Speaker Cabinet Construction

[Paul C]

Use the values for 1k6a012db

R1 = 25 ohms, 40w
R2 = 16 ohms, 40w
C1 = .47 uf, 200v
R3 = 8 ohms, 40w
C5 = 47 uf, 200v

R1, R2, and R3 are for the correct db correction (-12db cut) to match the PSD2002 driver to the level of the Gamma-15 woofer.

C5 and R3 are calculated from the Gamma-15's voice coil resistance and inductance (Re and Le).

Everything else as per the schematic back on the third page of this thread.

If you aren't going to be blasting these with 300 w/ch, you can just use 10w or 20w resistors. I'd use a 20w (wire wound is OK) for R3 (zobel resistor). R1 and R2, you could use 10w for living room use. You can also use a 100v electrolytic for C5, I would.

 

[jaymanaa]

Hope I'm not being to much of a PITA, but I ended up scoring a pair of Altec 511B horns with Altec 902-8B drivers on them. They are 8 ohm. I would imagine this will change some values on the cross-overs. I guess I will try them without tweeters first and add them later if needed. I never really planned out a project in my life, and I guess this one is no different. Thanks for your help (and patience) Paul. You surely have to be racking up Karma with the audio gods. Jay

 

[Paul C]

OK, here is a revised schematic, adding an L-Pad.

Here is your parts list. Since you will be using a low power amp (and these are very high efficiency drivers) in your living room, rather than megawatts in a huge theatre, you really don't need the 40 watt resistors and high voltage caps, which are expensive. You can do with 10 w resistors.

IF you notice any of the resistors getting hot, that is, hot enough to burn your finger, then go to higher wattage resistors (I highly doubt this for your usage). The way to do this is buy 4 of the 10 w resistors of the desired value and wire them series parallel to make up your 40 w resistor.

(Edited to add this) The purpose of C1 is to lift the top end response where the horn is falling off. If too hot on the top end, reduce value of C1 or even eliminate it altogether.

Here is your parts list, and your schematic will be attached.

500 Hz Crossover Parts List (for ONE speaker)

(Parts Express Part Numbers)

www.partsexpress.com

All parts 1 each per speaker except where noted

260-265 L-Pad 100 w

004-6 Resistor, 6 ohms 10 w (R1)

004-16 Resistor, 16 ohms 10w (R2)

17-8 Resistor, 8 ohms 20w (R3)

027-424 Capacitor, 6.8 uf 250v (C1) (Close enough to 6.6 uf)

027-350 Capacitor, 33 uf 100v (C2, C4) (2 per speaker)

027-360 Capacitor, 100 uf 100v (C3)

027-352 Capacitor, 47 uf 100v (C5)

266-552 Inductor, I-Core, 1.5 mH (L1)

266-558 Inductor, I-Core, 3 mH (L2)

 

[jaymanaa]

Dude, You Rock :thmbsp: :ntwrthy: I can't wait to get these going Thanks, Jay

 

[Paul C]

Post pictures!

Adjust C1, larger or smaller to affect the top end. When percussion, cymbals, etc sound right, you have it.

 

[Paul C]

So, you told your wife it was either speakers or banjo pickin'?

 

[jaymanaa]

Man, The banjo guy is scary lookin. I've seen better heads on a nickel beer. Well, the Altecs made the trip ok. Guys, I gotta tell ya, my wife ain't happy She's not officially not speaking to me, but she's not talking either. :scratch2: Hmmmm, oh well. I have to work Sat. and Sun. but plan on working on the cross-overs Monday. Just thought I'd post a couple pics to give you an idea how things are going at my love nest.

Well never mind on the pics (seems I'm over my quota) oops. Take my word for it, there large.
http://i15.photobucket.com/albums/a384/PaulCoats/const6.jpg

 

[Paul C]

"Yeah! Whoo! So what if it's as big as a Subaru and costs as much! You'll never have to trade this in. This is gonna be with you for the rest of your life. And when you die, they can bury you in it!" -- Judge Reinhold as the stereo salesman in Ruthless People.

 

[jaymanaa]

Well, I think she's even now. :sigh: She called me at noon to let me know she just signed the papers on a new GMC Envoy. Apparently my signature is no longer needed. I feel confident however that I will still receive the payment book. :tears: But hey, I'm keeping a positive attitude. :yes: Maybe it will have a Bose sound system.

