"cheapowave".. continued.

This is an update on my DIY speaker project first mentioned in the econowave thread here:

http://audiokarma.org/forums/showpost.php?p=3293270&postcount=8870

with some suggestions from Zilch here which I've been pondering and basing some tweaks on.
http://audiokarma.org/forums/showpost.php?p=3296138&postcount=8879

I posted this here as I'm using some ideas from the Econowave project this is using different parts, dont want to clog up that most informative thread with stuff thats offtopic.

The woofer and comp driver were chosen without having the measurements available as they were cheap.

Assembled speakers:


Notes on construction

• 25mm mdf front baffle
• 18mm mdf sides and back
• 120 litre volume (thats 4.24 cubic feet says google)
• Pyle PDS221 compression driver
• Pyle PH612 horn
• Pioneer A30GC50 52F Q 1 woofer
• 2 internal braces
• enclosures clamped and glued with MDF wood glue only
• 2 10cm bass reflex ports

A whole pile of not always relevant snapshots of me building stuff and trying different things documented here:
http://pix.minirig.org.au/main.php?g2_itemId=1468

After working through different HF rolloff compensation schemes I have settled on a 1.1 uF capacitor with no resisistors in parallel.. although i could get the response in the high end near flat the price appeared reduced output, to the level where I would have to L-PAD the woofer to match. Since the response on the woofer isn't that linear anyway, I've gone for a tradeoff circuit:



Theres still tailoff in the high end but the results are now quite listenable:


white: pds221+ph612 no crossover, just a 33uF protection cap
black: calced total response
blue: crossover horn response
green: crossover pioneer woofer response

The crossovers have been assembled with cable ties parts and a bit of cardboard, which is now starting to get a bit ragged after all the rebuilding:


Thats two 20awg air core inductors in series I'm using for the 1.9 mH lowpass... (purchased for an earlier iteration of the crossover).

So far I'm happy with them and they are great, especially for bass heavy techno (Maurizio, Pitch Black).. but my Alesis Studio monitors still seem a bit sweeter to mein the top end..

next step.. upgrading the Comp. Drivers. to Selenium D220ti
"Upgrading to Econo?"

upgrading to econo..(wave)

My Selenium d220ti comp drivers just showed up.. so on to phase two of these speakers... replacing the Pyle PDS221 with them.. Already one thing jumps out in that the Selenium is much higher output than the Pyle.. which is why my HF compensation efforts to flatten out the curve always ended up too quiet.

Documented more of the build process for these speakers in this blog post: http://minirig.org.au/2010/01/07/cheapowave-speaker-build-mk-i/

Good stuff and the paint looks great. :thmbsp:

kfa888 said:

Good stuff and the paint looks great. :thmbsp:

Click to expand...

Thanks!

Just as an update to this I finally got around to measuring the response of them with ARTA, and documented the rest of it all in another blog post - been slow to get around to this as since they got on the official econowaver list I've just been listening to them rather than tinkering with them.

• white: calculated output
• black: measured output
• pale green: Selenium output, no crossover (33 uF protection cap)
• yellow: Pioneer woofer output, no crossover

may i ask why you used pavement paint vs regular paint? whats the benifit?

aidynphoenix said:

may i ask why you used pavement paint vs regular paint? whats the benifit?

Click to expand...

I think mainly laziness... it doesn't need any undercoat as it's designed to soak into a porous surface like concrete, and the label said it would be fine for wood as well. Also a mate used it on his P.A. speakers (with the grippy sand additive) and it came out well.
It came out with a satin, slightly textured finish that looks fine, even with my inept painting, and should be quite durable as well.