The bare cabinet is 12.44 CuFt, without the speaker and the bracing. I'm gonna be putting ports of roughly 65 sq,in in the bottom of the back panels.
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The bare cabinet is 12.44 CuFt, without the speaker and the bracing. I'm gonna be putting ports of roughly 65 sq,in in the bottom of the back panels.
Cubic inches? ........or square inches?
Pretty. Those look mighty deep, what are the dimensions? Do they fit through a doorway?
Thanks Buddy, yeah I meant square inches for the port, I'll fix the post.
Yep not a problem Volvo Heretic, 37.5 high, 30 3/4 wide, 24 deep. Insides are 35.25 high x 29.25 wide x 21 deep.
You musta took my "dream big" comment literally...:D
Go big or go home!
This is what we say when launching our power toys into the air(and other senseless maneuvers).................... right up until somebody needs an ambulance.:D
Great start! Please post your listening impressions when you conclude. Are you going to seal the backs perminently?
Nice! Those look great so far--what kind of wood is that?
2 sided Oak Ply. :)Quote:
Originally Posted by voice of the theater
I'll keep you all informed on how they sound....hoping it's good. Yes there will be backs on them with the ports cut into the lower part of it.Quote:
Originally Posted by juniper
Between you and GM I figured I better start listening to ya.Quote:
Originally Posted by Old Guy
Are you going to mail yourself to the Bahamas in that thing? ;)Quote:
Originally Posted by cradeldorf
I call that a Klipsch Cornball speaker. :DQuote:
Originally Posted by voice of the theater
BTW, Is it against the law to use that name on the forum?
There you go ! I think someone has caught the speaker bug ! The "Altec Speaker Bug" that is !!! :biggrin2: Saweeeeeet !
I won't be surprised if your new cabs (if properly tuned/ported) end up sounding way better for your 604's than the AS-101 cabs that your 604's are in now. I still think someone may have pulled 416's and 811's out of your Heath 101 cabs and stuck the 604's in there without any regard to the cabinet's size/tuning/port size being appropriate for the 604's....... Maybe that's why they sound "boxy".......
Yeah, I found out that the guy that I worked for in the graphics department at the college, His dad is the one who put them together and either sold or donated them to the college. I sent him a message about them on facebook but I haven't heard back yet. Not sure how good he was at the stuff.Quote:
Originally Posted by voice of the theater
Well, they stained up nice. I'm thinking of doing edge banding but not staining it, It should be kinda golden looking then.
Just waitin for payday to finish them up.
Those look really nice!
Wow! Gorgeous cabs for your 604's. I like it!!!!
Abe
Thank's Guys. :)
Coming along nicely ! Only a matter of time now oh and a few bucks ! :Big smile: :Thumbs up:
The edge banding is cool. What do you do that with?
Why edge banding of course.:D
Your favorite lumber yard will offer it in a variety of species. I really like the self adhesive stuff, you iron it on, fast easy and neat. But, the iron on stuff works best with well sanded edges. If you need to glue it to factory edges, probably best to get the bare stuff and use copious amounts of contact to glue it down.
Cradeldorf, those look fantastic! I really like your choice in color contrast.
Impressive work for a toilet scrubber!:D
Wow--those are beautiful cabinets--nice job!! Have you/how are you going to determine the port size/location/cabinet tuning?
Thanks Bowtie. I guess I've seen rolls of the stuff but never used it. It looks very fancy.
Thank's Guys, Yep I used the Iron on stuff went on real easy but bubbled up when I polyurethane'd it but a little heat from the heat gun and the heavy rubber roller sank it back home. Scrubbin those toilets gives me lots of time to daydream Bowtie. :) Vott I'm putting a 65 SqIn port in the bottom of the back panel That way It should do a little better job of keeping any midrange freq's from canceling out.... I hope the source knew what he was talking about. I got my port size numbers straight from the Altec "Speaker Enclosures Their Design and use" bulletin, quite a handy guide. :) I'm thinking of adding a board across the front of the baffle about 2-3 inches below the speaker hole so I can do a black cloth grill across the top and still see the wood on the bottom half. Plus it will add a little more bracing to the baffle.
~12 ft^3 with a 65"^2 vent x 3/4" tunes it to ~41 Hz, kind of high for a modern HIFI app unless a sub system is used.