 

[jaymanaa]

Damn thing does have a Bose system. Oh well.

In keeping with my time honored tradition of running everything on clip leads the first time out, I hooked up one of these for a test run. I used an old Klipsch type E crossover that I had and set it and the Altec 511B on top. I then connected the whole mess to the center channel of a Fisher KX200 that I've been using for shop tunes. The 7591 output tubes are nearly used up (the getter flash is about all gone). Anyhow, these things are incredible. I guess I'm hearing some bass frequency that wasn't here before. I can't really crank it up because the CD starts skipping at about 2 on the volume knob no matter where I try to position it with 4 foot cables. I guess I'll have to get some spikes or something :scratch2: All in all, I think the horns and tubes deal is going to be ticket for what I listen to. I'm glad that Paul incorporated an l-pad into the crossovers I'm in the process of building. The big Altecs could get a bit "honky" I think, at higher volumes, but man are they great for male voice (haven't tried any female yet). If I had to sum up my last year of searching for the ultimate system, it would be DIY (but not without the "people" who are AK).

 

[Filmboydoug]

Jay, email me a pic and I'll post ir for you. :thmbsp: I have a little room left. :yes:

 

[jaymanaa]

Here ya go. Hey, at least I color coded the clip leads. I deleted a bunch of pics, so I have some room now. This whole "Hi-Fi" deal just keeps fascinating me. I have never been exposed to high quality reproduction before. Now I can't wait to get both of these hooked up to the SET amp. I'm sure clip leads will be involved at one point or another Music is so cool, when it sounds like this

 

[Paul C]

Jay, somehow that just looks... right!

VERY cool!!!

I doubt you'd ever need more than 2-3 watts to get to the level of "Honey, would you turn that down? It's way too loud!"

"What?"

:thmbsp:


----

Aww, Jay, you lost all the construction pictures. When you can, repost those back where they were so others can see what all you did. I thought it was an excellent step by step on building these cabs.

 

[jaymanaa]

I still have them on my putor. I am going to have to figure out something for pics. Maybe a link or something? I still have a lot of stuff to build, like a linestage etc..... Then when I get all done building the ultimate bluegrass stereo, I can start on the ultimate Jimi Hendrix stereo (he's about the only other kind of music I listen to on a regular basis). I'm not sure why :scratch2: Could be mini "flashbacks" :thmbsp:

 

[Paul C]

Get a free acct at www.photobucket.com and link from there.

 

[ozmoid]

Jay, also check out http://flickr.com for the photo uploads. There are some cool tools over there, check out THIS photo with all the tube ID's. And it will automatically generate different image sizes for everything you upload. I've been very happy with the service, and most important - it's FREE!

The speakers look GREAT, Jay! And I see there is a lot to thank Mr. C for as well. Thanks, Paul, for being such a great resource at AK! :thmbsp:

-Todd

 

[Paul C]

Thanks, Todd. But now I feel responsible for Ms. Jay's new car which Jay gets to pay for. :sigh: Not to mention an impending d... uh, marital/legal difficulties.

Jay, I hope she starts talking to you soon.

But I'm real happy the speaker project is working out, really I am. :thmbsp:

Send your wife flowers, that always works for me. :yes:


Oh, Jay, for even more fun and games... I noticed you have a dog, and assume you don't have a cat. Something I would not do to a dog (love them too much for that), but if you had a cat... place his bed in the mouth of the horn, wait for it to go to sleep... then drop the needle on some good rock and roll, Brian Setzer's Guitar Slinger, for example... Yeehaw!!!!!! 0-60 in .02 seconds!

 

[jaymanaa]

It's funny that you mention the pets Paul. My dogs have a habbit of laying directly in front of the speakers when I'm playing music. When I fired up the horn setup, they both sheepishly left the room (even though the volume was quite low). I don't know if that's a good, or bad sign. I think I'll volunteer to cat-sit for the neighbor

 

[Paul C]

Jay's pics.

To continue to the end of this project, see this thread where Jay builds the crossover. Finished speaker pics are seen there.

Like this thread, Jay lost the photos, so I have reposted his photos on the last page.

So, now continue here:

http://audiokarma.org/forums/showthread.php?t=84727