JGR's rock CAB of destruction is complete!!!!!

[JGR]

So..... I figured I would see if I could build a cab to go with my preamp. My main cabs are the three Berg NV's and the Bag End S15D stack. I lean towards a sealed, punchy vibe, and I like some breakup on the top end - I tend to play on the louder side, so I've become used to the compression and grind that comes from pushing things a bit. I don't want fuzz or wooly distortion, just a bit of edge/crunch/harmonic richness in the upper mids and treble. I've gotten some great tones running biamped with the top end going into a guitar cab - certainly nothing new, a lot of folks have done it and seem to dig these types of tones. Kind of in the same vein of the folks who like the top end of the vintage SVT cabs. I've spent a lot of time tweaking and experimenting over the years and have a very good understanding of how each piece of my rig contributes - the strings, pickup/height, amp, cabs - and volume. For me, the speakers contribute to the tone, so while I am not looking for something totally skewed in response, I am not looking for totally flat/accurate either. I just want something balanced and musical, so that's what I set out to build - something that can handle massive power, but that also gets the nice top end at less that "war" volume. My favorite cab is the Berg NV412 as a point of reference. I wanted a cab with a tight, clean low end and a warm, harmonically rich top end.

So I've been mixing speakers like Reese's chocolate and peanut butter to get the best of both worlds. I went through several mids and crossover designs until I got it right. To me, it sounds natural and balanced, like one big speaker, and sounds like I want it with my peamp flat. It sounds great on bass, but I think what is more impressive is that it also sounds killer on guitar. I haven't seen any cabs that can pull that off. I have a couple of Marshall Mode 4 4x12's with V30's and a pair of Mesa Recto 2x12's loaded with EV's which are my favorite. This cab sounds a lot like my EV cabs with a bit more crunch like the V30's (but smoother), and a much bigger low end.

I built the cab with 1/2" BB with a 3/4" baffle; the baffle is dadoed into the shell and the sides and back are all rabbeted. It's extremely well braced. Given the custom mid I ended up going with weighs as much as the 15, the finished weight isn't bad at 57 lbs. Form factor makes it easy to schlep. The cab is displacement limited to 500 watts and has a response of ~46Hz - 6kHz (-10dB).

Here's a video I just shot with it on bass and guitar - the bass came through pretty well, but the high gain is a bit bright and compressed - high gain guitar is certainly more sensitive to camera placement - take my word for it, it sounds killer in person.

Running the Fractal Audio Axe FXII with bass AND guitar through the cab
http://youtu.be/SEenNJUKpvs

Here's some other disjointed clips:

Just bass and the Axe FX
http://youtu.be/aIRe7Oelbto

JGR preamp clean, dirty, and in-between
http://youtu.be/zaz2lekoaJw

[5StringPocket]

That's a nice clean build. Care to share any details about the drivers and crossover point?

[1n3]

Originally Posted by 5StringPocket

That's a nice clean build. Care to share any details about the drivers and crossover point?

Ditto. Also interested in your striping technique on the sides.

[nitromullet]

Very nice! Looks and sounds great!

[3rdcurve]

Originally Posted by 5StringPocket

That's a nice clean build. Care to share any details about the drivers and crossover point?

+1

Amazed at how great it sounds with a guitar. What kind of sensitivity are you at with the cab?

[christw]

Wow, that thing sounds incredible! Like usual, I enjoy your taste sir!

[JGR]

Originally Posted by 5StringPocket

That's a nice clean build. Care to share any details about the drivers and crossover point?

Thanks. I'll reiterate what the smart folks here have been telling all us along - that the crossover is critical and needs to be matched to the specific drivers being used. I wouldn't bother with an off the shelf solution - it's not going to get you there. I spent a lot of time playing with different slopes, damping, and padding, as well as making sure to keep the impedance as constant/flat as possible. I don't have any of the measurement/sim tools, so it was old school paper, trial and error, and trusting my ears. With the mid, it obviously needs to be crossed over to protect it, but also allow enough power at the right frequencies to excite it and get the break up thing happening. Getting the right mid and crossover certainly made all the difference and gives the cab the "character".

[JGR]

Originally Posted by 1n3

Ditto. Also interested in your striping technique on the sides.

Cosmetics are a long and painful subject as I had high aspirations and had to keep adjusting for various SNAFU's. The original plan was to do the edges/back in black duratex and the center section in my red crocodile tolex, and put silver piping in the seams. I got it about 90% done and it looked freaking amazing, but at the end I had issues with the tolex separating from the backing, and getting it perfect with the piping and seams is quite honestly out of my league at this point. It was a lot of work that ended in disappointment. I'm OCD about certain things so I just scrapped the cab and started over.

