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Set of two way speakers.

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Project by CiscoKid posted 03-28-2018 05:28 PM 1329 views 2 times favorited 11 comments Add to Favorites Watch

Something that I’ve always wanted to build is a small set of two way speakers. Woofers are ScanSpeak 15W/8530 Revelator Series. Tweeters are Hiquphon OW1. The tweeter filter is 3rd order electrical, with padding resistors on either side to carefully balance the tweeter level. The woofer filter is 2nd order electrical, with the resistor R3 used to adjust the knee slightly.

Cabinets are 3/4” Baltic birch laminated together to make 1-1/2” material. Used a lot of Titebond 3 for this. Used a Jasper circle guide to route the holes for the drivers and the ports. Finish is 6 coats of marine spar varnish. Next pair may get primed and shot with automotive enamel. The cabinets measure 15.5” tall x 9.5” wide x 15” deep and each finished speaker weighs about 30 pounds.

Initial testing shows that they sound very good, but they will sound better once on stands. They aren’t meant to rest on the floor. The bass response is startling coming from a cabinet of this size. A 2” diameter x 7” port in the rear tunes the enclosure to 43 Hz with an F3 around 39 Hz.

I’ve got $900 in materials in this project, but it was extremely fun and rewarding and something that I definitely will try again. Thank you all for looking.

-- Al, Culpeper VA





11 comments so far

View Mean_Dean's profile

Mean_Dean

6975 posts in 3597 days


#1 posted 03-28-2018 11:09 PM

Well, if they sound as good as they look, you’re going to have a sweet sounding audio system!

-- Dean -- "Don't give up the ship -- fight her 'till she sinks!" Capt James Lawrence USN

View playingwithmywood's profile

playingwithmywood

444 posts in 2047 days


#2 posted 03-29-2018 05:39 AM

I was like what 900 that is some expensive plywood and then I looked at the cost of the speakers

So why did you use plywood and not MDF ? I know MDF is nasty to work with and would not given you the natural wood finish unless you veneered them

would the be the sound difference between the two ply verse mdf if you know ?

View RPhillips's profile

RPhillips

1277 posts in 2286 days


#3 posted 03-29-2018 11:43 AM

if it’s anything like guitar cabinet construction, plywood seems to have a slightly warmer tone. but what do I know ;P

Nice job on the speakers!

...one day I too will have a nice audio system once again.

-- Rob - Indianapolis IN - Learning... one mistake at a time...

View CiscoKid's profile

CiscoKid

345 posts in 3323 days


#4 posted 03-29-2018 11:56 AM



I was like what 900 that is some expensive plywood and then I looked at the cost of the speakers

So why did you use plywood and not MDF ? I know MDF is nasty to work with and would not given you the natural wood finish unless you veneered them

would the be the sound difference between the two ply verse mdf if you know ?

- playingwithmywood

MDF is used a lot in commercial speaker building because it is inexpensive, dense, and doesn’t reverberate much. It is an easy choice when you are just going to cover it with veneer anyway. I doubled up the good plywood to try to get the same properties. I wanted heavy and dense without a lot of reverberation. All side walls are covered with 1” eggcrate foam and the rear wall is covered with 2” eggcrate foam to help tame any standing waves within the enclosure. In an ideal world speaker enclosures would be made from poured concrete, but I haven’t figured out how to pull that off yet. I don’t think there is much difference between the plywood and the MDF. If I do this again, I may make the front plate 2” thick instead of 1-1/2”. You are really looking for a very stiff and strong “springboard” for the drivers to launch from. While you cannot see it in any of the photos, I routed a very large 45 degree chamfer on the inside of the woofer hole. This is necessary when using thick front baffles to prevent “tunneling” with the woofer.

MDF was, in fact, used in this project. I used it as a sacrificial backboard when I was routing out the driver holes. I use double sided carpet tape to tape the plywood to the MDF so that everything stays in place when I complete the router cut. Otherwise, things could go south in a hurry with a rapidly spinning router bit.

-- Al, Culpeper VA

View Mainiac Matt 's profile

Mainiac Matt

9233 posts in 2778 days


#5 posted 03-29-2018 12:55 PM

Looks like a great pair of speakers… you certainly went all out with premium components.

What frequency are you crossed over at? And did you make the cross overs? Or purchase?


The tweeter filter is 3rd order electrical, with padding resistors on either side to carefully balance the tweeter level. The woofer filter is 2nd order electrical, with the resistor R3 used to adjust the knee slightly.
- CiscoKid

I wish I understood this, but sadly, my knowledge of electrical theory doesn’t go that deep.

-- Matt -- I yam what I yam and that's all what I yam

View CiscoKid's profile

CiscoKid

345 posts in 3323 days


#6 posted 03-29-2018 01:54 PM

Made the crossovers. I glued the components to scrap plywood and soldered the connections. Easiest part of the whole project. Crossovers are right under 2,500 Hz.

-- Al, Culpeper VA

View PaxJen's profile

PaxJen

70 posts in 1106 days


#7 posted 03-29-2018 05:01 PM

Very solid work! I bet they sound great. Look forward to making a set next year. I have heard some great ScanSpeak based speakers.

-- Pax - Maryland

View d38's profile

d38

129 posts in 712 days


#8 posted 03-29-2018 07:39 PM

Very nice speakers!
Agree the fronts need to be solid. I have a pair of Thiel speakers and the fronts are 1.5”, sides .75, and lots of internal bracing to keep the cabinet resonant frequency below what the speaker can produce.
When I bought that system I learned an awful lot about speakers and all audio equipment. Sounds crazy, but even different brands of interconnect wire changes the sound.

View Richard's profile

Richard

11291 posts in 3483 days


#9 posted 03-30-2018 12:05 AM

Very Nice Work & Well Done! Thanks For Posting!

Rick

-- Richard (Ontario, CANADA)

View 000's profile

000

2859 posts in 1349 days


#10 posted 04-01-2018 01:10 AM

Nice speakers and I’m sure they sound great,
I hate to break it to you but, the material is regular birch ply, not Baltic Birch.

On another note,
I wouldn’t even know where to begin with the electronic components you put together.
You did a great job, wish I could hear them.

View playingwithmywood's profile

playingwithmywood

444 posts in 2047 days


#11 posted 04-01-2018 03:23 AM



I hate to break it to you but, the material is regular birch ply, not Baltic Birch.
- Jbay

nice catch

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