GM
That's what the Altec bulletin suggested for the 604? I haven't cut the ports yet, if you got a better suggestion.Quote:
Originally Posted by GM
I'm still quite confused on this, especially after reading my Radio Shack "Advanced Speaker Design" book three times and doing all of the math long hand. Isn't the only frequency coming out of the port the box/port resonance and at Fb the speaker is motionless and all of the air motion is in the port and in faze with the woofer? Doesn't aiming the port out the rear, bouncing off of the wall make it out of faze with the woofer? :)
This is where I got my info from Volvo, otherwise I probably know less about understanding this stuff than you do.Quote:
Originally Posted by VolvoHeretic
TA Speaker Topics: Vent FAQ's
I would wait to cut the ports until you hear from GM and others here as far as their recommended size and location of the ports. I don't know much about building cabinets, but I think there's a reason that all of the Altecs I've ever seen had ports in the front of the cabinets, not in the back. Also, the page you're referencing (in your post number 30 of this thread) shows a picture of an 846A Valencia. Again, I'm far from an expert on DIY cabinets, but if that picture is any indication of the date/year of the "Altec bulletin" you're using as a reference then it's a very old reference (from the 60's) and I know that the cabinets Altec used back then were tuned much higher than later Altec cabinets like the Model 19 cabinets. I think by the later 70's Altec had a much better "handle" on cabinet tuning as far as how to get really deep bass out of a cabinet. I wouldn't use the port size that Altec recommended in the 60's if you want to get deep bass (more modern "hi fi" tuning) out of those cabinets. As I mentioned before, I'd wait and get recommendations from GM and others here (regarding port size/location) based on your exact cabinet dimensions and 604's that you're using (or in lieu of that, find a much more modern source/reference to achieve a more appropriate/modern cabinet tuning that will allow significantly deeper bass)......
That's why I asked you this question earlier in this thread. I suspect the problem you're having with the AS 101 cabinets is that they're not tuned for 604's (and someone apparently also failed in their attempt at DBR tuning with the "shelves" they installed in the cabs). I think these new cabinets will be much better for your 604's IF "appropriately" tuned/ported. You're at a crucial step right now that will "make or break" the success of this project IMHO.....Quote:
Originally Posted by voice of the theater
I think you would be astonished at how much bass my as101's make Vott. they literally shake the fillings in my teeth. :; <---see one tooth fell out already. :D . I wish Greg hung out here more....but I guess he's doing his own thing and I can respect that. I think I'm gonna split the back board so I can just replace the bottom half with a different one with a different port size in it.Quote:
Originally Posted by voice of the theater
I understand you're getting a lot of bass out of your current cabs and that you have some real issues with the sound quality you're currently getting with them--not just bass issues. I would wait a little longer to see who chimes in on this thread (hopefully GM) before you move forward--you may learn that a port in the back of the cabinet is not the way to go. I think you may learn that "out of phase" issues are a valid concern and if that is the case, that will really be bad for overall sound quality, not just bass. You may find out that the port "should" be in the front of the cab. As far as cabinet tuning/port size/location, keep in mind that this will effect the whole ratio of lower bass to mid-bass and midrange. Nothing to lose by waiting a couple of days for assistance here and in the meantime you could do a little more online research as well (i.e. possibly finding a more modern source for port/tuning calculations)......Quote:
Originally Posted by cradeldorf
Not to get too philosophical here, but I've learned the hard way that in life in general it's a very easy mistake/pattern for people to fall into (myself included) to rush when they should move slowly, and to move slowly when they should be getting their @ss in gear......
I just don't know how he calculated the 41 hz box tuning frequency? I just used this online one and came up with 29.4836? Not sure If I'm doing it right, but it looks right. Did you read the link I posted in post #32 by
John L. Murphy Physicist/Audio Engineer?
You need to be exact with the numbers to be accurate with the results. I think you said 12.44 cubic feet in an earlier post.But from that .jpg looks like you put in 12 cubic ft.IIRC you have 2 different 604's that you had GPA recone correct ? If so what did they recone them as 604 g,h, ???
He came up with the 41 Hz from your port dimensions I think.You may need to add length to the port to lower it some. 25-30 Hz port tuning is more in line for HiFi/HT I think GM was getting at.
Thank's AB I calculated my box dimensions then deducted what I calculated for all the braces plus 432 CuIn (.25 CuFt) for the speaker displacement and came up with a grand total of 12.184 CuFt of volume. so now I'll recalculate the box frequency using those numbers.Quote:
Originally Posted by Altec Best
I would be more inclined to change the size of the port per GM's recommendations as opposed to lengthening it.
I'm mulling over filling all the voids between the braces with 2" egg crate foam. I hope the 2" is the total height of the foam plus the eggs and not just the foam itself.
With those dimensions I come up with a box freq of 29.3448, there seems to be a conflict because Altec list's the cone freq. at 25 where T/s parameters put it at 27.1...... : /
I'm not sure foam is a good dampening material internally in the cabs.Good old Fiberglass insulation performs better IMO.YMMV
Maybe someone else could help out with this decision and chime in.I only ever use insulation.
I don't think I need dampening, That's only for small boxes that you want to make sound larger than they are. What I want is to break up the standing waves and keep the mid frequency waves from bounding all around the inside of the cabinet and coming out through the port or cone. Actually I think I'll try it as an sealed box first because it's just over the size where Altec reccomends an infinite baffle. I can always port them afterwards.Quote:
Originally Posted by Altec Best