New speaker cabinet.

[malsackj]

Ok Details, yes it was 12 inch speakers. Cabinet is from 1980 catalog. 4622.

JBL 4622 50 hz – 6 khz 105db SPL 800 hz crossover 422 litres 14.9 ft3


36in x 30 in x 23 1/8in

914 mm x 762 mm x 606 mm

68 lbs

two E120 and lead guitar cabinet.
http://www.lansingheritage.org/images/jbl/catalogs/1980-pro/page09.jpg

 

[Flint]

If you still want to make it a HT subwoofer, a couple of good 12 inch sub drivers and some lower tuning bu plugging one port and putting a tube on the other would get you amazing loud, low, solid bass.

 

[malsackj]

Along with the cabinet is very clean and very minor road rash. So I will be looking into this to make it my LFE possibly but to also find and get the E120 or equal for the music room allowing me to give this back as Lead Speakers. Cabinet will have different sound based on tuning and speakers for guitar work. I will measure the ports, and add some better pictures by the end of the week end.

 

[malsackj]

Looking at two of these https://www.parts-express.com/peerless-by-tymphany-ne315w-08-12-subwoofer-speaker--264-1142

 

[Flint]

If you use those two sub drivers in that cabinet (422 liters) and add ports to tune the cabinet to 19Hz, you'll get solid bass to below 20Hz - at least 112dB SPL with a 300W amp (together the speakers can take 760W peak program).

If you seal the enclosure it will be more dynamic, but have less low bass. The bass limit will be about 26Hz, which is still plenty low given room gain and perhaps a +6dB EQ boost at 25Hz.

Though large, that would be a pretty good system.

 

[Flint]

Yeah, I'd probably seal up the cabinet with two of those woofers, put some acoustic absorption on the rear and side walls of the cabinet, and get a decent sub amp with a boost in the 25Hz region.

 

[malsackj]

Yes and the two ports are 4 inch across, I plan to choose the musical side So will see about closing the ports. It appears to have some 703 thinking 1 inch.

 

[malsackj]

Here is the pictures of the empty cabinet with grill on and there is a front board to protect the grill when in transit. I did not picture this front board but it basically has the JBL logo like the side.

 

[Flint]

Yeah, you can easily plug the ports. The sheer size of this thing makes it more of an infinite baffle than a suspension loaded cab, so absolute tight sealing isn't completely necessary.

 

[malsackj]

Speakers arrive from Part-express tomorrow 13 June and work on weekend to install. If the rain stops I might have them outside for the True Audio RTA run with ports open. Need to get down into the cabinet and figure out what screws are able to thread into the T Nuts.

 

[malsackj]

Speakers have arrived. Test fitting was not good. The cutout needs to be a little bit larger, the speakers are sitting about 3/8 above the baffle. The Tnuts are 4, but the speaker has 5 bolt holes in a tire pattern so I need to get Tnuts and drill to match the speaker. Wires in the cabinet were 4 cables two black and two blue connected to speakon NL4. So I found the second pair and capped them with a wire nut. Then set up the other pair as parallel connection to two speakers, 4 ohm load the amplifier.

 

[malsackj]

expanded the hole for the first speaker by an additional 1/8 inch and the speaker dropped in. So working on second with a Dremel tool. The cutting of the grass and weeds does take up my time.

 

[Flint]

I don't think the dremel took was intended for grass and weeds.

 

[malsackj]

Think of the small version of the string trimmer. Works well but no safety guards. not a good fit for the 3 acres. however it works well around small trees and bushes to keep the string from touching the small delicate baby trees.

 

[malsackj]

So finally, speakers fit in. T nuts installed and cables attached. placed in the corner or the original sub. Sounds very good. I found that my placement needs some adjusting because when seated your in the null.
however when standing you hear the bass. 4 inch ports are plugged with a metal plate for now. With the summer heat on wife does want to limit my time outside. I have to conserve my water and heat for the 4th because I am working a church job.

Our heat index is over 100 for the week. so rest I will for the wife.

 

[Flint]

So finally, speakers fit in. T nuts installed and cables attached. placed in the corner or the original sub. Sounds very good. I found that my placement needs some adjusting because when seated your in the null.
however when standing you hear the bass. 4 inch ports a plugged with a metal plate for now. With the summer heat on wife does want to limit my time outside. I have to conserve my water and heat for the 4th because I am working a church job.

Our heat index is over 100 for the week. so rest I will for the wife.

I am excited to hear more about the performance of your new subwoofer. Got any photos?

 

[malsackj]

here is the updated photos.

 

[PaulyT]

Nice work, J!

 

[malsackj]

Thanks all, I like the 40 year old retro pro sound look. The cabinet is in fantastic almost new for being 40 years of age. I plan to have it outside around the weekend of 14, 15 July to do RTA and adjust the amp crossover.

 

[malsackj]

So its a rainy day today and I took time to RTA with pink noise the new sub. here is the result.