First post: Questions regarding ALTEC 612 enclosure - DIY

[GM]

I want to build this cabinet , but I am uncertain if it is good enough , since it is a mix of two...

Ideally, at least [2] drawings is required, an original for the purist and a well braced, damped variant for everybody else. At its most basic, internal and external dims will be different unless one chooses to lose some internal cab net volume [Vb] to the added bracing, material thickness to keep the original's outside dims [o.d.]. The 'standard' should have a chart of different vent dims for various tunings [Fb].

Whether either will suit the needs of your app, I can't say since you haven't given any details beyond using them for 604E drivers. Personally, unless I'm sitting on the floor, the driver is much too low to the ground for a Duplex unless the cab is tilted back, which reduces floor loading, changes the floor bounce frequency and generally just doesn't sound right to me with the HF rising up, as opposed to inline or arcing down, as normally occurs in live performances or cinema venues.

GM

[Altec Best]

You should actually use the 612C baffle since you are using a 604E.The original 612 was designed for a 515 woofer IMHO. And has a much larger port almost 3 times the size of the 612C.You can still use the baffle of the original 612 just cut the port to the 612C dimensions.Or calculate the correct size to your 604E T/S parameters and or (Cab Tuning).

@Geekstar,GM,etc... WRT the photos it is best to use a photo sharing site like Photobucket,Flickr,Image Shack.. I prefer Photobucket because it is the easiest one for me to post multiple files at once.After uploading to the site you just put a check in the box of the photos you want and scroll down to the bottom of the page and click on Actions.Box will open and then click on Generate link codes.When that box opens just click on the full size (I MG) codes.It will copy them and just paste into post..That's it.

This site has an automatic re-sizer which will shrink them a lot..So all the photos you post through Hostboard will be small.

[Geekstar]

I usually put photos on my own web server if I can't use space on a forum's own server.

I hate when photobucket, image shack etc images disappear from old posts. I thought the idea was to create a semi-permanent archive.

For example, this very thread has some rare and useful information compiled in it. It would be a shame if it disappears.

[Tralalalala]

Hi,

Thanks for the response !

Did some modifications:

1. Adjusted the front baffle so it fits the 604E?s.
2. Added 3/4 inches to the side panels. (I?m not any good at Vb and so on - If I?m off please let me know)
3. Added brackets on both sides + additional bracket between front baffle and rear panel.

Does anybody out there know the dimensions on the side brackets in the original 612C?
Should I put in the bracket that goes across the whole enclosure ( one of my first questions ) ?

I will use GPA?s crossover and will probably use a pair of monoblocked Quad 303?s as power amps.

[Alien_Shore]

Do you have the tools to determine the TS parms for your 604Es?
All you need is a signal generator and a voltmeter to do the old-fashioned way.
Something like WT2 or DATS makes things simpler.
Then you can do the math to determine your Qts and Vas, and from those two, you can get Vb.

[GM]

The original 612 was designed for a 515 woofer IMHO. And has a much larger port almost 3 times the size of the 612C.

I prefer Photobucket because it is the easiest one for me to post multiple files at once.

This site has an automatic re-sizer which will shrink them a lot..So all the photos you post through Hostboard will be small.

The original 612 is the Lansing general purpose cab for all of its 15" drivers, so predates the 515 by quite a few years and AFAIK was first used by Altec for the Duplex and Diacone series as were all the original 12-15" utility cabs.

I forgot about the different frame sizes, the drawings will need a driver cutout chart also.

Hmm, Photobucket must have made some major changes since I gave up on them due to being a pain to use and often not allowing folks to view my album without joining, so posting a test link: http://i120.photobucket.com/albums/o...Onkenwith6.jpg

Bummer, I'll just post links from now on and wish others would too since I can't see most photos in detail clearly enough.

GM

[GM]

After uploading to the site you just put a check in the box of the photos you want and scroll down to the bottom of the page and click on Actions.Box will open and then click on Generate link codes.When that box opens just click on the full size (I MG) codes.It will copy them and just paste into post..That's it.

Hmm, mine have no check box nor an 'Actions' button, instead a menu pops up on each pic, but see no way to do multiples except by generating the links and copy/pasting them one at a time.

GM

edit: See no way to enlarge the pics either, so can't read some of them.

[Tralalalala]

Hi again,

There is a cutout template on this site : Vintage Altec 15 & 16 inch Speaker Mounting Template
Is this what you think of GM when you mean a driver cutout chart ?

I do not have the tools to determine anything of TS parameters and so on... - I have just been a little bit into Vb and so on when buying a pair of very small tang band speakers I built some enclosures to.

SO: If I understand you correctly Alien_Shore this is what I should do:

1. hook up my Altec Duplex 604E?s (without enclosures of any kind) with the crossovers I?ll use and to the amplifiers I will use in the setup.
2. add a computer with a program like the DATS or WT2 as signal source - then figure out the TS parameters and so on.

Then I?ll get very exact measurements - tailored for my setup - correct ?

I?m just trying to understand - this is new for me. again: if I?m off in my assumptions please let me know.


- Tralalalala

[Tralalalala]

OK - have not read much yet, but have seen pictures of the DATS program ...
Guess that I?m wrong in my previous assumptions.

It looks like I will only need to hook up the 604E?s directly through a usb/audio cable to a computer.

My 604E?s has gone through some major surgery at GPA.
They were in a bad shape, anyway: do you think that it?s worth the effort in asking if they got these parameters on my 604E?s.

- Tralalalala

[VolvoHeretic]

I think you should stretch the height dimension to 42" tall which would give an internal volume close to 9 cu. ft. after bracing, raise the speaker closer to ear level, and nobody would ever notice you fudged the dimensions. And then of course, paint them gloss piano black.