DIY 215 (rebuilding of a classic)

Syco_bass · #1 12-06-2012, 02:33 PM

Hey folks, about 6 months ago I starting getting into the notion that I would build my own bass cab. Well after searching the threads, I decided I would try to build my own 15" single driver cab. I did, and it was a gratifying experience. However, I wasn't completely satisfied. Of course, bigger is always better. So I decided to build a 2X15 cab. But wait...... It took a lot of research, time, money and time and did I mention time..... to build 1 smallish cab. This would take weeks, if not months to complete. I don't have that kind of time or the patience. So I began looking at Craigslist for a "donor" cab. Here is what I picked up for $65 at Guitar Center.

Not bad for $65. It was rated at 300W @ 4ohms. I decided that before stripping it, I would load my new 15PR400 (Faitel) drivers and decide if I would scrap the project or continue.

Here are some pics of my progress. Notice the complete lack of foam packing.

After re-stuffing, I started to load my new speakers.

I needed to cut a small piece out, but no worries, when I re-cover it, it will be covered by a new grill frame and cloth.

Here is the re-assembled cab.

After the holidays, I will strip the rat-fur off and re-tolex.
The tone of this light weight monster (62lbs with metal grill) is simply amazing. Everything is very well rounded, the lows are tight, the mids are ever so present and the highs are there and brilliant but not brittle at all. I would characterize it as "warm, ooie, gooie, chocolate Ice cream with caramel goodness"

It is everything I've always wanted/needed out of a bass cab. Did I mention it's friggin loud too.......

I'll be using this cab this weekend and shooting some live Vid footage. I might post some on Youtube when I'm done.

Stay tuned for the re-cover.

Cheers.

Rob C
Arizona Bass Company

iiipopes · #2 12-06-2012, 02:38 PM

Make sure to put a protective grill back on it.

Sundogue · #3 12-06-2012, 02:44 PM

What the internal volume of the cab and what's the tuning of it given those shelf ports?

Syco_bass · #4 12-06-2012, 02:45 PM

Quote:

Originally Posted by iiipopes

Make sure to put a protective grill back on it.

The original protective grill (expanded metal) is already back on for now.

Syco_bass · #5 12-06-2012, 02:54 PM

Quote:

Originally Posted by Sundogue

What the internal volume of the cab and what's the tuning of it given those shelf ports?

Internal volume is 6.51cu/ft (minus the volume of the speakers) I have no idea what it is tuned to, but there are 3 square ports. They each measure 3"X 9" +/- and the port shelf is 10" deep.

One interesting thing to note is that the baffle has the port holes cut out, but there is no wood extending back separating the ports. In essence, there is one large port that is 3" X 32" and the port shelf is 10 deep. Also, the port shelf tapers from 3" at the baffle and tapers down to 2" as it extends towards the back of the cab. Very interesting design.

I'm not questioning it. It sounds fantastic and is as light as I need it to be. Even using 3/4 ply for the whole box.

rpsands · #6 12-06-2012, 02:58 PM

Do the salt test!

I suspect the tuning is a bit on the high side for 5-string bass from looking at those ports and the way they slant, but it's hard to say.

Also: That box needs some more bracing. At the very minimum, a front to back in between the woofers using a 1" dowel. I'd also like to see one side to side in the same spot roughly.

Spine brace on the top/bottom would help too.

Sundogue · #7 12-06-2012, 03:01 PM

Quote:

Originally Posted by rpsands

Do the salt test!

I suspect the tuning is a bit on the high side for 4-string bass from looking at those ports and the way they slant, but it's hard to say.

Salt test. That would be the easiest to give a pretty good idea, eh?

I don't have the time to model those speakers in WinISD, but regardless, I'm sure that cab will sound great even if it's not tuned ideally.

Cool way to recycle an old cab. I dig it.

Syco_bass · #8 12-06-2012, 03:26 PM

I'll try to do a salt test this weekend. Thanks.

BogeyBass · #9 12-06-2012, 03:33 PM

Should work good.

volume around 6 to 6.5

port volume around .55

should be around 44to 49hz

most likely designed to be at 45hz

without the taper winisd shows it to be 47hz with given dimensions. real world is probably lower around 43/46hz

*edit* oppps sorry with taper most likely higher but still good.

will33 · #10 12-06-2012, 03:42 PM

+1 to the above bracing and tuning suggestions. You've got enough area there, could section off and block one port opening if need be.

Great fnd, man. Some of those SLM era Crates are Ampegs in disguise, with more budget speakers, which you've remedied nicely.