Next plan was to go with the current design but I was going to do custom color duratex for the middle section and baffle (deep purple), and then the black edges and silver paint stripes. Well, Duratex just stopped offering the tinted colors cause their guy got sick - and I didn't want white - so I just went with black and the silver, and added the silver sparkle tolex to the baffle for some subtle bling. Also had silver piping around the grill which looked amazing IMO, but it was creating some buzzing problems, so I 86'd it last night. Here's a pic with the piping on the grill - looks sweet and I'm bummed.



But what you really asked about were the silver strips - I routed an ~1/16 deep channel in the panels before assembly and they are painted with the silver paint. I'm really happy with they way they look, but I've spent an absolutely stupid amount of time masking and painting to get them to look right. I'm actually building four cabs, so that cosmetic aspect turned into a huge time suck.

[JGR]

Originally Posted by 3rdcurve

+1

Amazed at how great it sounds with a guitar. What kind of sensitivity are you at with the cab?

Thanks. I really need to get a better guitar clip, cause I'm really amazed at how good it sounds, but it takes a bit more to capture it on video.

The sensitivity is about 98 dB, with a rise in the upper mids and treble region. It's does really well actually for a single sealed driver cab, but I think running in pairs is definitely in order which is why I'm building four of them. I didn't build a single 2x15 simply because it's harder for me to do a bigger cab by myself in the space I have, and a pair should be easy to carry like a couple of suitcases. They are only 14" deep and well-balanced which makes carrying a lot less awkward compared to a lot of cabs.

It handles a lot of power - I smoked my original driver on the first prototype pumping 1800 watts into it from the bridged CA9 full blast - it did great for a good hour straight until I melted it. Sounded great right until that abrupt silence. Expensive lesson, totally my fault. I'm looking forward to getting the second one up and running this week. A pair should be a pretty devastating stack.

[JGR]

Got a couple more videos loading. The first is more noodling on with the Axe Fx - batteries ran out so it got cut off.

http://youtu.be/aIRe7Oelbto

The second one is with my preamp running clean, dirty, and in-between.

http://youtu.be/zaz2lekoaJw

[1n3]

Thanks for the info on the stripes. Sounds pretty painstaking.

Did I miss the driver info elsewhere, or is that confidential?

[JGR]

Originally Posted by 1n3

Thanks for the info on the stripes. Sounds pretty painstaking.

Did I miss the driver info elsewhere, or is that confidential?

Yeah, it was a bigger pain than I anticipated but I think it looks sharp. The cool thing is that Duratex is great to work with and you can get some really nice results if you take the time - I did three coats, working in sections on the cabs due to the stupid silver lines. I painted on the first two coats with a brush and then rolled over it with the loaded textured roller. I just rolled the last coat. Once you get the application technique down in terms of pressure, speed, loading the roller, etc., you can get a really nice finish similar to tolex IF you take the time. The Duratex is the one bright spot in the finishing nightmare - doesn't smell, dries fast, perfect viscosity and working time, etc. I really dig it, and I hope they bring back the colors eventually. I talked to them and they said it was fairly involved tinting it, so I didn't want to chance it though I know some folks have found other workarounds recently.

Regarding the drivers, I'd rather not say to keep the options open down the road should I ever decide to do something commercially - it's not on the immediate horizon, but it's always nice to have the option. If that ever did happen, the preamps would be much more likely than the cabs. They are a lot of work and it's hard if you don't have the space to keep a dedicated shop. I built four simply because the setup takes so much time I figured I might as well. Wood is reasonable and I don't have to load them.

I'd like to thank all the great TB'ers who have produced some amazing DIY stuff over the years - amps and cabs - it's inspiring, and I have learned a great deal. I say if you have an idea, go for it - it's extremely rewarding in the end if you are willing to work at it, especially when you can make something that kicks the poop out of a lot of the commercial offerings.

[Drop-D]

Sounds great, man!

Great playing, too.

[1n3]

Originally Posted by JGR

Yeah, it was a bigger pain than I anticipated but I think it looks sharp.

It looks sharp to me. In these photos, at least, it looks like a commercial cab. Details like that make the difference.

[JimmyM]

Nice!

[DJJazzV]

That is awesome! Congratulations!

[astack]

Congrats on a successful build! Working through the crossover design sounds like a huge undertaking, glad to hear you found a circuit that works for you.

Your description sounds a bit like a sealed Baer cab (my closest reference piece of gear), both in concept and design with the mid delivering the grit. Great melding of new school design techniques with old school tone goals.

And I also dig the silver stripes - that detail is under-used on bass cabs, imo. What kind of grill is that? Looks great with the baffle covering.

[beans-on-toast]

That's a classy looking cab. It cops the look of a VOX.

[JMac4strngr]

Awesome work!
IMO-Attention to detail allways pays off in the end. Great looking and sounding cab, I absolutely dig it.

[eyeballkid]

see, now i HAVE to come in person for the preamp update!.. i gotta see those in person and have you talk me out of buying two of em!