think this was special run for a particular manufacturer.

re: tweeter
Yah, now I&quot;ve got to find a tweeter that can play low with 96 dB efficiency. ;-)

Well yes, clearly this is an 8 ohm driver and the NLA buyout I mentioned was a 4 ohm driver. But the frames, cone, surround, and magnet look to be at least very similar.

[PWR RYD]

They look the same, but the posted T/S for these is quite a bit different.
Makes me think this was special run for a particular manufacturer.

re: tweeter
Yah, now I&quot;ve got to find a tweeter that can play low with 96 dB efficiency. ;-)

How about this CD in a Dayton 12 x 6 horn?
http://www.parts-express.com/peerles...ny-dfm-2535r00

[donradick]

How about this CD in a Dayton 12 x 6 horn?
http://www.parts-express.com/peerles...ny-dfm-2535r00

The efficiency sure is good! Not sure I'm ready for (my first) horn design.
I'll know much more once I grab the T/S specs.

[dankwijoti]

Does an aperiodic vent minimize excursion? Xmax is the problem I'm seeing in a Unibox sim.

Aperiodic designs would limit excursion, I would think. The Sten design calls for a single 3/8" hole per chamber, basically just lowering the Q of the box. Essentially you are just making the box leakier without introducing Helmholtz resonances in the holes you make. The closer to sealed (the less leaky), the more limited the cone excursion would be, right?

[donradick]

I spent some time in Unibox last night (of course all of this depends on accurate (and consistent) T/S params) - and found that driver excursion was
definitely the limiting factor. Found some old Internet discussions about AP vents, so I now knew how to munge the parameters.
A standard closed box model was ugly, with massive over excursion below about 100 Hz. Changing Ql on a closed box to 2 or 3 caused the
excursion curve to flatten a bit, but it was still over xmax below 100 Hz.
Preliminary model that looks best is vented, with a somewhat smallish box that's tuned a bit high.
We'll have an indepth discussion later, but I think that floor reinforcement and boundary reinforcement will flatten out the overall response
to a nice solid bass capability.
I"m not an expert at some of the modeling, but using Boundary Modeler reinforcement added to the Unibox FRD looks like F3 about 50Hz, and
F6 about 40 Hz. TBD later.

[JavadS]

I found the same Don, a port tuned in the 60-80hz range performed best, tuning of 40hz required a massive box to make it work, like over 28l per driver minimum, more like double that. I don't see 4 of these things outperforming 2 decent 8" in a smaller enclosure for example 2 RS225 in 60l ported puts out a lot of nice bass to 30hz. But these things are cheap. Javad