I gotta say too, I dig your Shuttle with the rack ears and headcase.....very nice. The covering looks similair to what's on my Classic400. Tweed patterned tolex/vinyl?

Syco_bass · #11 12-06-2012, 04:00 PM

Thanks for the Winsd data. What ever it is (I'll do slat test this weekend) I am hey happy with it. I think I might redo the cab in Tweed and give it a cool vintage vibe to match the head case.

rpsands · #12 12-06-2012, 04:05 PM

Yeah, you can guess that the box is probably tuned in the mid 50s with that taper...it's cutting almost a third of the port volume out. I'm going to throw a dart and say you'll come out with 55hz with the salt test

Sundogue · #13 12-06-2012, 04:15 PM

Quote:

Originally Posted by rpsands

Yeah, you can guess that the box is probably tuned in the mid 50s with that taper...it's cutting almost a third of the port volume out. I'm going to throw a dart and say you'll come out with 55hz with the salt test

Ah, cab design...

Throwing a dart and taking the results with a grain of salt.

jungleheat · #14 12-06-2012, 08:04 PM

Cool cab refurbishing. Will be interesting to see the before and after when it's finished.

astack · #15 12-07-2012, 08:19 PM

Nice! Very forgiving drivers. Good option for donor cab projects.

Make sure you don't blow it to pieces! I'd imagine might need to do a bit of rattle tracking. Hope it isn't too bad for ya.

shaginwagin · #16 12-07-2012, 10:34 PM

Sweet! Can't wait to see it finished!

Syco_bass · #17 12-08-2012, 10:01 AM

Played through this cab last night. Also had PA support. Simply amazing. Many commented on the full rich tone. I'm ordering Tolex this week. Any suggestions?

will33 · #18 12-08-2012, 10:13 AM

I'd still do the sinewave, rice/salt test, just to know what's going on with it. There's al kinds of online or phone app signal generators to use for that. Just need to rig up a speaker cable with the right plugs.

That said...if it sounds good, it is good.

I'd also set up a clean tone, and just keep tuning up gradually, watching the cones for excessive jumping, just to find the farting threshold....just to know where that line is.

Then....just play and enjoy.

Syco_bass · #19 12-08-2012, 10:31 AM

Quote:

Originally Posted by will33

I'd still do the sinewave, rice/salt test, just to know what's going on with it. There's al kinds of online or phone app signal generators to use for that. Just need to rig up a speaker cable with the right plugs.

That said...if it sounds good, it is good.

I'd also set up a clean tone, and just keep tuning up gradually, watching the cones for excessive jumping, just to find the farting threshold....just to know where that line is.

Then....just play and enjoy.

yeah, will do. I only run clean tone for the most part. I like to get a bit gritty when I dig in, but that is mostly right hand technique. No additional overdrive from pedals, etc. At sound check I pushed my amp ( using the FET channel) as far as I've ever pushed it (past 2o'clock on the pre- gain and dimed on the the master vol. And had no issues with fart out. I am very impressed and for all intent and purpose, I will never need that much volume. Our PA can carry a lot of the load if we are out doors. I'll do the salt test sometime this weekend and get back to y'all. Peace.

Syco_bass · #20 12-12-2012, 12:29 PM

Quote:

Originally Posted by BogeyBass

Should work good.

volume around 6 to 6.5

port volume around .55

should be around 44to 49hz

most likely designed to be at 45hz

without the taper winisd shows it to be 47hz with given dimensions. real world is probably lower around 43/46hz

*edit* oppps sorry with taper most likely higher but still good.

DING DING DING........

Bogeybass has it right. After running a tone gen. and salt test the salt stopped jumping and proved the cab is tuned to 44hz.

BTW, I am really digging this cab. At 63lbs including grill I can wheel this baby around on my little light duty foldable hand truck without any issues and lifting it isn't hard on my back either.

Can't wait to re-finish it, but it will have to wait till after the holidays at this point.

I'm thinking Orange tolex of some sort with a black baffle and black round waffle type speaker covers or I might even build a cloth frame style grill. I'm not looking for weight savings as much as asthetics/looks. The cab is plenty light enough for me at this point.

As far as extra cross bracing, I don't think it needs it. The cab was built using 3/4" ply and doesn't vibrate at all. I've taken it pretty high as far as volume is concerned and don't think I'll go higher/louder than what I've tested it at.

Man what a find. I highly encourage anyone looking for an old school/vintage style cab, for cheap money to snag one of these. For $65 plus the cost of two drivers, faom padding and my labor I got a really nice cab for much, much less than what a brand new one would cost.

Stay tuned for the "refinishing"...........

Peace.